Language：English   Publishing type：Research paper (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/acs.jafc.1c05987

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Chemical Society of Japan  

DOI： 10.1246/cl.210613

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

Thelepamide, an unique ketide-amino acid isolated from a marine annelid wormThelepus crispus, has a unique oxazolidinone ring derived from cysteine, glycine and valine. Rareness in nature as well as promising bioactive possibility make the oxazolidinone ring an attractive synthetic target. The hydroxy oxazolidinone fragment of thelepamide was prepared by acid-catalysedN,O-acetal formation between a ketoamide and formaldehyde. Lactone-carbonyl selective isopropyl addition to an oxazilidine-dione under Grignard conditions also forms the target compound.

DOI： 10.1080/14786419.2020.1809398

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/14786419.2021.1922906

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/14786419.2021.1916016

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Language：English   Publishing type：Part of collection (book)   Publisher：Springer US  

Depending on the strain, influenza A virus causes animal, zoonotic, pandemic, or seasonal influenza with varying degrees of severity. Two surface glycoprotein spikes, hemagglutinin (HA) and neuraminidase (NA), are the most important influenza A virus antigens. NA plays an important role in the propagation of influenza virus by removing terminal sialic acid from sialyl decoy receptors and thereby facilitating the release of viruses from traps such as in mucus and on infected cells. Some NA inhibitors have become widely used drugs for treatment of influenza. However, attempts to develop effective and safe NA inhibitors that can be used for treatment of anti-NA drugs-resistant influenza viruses have continued. In this chapter, we describe the following updates on influenza A NA inhibitor development: (i) N-acetylneuraminic acid (Neu5Ac)-based derivatives, (ii) covalent NA inhibitors, (iii) sulfo-sialic acid analogs, (iv) N-acetyl-6-sulfo-β-D-glucosaminide-based inhibitors, (v) inhibitors targeting the 150-loop of group 1 NAs, (vi) conjugation inhibitors, (vii) acylhydrazone derivatives, (viii) monoclonal antibodies, (ix) PVP-I, and (x) natural products. Finally, we provide future perspectives on the next-generation anti-NA drugs.

DOI： 10.1007/978-1-0716-2635-1_21

PubMed

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Authorship：Corresponding author   Language：English   Publishing type：Part of collection (book)   Publisher：Springer US  

Methods to synthesize influenza virus inhibitors with fluoro, phosphono, and/or sulfo functional groups are described. The resulting sialic acid analogues are produced from the natural substrate N-acetylneuraminic acid as starting material. Fluorescent assay methods for inhibition of influenza neuraminidase and virus proliferation are also provided.

DOI： 10.1007/978-1-0716-2635-1_20

PubMed

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Authorship：Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

<title>Abstract</title>
Synthesis of assumed natural (12R,13S)-enantiomers of pyriculariol (1) and dihydropyriculariol (2), phytotoxins isolated from rice blast disease fungus, Pyricularia oryzae, was achieved using Wittig reaction or microwave-assisted Stille coupling reaction as the key step. The synthesis revealed that the natural 1 and 2 are racemates. Foliar application test on a rice leaf indicated that both the salicylaldehyde core and side chain were necessary for phytotoxic activity. The fungus is found to produce optically active phytotoxins when incubated with rotary shaker, but racemic ones when cultured using an aerated jar fermenter.

DOI： 10.1093/bbb/zbaa002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

<title>Abstract</title>
Pyricularia oryzae is one of the most devastating plant pathogens in the world. This fungus produces several secondary metabolites including the phytotoxin pyriculols, which are classified into 2 types: aldehyde form (pyriculol and pyriculariol) and alcohol form (dihydropyriculol and dihydropyriculariol). Although interconversion between the aldehyde form and alcohol form has been predicted, and the PYC10 gene for the oxidation of alcohol form to aldehyde is known, the gene responsible for the reduction of aldehyde to alcohol form is unknown. Furthermore, previous studies have predicted that alcohol analogs are biosynthesized via aldehyde analogs. Herein, we demonstrated that an aldo/keto reductase PYC7 is responsible for the reduction of aldehyde to alcohol congeners. The results indicate that aldehyde analogs are biosynthesized via alcohol analogs, contradicting the previous prediction. The results suggest that P. oryzae controls the amount of pyriculol analogs using two oxidoreductases, PYC7 and PYC10, thereby controlling the bioactivity of the phytotoxin.

DOI： 10.1093/bbb/zbaa035

PubMed

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Authorship：Lead author,　Last author,　Corresponding author   Publishing type：Part of collection (book)   Publisher：Springer Berlin Heidelberg  

DOI： 10.1007/7081_2021_52

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Publishing type：Research paper (scientific journal)   Publisher：Pesticide Science Society of Japan  

DOI： 10.1584/jpestics.d20-23

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Authorship：Lead author,　Last author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Pesticide Science Society of Japan  

DOI： 10.1584/jpestics.j20-03

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Publishing type：Research paper (scientific journal)   Publisher：Pesticide Science Society of Japan  

DOI： 10.1584/jpestics.w20-29

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Authorship：Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Forum: Carbohydrates Coming of Age  

DOI： 10.4052/tigg.1801.1e

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1584/jpestics.D19-024

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Language：English   Publishing type：Research paper (scientific journal)  

Previous studies have utilized monoamine oxidase (MAO) and L-3,4-dihydroxyphenylalanine decarboxylase (DDC) for microbe-based production of tetrahydropapaveroline (THP), a benzylisoquinoline alkaloid (BIA) precursor to opioid analgesics. In the current study, a phylogenetically distinct Bombyx mori 3,4-dihydroxyphenylacetaldehyde synthase (DHPAAS) is identified to bypass MAO and DDC for direct production of 3,4-dihydroxyphenylacetaldehyde (DHPAA) from L-3,4-dihydroxyphenylalanine (L-DOPA). Structure-based enzyme engineering of DHPAAS results in bifunctional switching between aldehyde synthase and decarboxylase activities. Output of dopamine and DHPAA products is fine-tuned by engineered DHPAAS variants with Phe79Tyr, Tyr80Phe and Asn192His catalytic substitutions. Balance of dopamine and DHPAA products enables improved THP biosynthesis via a symmetrical pathway in Escherichia coli. Rationally engineered insect DHPAAS produces (R,S)-THP in a single enzyme system directly from L-DOPA both in vitro and in vivo, at higher yields than that of the wild-type enzyme. However, DHPAAS-mediated downstream BIA production requires further improvement.

DOI： 10.1038/s41467-019-09610-2

PubMed

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Publishing type：Research paper (scientific journal)   Publisher：The Society of Synthetic Organic Chemistry, Japan  

DOI： 10.5059/yukigoseikyokaishi.77.173

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Language：English   Publishing type：Research paper (scientific journal)  

β-d-Galactofuranose (Galf) is a component of polysaccharides and glycoconjugates. There are few reports about the involvement of galactofuranosyltransferases and galactofuranosidases (Galf-ases) in the synthesis and degradation of galactofuranose-containing glycans. The cell walls of filamentous fungi in the genus Aspergillus include galactofuranose-containing polysaccharides and glycoconjugates, such as O-glycans, N-glycans, and fungal-type galactomannan, which are important for cell wall integrity. In this study, we investigated the synthesis of p-nitrophenyl β-d-galactofuranoside and its disaccharides by chemo-enzymatic methods including use of galactosidase. The key step was selective removal of the concomitant pyranoside by enzymatic hydrolysis to purify p-nitrophenyl β-d-galactofuranoside, a promising substrate for β-d-galactofuranosidase from Streptomyces species.

DOI： 10.1016/j.carres.2019.01.005

PubMed

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Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s12161-018-1364-1

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Language：Japanese  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Heterocyclic Chemistry  

DOI： 10.3987/COM-18-14002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURAL PRODUCTS INC  

Reaction of 3,4,6-tri-O-acetyl-a-glucal with silver 4-nitrophenolate in the presence of N-iodosuccinimide and N-bromosuccinimide produced (2,6-dihalo-4-nitro)phenyl 2-halo-2-deoxy-alpha-D-glycopyranosides. Although bromination and iodination of the 4-nitrophenyl group could not be avoided, the resulting (2,6-dihalo-4-nitro)phenylated compounds can be used as substrates or covalent glycosidase inhibitors after deprotection. The stereoselectivity and regioselectivity of the halogenation reactions are described.

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：WALTER DE GRUYTER GMBH  

The genus Saussurea ( Asteraceae) contains about 400 species distributed around Asia and Europe and used in the traditional medicines of many cultures. The main compounds isolated from Saussurea species are terpenoids, in particular, sesquiterpenoids are dominant. This review lists 404 chemical constituents as well as their biological activity (111 references).

DOI： 10.1515/hc-2017-0069

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Two tetranortriterpenoids with new skeletons, xylomexicanins I and J (1 and 2), were isolated during the investigation of chemical constituents from seeds of the Chinese mangrove, Xylocarpus granatum. Xylomexicanin I (1) is an unprecedented limonoid with bridged B- and C-rings. A biosynthesis pathway for 1 from xylomexicanin F is proposed.

DOI： 10.1021/acs.jnatprod.7b00305

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：WALTER DE GRUYTER GMBH  

The genus Ajuga, a member of the Lamiaceae family, is comprised of more than 300 species of annual and perennial herbaceous flowering plants mainly distributed throughout the temperate regions of Asia, Europe, Australia, North America and Africa. These plants are used as folk medicines effective for rheumatic fevers, dysentery, malaria, hypertension, diabetes and gastrointestinal disorders, as well as anthelmintic, astringent, febrifuge -diuretic, antifungal and anti-inflammatory agents. A variety of constituents has been isolated from these plants. This review summarizes the phytochemical progress of the genus Ajuga and lists the compounds isolated up to 2014.

DOI： 10.1515/hc-2017-0064

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

The design, synthesis and application of N-acetylneuraminic acid-derived compounds bearing anomeric sulfo functional groups are described. These novel compounds, which we refer to as sulfo-sialic acid analogues, include 2-decarboxy-2-deoxy-2-sulfo-N-acetylneuraminic acid and its 4-deoxy-3,4-dehydrogenated pseudoglycal. While 2-decarboxy-2-deoxy-2-sulfo-N-acetylneuraminic acid contains no further modifications of the 2-deoxy-pyranose ring, it is still a more potent inhibitor of avian-origin H5N1 neuraminidase (NA) and drug-resistant His275Tyr NA as compared to the oxocarbenium ion transition state analogue 2,3-dehydro-2-deoxy-N-acetylneuraminic acid. The sulfo-sialic acid analogues described in this report are also more potent inhibitors of influenza NA (up to 40-fold) and bacterial NA (up to 8.5-fold) relative to the corresponding anomeric phosphonic acids. These results confirm that this novel anomeric sulfo modification offers great potential to improve the potency of next-generation NA inhibitors including covalent inhibitors.

DOI： 10.1038/s41598-017-07836-y

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Other Link： https://www.nature.com/srep/

Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURAL PRODUCTS INC  

TMSCl works as an acid catalyst precursor for selective esterification of L-aspartic and L-glutamic acids in the presence of primary, secondary and tertiary alcohols. Although excess TMSCl was required for the completion of esterification, the resulting alkyl TMS ether could be azeotropically removed by simple evaporation with alcohol.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Isoalantolactone (IAL) is an active sesquiterpene naturally present in many vegetables, condiments and medicinal plants. In this study, an efficient strategy was developed for the identification of metabolites following the in vivo metabolism and in vitro biotransformation of IAL with rat intestinal bacteria utilizing ultra performance liquid chromatography combined with Triple TOF mass spectrometry (UPLC-Triple TOF-MS/MS). As a result, 46 metabolites including 34 novel sulfur-containing products were identified. The results demonstrated that IAL could undergo general metabolic reactions, including oxidation, hydration, hydrogenation, demethylation, cysteine conjugation and N-acetylcysteine conjugation, but the most noticeable characteristic of IAL metabolism was the H2S addition to the double bond between C-11 and C-13 and subsequent reactions to produce a series of novel sulfur-containing dimers. This is the first study of IAL metabolism in vivo, whose results provide novel and useful data for a better understanding of the safety and efficacy of IAL. (C) 2016 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.foodchem.2016.07.100

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Authorship：Lead author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Alantolactone (AL), an active sesquiterpene originating from Inula helenium, is a potential anticancer and anti-inflammatory agent. However so far, studies on AL metabolism have not been reported. In the present study, we have investigated for the first time the in vivo and in vitro metabolites of AL using ultra performance liquid chromatography combined with time of flight mass spectrometry (UPLC-TOFMS/MS). A unique on-line information-dependent acquisition (IDA) method multiple mass defect filter (MMDF) combined with dynamic background subtraction (DBS) was applied to trace all of the probable metabolites of AL. Five MMDF templates were set according to the core structure of AL and the general metabolite biotransformation patterns, and other five sulfur-containing dimer filter templates were first established on the basis of structural elucidation of AL metabolites obtained from rat intestinal bacteria biotransformation. As a result, 44 metabolites were characterized: 41 metabolites from rat urine, bile and feces after oral administration of AL, and 13 metabolites from AL biotransformation by rat intestinal bacteria. Particularly, 26 metabolites were identified as novel sulfur-containing products. The results indicated that addition of double bond at A(11,13) and oxidization were the main metabolic reactions of AL. A new metabolism pathway to produce addition products of H2S to AL and further generate a series of sulfur-containing dimers of AL was revealed. This study significantly enriched our knowledge about AL metabolism, which will lead to a better understanding of the safety and efficacy of AL. At the same time, the established methodology can be widely applied for the structural determination of the metabolites of other sesquiterpene containing alpha-methylene-gamma-lactone moiety. (C) 2016 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jchromb.2016.08.034

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

An aerobic endosulfan sulfate-degrading bacterium, Rhodococcus koreensis strain S1-1, was isolated from soil to which endosulfan had been applied annually for more than 10 years until 2008. The strain isolated in this work reduced the concentration of endosulfan sulfate (2) from 12.25 mu M to 2.11 mu M during 14 d at 30 degrees C. Using ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS), a new highly water-soluble metabolite possessing six chlorine atoms was found to be endosulfan diol monosulfate (6), derived from 2 by hydrolysis of the cyclic sulfate ester ring. The structure of 6 was elucidated by chemical synthesis of the candidate derivatives and by HR-MS and UPLC-MS analyses. Therefore, it was suggested that the strain S1-1 has a new metabolic pathway of 2. In addition, 6 was expected to be less toxic among the metabolites of 1 because of its higher water-solubility. (C) 2016 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2016.04.021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MICROBIOL RES FOUNDATION  

We identified two new radical scavengers, 12T061A (1, C19H20O7) and 12T061C (2, C20H22O7), from a culture of the Streptonzyces sp. Spectroscopic analysis indicated that these compounds are new julichrome family compounds. Compounds 1 and 2 showed radical-scavenging activity with an ED50 of 370 mu M and 18 mu M, respectively. Moreover, 1 showed tumor cell growth suppressive activity in HepG2 cells, (IC50: 3.6 mu M); however, no suppressive activity was shown in 2 (IC50: &gt; 100 mu M).

DOI： 10.2323/jgam.62.1

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Authorship：Lead author   Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

CiNii Article

CiNii Books

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：BENTHAM SCIENCE PUBL LTD  

Tanshinone IIA is a principal constituent of a dried root or rhizome of Salvia miltiorrhiza Bunge (Danshen or Tanshen in Chinese). This plant has been widely used as traditional Chinese medicine for treatment of several diseases for thousands of years. This review describes biological activities reported for tanshinone IIA.

DOI： 10.2174/1570193X13666160614084004

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

The inhibitory effect of 13 taxanes isolated from the Chinese yew (Taxus chinensis var. mairei) on the proliferation of human cervical cancer HeLa cells were examined using an MTT assay. Four compounds having a hydrophobic cinnamate side chain showed antiproliferative activity, which may be due to increased cell permeability.

DOI： 10.1080/09168451.2016.1194182

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

The spiroacetal [C(9)-C(20)] fragments of spirofungins A and B, antibiotics isolated from Streptomyces violaceusniger Tu 4113, were prepared from a known bromo alcohol derived from (S)-citronellal, using thermodynamically controlled iodolactonization and spiroacetalization as the key steps.

DOI： 10.1515/hc-2015-0193

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

Two minor taxane glycosides were isolated for the first time from the needles of Taxus canadensis. Their structures were characterized as 2 alpha,5 alpha-diacetoxy-10 beta-(6'-O-acetyl-beta-D-glucopyranosyl)oxy-14 beta-[(2'R,3'S)3'-hydroxy-2'-methylbutanoyl] oxytaxa-4(20),11-diene (1) and 2 alpha, 14 beta-diacetoxy-10 beta-(beta-D-glucopyranosyl)oxytaxa-4(20),11-dien-5 beta-ol (2) on the basis of 1D and 2D NMR data analysis and confirmed by high-resolution fast atom bombardment mass spectrometry.

DOI： 10.1515/znb-2015-0074

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Three novel limonoids, 2,3-dideacetylxyloccensin S (1), 30-deacetylxyloccensin W (2), and 7-hydroxy-21-methoxy-3-oxo-24,25,26,27-tetranortirucalla-1,14-diene-23(21)-lactone (3), were isolated from the seeds of the Chinese mangrove, Xylocarpus granatum. The structures were elucidated on the basis of 1D- and 2D-NMR (including H-1- and C-13-NMR, DEPT, H-1,H-1-COSY, HSQC, HMBC, and NOESY) data and confirmed by HR-MS.

DOI： 10.1002/hlca.201400290

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURAL PRODUCTS INC  

Synthetic studies of enacyloxins (ENXs), a series of yellow-colored, polyene-polyol antibiotics produced by Frateuria sp. W-315, are described. The C1'-C8' polyene fragments were prepared using successive Wittig reactions. The C9'-C15' and C10'-C15' fragments were constructed from (S)-isopropylideneglyceraldehyde using Yamaguchi's nucleophilic substitution reaction of acetylide to epoxide, and/or Marshall's allenylindium mediated reaction as the key steps.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PARLAR SCIENTIFIC PUBLICATIONS (P S P)  

The hydrolysis of octachlorodipropyl ether (OCDPE) was investigated in aqueous solutions under a variety of pH conditions (pH 3.0-11.0), temperatures (10-35 degrees C) and with the initial concentrations of OCDPE (1.0-100 mg L-1). OCDPE hydrolysis was found to obey the first-order model and similar rate constant values ranging from 0.0361 +/- 0.0006 to 0.0406 +/- 0.0008 day(-1) were obtained at different initial concentration ranging from 1.0 to 100 mg/L. The rates of OCDPE degradation were pH dependent, with increasing k values being associated with higher pH values. At pH 11.0 OCDPE degradation was &gt;60-fold faster than at pH 3.0. The rate constant of OCDPE hydrolysis increases with the increases of the initial concentration and temperature. When the temperature is increased from 10 degrees C to 35 degrees C, the rate constant of hydrolysis rises 3-fold. The effect of temperature on the rate of OCDPE hydrolysis was characterized using the Arrhenius equation with an estimated energy of activation of 32.01 kJ mol(-1). The hydrolysis products of OCDPE are shown to be 1,1,2-trichloro-3-[(2',3',3'-trichloroallyl)oxy] prop-1-ene and 1,1,2- trichloro-3-(2',3',3',3'- tetrachloropropoxy)prop-1-ene. The possible OCDPE hydrolysis pathway of dehydrochlorination is proposed.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PESTICIDE SCI SOC JAPAN  

The photodegradation kinetics of octachlorodipropyl ether (OCDPE) in aqueous solution have been studied under select conditions. The photodegradation rate constants of OCDPE increase with the increases of temperature and pH. The photolysis rates of OCDPE in the investigated water follow the sequence of pure water&gt;impoundment water&gt;pond water&gt;lake water. The photodegradation product of OCDPE is shown to be 2,3,3-trichloroprop-2-en-1-ol. We propose that the OCDPE photolytic pathways consist of dehydrochlorination and ether cleavage via ionic or radical mediated reaction. (C) Pesticide Science Society of Japan

DOI： 10.1584/jpestics.D14-061

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

The new radical scavenger 12T061C (C20H22O7) has been identified from a culture of Streptomyces species. Spectroscopic elucidation showed that this compound is a new Julichrome family compound. 12T061C shows a potent radical-scavenging activity with an ED50 of 18 mu m that is similar to those of the known antioxidant compounds alpha-tocopherol (ED50 6 mu m) and quercetin (ED50 3 mu m).

DOI： 10.1515/hc-2014-0126

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Dieldrin is one of the most persistent organic pollutants, and its oxidative degradation pathways by aerobic microorganisms to 6,7-trans-dihydroxydihydroaldrin (otherwise known as aldrin-trans-diol) and 9-hydroxydieldrin are well documented. The dieldrin-degrading fungus, Mucor racemosus strain DDF, can decrease dieldrin levels with simultaneous production of a small amount of aldrin-trans-diol. A reduction in the levels of aldrin-trans-diol by strain DDF has also been observed. Based on these results, it has been suggested that strain DDF transforms dieldrin to more polar compounds via aldrin-trans-diol. We have conducted a study to identify the metabolites arising from aldrin-trans-diol. The results showed that strain DDF gave reduced levels of aldrin-trans-diol and also produced unknown metabolites. Ultra performance liquid chromatography-electrospray ionization-mass spectroscopy (UPLC-ESI-MS) analysis indicated the metabolites to be either sulfated- or phosphorylated- derivatives of aldrin-trans-diol, but with the metabolites retaining six chlorine atoms. Therefore, the candidate derivatives were synthesized and the retention times of the natural metabolite and the synthetic phosphate were compared. As a result of a co-injection experiment, the metabolites were determined to be aldrin-trans-diol exo- and endo-phosphates. These results were also supported by high-resolution-fast atom bombardment-mass spectrometry (HR-FAB-MS) of the natural metabolite (Delta = 0.63 ppm). Phosphorylation of aldrin-transdiol is the first reported example of phosphate conjugation in microorganisms. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ibiod.2014.04.005

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Four novel tetranortriterpenoids, xylomexicanins E H (1-4), were isolated from the seeds of the Chinese mangrove, Xylocarpus granatum. Among them, xylomexicanin E (1) represents the first example of limonoid with azaspiro skeleton between B (pyrrolidine) and C rings, whose biosynthetic pathways were proposed. The structures were elucidated on the basis of one- and two-dimensional NMR (including H-1, C-13 NMR, DEPT, H-1-H-1 COSY, HSQC, HMBC, and NOESY) and confirmed by high-resolution mass spectrometry. Compound 2, the second example of a limonoid with a C-9-C-30 linkage, showed moderate activity against the A549 and RERF cell line with IC50 value of 18.83 and 15.83 mu M, (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2014.04.062

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

o-Formyl-m-hydroxycinnamic acid, the most oxidized salicylaldehyde-type phytotoxin isolated from rice blast fungus, Magnaporthe grisea, was synthesized for the first time using 5-(2,2-dimethyl-4H-1,3-benzodioxin) methanol as the starting material, and the proposed structure was confirmed.

DOI： 10.1515/hc-2014-0053

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

An efficient and good yield synthesis of the cyclohexane moiety of enacyloxins, a series of antibiotics isolated from Frateuria sp. W-315, was achieved from D-quinic acid using a successive Barton-McCombie deoxygenation.

DOI： 10.1080/09168451.2014.905192

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

Structural modifications were performed on isoalantolactone in an effort to find compounds with potential anticancer activity. Seven previously unknown adducts of active methylene compounds with isoalantolactone were synthesized by the Michael reaction. Moreover, four derivatives of aryl- substituted isoalantolactone were prepared by the Heck reaction. All synthetic products were evaluated for toxic activities against three different hepatoma cell lines, Bel-7402, SMMC-7721, and Hep G2. Products prepared through the Heck reaction and 3a, b show potential antiproliferative activity against the Hep G2 cell.

DOI： 10.1515/hc-2013-0220

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Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：WALTER DE GRUYTER GMBH  

The genus Neolitsea (Lauraceae) contains over 85 species distributed around the world. These plants have been found to be rich in sesquiterpenes, triterpenes, steroids, and alkaloids. This review summarizes the phytochemical progress and list of all the constituents isolated from the genus Neolitsea over the past few decades. Some biological activities of compounds isolated from this genus are also included.

DOI： 10.1515/hc-2013-0239

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURAL PRODUCTS INC  

A new sesquiterpene, eudesm-11-ene-4 alpha,7 beta,9 beta-triol, was isolated from the EtOH extract of aerial parts of Dichrocephala integrifolia. Its structure was determined on the basis of spectral analysis of ID and 2D NMR data.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

A new taxane, 2 alpha,5 alpha,10 beta-triacetoxy-4 beta,20-epoxytax-11-ene-1 beta,7 beta,9 alpha,13 alpha-tetraol (1), was isolated from the rooted cuttings of the Canadian yew, Taxus canadensis.

DOI： 10.1007/s10600-013-0765-z

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Arteminal, a novel eudesmane sesquiterpenoid, was isolated from the whole plant of Artemisia frigida. The structure was characterized on the basis of spectroscopic methods.

DOI： 10.1007/s10600-013-0767-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER SOC MICROBIOLOGY  

The influenza virus neuraminidase H274Y substitution is a highly prevalent amino acid substitution associated with resistance to the most heavily used influenza drug, oseltamivir. Previous structural studies suggest that the group specific 252 residue ( Y252 in group 1 and T252 in group 2) might be a key factor underlying H274Y resistance. However, H274Y has only been reported in N1 subtypes, which indicates that there must be additional key residues that determine H274Y resistance. Furthermore, we found that members of NA serotype N3 also possess Y252, raising the key question as to whether or not H274Y resistance may also be possible for some group 2 NAs. Here, we demonstrate that the H274Y substitution results in mild oseltamivir resistance for N3. Comparative structural analysis of N3, N1, and their 274Y variants indicates that the interaction of residue 296 ( H in N1 and nonaromatic for other serotypes) with conserved W295 is another important determinant of oseltamivir resistance.

DOI： 10.1128/JVI.01129-13

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

A novel isocomene sesquiterpenoid, 11-hydroxyisocom-2-en-5-one, was isolated from the roots of Echinops spinosissimus subsp. spinosus Greuter. The structure was characterized on the basis of NMR spectroscopic methods, including H-1-H-1 COSY, HMBC, HSQC, and NOESY experiments.

DOI： 10.1007/s10600-013-0696-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

A novel germacrane sesquiterpenolide was isolated from the whole plant of Artemisia frigida. The structure was characterized as 1 alpha,3 alpha-dihydroxy-7 beta,11 alpha H-germacra-4Z,10(14)-dien-12,6 alpha-olide (1) on the basis of spectroscopic methods.

DOI： 10.1007/s10600-013-0694-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Two new limonoids, named xylomexicanins C and D, were isolated from a dichloromethane extract of the seeds of Xylocarpus granatum cultivated in Hainan, China, and their structures were elucidated on the basis of one- and two-dimensional NMR (including H-1, C-13-NMR, DEPT, H-1-H-1 COSY, HSQC, HMBC, and NOESY) and confirmed by high-resolution mass spectrometry. Xylomexicanin C exhibited antiproliferative activity against human breast carcinoma cells (KT).

DOI： 10.1271/bbb.120815

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Torreyanoxane, a novel 3,4-secoglutinane triterpenoid, was isolated from the pulp of Torreya nucifera. The structure was determined on the basis of spectroscopic methods.

DOI： 10.1002/hlca.201200174

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Development of novel influenza neuraminidase inhibitors is critical for preparedness against influenza outbreaks. Knowledge of the neuraminidase enzymatic mechanism and transition-state analogue, 2-deoxy-2,3-didehydro-N-acetylneuraminic acid, contributed to the development of the first generation anti-neuraminidase drugs, zanamivir and oseltamivir. However, lack of evidence regarding influenza neuraminidase key catalytic residues has limited strategies for novel neuraminidase inhibitor design. Here, we confirm that influenza neuraminidase conserved Tyr406 is the key catalytic residue that may function as a nucleophile; thus, mechanism-based covalent inhibition of influenza neuraminidase was conceived. Crystallographic studies reveal that 2 alpha, 3ax-difluoro-N-acetylneuraminic acid forms a covalent bond with influenza neuraminidase Tyr406 and the compound was found to possess potent anti-influenza activity against both influenza A and B viruses. Our results address many unanswered questions about the influenza neuraminidase catalytic mechanism and demonstrate that covalent inhibition of influenza neuraminidase is a promising and novel strategy for the development of next-generation influenza drugs.

DOI： 10.1038/ncomms2487

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Language：English   Publishing type：Research paper (scientific journal)  

A new natural product, 8,8'-bi-3-O-methylquercetin (9), and eight known flavonoids were isolated from the flowers of Achillea millefolium. Their structures were established on the basis of spectral evidence. All the spectral data of these compounds were reassigned after interpretation of their 2D NMR spectroscopic data. Compounds 2, 5, and 7 exhibited antiproliferative activity against human breast cancer cell line MCF7WT. In addition, 2 and 5 showed antiproliferative activity against human prostatic cancer cell line PC-3, while the other compounds did not show inhibitory effects in two human tumor cell lines tested. © 2013 Springer Science+Business Media New York.

DOI： 10.1007/s10600-013-0438-y

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Language：English   Publishing type：Research paper (scientific journal)  

A taxane with an amino-side chain on C-5 was identified for the first time from rooted cuttings of the Canadian yew, Taxus canadensis. The structure was characterized as 2α,10β,13α-triacetoxy-5α-[3'-(N-formyl- Nmethylamino)-3'-phenylpropanoyloxy]taxa-4(20),12-dien-9α-ol (1) on the basis of 1D and 2D NMR data and HR-FAB-MS analyses. The spectra revealed that in CDCl3 solution 1 was composed of two rotamers (1a and 1b) in a ratio of approximately 1:1. © 2013 Springer Science+Business Media New York.

DOI： 10.1007/s10600-013-0458-7

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/cr200058f

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

12-O-beta-D-glucopyranosyl jasmonic acid (JAG) shows unique biological activities, including leaf-closing of Samanea saman. It is expected that the mode of action for such regulation is distinct from that of other jasmonates. We developed high-performance compact molecular probes (CMPs) based on JAG that can be used for the FLAG-tagging of JAG target. We synthesized four hybrid-type JAG-CMP stereoisomers (7, ent-7, 8, and ent-8), which are composed of (-)-12-OH-JA (2)/D-galactopyranoside, (-)-2/L-galactopyranoside, (+)-ent-2/D-galactopyranoside, and (+)-ent-2/L-galactopyranoside moieties, respectively, and we examined their biological features, such as the stereospecific induction of shrinkage, rate of the cellular response, and dependence on potassium channel activity. These features of the JAG-CMPs were completely consistent with those of the original JAG. These results indicate the biological equivalence of JAG and the JAG-CMPs. During the course of such biological evaluations, it was revealed that the biological activity of the CMPs is greatly dependent on the D/L-stereochemistry of a glycon moiety. To the best of our knowledge, this is the first study suggesting that the D/L-stereochemistry of the glycon moiety significantly affects the biological activity of the associated glycoside. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.bmc.2012.08.003

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Two new natural taxanes were isolated from the heartwood of Taxus cuspidata. The structures were established as rel-(2a,5a,7 beta,9a,10 beta,12a)-7,9-bis(acetyloxy)-2-(benzoyloxy)-11,12-epoxy-1,5-dihydroxy-10-[(hydroxyacetyl)oxy]tax-4(20)-en-13-one (1), and (2a,5a,10 beta,14 beta)-taxa-4(20),11-diene-2,5,10,14-tetrol 2-acetate (2) on the basis of spectroscopic analysis.

DOI： 10.1002/hlca.201200045

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Eight sesquiterpene lactones were isolated from the roots of Inula helenium and flowers of I. japonica. Among them, isoalantolactone (3) and santamarine (6) exhibited significant growth inhibitory activities against gynecologic cancer cell lines, while others weakly inhibited the growth of the cell lines (IC50 &lt;= 100 mu m). In addition, 3 significantly inhibited the tumour growth of S180 tumour-bearing mice. Compounds 3 and 6 were not toxic to human embryonic lung fibroblast cells in vitro. These results demonstrated that the antitumour activities are closely related to the structures of the compounds, that is, an alpha-exomethylene-gamma-lactone ring is necessary for these activities.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER TOKYO  

We established a simple, rapid method for gizzerosine analysis in fish meal. Gizzerosine was extracted from fish meal with 0.1 N HCl solution. Samples and standard gizzerosine solutions were absorbed onto a paper disc, which was then set on electrophoresis paper for 18 min, and the paper was dried. Gizzerosine was visualized with Pauly's reagent, and the intensity of the colored spots was digitized and calculated by image processing method software. We achieved successful separation of gizzerosine from other Pauly's reagent-positive components in fish meal extracts. The linearity of gizzerosine estimation using this method was within the range 30-1000 ng (R (2) = 0.99). Gizzerosine was satisfactorily detected and completely separated from histamine and other Pauly's reagent-positive compounds. This method does not require expensive instruments or tedious pretreatment to eliminate interfering compounds, such as histamine or histidine. It also uses less reagent compared with high-performance liquid chromatography. Moreover, it is a simple, rapid, sensitive, and reproducible method. It is suitable for monitoring gizzerosine in fish meal products that contain as little as 10 ppm gizzerosine.

DOI： 10.1007/s12562-012-0507-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Two novel sesquiterpene dimers, achillinin B and C, were isolated from the flowers of Achillea millefolium. The structures were elucidated by extensive spectroscopic analysis. A plausible biosynthetic pathway of achillinin B and C by Diels-Alder reaction of the corresponding guaiane sesquiterpenoids is also discussed. (C) 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2012.03.039

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Ten 1,10-secoguaianolides were isolated from the flowers of Achillea millefolium. Their structures were determined on the basis of spectroscopic methods. Three of them (millifolides A-C) including two dimeric sesquiterpenoids exhibit new skeletons. Seco-tanapartholide A exhibited moderate cell growth inhibitory activity against the human cancer cell line MCF7WT (IC50 = 5.51 mu m) in vitro.

DOI： 10.5560/ZNB.2012-0028

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER & CO  

A novel 6/12-membered bicyclic taxane with a 13,17-ether bridge, named canataxpyran A, was isolated from the needles of Taxus canadensis. The structures were characterized as 7 beta,9,10 beta,20-tetracetoxy-13 beta,17-epoxy-3,8-secotaxa-3E,8E,11-triene-2 alpha,5 alpha-diol (designated as canataxpyran A, 1). This bicyclic taxane gradually decomposed in CDCl3 to give the corresponding enones, 10 beta,20-diacetoxy-13 beta,17-epoxy-4 alpha,5 alpha-dihydroxy-3,8-secotaxa-2E,7E,11-trien-9-one (canataxpyran B, 2) and 5 alpha,10 beta,20-triacetoxy-13 beta,17-epoxy-4 alpha-hydroxy-3,8-secotaxa-2E,7 E,11-trien-9-one (canataxpyran C, 3). Compound 1 is the first example of a natural 3,8-secotaxane with 13,17-oxygen bridge.

DOI： 10.1515/hc-2012-0035

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Paclitaxel (Taxol), one of the most potent anticancer drugs, is a microtubule-stabilizing compound that inhibits microtubule depolymerization within the cell. The structure of paclitaxel is composed of two key elements, a taxane ring and an N-benzoylphenylisoserine side chain at C-13. A number of natural and artificial compounds with taxane skeletons have been isolated, but almost none of their bioactivities have been evaluated. In this study, we focused on compounds having a taxane skeleton structure and examined their effects on tubulin dynamics. Although none of these compounds had an N-benzoylphenylisoserine side chain, three were found to promote tubulin assembly. On the other hand, one compound inhibited tubluin assembly in a way similar to nocodazole. These compounds exhibited novel structure-activity relationships of taxane compounds.

DOI： 10.1271/bbb.110797

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：COGNIZANT COMMUNICATION CORP  

We previously reported that 9-methylstreptimidone, a piperidine compound isolated from a culture filtrate of Streptomyces, induces apoptosis selectively in adult T-cell leukemia cells. It was screened for a compound that inhibits LPS-induced NF-kappa B and NO production in mouse macrophages. However, 9-methystreptimidone is poorly obtained from the producing microorganism and difficult to synthesize. Therefore, in the present research, we studied the structure-activity relationship to look for new selective inhibitors. We found that the structure of the unsaturated hydrophobic portion of 9-methylstreptimidone was essential for the inhibition of LPS-induced NO production. Among the 9-methylstreptimidone-related compounds tested, (+/-)-4,alpha-diepi-streptovitacin A inhibited NO production in macrophage-like cells as potently as 9-methylstreptimidone and without cellular toxicity. Moreover, this compound selectively induced apoptosis in adult T-cell leukemia MT-1 cells.

DOI： 10.3727/096504012X13425470196056

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/cr100147u

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Rice blast fungus, Magnaporthe grisea, produces a series of salicylaldehyde-type phytotoxins such as pyriculol, pyricuol, and pyriculariol. Plausible biosynthetic intermediates of these phytotoxins were synthesized in deuterium labeled forms using the Stille coupling reaction as the key step, and subjected to biotransformation by the fungus. Heptatrienyl-salicylaldehyde was converted into dihydropyriculol by the fungus by a shaking culture. A new biosynthetic pathway comprising both oxidation and reduction is proposed.

DOI： 10.1002/ejoc.201100771

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Both (+)- and (-)-omega-trifluorononactic acid, a designed analogue of nonactic acid, were synthesized. The racemic acid, prepared by using cis-selective iodoetherification, was resolved as the corresponding (S)-O-acetylmandelates. The structure was determined by X-ray crystallographic analysis.

DOI： 10.1055/s-0030-1260234

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Diabietane ether (1), a new abietane dimer connected by an ether linkage, and two known abietane diterpenoids (2 and 3) were isolated from the needles of Taxus cuspidata.

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Rice blast disease, caused by infection of rice blast fungus Magnaporthe grisea (Hebert) Barr. (perfect stage of Pyricularia oryzae Cabara), has been the most serious pest for rice. The fungus mainly produces several phytotoxic compounds according to fermentation method, i. e., dihydropyriculol (1), pyriculol (2), and pyriculone (3) by a shaking culture; dihydropyriculariol (5) and pyriculariol (6) by an aeration and agitation culture; and tenuazonic acid by a stationary culture in a soy sauce-sucrose medium. Pyricuol (4) together with 2 were produced by a shaking culture with a potato dextrose medium. These salicylaldehyde-type phytotoxins are common metabolites of blast fungi of various host plants except a ginger. To develop novel methods to control the blast disease a better knowledge of the biosynthesis is necessary. Synthesis of both enantiomers of pyricuol (4) from (R)- and (8-lactates was achieved using [2,31-Wittig rearrangement and Stille coupling reactions as the key steps. This revealed that the natural 4 has an R-configuration. Racemic synthesis is also reported. On the other hand, optically active pyriculariol (6) was synthesized from L-rhamnose using microwave assisted Stille coupling reaction of the unprotected substrates as the key step. A comparison of the CD spectra and 1H NMR spectra of the corresponding MTPA esters found that natural pyriculariol (6) existed as a racemate. Biotransformation of the plausible biosynthetic intermediates 7-d2 and 8-d in deuterio forms was also examined. Not diol 7-d2 but aldehyde 8-d was converted by the fungus M. grisea into dihydropyriculariol (1-d) in soy sauce-sucrose medium under a shaking culture. Foliar application test of the synthetic compounds on rice leaves revealed that both a salicylaldehyde and a side chain fragments are necessary for the necrotic activity. In conclusion, the blast fungus M. grisea produced 1, 2, and 4 in optically active forms and 5 and 6 as racemates depending on the culture conditions. Additionally, it is interesting that both oxidation and reduction would be coexist at the later stage of biosynthesis of these phytotoxins.

DOI： 10.24496/tennenyuki.53.0_661

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

A mimic of a plausible biosynthetic intermediate of bishomononactic acid, one of the monomers of macrotetrolide antibiotics (polynactin), was synthesized as a thiol ester. FAB-MS analysis showed that fermentation of polynactin producing Streptomyces griseus with the compound, afforded the unnatural polynactins containing bishomononactic acid(s).

DOI： 10.1515/HC.2011.021

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Macrotetrolide alpha (1), a designed polynactin analog composed of (+)- and (-)-bishomononactic acids, was synthesized. The monomeric acids were prepared using cis-selective iodoetherification and optical resolution of the corresponding O-acetylmandelates as the key steps. Esterification and macrolactonization of the monomers were performed by Corey-Mukaiyama-Gerlach method. Compound 1 showed no immunosuppressive activity contrary to other natural polynactin congeners. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2011.07.012

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

White rot fungi can degrade a wide spectrum of recalcitrant organic pollutants, including polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated biphenyls (PCBs). In this experiment, 20 white rot fungi, belonging to genus Phlebia, were investigated for their ability to degrade dieldrin. Based on the screening results, we further investigated Phlebia acanthocystis, Phiebia brevispora, and Phlebia aurea to determine their degradation capacity and metabolic products towards dieldrin and aldrin. The three fungi were able to remove over 50% of dieldrin in a low nitrogen medium, after 42 d of incubation. Three hydroxylated products were detected as metabolites of dieldrin, suggesting that in Phlebia strains, hydroxylation reactions might play an important role in the metabolism of dieldrin. In contrast to dieldrin, aldrin exhibited higher levels of degradation activity. Over 90% of aldrin was removed after 28 d of incubation, and several new metabolites of aldrin in microorganisms, including 9-hydroxyaldrin and two carboxylic acid products, were detected in fungal cultures. These results indicate that the methylene moiety of aldrin and dieldrin molecules might be prone to enzymatic attack by white rot fungi. In this study, we describe for the first time a new metabolic pathway of both compounds by fungi of genus Phlebia. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.chemosphere.2011.06.028

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

A novel 6/8/6-membered taxane with a rare C-12(13)-double bond and rare 2(3 -&gt; 20)abeotaxane were isolated from the needles of Taxus canadensis. Their structures were characterized as 7 beta,9 alpha,10 beta-triacetoxy-taxa-4(20),12-diene-2 alpha,5 alpha,11 beta-triol (1) and 2 alpha,7 beta,10 beta-triacetoxy-5 alpha-hydroxy-2 (3 -&gt; 20)abeotaxa-4(20),11-diene-9,13-dione (2) on the basis of 1D and 2D spectroscopic data. 1 is the first example of a natural taxane without substitution at both C-13 and C-14.

DOI： 10.1271/bbb.110223

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Achillinin A (2 beta,3 beta-epoxy-l alpha,4 beta,10 alpha-trihydroxyguai-11(13)-en-12,6 alpha-olide, 1), a new guaianolide isolated from the flower of Achillea millefolium, exhibited potential antiproliferative activity to A549, RERF-LC-kj and QG-90 cells with 50% inhibitory concentration (IC50) values of 5.8, 10 and 0.31 mu m, respectively.

DOI： 10.1271/bbb.110234

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Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1002/cbdv.201000176

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Sinenxan H [2 alpha,14 beta-diacetoxytaxa-4(20),11-diene-5 alpha, 10 beta-diol, 1] was isolated from the heartwood of Taxus cuspidata, for the first time from natural sources. Compound 1 was found to be readily converted into 2 alpha-acetoxytaxa-4(20),10,12(18),13-tetraen-5 alpha-ol (2), the first example of a taxane with 10,11- and/or 13,14-double bond(s) and a conjugated triene system, in CDCl(3).

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER & CO  

A new taxane peroxide, 4 alpha,10 beta,13 alpha-acetoxy-2 alpha-benzoyloxy-7 beta,9 alpha-epidioxy-5 beta,20-epoxytax-11-en-1 beta-ol (1), was isolated and characterized for the first time in rooted cuttings of the Canadian yew, Taxus canadensis.

DOI： 10.1515/HC.2011.019

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER & CO  

The C16&apos;-C23&apos; fragments of enacyloxins, a series of antibiotics isolated from Frateuria sp. W-315, were synthesized from D-arabinose.

DOI： 10.1515/HC.2011.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER & CO  

The C9&apos;-C15&apos; fragment of enacyloxins, a series of antibiotics isolated from Frateuria sp. W-315, was synthesized from diethyl D-tartrate.

DOI： 10.1515/HC.2011.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ACADEMIC PRESS INC ELSEVIER SCIENCE  

We isolated a novel aerobic dieldrin-degrading bacterium from an enrichment culture in a soil-charcoal perfusion system. Enrichment culture using a soil-charcoal perfusion system was an effective way to obtain microorganisms that degrade recalcitrant compounds. The soil-charcoal perfusion was performed using aldrin trans-diol, which was a metabolite of dieldrin. Aldrin trans-diol had higher bioavailability (2.5 mg/l) than dieldrin (0.1-0.25 mg/l), therefore it is possible for microorganisms to utilize it as a substrate in soil. After 100 days of circulation and three exchanges of the medium, the enriched charcoal was harvested and a bacterium isolated. The isolate was designated as strain KSF27 and was found to be closely related to Pseudonocardia spp. as determined by 16S rRNA sequencing analysis. Strain KSF27 degraded aldrin trans-diol by 0.05 mu mol/l from an initial concentration of 25.5 mu mol/l. The metabolite of aldrin trans-diol was detected by HPLC/MS and determined to be aldrindicarboxylic acid based on retention time and the MS fragment. Moreover, strain KSF27 degraded dieldrin from 14.06 mu mol/l to 2.01 mu mol/l over a 10-day incubation at 30 degrees C. This strain degraded dieldrin and other persistent organo-chlorine pesticides, such as alpha-endosulfan, beta-endosulfan, endosulfan sulfate, heptachlor, heptachlor epoxide and chlordecone. (C) 2011 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2011.06.096

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Three new taxanes, 2 alpha, 9 alpha, 10 beta-triacetoxy-13 alpha-(beta-D-glucopyranosyloxy)taxa-4(20), 11-dien-5 alpha-ol (1), 5 alpha, 10 beta, 13 alpha-triacetoxytax-11-ene-2 alpha,7 beta,9 alpha,20-tetraol (2), and 5 alpha, 10 beta, 13 beta-triacetoxy-2 alpha, 7 beta-dihydroxy-2(3 -&gt; 20)abeotaxa-4(20), 11-dien-9-one (3), were isolated from the leaves of the Japanese yew, Taxus cuspidata. Compound 1 is the first example of a taxane with 13-glycosidic linkage.

DOI： 10.1055/s-0030-1250333

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Four novel oxepin-containing pyrimidines, namely oxepinamides D-G (1-4), were isolated from cultures of Aspergillus puniceus F02Z-1744. The structures of 1-4 were elucidated by analyzing their spectroscopic data generated by 1D and 2D NMR and MS methods. The configurations of 1 and 2 were established based on single-crystal X-ray crystallographic analysis. All four compounds 1-4 showed transcriptional activation on Liver X Receptor alpha (LXR alpha) with EC(50) values of 10.6, 12.8, 13.6, and 12.1 mu M, respectively.

DOI： 10.1002/ejoc.201000812

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-BLACKWELL  

DOI： 10.1002/cbdv.201000027

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Two new phytoecdysteroids with a 20,22-acetal group were identified for the first time from the needles of the Canadian yew, Taws canadensis. Their structures were characterized as ponasterone A 20,22-p-hydroxybenzylidene acetal (1) and ponasterone A 20,22-acetonide (2) on the basis of 1D, 2D NMR evidence and high-resolution FABMS analysis.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

An aerobic dieldrin-degrading fungus, Mucor racemosus strain DDF, was isolated from a soil to which endosulfan had been annually applied for more than 10 years until 2008 Strain DDF degraded dieldrin to 1 01 mu M from 143 mu M during a 10-day incubation at 25 degrees C Approximately 0 15 mu M (9%) of aldrin transdiol was generated from the dieldrin degradation after a 1-day incubation The degradation of dieldrin by strain DDF was detected over a broad range of pH and concentrations of glucose and nitrogen sources. Extracellular fluid without mycelia also degraded dieldrin Strain DDF degraded not only dieldrin but also heptachlor, heptachlor epoxide, endosulfan, endosulfan sulfate, DDT, and ODE Endosulfan sulfate and heptachlor were degraded by 0.64 mu M (95%) and 0.75 mu M (94%), respectively, whereas endosulfan and DDE were degraded by 2 42 mu M (80%) and 3 29 mu M (79%), respectively, and DDT and heptachlor epoxide were degraded by 695 mu M (49 3%) and 5 36 mu M (67 5%), respectively, compared with the control, which had a concentration of approximately 14 mu M. These results suggest that strain DDF could be a candidate for the bioremediation of sites contaminated with various persistent organochlorine pesticides including POPs

DOI： 10.1021/es1000227

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BENTHAM SCIENCE PUBL LTD  

The genus Valeriana (Valerianaceae) contains over 250 species distributed around the world and used in traditional medicines of many cultures. The main compounds isolated from Valeriana species are essential oils, valerenic acid and its derivatives and iridoids, accumulated mainly in the roots and rhizomes. This review lists 135 chemical constituents as well as their biosynthesis and bioactivity as reported by the end of 2008 (80 references).

DOI： 10.2174/157019310791065537

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

One novel tetranortriterpenoid derivative, xylocarponoid A, representing the first example of C28 skeleton limonoid, was isolated from the seeds of the Chinese mangrove, Xylocarpus granatum. Its C-1&apos;-epimer, xylocarponoid B, was formed in CDCl3. Their structures were elucidated by extensive spectroscopic analysis. A plausible biosynthetic pathway of xylocarponoid A was proposed. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2009.11.123

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DOI： 10.1111/j.1574-6968.2009.01843.x

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-V C H VERLAG GMBH  

The Asteraceae family comprises ca. 1000 genera, mainly distributed in Asia and Europe. Saussurea DC., as the largest subgenus of this family, comprises ca. 400 species worldwide, of which ca. 300 species occur in China. Most plants in China grow wild in the alpine zone of the Qingzang Plateau and adjacent regions at elevations of 4000 m. Plants of the genus Saussurea (Asteraceae) are used in both traditional Chinese folk medicine and Tibet folklore medicine, since they are efficacious in relieving internal heat or fever, harmonizing menstruation, invigorating blood circulation, stopping bleeding, alleviating pain, increasing energy, and curing rheumatic arthritis. A large number of biologically active compounds have been isolated from this genus. This review shows the chemotaxonomy of these compounds (215 compounds) such as sesquiterpenoids (101 compounds), flavonoids (19 compounds), phytosterols (15 compounds), triterpenoids (25 compounds), lignans (32 compounds), phenolics (23 compounds), and chlorophylls (11 compounds). Biological activities (anti-inflammatory, anticancer, antitumor, hepatoprotective, anti-ulcer, cholagogic, immunosuppressive, spasmolytic, antimicrobial, antiparasitic, antifeedant, CNS depressant, antioxidant, etc.) of these compounds, including structure activity relationships, are also discussed.

DOI： 10.1002/cbdv.20090

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Four stereoisomers of (+)-pteroenone, a defensive metabolite of the abducted Antarctic pteropod Clone antarctica, were synthesized by employing anti-/syn-selective aldol reactions as the key step. These compounds displayed no antifeedant activity against a generally benthic Antarctic fish that does not co-occur with this pteropod.

DOI： 10.1002/hlca.201000258

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER  

There is increasing demand for novel anti-inflammatory drugs with different mechanisms of action. We synthesized a series of isothiocyanates 2b-h based on 6-(methylsulfinyl)hexyl isothiocyanate (6-MITC) found in the pungent spice Wasabia japonica. Inhibitory activities against in-vitro growth of tumor cells and production of nitric oxide (NO) using the mouse macrophage-like cell line J774.1 were noted. All isothiocyanates were optimized by Hartree-Fock/3-21G model, and the log P values and the polar surface area (PSA) values were calculated. Substitution of the methylsulfinyl group (CH(3)S(=O)-R) in 6-MITC with a formyl (CHO-R), a methylsulfanyl (CH(2)S-R) or a methyl (CH(3)-R) group reduced the activities of the parent isothiocyanate. Substitution with a formyl group resulted in lower lipophilicity (log P value) whereas substitution with a methylsulfanyl or methyl group resulted in a lower PSA value. The inhibitory activity of isothiocyanates showed better correlation with their PSA values rather than their partition coefficient (log P) values. Isothiocyanates with higher PSA values and some degree of log P value may have potent biological activity. (C) 2009 Elsevier Masson SAS. All rights reserved.

DOI： 10.1016/j.ejmech.2009.08.005

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

1. Synthesis of procyanidin B1-B4(1-4). Stereoselective synthesis of catechin and epocatechin under intermolecular condensation of equimolar amount of catechin derivatives catalyzed by Yb(OTf)_3. The coupled products were successfully converted to procyanidin B1 (1), B2 (2), B3 (3), and B4 (4), respectively. 2. synthetic of (-)-epicatechin 3-(3"-O-methylgallate) (13) and (+)-catechin 3-(3"-O-methylgallate) (14) A concise synthesis of (-)-epicatechin 3-(3"-O-methylgallate)(13, ECG3"Me), which is a minor constituent of tea, and (+)-catechin 3-(3"-O-methylgallate)(14, CG3"Me) via condensation of equimolar amount of catechin and gallate derivatives has been achieved. The anti-inflammatory effect of the synthetic compounds on TPA-induced inflammation of mouse ears was examined. Compounds 13 and 14 suppressed the TPA-induced inflammation of mouse ears by 50% and 43%, respectively, at a dose of 200μg. 3. Short step synthesis of resveratrol derivative. An efficient synthesis of trimethoxylated resveratrol (20) is presented using advanced Heck reaction promoted by Pd(dba)_2 in the presence of P(t-Bu)_3.

DOI： 10.24496/tennenyuki.51.0_289

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

First total synthesis of (-)-pyriculariol, a phytotoxin isolated from rice blast fungus, Magnaporthe grisea, was achieved to determine the absolute configuration of the natural product to be 5&apos;R,6&apos;S. The key step was Stille coupling reaction using microwave irradiation from -78 degrees C to control the reaction. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2009.05.109

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Both enantiomers and racemate of pyricuol, a phytotoxin isolated from the rice blast disease fungus, Magnaporthe grisea, have been synthesized by using Stille coupling and [2,3]-Wittig rearrangement reactions as the key steps. Both enantiomers induced dark necrotic lesions on rice leaves almost equally, but did not affect the growth of rice second leaf sheath and the germination of lettuce. Only natural enantiomer promoted the root growth of rice and lettuce. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2009.05.052

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Jasmonates are potent lipid regulators in plants that play pivotal roles in their biological activities. Methyl jasmonate (MJ) is very effective at inducing the myelomonocytic differentiation of human myeloid leukemia HL-60 cells. We examined the gene expression profiles associated with exposure to MJ using cDNA microarrays, and compared the results with those obtained with other inducers of differentiation, such as all-trans retinoic acid (ATRA), 1 alpha,25-dihydroxyvitamin D(3) (VD(3)), isopentenyladenine (IPA) and cotylenin A (CN-A). Many genes were upregulated, and only a small fraction was downregulated, upon exposure to the inducers. MJ, IPA and CN-A, but not ATRA or VD3, immediately induced the expression of mRNA for the calcium-binding protein S100P. The gene expression profile induced by MJ resembled that induced by IPA, suggesting that these inducers share many common signal transduction systems for inducing the differentiation of leukemia cells. Methyl 4,5-didehydrojasmonate was about 30 times more potent than MJ and the natural form of the stereoisomer was more effective than the unnatural isomer. It significantly stimulated both the functional and morphological differentiation of leukemia cells that had been freshly isolated from patients with hematological malignancies. Jasmonate derivatives may be promising therapeutic agents for differentiation therapy of leukemia.

DOI： 10.1038/leu.2008.347

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Magnolia species are widely cultivated in Japan as garden plants, and have been found to contain various compounds, including alkaloids, terpenoids, lignans, and neolignans. The constituents of the mature fruits of M. denudata were investigated, and two new phenolic derivatives, named denudalide and denudaquinol, were isolated and characterized, together with a known neolignan compound (denudatin A). Denudalide and denudaquinol showed cytotoxicity against the SFME and r/mHM-SFME-1 cell lines.

DOI： 10.1271/bbb.80597

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Taxusecone, 2 alpha,7 beta,9 alpha,10 beta-tetraacetoxy-5 alpha,12-dihydroxy-11,12-secotax-4(20)-ene-11,13-dione (1), a novel taxane with an unprecedented skeleton, was isolated from the needles of Taxus cuspidata.

DOI： 10.1271/bbb.80698

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Two new mexicanolide-type limonoids, named xylomexicanin A (1) and xylomexicanin B (2), were isolated from seeds of the Chinese mangrove Xylocarpus granatum. Their structures were elucidated on the basis of spectroscopic methods. Compound 1 exhibited antiproliferative activity against human breast carcinoma cells (KT), while 2 did not show inhibitory effects on eleven human tumour cell lines tested.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Two 11 (1.5 -&gt; 1)abeotaxanes having a tetrahydrofuran ring along the carbon atoms C-2, C-3 C-4, C-20 were identified for the first time from the needles of the Canadian yew, Taxus canadensis. The compounds could be identified as 4 alpha 10 beta,13 alpha-triacetoxy-15-benzovloxy-2 alpha,20 beta-epoxy- 11(15 -&gt; 1)abeotax-11-ene-5 alpha,7 beta,9 alpha-triol (1) and 4 alpha,7 beta,9 alpha,10 beta,1.5-pentaacetoxy-2 alpha,20 beta-epoxy-11 (1.5 -&gt; 1)abeotax-11-ene-5 alpha, 13 alpha-diol (2) on the basis of 1D-,2D-NMR evidence and high-resolution FABMS analysis. Compound 1 showed weak growth inhibitory activities against T-98 and MM1-CB cells in vitro.

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Language：English   Publishing type：Research paper (international conference proceedings)  

Daphniphyllum alkaloids are a growing group of secondary metabolites of great structural diversity, with complex polycyclic skeletons from Daphniphyllum plants. A large number of new Daphniphyllum alkaloids with novel frameworks have been isolated from Daphniphyllum species in the past decade. These unusual structural characteristics will attract the attention of scientists in the fields of organic synthesis, bioactivity evaluation and biosynthetic studies. This review lists all the Daphniphyllum alkaloids as well as their biosynthesis, bioactivity and synthesis reported by the end of first half of 2008. © 2009 Bentham Science Publishers Ltd.

DOI： 10.2174/138527209787847345

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-V C H VERLAG GMBH  

The plants of genus Celastrus, distributed in Asia, have been used as natural insecticides and folk medicines to treat fever, chill, joint pain, edema, rheumatoid arthritis, and bacterial infection in China for a long time. This contribution reviews the chemical constituents, 1-144, isolated from the plants in genus Celastrus in the past few decades, and their biological activities. The compounds listed are sesquiterpenes (beta-agarofurans), diterpenes, triterpenes, alkaloids, and flavonoids.

DOI： 10.1002/cbdv.200700403

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A concise synthesis of (-)-epicatechin 3-(3-O-methylgallate) (1; ECG3"Me), which is a minor constituent of tea, and (+)-catechin 3-(3-O-methylgallate) (2; CG3"Me) via condensation of equimolar amount of catechin and gallate derivatives has been achieved. The anti-inflammatory effect of the synthetic compounds on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation of mouse ears was examined. Compounds I and 2 suppressed the TPA-induced inflammation of mouse ears by 50 and 43%, respectively, at a dose of 200 mu g. Their activities are stronger than those of indomethacin and glycyrrhetinic acid, the normally used anti-inflammatory agents.

DOI： 10.1002/cbdv.200800224

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG Z NATURFORSCH  

Lipase-catalyzed resolution of 2-exo-7-syn-7-(1&apos;-propynyl)norbornan-2-ol, a key synthetic intermediate for jasmonoids was achieved using vinyl chloroacetate as an acyl donor.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Analogs of cortistatins, a series of anti-angiogenic compounds isolated from the Indonesian marine sponge Cortisium simplex, were synthesized from estrone by using the Suzuki-Miyaura coupling reaction as the key step. The estrone-isoquinoline hybridized compound showed selective inhibitory activity against the proliferation and VEGF-induced migration of HUVEC.

DOI： 10.1271/bbb.80562

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Taxpropellane, the first example of a taxane with an unprecedented 6/5/5/6/4/5-membered ring hexacyclic skeleton ([3.3.2]propellane), was isolated from the needles of Taxus canadensis. This compound would be derived from a normal 6/8/6 taxane by a [2+2] cycloaddition reaction between the 3,4- and 11,12-double bonds. ( (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

DOI： 10.1002/ejoc.200800587

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/cr078350s

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The L-acid (C1-C18) fragment of pamamycin-593 and de-N-methylpamamycin-579, strong aerial mycelium-inducers of Streptomyces alboniger, was synthesized using a cis-selecfive iodoetherification and a nucleophilic addition of a cerium acetylide to an aldehyde as the key steps. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

DOI： 10.1002/ejoc.200800600

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

The periplasmic glucans of Mesorhizobium loti were isolated and separated into fractions according to their acidity. NMR spectroscopy confirmed their backbone structure to be a cyclic beta-(1--&gt;2)-D-glucan as in the case of other rhizobia, and revealed no non-glycosidic substituents in the neutral fraction, and glycerophosphoryl and succinyl residues as major and minor substituents, respectively, in the anionic fractions. MALDI-TOF mass spectrometry showed that the anionic glucans contain one, two, or three such substituents per molecule according to their acidity, and, in contrast, that all the anionic subfractions have a similar size distribution to that of the neutral glucans, where molecules composed of 20-24 glucosyl residues are predominant. These results clarify the periplasmic glucan composition in terms of charge-to-mass ratios in M. loti cells. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.carres.2008.07.007

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WALTER DE GRUYTER GMBH  

A new taxane with an amino side chain on C-5 and a new 11(15 -&gt; 1)abeotaxane having a tetrahydrofuran ring along carbon atoms C-2, C-3, C-4, C-20 identified for the first time from the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 2 alpha,7 beta,9 alpha, 10 beta, 13-pentaacetoxy-11 beta-hydroxy-5a-(2'-hydroxy,3'-N,N-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20), 12-diene (1) and 13 alpha,20 beta-diacetoxy- 5 alpha,7 beta,9 alpha,10 beta-tetrahydroxy-2 alpha,20-epoxy-11(15 -&gt; 1)abeotaxa-11, 15-diene (2) on the basis of 1D, 2D NMR spectroscopy and high-resolution FABMS analysis. Taxane 1 contains a rare C-12, C-13 double bond and a basic side chain, while taxane 2 bears a rare isopropenyl group at C-1.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A taxane with an amino-side chain on C-5 was identified for the first time from rooted cuttings of the Canadian yew, Taxus camadensis. The structure was characterized as 7 beta,9 alpha,10 beta,13 alpha-tetraacetoxy-5 alpha-[3&apos;-(N-formyl-N-methylamino)-3&apos;-phenylpropanoyl]oxytaxa-4(20),12-diene (1) on the basis of 1D-, 2D-NMR data, and HR-FABMS analyses. The spectra revealed that in CDCl(3) solution 1 was composed of two rotamers (1a and 1b) in a ratio of approximately 2:1. (C) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2008.03.115

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Echinopines A (1) and B (2), novel sesquiterpenoids with an unprecedented rearranged skeleton named echinopane, were isolated from the roots of Echinops spinosus. The structures were elucidated by extensive spectroscopic analysis. The relative configuration of 1 was assigned by a combination of NOESY correlations and a simulation analysis. A plausible biosynthetic pathway for echinopane was discussed.

DOI： 10.1021/ol702629z

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A novel taxane with an unprecedented hemiacetal ring between C-13 and C-9 was isolated from the needles of Taxus cuspidata. The structure was characterized as (12 alpha H)-2 alpha, 10 beta-diacetoxy-5 alpha-cinnamoyloxy-9 alpha, 13 alpha-epoxytax-4(20)-ene-11 beta, 13 beta-diol (1). This is the first example of a natural taxane with a C-13 and C-9 oxygen bridge to form an unusual 6/8/6/6-membered ring system. (C) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2007.12.045

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/j.bse.2007.05.006

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/j.bse.2007.03.005

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Albizzia plants close their leaves in the evening, as if to sleep, and open them in the morning according to the circadian rhythum. Potassium β-D-glucopyranosyl-12-hydroxyjasmonate was isolated as leaf-closing factor (LCF) of Albizzia saman. We developed molecular probes consisting of modified LCF in order to identify its mode of action. However, it is often discussed whether molecular probes containing a larger and less polar functional unit such as fluorescence dye can bind to genuine binding protein of a natural product in living organisms. So, we need appropriate negative control. And an enantiomer of a biologically active natural product can be used as an ideal control because all physical propaties except for optical rotation and affinity to binding proteins are identical between a pair of enantiomers. Thus, enantio-differential approach that compares the results using a pair of probes that was prepared from a pair of enantiomers would be an ideal method in the bioorganic study using molecular probes. We synthesized probe 11 and biologically inactive enantiomer-type probe 12. And carried out fluorescence labeling study using 11 and 12. The results was clearly shown that the motor cells contain some specific binding protein that can differentiate the stereochemistry of the ligands. Similarly, we synthesized enantio pair-type photoaffinity-labeling probes 20 and 21, and used them for photoaffinity labeling of receptor for LCF. By using protoplast of motor cell, we found 35kDa membrane protein strictly recognizes the stereochemistry of LCF, and it is highly likely that the protein is the specific receptor for LCF.

DOI： 10.24496/tennenyuki.49.0_67

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Synthesis of (-)-tabtoxinine-p-lactam and its (3R)-isomer, the cause of tobacco wildfire disease, was achieved from Lserine using a zinc-mediated coupling reaction, Sharpless asymmetric dihydroxylation and lactainization of beta-mesyloxy benzylhydroxamate amide as the key steps.

DOI： 10.1055/s-2007-983785

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Three novel taxanes with the 10-alkoxy group were isolated from heartwood of Taxus cuspidata. The structures were identified as 2 alpha,14 beta-diacetoxy-10 beta-ethoxytaxa-11,4(20)-dien-5 alpha-ol (1), 2 alpha,14 beta-diacetoxy-10 beta-methoxytaxa-11,4(20)-dien-5 alpha-ol (2), and 2 alpha-acetoxy-10 beta-ethoxytaxa-11,4(20)-diene-5 alpha,14 beta-diol (3) on the basis of spectroscopic analysis. These are the first taxanes with an alkoxy moiety on the skeleton.

DOI： 10.1271/bbb.70210

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Two new taxanes were isolated from the needles of Taxus canadensis. Their structures were established as 10 beta,13 alpha-diacetoxytaxa-4(20),11-diene-5 alpha,9 alpha,14 beta-triol (1) and 4 alpha,13 alpha-diacetoxy-2 alpha,20-epoxy-11(15 -&gt; 1)abeotaxa-11,15-diene-5 alpha,7 beta,9 alpha,10 beta-tetraol (2) on the basis of a spectroscopic analysis.

DOI： 10.1271/bbb.70063

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

A new 2(3 -&gt; 20)abeotaxane with an unusual 13 beta-substitution pattern and a new 6/8/6-ring taxane were isolated from the methanol extract of the needles of Taxus cuspidata. The structures were established as 2 alpha,7 beta-diacetoxy-5 alpha,10 beta,13-trihydroxy-2(3 -&gt; 20)abeotaxa-4(20), 11-dien-9-one (1) and 2 alpha,5 alpha,7 beta,9 alpha,13 alpha-pentahydroxy-10 beta-acetoxytaxa-4(20),11-diene (2) on the basis of 1D and 2D NMR spectral data and high-resolution FAB-MS analyses. Copyright (C) 2007 John Wiley & Sons, Ltd.

DOI： 10.1002/mrc.2001

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A novel taxane with an unprecedented 5/5/4/6/6/6-membered hexacyclic skeleton containing [3.3.2]propellane was isolated from the needles of the Canadian yew, Taxus canadensis. The structure was established as 2 alpha,10 beta-diaectoxy-5 alpha,9 alpha,20 alpha-trihydroxy-3 alpha- 11 alpha;4 alpha, 12 alpha;14 alpha,20-tricyclotaxan-13-one (1), which exists as two conformational isomers on the basis of spectroscopic analysis. This compound would be biogenetically derived from a normal 6/8/6-taxane by the intramolecular aldol reaction and [2+2] cycloaddition. (c) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2007.02.063

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Both enantiomers of cyclopropanated analogues of geraniol, nerol, nor-leaf alcohol, and matsutake alcohol were synthesized and their odor properties evaluated. Odor characters in enantiomeric pairs were similar in the geraniol series. The (+)-(2R,3S)-nerol derivative showed various odor aspects. From the results of nor-leaf alcohol derivatives, an interaction between the (2-re,3-re)-face of nor-leaf alcohol and the human olfactory receptor was suggested. The odor of (3R)-matsutake alcohol derivative was superior to the enantiomer. (c) 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetasy.2007.02.007

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DOI： 10.1002/cbdv.200790070

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DOI： 10.1002/cbdv.200790014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

A new taxoid metabolite with a new substitution pattern was isolated from the methanol extract of the seeds of Taxus mairei, and its structure was established as 5 alpha,15-dihydroxy-7 beta 9 alpha-diacetoxy-11(15 -&gt; 1)abeo-taxa-4(20),11-dien-13-one (1) on the basis of spectral analysis including H-1- and C-13-NMR, HMQC, HMBC, NOESY, and confirmed by HR-FAB mass spectrometry.

DOI： 10.1002/cbdv.200790009

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

The absolute configurations of the enacyloxins, a series of polyhydroxylated polyene antibiotics from Frateuria species, were determined. The so far elusive (13'R,14'R,15'S)-configuration was assigned to enacycloxin IVa (1) by means of 'J-resolved HMBC-1' and NOESY NMR methods.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SOC BRASILEIRA QUIMICA  

A new plant ecdysteroid 7,8 beta-dihydroponasterone A, together with ponasterone A, were isolated from the methanol extract of the needles of the Japanese yew, Taxus cuspidata. Their structures were elucidated on the basis of spectroscopic analysis including H-1 NMR, C-13 NMR, H-1-H-1 COSY, NOESY, HMQC and HMBC and confirmed by high-resolution FABMS data.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

An enantioselective synthesis of the (IS,5R)-enantiomer of litseaverticillols A and B was accomplished in line with our previously reported synthetic pathway for their (M,5S)-enantiomer. The use of "EtSCeCl2" prepared from EtSLi and CeCl3, instead of previously employed EtSLi itself, for the formation of thiol ester intermediates prevented any undesirable epimerization occurring in the process.

DOI： 10.1271/bbb.60253

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(S)-Gizzerosine, a potent inducer of gizzard erosion in chicks, was synthesized using successive zinc-mediated and palladium-catalyzed coupling reactions as the key steps. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2006.07.080

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

DOI： 10.24496/tennenyuki.48.0_361

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Potassium beta-D-glucopyranosyl 12-hydroxyjasmonate (1) is a leaf-closing factor of Albizzia plants that induces nyctinastic leaf closure. In this paper, we synthesized probe 3 and its congener 4 by using a pair of enantiomerically pure methyljasmonate that was prepared by using optical resolution, and carried out fluorescence studies using 3 and 4 to identify the target cell of 1. The probe 3 bound to the motor cells of two Albizzia plants, whereas it could not bind to the motor cells of plants belonging to other genus. On the other hand, probe 4 did not bind to the motor cell at all. These results suggested that a specific receptor for I is involved in the motor cell of Albizzia plants. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2006.06.092

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DOI： 10.24496/intnaturalprod.2006.0__P-37_

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Two new taxoid metabolites were isolated from the methanol extract of the Taxus mairei seeds. Their structures were established as 2 alpha-hydroxy-9 alpha,10 beta,13 alpha-triacetoxy-5 alpha-cinnamoyloxytaxa-11-en-4 beta,20-epoxide (1) and 2'-acetyl taxol (2) on the basis of spectral analysis.

DOI： 10.1080/10286020500172848

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

In this letter, we present our results obtained in attempts to synthesize the initially proposed structure of the spiroketal core of spirofungin B. Based on these results, we propose a reassignment for the structures of the spiroketals obtained by Kiyota's group. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.01.153

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We report the synthesis of the novel fluorescence-labeled jasmonate glycoside 2 based on beta-D-glucopyranosyl 12-hydroxy-jasmonate 1, which is a leaf-closing substance of Albizzia Durazz. The fluorescence study using 2 revealed that the target cell for 1 is a motor cell. Probe 2 bound to the motor cells of two plants belonging to genus Albizzia. This result suggested that a receptor for 2, which is common among genus Albizzia would be involved in the nyctinastic leaf movement. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2006.02.123

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Two new taxanes with a dimethylamino group on the C-5 side chain were identified for the first time in the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 7 beta,10 beta,13 alpha-triacetoxy-5 alpha-(3'-dimethylamino-3'-phenylpropanoyl)- oxy-2 alpha-hydroxy-2(3 -&gt; 20)abeotaxa-4(20),11-dien-9-one (1) and 2 alpha,10 beta-diacetoxy-9 alpha-hydroxy-5 alpha-(3'-dimethylamino-3'-phenylpropanoyl)oxy-3,11-cyclotax-4(20)-en- 13-one (2).

DOI： 10.1271/bbb.70.732

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Four new epoxy taxoids were isolated from the needles of Taxus cuspidata. Their structures were established as 2 alpha,9 alpha-diacetoxy-5 alpha-cinnamoyloxy-11,12-epoxy-10 beta-hydroxytax-4(20)-en-13-one (1), 2 alpha,10 beta-diacetoxy-5 alpha-cinnamoyloxy-11,12-epoxy-9 alpha-hydroxytax-4(20)-en-13-one (2), 2 alpha,9 alpha-diacetoxy-11,12-epoxy-10 beta,20-dihydroxytax-4-en-13-one (3) and 2 alpha,10 beta-diacetoxy-11,12-epoxy-9 alpha,20-dihydroxytax-4-en-13-one (4) on the basis of spectral analysis including H-1-NMR, C-13-NMR, H-1-H-1- COSY, HSQC, HMBC and HRFABMS. Compounds 3 and 4 are the first example of 11,12-epoxy taxoids with C-4 double bond found in T. cuspidata.

DOI： 10.1080/14786410500049426

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：TAYLOR & FRANCIS LTD  

Synthetic studies on bioactive compounds are described, involving phytotoxins (tobacco wildfire disease toxin tabtoxinine-beta-lactam and rice blast disease toxin pyricuol) a glutarimide antibiotic (actiketal) black vomit toxin (gizzerosine) and marine products (antifeedant pteroenone and serinol compound didemniserinolipid).

DOI： 10.1271/bbb.70.317

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

A new paclitaxel derivative and two new 2(3 -&gt; 20)-abeo-taxoids were isolated from a methanol extract of the seeds of Taxus mairei, and their structures were established as 1-deoxypaclitaxel (1), 7 beta,10 beta-diacetoxy-2 alpha,5 alpha,13 alpha-trihydroxy2(3-20)-abeo-taxa-4(20),11-dien-9-one (2), and 2 alpha,13 alpha-diacetoxy-10 beta-hydroxy-2(3 -&gt; 20)-abeo-taxa-4(20),6,11-triene-5,9-dione (3) on the basis of spectroscopic data analysis. Taxane I is the first example of a paclitaxel analogue with a C-1 beta hydrogen substituent. Taxane 3 is an 2(3 -&gt; 20)-abeo-taxane with a rare C-5 ketone and C-6 double bond.

DOI： 10.1021/np0503451

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

A new taxoid was isolated from the methanol extract of the seeds of Taxus mairei. Its structures were established as 2 alpha,9 alpha-diacetoxy-10 beta-hydroxy-5 alpha-cinnamoyloxytaxa- 4(20), 11-dien-13-one (10-deacetyltaxinine, 1) on the basis of spectral analysis including H-1-NMR, C-13-NMR, HMQC, HMBC, NOESY, and HR-FABMS. The structure of previously reported 10-deacetyltaxinine is 9-deacetyltaxinine.

DOI： 10.1080/14786410500111184

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：CHINESE CHEMICAL SOCIETY  

A new abeotaxane was isolated from the seeds of Taxus mairei. Its structure was determined to be 2 alpha, 5 alpha, 13 alpha-trihydroxy-7 beta, 10 beta-diacetoxy-2(3 -&gt; 20) abeotaxa-4(20), 11-dien-9one on the basis of 1D and 2D spectral analysis.

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DOI： 10.1002/cbdv.200690119

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/cbdv.200690041

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Two new taxanes were isolated from the MeOH extract of the needles and branches bark of the Japanese yew, Taxus cuspidata. The structures were established as (2 alpha,5 alpha,7 beta,9 alpha,10 beta,13 alpha)-5,10,13,20-tetraacetoxytax-11-ene-2,7,9-triol(1) and (2 alpha,5 alpha,9 alpha,10 beta)-2,9,10-triacetoxy-5-[(beta-D-glucopyranosyl)oxy]-3,11-cyclotax-11-en-13-one (2) on the basis of in-depth 1D- and 2D-NMR analyses (Tables 1-3, Fig. 1). Compound 2 is the first example of a transannular taxane glycoside isolated from a natural source.

DOI： 10.1002/cbdv.200690117

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Synthesis of both enantionters of methyl 4,5-didehydrojasmonate (1, Delta(4,5)-MJA; &gt; 99.8% ee), a constituent of jasmin absolute, established the absolute configuration of the natural product, and their odor quality was evaluated. The fragrance of the natural (3S,7R)-enantiomer (a fresh natural, sweet floral fruity odor, reminiscent of Jasmin and Ylang Ylang flower, more intensive and tenacious) was superior to that of the unnatural (3R,7S)-enantiomer (a floral green odor with slight metallic green aspect, less intensive than the natural form) and the racemate (green-floral note, having weak and less volume than methyl jasmonate). Odor difference between natural and unnatural enantiomers of methyl jasmonate (2) is also reported.

DOI： 10.1002/cbdv.200690068

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Analogs of aliphatic monoterpene dienols (geraniol, nerol, linalool, and lavandulol) and non-branched alcohols (norleaf alcohol, matsutake alcohol, etc.) bearing a cyclopropane ring were synthesized, and their odor characteristics were examined. Most of the analogs show odor properties different from their parent compounds. © 2006 Verlag Helvetica Chimica Acta AG, Zürich.

DOI： 10.1002/cbdv.200690058

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Gizzerosine, a potent inducer of gizzard erosion in C chicks, was synthesized using successive zinc-mediated and palladium-catalyzed Coupling reactions as the key steps. The piperonyl inoiety was used as a novel N-protecting-1-group.

DOI： 10.1055/s-2005.918447

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The absolute configuration of (-)-pyricuol, a phytotoxin isolated from rice blast disease fungus Magnaporthe grisea, was determined to be R by synthetic studies. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2005.08.099

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The structure of a novel 3,8-seco-bicyclic taxanoid metabolite, isolated from the methanol extract of seeds of the Chinese yew, Taxus mairei, was established as (11 alpha H)-3,8-seco-taxa-3E,7E, 12(18)-triene-2 alpha,6 alpha,9 beta-triol (1) on the basis of spectral analysis including H-1 NMR, C-13 NMR, HMQC, HMBC, NOESY and HR-FABMS. (c) 2005 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2005.07.040

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Enacyloxin IIa methyl ester in non-protic solvent gave rearranged product in acidic conditions such as surface of TLC plate of silica gel or by treatment with a catalytic amount of p-toluenesulfonic acid. On the other hand, such a rearrangement did not occur in polar protic solvent. The structure of the rearranged product was elucidated as 4-acyl analog of the cyclohexane ring.

DOI： 10.1080/14786410412331271997

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

Anew taxane glycoside was isolated from a methanol extract of the needles of Taxus cuspidata. The structure was established as 2 alpha,9 alpha,10 beta-triacetoxytaxa-4(20),11-dien-13-one-5 alpha-O-beta-D-glucopyranoside (1) on the basis of 1D and 2D NMR and high-resolution fast atom bombardment mass spectral analyses. Copyright (c) 2005 John Wiley & Sons, Ltd.

DOI： 10.1002/mrc.1579

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Language：English   Publishing type：Research paper (scientific journal)  

(+)-Pteroenone, a defensive metabolite of the abducted antarctic pteropod Clione antarctica, was firstly and efficiently synthesized by employing anti-selective aldol reaction as the key step.

DOI： 10.1055/s-2005-862389

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The synthesis of the southern (C1'-C11') fragment of pamamycin-635A, isolated from Streptomyces alboniger, was achieved via an Evans aldol reaction, a cis-selective iodoetherification and a stereospecific deiodination as the key steps. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2004.11.067

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：WILEY-V C H VERLAG GMBH  

DOI： 10.1002/cbdv.200590131

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FREUND PUBLISHING HOUSE LTD  

A new taxane-glucoside was isolated from the needles of Taxus cuspidata. The structure was established as 2 alpha,9 alpha,10 beta-triacetoxy-11,12-epoxytax-4(20)-en-13-one-5 alpha-O-beta-D-glucopyranoside (1) on the basis of 1D- and 2D spectral analyses.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VERLAG HELVETICA CHIMICA ACTA AG  

Both enantiomers of lavandulol (1), an important constituent of lavender oil, were prepared by enzymatic optical resolution, and the odor quality of the single antipodes were evaluated. The fragrance of the nature-identical (R)-enantiomer ('weak floral, herbal odor with slightly, lemon-like, fresh citrus fruity nuance') was superior to those of both the unnatural (S)-enantiomer ('very weak odor') and the racemate ('weak floral, herbal odor').

DOI： 10.1002/cbdv.200590088

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A concise and high yielding synthesis of (-)-tabtoxinine-beta-lactam 1, the cause of tobacco wildfire disease, was achieved from L-serine using a zinc-mediated coupling reaction, Sharpless asymmetric dihydroxylation and lactamization of N-OBn amide as the key steps. (C) 2004 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2004.09.033

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Some regulators of plant growth and differentiation have been shown to induce the differentiation of several human myeloid leukemia cells, and might be effective as differentiation inducers to control acute myelogenous leukemia cells. In this study, the growth-inhibiting and differentiation-inducing effects of jasmonates on human myeloid leukemia cells were examined. Several myeloid leukemia cells were cultured with methyl jasmonate (MJ) and its derivatives. Cell differentiation was determined by nitroblue tetrazolium-reducing activity, morphological changes, alpha-naphthyl acetate esterase activity and expression of differentiation-associated surface antigens. MJ induced both monocytic and granulocytic differentiation of HL-60 cells. MJ activated mitogen-activated protein kinase (MAPK) in the cells before causing myelomonocytic differentiation. MAPK activation was necessary for MJ-induced differentiation, since PD98059, an inhibitor of MAPK kinase, suppressed the differentiation induced by MJ. MJ also induced the differentiation of other human leukemia cell lines. Introduction of a double bond at the 4,5-position greatly enhanced the differentiation-inducing activity of MJ. MJ and its derivatives potently induce the differentiation of some myelomonocytic leukemia cells. One novel derivative is a particularly promising therapeutic agent for the treatment of leukemia.

DOI： 10.1038/sj.leu.2403421

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Two new taxoid metabolites, 2alpha,7beta,10beta-triacetoxy-5alpha,13alpha-dihydroxy-2(3--&gt;20)abeotaxa-4(20),11-dien-9-one (1) and 2alpha-acetoxy-5alpha-cinnamoyloxy-9alpha,10beta-dihydroxy-3,11-cyclotax-4(20)-en-13-one (2), were isolated from the methanol extract of needles of the Japanese yew, Taxus cuspidata.

DOI： 10.1271/bbb.68.1584

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Analogs of methyl jasmonate (= methyl (1R*,2R*)-3-oxo-2-[(Z)-pent-2-enyl]cyclopentaneacetate; MJA) bearing a cyclopropane ring, double bond, or a F-substituent were synthesized, and their odor characteristics were examined. Most of the analogs with the same stereochemical properties as methyl epijasmonate showed odor properties superior to MJA. Interestingly, the enol acetate of MIA had a diffusive orchid-like note.

DOI： 10.1002/hlca.200490164

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Tobacco wildfire disease, caused by infection of tobacco wildfire disease fungus Pseudomonas tabaci, has been the most serious pest for tobacco, and tabtoxin (1) was isolated from the fungus as a phytopathogenic toxin. 1 is converted by host plant peptidases to tabtoxinine-β-lactam (2), which inactivates glutamine synthetase irreversibly. 1 can be a selective pesticide when crops resistant to 1 are developed. We began the synthetic studies of 2 to supply samples to its biological tests and to develop an efficient synthetic route. Zinc mediated coupling of iodide 4b with ester 6 and silyl ether 9 gave 10b and 13b, respectively. Sharpless asymmetric dihydroxylation of the double bonds of each compound afforded 19b (20-30%de) and 21b (81-91%de), respectively. The primary hydroxy group of the diol 19b was converted to amino group, and magnesium mediated β-lactam formation and deprotection gave 2. However, the diastereomeric selectivity of the dihydroxylation of 19b had not improved. So, we tried the conversion of 21b. Oxidation of the primary hydroxy group of 21b gave acid 32b. The corresponding benzyloxy amide 33b was converted to mesylate 35b. The key β-lactam formation using NaH afforded 36b. The last deprotection steps are now in progress.

DOI： 10.24496/tennenyuki.45.0_521

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Authorship：Lead author   Language：English   Publishing type：Research paper (bulletin of university, research institution)   Publisher：ROYAL SOC CHEMISTRY  

This review describes research on the chemistry (biosynthesis, metabolism and synthetic analogs) of a plant,hormone, abscisic acid (ABA), covering 1970 to 2002 with 123 references.

DOI： 10.1039/b109859b

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Three novel 4-deacetoxy-1,7-dideoxy azetidine paclitaxel analogues were synthesized through a convenient route that employed hydroboration-amination and intramolecular S(N)2-type substitution reaction from a natural taxoid taxinine. All analogues have been tested for cytotoxicity against three human tumor cell lines. None of them showed remarkable cytotoxicity compared to paclitaxel against tested tumor cell lines. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0960-894X(03)00054-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

Several long-chain aliphatic dienols used as commercial odourants were modified with cyclopropane rings, and their characteristics were examined. We used commercially available (2E, 4E)-2, 4-decadien-l-ol, (3Z, 6Z)-3, 6-nonadien-1-ol, and (2E, 6Z)-2, 6-nonadien-1-ol as parent compounds. Monocyclopropanation of the two double bonds in each compound resulted in a significant increase of odour quality. However, dicyclopropanated analogues lost their original odour quality and intensity. Copyright (C) 2003 John Wiley Sons, Ltd.

DOI： 10.1002/ffj.1171

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Pyricuol, a novel plant pathogen isolated from rice blast disease fungus Magnaporthe grisea, was synthesized as a racemate from 2,3-dimethylphenol using the [2,3]-Wittig rearrangement as the key step.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

2-m-Azidobenzoyl and 2-m-chlorobenzoyl baccatin III analogs were prepared from taxinine, a major component in Japanese yew leaves. In this study, a novel acetyl migration from 13- to 4-hydroxyl group was observed. The antitumor activity of these compounds was evaluated. (C) 2003 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(03)00048-6

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Synthesis of two possible diastereomers of (+)-didemniserinolipid B (1), the first natural serinolipid isolated from a tunicate Didemnum sp., were studied. The known butanediacetal (BDA) protected aldehyde 2 was converted to the core coupling component 8. The serinol fragments (S)-13 and (R)-13 were prepared from D-serine and L-serine, respectively. Wittig-Horner reaction of 8 and (S)-13 gave (4"S)-14, which was converted to ester (4"S)-18. Finally, removal of all the protecting group was achieved in acidic EtOH to afford (30S)-1. Similarly, (30R)-1 was synthesized from (R)-13. However, the ^1H and ^<13>C NMR spectra of the synthetic 1 were different from those of natural 1. In view of the fact that related natural products were sulfated on the serinol unit we therefore believed the 31 position of the natural 1 should be sulfated. Based on this assumption, we investigated further derivatization of the synthetic compounds. We studied sulfation of N-Fmoc derivative (30R)-19, however, with the usual reagents and conditions resulted in only recovery of the starting material. Finally we developed new microwave-assisted sulfation conditions which gave the desired monosulfate, followed by the Fmoc deprotection affording 31-monosulfate (30R)-20. As the ^1H and ^<13>C NMR data and the value of the specific optical rotation of (30R)-20 coincided with those of the natural product, we concluded that the real structure of (+)-didemniserinolipid B corresponded to a 31-sulfate and the absolute configuration was 8R,9R,10R,13S,30S. The microwave-assisted sulfation developed in this process are effective for unreactive hydroxyl groups.

DOI： 10.24496/tennenyuki.44.0_31

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

En route to proving the absolute and relative stereochemistry, through synthesis, of (+)-didemniserinolipid B (1), the first natural serinolipid isolated from a tunicate Didemnum sp., it was discovered that the isolated natural product was in fact the 31-sulfate configured 8R,9R,10R,13S,30S. This structural reassignment was only possible after the development of a microwave-assisted method for the sulfation of unreactive hydroxyl groups.

DOI： 10.1021/ol026421y

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

Analogues of methyl jasmonate bearing a cyclopropane ring were synthesized and their odour characteristics were examined. Cyclopropanation of the pentenyl side chains not only increased the odour intensity, but also gave a mossy mushroom characteristic when compared with the original odour. Modification of the cyclopentanone to fix the cis ring geometry reduced both the quality and intensity of the original odour. Copyright (C) 2002 John Wiley Sons, Ltd.

DOI： 10.1002/ffj.1094

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

A new drimane sesquiterpenoid was isolated from the heartwood of the Japanese yew, Taxus cuspidata Sieb. et Zucc. Its structure was established as 1beta-acetoxyisodrimeninol (1beta-acetoxy-11,12-epoxy-7-drimen-11-ol, 1). This compound was gradually oxidized to give gamma-lactone (1beta-acetoxy-8-drimeno-11,12-lactone, 4).

DOI： 10.1080/1057563029001/4791

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Language：English   Publishing type：Research paper (scientific journal)  

Analogues of leaf alcohol and related compounds, bearing a cyclopropane ring in place of the double bond, were synthesized and their odour characteristics were examined. cis-(Ethylcyclopropyl)ethanol was prepared using the Simmons-Smith reaction with leaf alcohol. Ethoxyethyl ether and some alkyl and aryl esters were also prepared. Cyclopropanation of the double bond modified their original odour characteristic without losing the key green note. Copyright © 2002 John Wiley &amp
Sons, Ltd.

DOI： 10.1002/ffj.1092

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Synthesis of the southern C1'-C11' and eastern C8-C18 fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger, was achieved. The southern fragment was synthesized by using the Evans aldol reaction and cis-selective iodoetherification as the key steps in a 9.6% overall yield (7 steps). The eastern fragment was constructed via the Julia coupling reaction and cis-selective iodoetherification in a 3.0% overall yield (8 steps from the known epoxide).

DOI： 10.1271/bbb.65.2630

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ROYAL SOC CHEMISTRY  

The absolute configuration of the 12',17',18',19'-positions of enacyloxins (ENXs), a series of polyhydroxy-polyenic antibiotics from Frateuria sp. W-315, was determined. As degradation of decarbamoyl (dec) ENX IIa gave (5R,6S,1'E)-6-(but-1'-enyl)-5-chloro-5,6-dihydro-2H-pyran-2-one, which corresponded to the 15'-23' skeleton of dec ENX IIa, its enantiomers were synthesized from tri-O-acetyl-D-glucal. Comparison of the HPLC retention time of these naturally derived and synthetic compounds revealed the 17'R,18'S,19'R-configuration of ENXs; Hydrogenation and oxidation of ENX IIa gave methyl 13-hydroxy-6,12-dimethyltridecanoate, which was converted to the 13-MTPA ester. Comparison of the H-1 NMR chemical shifts and the coupling constants with the model compounds revealed the 12' S-configuration. This absolute stereochemistry is necessarily applicable to other enacyloxins.

DOI： 10.1039/b104341m

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Pamamycins are a series of antibiotic macrodiolides isolated from various Streptomyces species. Among them, pamamycin-607 (1) exhibited aerial mycelium-inducing activity for an aerial mycelium-negative mutant strain and showed antibiotic activity against Gram positive bacteria and fungi. Several synthetic studies including the northern and the southern fragment have been reported to date. In our preliminary communication, we reported the synthesis of the southern fragment (2). In addition, we have also achieved the synthesis of the eastern fragment. Herein we describe the synthetic pathways of these two fragments including experimental details. Synthesis of the southern C1'-C11' and eastern C8-C18 fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger, was achieved. The southern fragment was synthesized by using Evans aldol reaction and cis-selective iodoetherification as the key steps in 9.6% overall yield (7 steps). The eastern fragment was also constructed via Julia coupling reaction and cis-selective iodoetherification in 3.0% overall yield (8 steps from the known epoxide).

DOI： 10.24496/tennenyuki.43.0_521

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Macrotetrolide alpha, a designed analog of polynactin composed of (+)- and (-)-bishomononactic acids, was synthesized. These monomers were prepared via optical resolution of the corresponding (S)-O-acetylmandelates. Assembly of the monomers to macrotetrolide alpha took seven steps without any loss of the intermediates.

DOI： 10.1271/bbb.65.2118

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

The synthesis of methyl (-)-shikimate [(-)-2] was achieved via lipase-catalyzed optical resolution of (1S*, 4R*, 5R*)-4-hydroxy-6-oxabicyclo[3.2.1]oct-2-en-7-one (3). Transesterification of (+/-)-3 and vinyl acetate with lipase MY and subsequent hydrolysis gave optically pure (-)-3. This compound was converted to (-)-2 in two steps.

DOI： 10.1271/bbb.65.2106

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JOHN WILEY & SONS LTD  

Analogues of jasmine lactone and cis-jasmone, bearing cyclopropane rings instead of double bonds, were synthesized and their odour characteristics were examined. Modification of the cyclopentenone ring of cis-jasmone reduced both the quality and the intensity of the original odour. Cyclopropanation of the pentenyl side chains did not increase the odour intensity, but it gave a fruity characteristic to the original odours of cis-jasmone and jasmine lactone. Copyright (C) 2001 John Wiley & Sons, Ltd.

DOI： 10.1002/ffj.974

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Preparation of both enantiomeric methyl jasmonates 1 was achieved via lipase-catalyzed resolution of (+/-)-methyl 7-epicucurbate 3. Lipase P (Amano) provided good selectivity both for acylation of (+/-)-3 (E=370) and hydrolysis of the corresponding acetate (E=41). Resolution of (+/-)-methyl 6,7-diepicucurbate 2 gave poor results. It was found that the (6R,7S)-configuration was suitable for the selective enzymatic reaction and the C-(3) stereochemistry of the substrate did not influence the enzymatic reaction. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0957-4166(01)00169-0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Chemical examination of the seeds of Chinese yew, Taxus yunnanensis Cheng et L, K. Fu resulted in the isolation of an 11(15--&gt;1)abeotaxane, an 11(15--&gt;1), 11(10--&gt;9)bisabeotaxane and two 3,11-cyclotaxanes. The structures of these new taxoids were established as 13 alpha -acetoxy-5 alpha -cinnamoyloxy-11(15--&gt;1)abeotaxa-4(20),11-diene-9 alpha ,10 beta ,15-triol (1), 20-acetoxy-2 alpha -benzoyloxy-4 alpha, 5 alpha, 7 beta, 9 alpha, 13 alpha -pentahydroxy-11(15 --&gt; 1), 11(10 --&gt; 9) bisabeotax-11-eno-10,15-lactone (2), 2 alpha ,10 beta -diacetoxy-5 alpha -cinnamoyloxy-9 alpha -hydroxy-3, 11-cyclotax-4(20)-en-13-one (3) and 10 beta -acetoxy-2 alpha ,5 alpha ,9 alpha -trihydroxy-3,11-cyclotax-4(20)-en-13-one (4) on the basis of spectral analyses.

DOI： 10.1271/bbb.65.35

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PESTICIDE SCI SOC JAPAN  

DOI： 10.1584/jpestics.26.93

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PESTICIDE SCI SOC JAPAN  

DOI： 10.1584/jpestics.26.96

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FREUND PUBLISHING HOUSE LTD  

The stereochemical study of the cyclohexane ring part of enacyloxins (ENXs), a series of antibiotics isolated from Frateuria sp. W-315, was examined. The relative configuration was elucidated by the coupling constant values of the H-1 NMR spectrum. The absolute structure was determined to be 1S, 3R, 4S, because the CD spectrum of the corresponding 3,4-dibenzoate derivative showed negative chirality. This conclusion was confirmed by the synthesis of the dibenzoate from tri-O-acetyl-D-glucal.

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Two new members of enacyloxins (ENXs) were isolated from the culture extract of Frateuria sp. W-315. Spectrometric analyses revealed their structures as decarbamoyl enacyloxin IVa and IIa, the latter preferentially existed in the hemiacetal form. Formation of these compounds were catalyzed by enzymes produced by the fungus. From the coupling constant values of the hemiacetal part of dec ENX IIa, the (17'R*, 18'S*, 19'R*) relative configuration of ENXs was also elucidated.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PESTICIDE SCI SOC JAPAN  

Synthesis of the diastereomers of (+)-altholactone, an antitumor acetogenin from various Goniothalamus species, was achieved. Four isomers including 3a,7a-trans-fused analogs were synthesized from 2,3-O-cyclohexylidene-D-glyceraldehyde via twice separation of diastereomers.

DOI： 10.1584/jpestics.26.361

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Both enantiomers of altholactone, isoaltholactone and 5-hydroxygoniothalamin were synthesized from tri-O-acetyl-D-glucal. and biological activities of altholactones were examined, For brine shrimp. the configuration or 3-hydroxy group at convex site was important for lethal activity. while (2S,3S)-configuration was inhibitory to lettuce germination.

DOI： 10.1584/jpestics.26.366

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：HARWOOD ACAD PUBL GMBH  

Three new taxane diterpenoids were isolated from the leaves of the Japanese yew, Taxus cuspidta. Their structures were established as 5 alpha ,13 alpha -diacetoxy-taxa-4(20),11-diene-9 alpha ,10 beta -diol (1), 7 beta ,13 alpha -diacetoxy-5 alpha -cinnamyloxy-2(3--&gt;20)-abeo-taxa-4(20), 11-diene-2 alpha ,10 beta -diol (2), and 2 alpha ,10 beta ,13 alpha -triacetoxy-taxa-4(20),11-diene-5 alpha ,7 beta ,9 alpha -triol (3)respectively on the basis of 1D and 2D NMR data.

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Language：Japanese   Publisher：Symposium on the chemistry of natural products  

Currently, diterpenoid paclitaxel (faxol^[○!R] 1) is regarded as a powerful therapeutic drug for cancer chemotherapy. 1 exhibits potent antitumor activity against various cancers that have been ineffectively treated by existing chemotherapeutic drugs, and 1 have been approved by the FDA for the treatment of advanced ovarian cancer and breast cancer. Recent studies have shown that treatment for various types of advanced solid cancers with paclitaxel and docetaxel often insults in the emergence of multi-drug resistance (MDR). Thus, it is important to explore new taxoids either with improved activity against various classes of tumors, especially against drug-resistant human cancers. Here we report the methods to convert taxinine, abundantly available from the Japanese yew leaves, to a new 2-m-azido-1,7-deoxybaccatin III analog,which would be an active substrate for the tublin depolymerization test as well as 1. We also report that the biomimetic hydroxylation of C-1 position of 2-deacetoxy-taxinine J derivative (2d) had been successfully achieved by a simple chemical oxidation using dimethyl-dioxirane (DMDO), leading to the 1β-hydroxy-4α, 20-epoxide (26) and its 4β-isomer (27). This method could not be applied for 2-acetoxy-taxoids. In addition, it was found that the change of reaction temperature could control the regioselectivity of the epoxidation between the endo- and exo-double bonds of 2-deacetoxytaxinine J (2d) with m-CPBA. Attempts of biomimetic construction of the D-ring of taxol from the 4 β, 20-epoxy-5-mesyl taxoids (17) with Lewis acid mediated reaction were unsuccessful. While the same condition could convert 22-bromo-4 β, 5β-epoxy taxoid (20) to 4, 22-spirotaxoids (21) as a sole product. These result suggest that the nucleophilic trap of carbocation (III) at 5-position by water would be prior to that at 4-position, that is, it is difficult to demonstrate the proposed biosynthetic pathway of D-ring by a synthetic method.

DOI： 10.24496/tennenyuki.42.0_745

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Four stereoisomers of streptimidone (1), an antibiotic from Streptomyces rimosus forma paromomycinus, were synthesized from methyl (S)-3-hydroxy-2-methylpropanoate. The natural diastereomer 1 shows the strongest antimicrobial activity.

DOI： 10.1002/1099-0690(200010)2000:20<3459::AID-EJOC3459>3.0.CO;2-F

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The principal constituents of iris oil, (-)-cis-alpha -irone and (-)-cis-gamma -irone, and their enantiomers, were synthesized from (-)- and (+)-2,2,4-trimethyl-3-cyclohexene-1-carboxylic acids. The racemic acid was resolved by recrystallization of its salt with a chiral amine, or by enzymatic hydrolysis of the corresponding alcohol. The fragrances of (-)-(1R,SS)-cis-alpha -irone and (-)-(1R,SS)-cis-gamma -irone were superior to those of (+)-(1S,5R)-cis-alpha -irone and (+)-(1S,5R)-cis-gamma -irone. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0957-4166(00)00345-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE SOC SOIL SCIENCE PLANT NUTRITION  

Effects of fertilizer and manure application on L-glutaminase and L-asparaginase activities on volcanic ash soil and gray lowland soil mere examined. The activities were estimated by using the indophenol method. This involved the colorimetric estimation of NH4+ released from L-glutamine or L-asparagine catalyzed by the enzymes, when the soils were incubated with 0.25 M L-glutamine or L-asparagine in 0.1 M phosphate buffer (pH 7.6) and toluene used as a germicide, Both L-glutaminase and L-asparagine activities were the largest in the farmyard manure plot (OM), followed by the chemical fertilizer plot (CF) and the plot without fertilizer application, hereafter referred to as "no fertilizer plot" (NF).

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

The synthesis of (+/-)-methyl bishomononactate, one of the monomeric components of polynactin antibiotics (macrotetrolides), was achieved via cis-selective iodoetherification as the key step.

DOI： 10.1271/bbb.64.1671

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Chemical examination of the seeds of the Chinese yew, Taxus yunnanensis Cheng et L. K. Fu and the Japanese yew, Taxus cuspidata Sieb et Zucc, resulted in the isolation of four taxane diterpenoids. The structures of these taxoids were established as (12 alpha)-2 alpha-acetoxy-5 alpha,9 alpha,10 beta-trihydroxy-3,11-cyclotax-4(20)-en-13-one; 2 alpha,7 beta,13 alpha-triacetoxy-5 alpha,9 alpha-dihydroxy-2(3 --&gt; 20)abeotaxa-4(20),11-dien-10-one; 9 alpha,10 beta-diacetoxy-5 alpha-cinnamoyloxytaxa-4(20),11-dien-13 alpha-ol and the known 2 alpha,7 beta,9 alpha,10 beta,13-pentaacetoxytaxa-4(20),12-diene-5 alpha,11 beta-diol on the basis of spectral analysis. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0031-9422(00)00186-2

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The first synthesis of actiketal (RK-441S), an antibiotic fi-om Streptomyces pulveraceus subsp. epiderstagenes, was achieved from 5,7-dimethylbenzofuran and dimethyl glutaconate via palladium-assisted coupling reaction as a key step. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)00928-X

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Lipase-catalyzed optical resolution of (+/-)-epoxy-beta-cyclogeraniol (1), a key synthetic intermediate for epoxy-beta-ionylideneacetic acid, was achieved in high enantiomeric purity. Transesterification with vinyl acetate by using lipase P (Nagase) made enriched (-)-1, while hydrolysis of the corresponding acetate by using lipase P (Amano) afforded (+)-1 with a high E value (E = 1600).

DOI： 10.1271/bbb.64.1444

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The C9-C20 spiroacetal parts of spirofungin A and B, antifungal antibiotics from Strephomyces violaceusniger Tu 4113, were synthesized simultaneously from (S)-citronellyl bromide and (+/-)-epoxy alcohol via alkyne-lactone coupling reaction and diastereomeric separation. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)00371-3

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FREUND PUBLISHING HOUSE LTD  

Unnatural enantiomer of a dilactone antibiotic (-)-antimycin A(3) and its deformylamidodehydroxy analog were synthesized using chelation controlled alkylation as a key step. (-)-Antimycin A(3) and its analog hardly showed antimicrobial activity compared with natural antimycin A complex. The formal synthesis of natural (+)-antimycin A(3) is also achieved.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：FREUND PUBLISHING HOUSE LTD  

Synthesis of the southern (C1'-C11') part of pamamycin-607, an aerial mycelium-inducing substance for Streptomyces alboniger, was achieved via Evans aldol reaction and cis-selective iodoetherification as the key steps.

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Methyl esters of (+/-)-tuberonic acid and (+/-)-12-hydroxyjasmonic acid (trans-tuberonic acid), the aglycons of strong potato tuber-forming substances, were synthesized from norbornene via side-chain elongation and Baeyer-Villiger oxidation as hey steps.

DOI： 10.1271/bbb.63.2110

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Preparation of both the enantiomers of 4-hydroxy-2,6,6-trimethyl-2-cyclohexen-1-one (phorenol), which are versatile synthetic intermediates for abscisic acid and carotenoids, was achieved by hydrolase-catalyzed hydrolysis of the corresponding chloroacetate. The hydrolysis with esterase SNSM-87 (Nagase) enriched the (S)-ester, while lipase P (Amano) afforded the (R)-ester. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0957-4166(99)00391-2

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Enantioselective synthesis of dendryphiellin C, isolated from cultures of Dendryphiella sarina, has been achieved in a convergent way such as coupling of a C9-branched carboxylic acid 10 with a trinor-eremophilane alcohol 11. The latter was synthesized starting from a chiral building block, (1S,5S,6R)-5-hydroxybicyclo[4.1.0]heptan-2-one 16, which was originally prepared in this group using biochemical transformation as a key step. The synthesis was completed through 12 steps from 16 in overall 2.4% yield. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4020(99)00407-X

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Three new rearranged taxane diterpenoids with 5/7/6-membered ring system were isolated from the bark of Taxus chinensis var, mairei (1 and 2) and the needles of T. cuspidata (3). The structures of them were established as 2 alpha,7 beta-diacetoxy-5 alpha, 10 beta, 13 alpha, 15-tetrahydroxy-4 beta (20)-epoxy-9 alpha-benzoyloxy 11(15--&gt;1)abeotax-11-ene (1), 2 alpha,4 alpha-diacetoxy-7 beta-benzoyloxy-5 beta,20-epox 10 beta, 13 alpha,15-tetrahydroxy-11 (15--&gt;1)abeotax-11-ene (2), and 4 alpha, 7 beta-diacetoxy-2 alpha-benzoyloxy-5 beta,20-epoxy-9 alpha, 10 beta, 13 alpha, 15-tetrahydroxy-11(15--&gt;1)abeotax-11-ene (3) on the basis of spectral data including 2D NMR spectroscopies.

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Language：English   Publisher：GEORG THIEME VERLAG  

Two bicyclic taxanes and two abeotaxanes were isolated from the bark and the needles of the Chinese yew, Taxus chinensis var. mairei. Thestructures of the two new compounds, 5-(N,N-dimethyl-3'-phenylisoseryl)taxachitriene A and 13-acetyl-9-deacetyl-9-benzoyl-10-debenzoyltaxchinin A, were established by spectral methods.

DOI： 10.1055/s-2006-957580

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：AMER CHEMICAL SOC  

Three novel (1-3) and five known bicyclic 3,8-secotaxane diterpenoids were isolated from the needles of the Chinese yew, Taxus chinensis var, mairei. The structures of the new compounds were established, respectively, as (3E,7E)-2 alpha,10 beta,13 alpha-triacetoxy-5 alpha,20-dihydroxy-3,8-11-trien-9-one (1), (3E,7E)-2 alpha, 10 beta-diacetoxy-5 alpha,13 alpha,20-trihydroxy-3,8-secotaxa-3,7,11-trien-9-one (2), and (3E,8E)-7 beta,9,10 beta,13 alpha,20-pentaacetoxy-3,8-secotaxa-3,8,11-triene-2 alpha,5 alpha-diol (2-deacetyltaxachitriene A) (3), on the basis of spectral analysis. The other five bicyclic taxane diterpenoids were determined as canadensene, 6-deacetyltaxachitriene B, taxachitriene B, taxuspine U, and taxuspine X by comparison of their physical properties and spectral data with those previously reported.

DOI： 10.1021/np980213q

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：HARWOOD ACAD PUBL GMBH  

A new 11(15--&gt;1)-abeotaxane diterpenoid (1) along with 11 known taxoids were isolated from the bark of the Chinese yew, Taxus mairei, and the structure was established as 9-deacetyl-9-benzoyl-10-debenzoyl-5-cinnamoyl-taxchinin A on the basis of 1D and 2D NMR data.

DOI： 10.1080/10575639808048873

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

A new taxane, 14beta-hydroxytaxusin (1), was isolated from the bark of the Chinese yew, Taxus mairei.

DOI： 10.1080/10575639808048274

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Methyl 3,7-didehydrojasmonate was synthesized as an analogue of methyl epijasmonate. This analogue inhibited the germination of lettuce seed more strongly than methyl jasmonate. Methyl 4,5-didehydrojasmonate was also synthesized and its biological activities were comparable to those of methyl jasmonate. (C) 1997 Elsevier Science Ltd.

DOI： 10.1016/S0031-9422(97)00374-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG  

(+)-Homononactic acid, one of the monomers of polynactin, and its 8-epimer were synthesized. The key step was cis-selective iodoetherification of the enone or the alpha-silyloxyolefin intermediates constructed with Wittig-Horner or Julia coupling reactions, respectively.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG  

Chlorosulfonic acid catalyzed cyclization reaction of beta-monocyclonerolidol and beta-monocyclofarnesol and corresponding acetates gave a unique rearranged product (2S*, 3S*, 4aR*, 8aS*)-1,3,4,5,6,7,8,8a-octahydro-2,5,5,8a-tetramethyl-2H-2,4a-methanonaphthalen-3-ol, the structure of which was elucidated by X-ray analysis.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG  

(+/-)-Homononactic acid and its 8-epimer were synthesized by using cis-selective iodoetherification as the key step.

DOI： 10.1055/s-1996-5536

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Methyl 5',5',5'-trifluorojasmonate was synthesized as an antimetabolic analogue of methyl jasmonate. It induced potato tuber formation more effectively than methyl jasmonate and inhibited the growth of rice seedlings and the germination of lettuce and radish seeds. These results suggest that epijasmonic acid itself has potato tuber-inducing activity and that the hydroxyl group of tuberonic acid is not necessary for this activity.

DOI： 10.1016/0031-9422(96)00145-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS LTD  

Abscisic acid (ABA) is easily isomerized to inactive fl arts-ABA It light, To solve this problem, two variations of epoxy-beta-ionylideneacetic acid were synthesized as ABA analogs, each of them having a methoxycarbonyl or a fluoric substituent at the 2-position. The 2E-, and 2Z-fluorinated analogs showed moderate growth inhibitory activity toward rice seedlings and lettuce seeds, whereas the methoxycarbonyl analog was inactive toward rice seedling growth and only partially active toward lettuce germination, The 2E-fluorinated analog was extensively isomerized to the 2Z-isomer bg UV irradiation, We think that a steric requisite for the 2E-position was high, and that the fluorine substituent was not effective for fixing the 2-double bond in the E-configuration.

DOI： 10.1271/bbb.60.1076

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE SOC SOIL SCIENCE PLANT NUTRITION  

A simple and rapid method was developed for determining L-glutaminase and L-asparaginase activities in soils. It involved colorimetric estimation of NH4+ released by the activity of L-glutaminase and L-asparaginase when soil was incubated with 0.25 M L-glutamine or L-asparagine in 0.1 M phosphate buffer (pH 7.6) and toluene used as a germicide.
The indophenol method was applied to the assay of NH4+ for soil L-glutaminase and L-asparaginase activities. Color development in the indophenol method required one hour. The color development was stable for 2 d and was not appreciably affected by the presence of L-glutamine, L-glutamic acid, L-asparagine, and L-aspartic acid. In addition, no turbidity nor precipitate appeared in the presence of a high concentration (10 mu g) of NH4+-N. The L-glutaminase activity was estimated in three soil samples differing in pH, organic-C content, and land use. The L-glutaminase activity in the three soils ranged from 28 to 1,470 mU (10(-9) mol min(-1) g(-1) of dry soil at 30 degrees C). The optimum pH for the L-glutaminase activity in soils was about 7.5 in phosphate buffer.
The incubation time of L-glutaminase and L-asparaginase can be shortened, because the sensitivity of the indophenol method is about 24 times as high as that of the Nessler method.

DOI： 10.1080/00380768.1995.10419587

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：VCH PUBLISHERS INC  

(3S,7R,8E,10E)-3,7,9-Trimethyl-8,10-dodecadien-6-one (1), the major component of the female-produced sex pheromone of the maritime pine scale (Matsucoccus feytaudi), was synthesized by starting from epoxide 2, which was obtained from meso-epoxy diacetate (F) by employing enzyme-catalyzed asymmetric hydrolysis as the key step.

DOI： 10.1002/jlac.199419941003

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An efficient two-step procedure to prepare conjugated dienes from allylic alcohols is developed without the formation of regioisomers and rearranged products.

DOI： 10.1055/s-1994-25548

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(2S,4R,5S)-2,4,6-Trimethyl-5-heptanolide (1), a ses pheromone component for Macrocentrus grandii, aas synthesized by starting from methyl (R)-citronellate (2) and employing bromolactonization (10--&gt;11) as the key reaction.

DOI： 10.1271/bbb.58.1120

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Language：Japanese   Publishing type：Meeting report   Publisher：Pesticide Science Society of Japan  

DOI： 10.1584/jpestics.W19-13

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DOI： 10.1584/jpestics.W18-15

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DOI： 10.1584/jpestics.W17-42

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DOI： 10.1271/kagakutoseibutsu.50.67

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