Authorship：Last author,　Corresponding author   Language：English   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)   Publisher：American Chemical Society (ACS)  

DOI： 10.1021/acs.joc.0c00965

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)   Publisher：The Japan Institute of Heterocyclic Chemistry  

DOI： 10.3987/rev-20-929

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Language：Japanese   Publishing type：Article, review, commentary, editorial, etc. (scientific journal)  

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Language：English   Publisher：American Chemical Society  

The ruthenium(II)-catalyzed C-H aminocarbonylation of N-(hetero)aryl-7-azaindoles with isocyanates is described. The excellent site selectivity at the ortho-position within the N-(hetero)aryl ring was observed to provide ortho-amidated N-(hetero)aryl-7-azaindoles under the mild reaction conditions. The resulting 7-azaindole derivatives can be readily transformed into 7-azaindoles containing carboxylic acid and alkyl amine functional groups.

DOI： 10.1021/acs.joc.8b00388

Scopus

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Language：English  

BACKGROUND: Aging induces cardiac structural and functional changes linked to the increased deposition of extracellular matrix proteins, including OPN (osteopontin), conducing to progressive interstitial fibrosis. Although OPN is involved in various pathological conditions, its role in myocardial aging remains unknown. METHODS: OPN deficient mice (OPN-/-) with their wild-type (WT) littermates were evaluated at 2 and 14 months of age in terms of cardiac structure, function, histology and key molecular markers. OPN expression was determined by reverse-transcription polymerase chain reaction, immunoblot and immunofluorescence. Luminex assays were performed to screen plasma samples for various cytokines/adipokines in addition to OPN. Similar explorations were conducted in aged WT mice after surgical removal of visceral adipose tissue (VAT) or treatment with a small-molecule OPN inhibitor agelastatin A. Primary WT fibroblasts were incubated with plasma from aged WT and OPN-/- mice, and evaluated for senescence (senescence-associated β-galactosidase and p16), as well as fibroblast activation markers (Acta2 and Fn1). RESULTS: Plasma OPN levels increased in WT mice during aging, with VAT showing the strongest OPN induction contrasting with myocardium that did not express OPN. VAT removal in aged WT mice restored cardiac function and decreased myocardial fibrosis in addition to a substantial reduction of circulating OPN and transforming growth factor β levels. OPN deficiency provided a comparable protection against age-related cardiac fibrosis and dysfunction. Intriguingly, a strong induction of senescence in cardiac fibroblasts was observed in both VAT removal and OPN-/- mice. The addition of plasma from aged OPN-/- mice to cultures of primary cardiac fibroblasts induced senescence and reduced their activation (compared to aged WT plasma). Finally, Agelastatin A treatment of aged WT mice fully reversed age-related myocardial fibrosis and dysfunction. CONCLUSIONS: During aging, VAT represents the main source of OPN and alters heart structure and function via its profibrotic secretome. As a proof-of-concept, interventions targeting OPN, such as VAT removal and OPN deficiency, rescued the heart and induced a selective modulation of fibroblast senescence. Our work uncovers OPN's role in the context of myocardial aging and proposes OPN as a potential new therapeutic target for a healthy cardiac aging.

DOI： 10.1161/CIRCULATIONAHA.117.031358

PubMed

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DOI： 10.1039/C8CC05697H

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Language：English   Publisher：Public Library of Science  

Excessive levels of reactive oxygen species (ROS) and impaired Ca2+ homeostasis play central roles in the development of multiple cardiac pathologies, including cell death during ischemia-reperfusion (I/R) injury. In several organs, treatment with 2-aminoethoxydiphenyl borate (2-APB) was shown to have protective effects, generally believed to be due to Ca2+ channel inhibition. However, the mechanism of 2-APB-induced cardioprotection has not been fully investigated. Herein we investigated the protective effects of 2-APB treatment against cardiac pathogenesis and deciphered the underlying mechanisms. In neonatal rat cardiomyocytes, treatment with 2-APB was shown to prevent hydrogen peroxide (H2O2) -induced cell death by inhibiting the increase in intracellular Ca2+ levels. However, no 2-APB-sensitive channel blocker inhibited H2O2-induced cell death and a direct reaction between 2-APB and H2O2 was detected by 1H-NMR, suggesting that 2-APB chemically scavenges extracellular ROS and provides cytoprotection. In a mouse I/R model, treatment with 2-APB led to a considerable reduction in the infarct size after I/R, which was accompanied by the reduction in ROS levels and neutrophil infiltration, indicating that the anti-oxidative properties of 2-APB plays an important role in the prevention of I/R injury in vivo as well. Taken together, present results indicate that 2-APB treatment induces cardioprotection and prevents ROS-induced cardiomyocyte death, at least partially, by the direct scavenging of extracellular ROS. Therefore, administration of 2-APB may represent a promising therapeutic strategy for the treatment of ROS-related cardiac pathology including I/R injury.

DOI： 10.1371/journal.pone.0189948

Scopus

PubMed

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Language：English   Publisher：AMER CHEMICAL SOC  

The dienone-phenol rearrangement is a useful tool for the synthesis of highly substituted phenols. In our previous study of the rearrangement of 4,4-disubstituted 2-hydroxycyclohexa-2,5-dienone under deoxyfluorination conditions, bond migration proceeded with very poor regioselectivity. In this paper, an acid-mediated rearrangement, of O-perfluoroalkylsulfonyl difluorides with regioselective migration toward the beta'-carbon is reported. This method allowed the synthesis of a fluorinated analog of allocolchicinoids with improved total yield. Successful application to other substrates was also demonstrated.

DOI： 10.1021/acs.joc.7b02208

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Language：English   Publisher：TAYLOR & FRANCIS LTD  

Agelastatins are a family of tetracyclic alkaloids isolated from marine sponges. The patent examined in this publication covers the chemical synthesis of agelastatins A to F and eight analogues and their therapeutic use against hematologic malignancies. The claim on the chemical synthesis features a novel biomimetic cyclization of a tricyclic precursor, which streamlines scalable access to agelastatins and their analogues. This new synthetic approach can potentially expedite the research on these compounds for therapeutic use against cancers by making them more easily available. The claim on the therapeutic use against hematologic malignancies is based on the in vitro cytotoxicity against a limited number of cell lines and can be further strengthened by in vivo therapeutic evaluations focusing on specific hematologic malignancies. The comparative evaluation of the cytotoxicities of the natural alkaloids described in the application greatly enhances the understanding of their structure-activity relationships (SARs) relevant to the development of novel medicinal leads. Overall, the patent application is strong and has the potential to advance the rapidly expanding agelastatin research.

DOI： 10.1080/13543776.2017.1273902

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Language：Japanese   Publishing type：Book review, literature introduction, etc.   Publisher：SOC SYNTHETIC ORGANIC CHEM JPN  

The present article discusses our recent endeavors on natural product syntheses wherein radical reactions are strategically employed to access fused carbocycles. Particular emphasis is placed on the radical cyclizations that made it possible to establish the unique bond connectivity and functionalities of the target natural products. The radical chemistry-based approaches to platencin and clavilactone B are discussed here to show the utility of titanocene (III)-mediated epoxy enone cyclization, decarboxylative radical cyclization of an alkynyl carboxylic acid derivative with lead (IV) in 1,4-dioxane, and samarium (II)-mediated radical cyclization-fragmentation of an unsaturated keto ester, all of which serve as versatile means to elaborate the natural products.

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

Allocolchicinoids, with a distinct polyoxygenated dibenzocycloheptane skeleton, attract much attention as potential candidate anticancer drugs. In this study, eight C-ring fluorinated analogues of allocolchicinoids, seven C-ring oxygen-substituted analogues, and known compounds N-acetylcolchinol and NSC 51046 were synthesized as racemates from a single common intermediate by using either the deoxyfluorination/migration domino reaction or acid-promoted migration as the key step. Among the products obtained, some of the fluorinated derivatives strongly inhibited the growth of prostate DU145 and pancreas Panc 1 cancer cell lines with efficacy comparable to or better than those of N-acetylcolchinol and NSC 51046. They were also less toxic against a non-cancerous cell line than the known compounds were.

DOI： 10.1002/ejoc.201501624

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DOI： 10.5059/yukigoseikyokaishi.74.350

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Language：English   Publisher：AMER CHEMICAL SOC  

A new synthetic route to clavilactone B, a naturally occurring inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, is disclosed. The route features a sequential samarium-mediated radical cyclization-fragmentation of an indanone derivative, which provides rapid access to a 10-membered carbocyclic motif fused to an aromatic ring.

DOI： 10.1021/ol503356m

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

A facile enantiospecific approach to (+)-ligudentatol (1) and (-)-ligudentatol (ent-1) is reported. The approach features the construction of a trisubstituted phenolic motif fused to a chiral aliphatic ring by a sequence of visible-light-mediated radical seleno transfer cyclization, bromination, concomitant selenoxide elimination-dehydrobromination, and demethoxycarbonylation, namely, a programmed aromatization. Biological evaluation of the enantiomers of ligudentatol obtained by the present route revealed for the first time their cytotoxicity towards various cancer cell lines.

DOI： 10.1002/asia.201400110

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

Free radicals, which in the past were considered unruly chemical species, have become manageable and indispensable for synthetic organic chemistry. The unique nature of free radicals has allowed practitioners in organic synthesis to design flexible approaches to produce various materials ranging from small molecules to polymers. The present Personal Account describes the author's endeavors to create molecular complexity by the strategic use of free radicals, with an emphasis on the synthesis of bioactive natural products.

DOI： 10.1002/tcr.201300024

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

A new approach to platencin, a potent antibiotic isolated from Streptomyces platensis, has been established. The highly congested tricyclic core of the natural product was successfully constructed by decarboxylative radical cyclization of an alkynyl silyl ester with Pb(OAc)(4) in the presence of pyridine in refluxing 1,4-dioxane. The key decarboxylation, which likely takes place via lead(IV) esterification followed by carbon-centered radical generation and subsequent capture of the radical with a triple bond, allows the rapid construction of the twisted polycyclic system.

DOI： 10.1039/c4cc07316a

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

(-)-Agelastatin A (AA), isolated from the coral sea axinellid sponge Agelas dendromorpha, has shown a high antineoplastic activity. We have synthesized eighteen AA analogues and analyzed their cytotoxicities towards three cancer cell lines. By the structure-activity relationship (SAR) study, we identified three novel analogues with higher or comparable cytotoxic activities to AA. They were subjected to chemoinformatic analysis, which revealed physicochemical properties favoring excellent central nervous system (CNS) penetration. CNS pharmacokinetic analysis in murine models validated the chemoinformatic prediction and revealed that these analogues indeed had better CNS penetration than AA. These novel potent AA analogues deserve further evaluation for therapeutic use against cancers, particularly primary and secondary brain tumors.

DOI： 10.1039/c3md00094j

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Language：English   Publisher：BEILSTEIN-INSTITUT  

An iron(II)-mediated aminohalogenation of a cyclopentenyl N-tosyloxycarbamate provided new access to the key intermediate for the synthesis of (-)-agelastatin A (AA, 1), a potent antiproliferative alkaloid. The present synthetic endeavour offered an insight into the mechanism underlying the iron(II)-mediated aminohalogenation of N-tosyloxycarbamate, in which the radical properties of the N-iron intermediates in the redox states were operative.

DOI： 10.3762/bjoc.9.99

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Language：English   Publisher：ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER  

Five novel hybrid molecules of annonaceous acetogenins and insecticides targeting mitochondrial complex I were synthesized and their growth inhibitory activities against 39 human cancer cell lines were investigated. It was revealed that the connecting group between the N-methylpyrazole part and the hydrophobic alkyl chain bearing the THF ring influenced their biological activities significantly. Amide-connected analog 2, in particular, showed selective and very potent activity (<10 nM) against some cancer cell lines. (C) 2013 Elsevier Masson SAS. All rights reserved.

DOI： 10.1016/j.ejmech.2013.03.009

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

The potent antimycobacterial activity of (+/-)-platencin is reported. Complete inhibition of Mycobacterium smegmatis growth was observed at MICs of 0.5 mu g mL(-1) and 0.3 mu g mL(-1) under aerobic and hypoxic conditions, respectively. Notably, the compound exhibited potent bacteriostatic activities towards Mycobacterium tuberculosis H37Rv (MIC = 2 mu g mL(-1)), multi-drug-resistant M. tuberculosis (MIC = 1 mu g mL(-1)), and extensively drug-resistant M. tuberculosis (MIC = 1 mu g mL(-1)). An overexpression study of the transformants of M. smegmatis revealed that platencin selectively targeted Mt-KasB and modestly inhibited Mt-KasA and Mt-FabH.

DOI： 10.1039/c3md00016h

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

A 2 : 1 mixture of NCS and Ph3P successfully promoted the anti-dichlorination of olefins to provide corresponding dichlorides, serving as a molecular chlorine surrogate generated in situ.

DOI： 10.1039/c3ob27345h

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Language：English   Publisher：WILEY-V C H VERLAG GMBH  

Palladium-catalyzed cascade C?H alkenylation and arylation provides convenient access to polycyclic aromatic compounds. Treatment of 3-bromoaniline derivatives bearing a bromocinnamyl group on the nitrogen atom with a catalytic amount of [Pd(OAc)2] and PCy3 center dot HBF4 in the presence of Cs2CO3 in dioxane affords naphthalene-fused indole derivatives in good yields. This double cyclization reaction is also applicable to heterocyclic substrates, giving fused indoles containing a heteroaromatic ring such as dibenzofuran, dibenzothiophene, carbazole, indole, or benzofuran through heterocyclic C-H arylation. When using a 2,6-unsubstituted aniline derivative, the first C-H arylation preferentially proceeds at the more hindered position of the aniline ring.

DOI： 10.1002/chem.201103819

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

Agelastatin A (AA) is an anti-neoplastic agent with anti-osteopontin (OPN) activity. Brain tumors often express OPN significantly. A comprehensive chemoinformatic analysis followed by in vivo pharmacokinetic evaluations in mice is performed. CNS penetration of AA is about 10%. AA should be further tested for activity against brain tumors.

DOI： 10.1039/c1md00240f

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Language：English   Publisher：AMER CHEMICAL SOC  

The alkylation of dienolates generated from 3-methoxycycloalk-2-enones having a 3'-hydroxyl alkenyl chain provides the corresponding quaternized cycloalkenones in a highly diastereoselective manner. The high degree of stereocontrol in the alpha-quaternization possibly implies intervention of a rigid chelating transition state that allows an efficient 1,4-asymmetric induction to take place.

DOI： 10.1021/jo2022789

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

A stereoconvergent access to chiral carbocyclic building blocks is reported. 6-(3'-Hydroxy-4'-methylpent-4'-enyl)-3-methoxy cyclohex-2-enone (1) that consists of four stereoisomers, i.e., racemic ca. 1:1 diastereomers, is converted to enantiomerically pure carbocycles through a combination of regioselective catalytic asymmetric reduction and alkylative remote stereoinduction. The present stereoconvergent strategy has allowed the formal synthesis of bioactive (-)-dysidiolide.

DOI： 10.1039/c2ob26532j

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

Allyl N-tosyloxycarbamates are found to be catalytically transformed into beta-brominated oxazolidinones with FeBr2/n-Bu4NBr in t-BuOH.

DOI： 10.1039/c2ob07190h

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The convergent synthesis of C35-fluorinated analogues of solamin, a mono-THF Annonaceous acetogenin, has been achieved by the Sonogashira coupling of the THF ring fragment and the fluorinated gamma-lactone fragment. It was revealed that the number of fluorine atoms on the gamma-lactone moiety affects the growth inhibitory activities against human cancer cell lines. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.bmcl.2011.08.011

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Language：English   Publisher：AMER CHEMICAL SOC  

A novel route to (+/-)-platencin is reported, in which the highly stereoselective alkylative quaternization of a cyclohexenone scaffold via 1,4-diastereoinduction and two radical carbon carbon bond-forming reactions that involve titanium(III)-mediated cyclization and stannyl-radical-mediated skeletal rearrangement are utilized.

DOI： 10.1021/ol2013439

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Language：English   Publisher：AMER CHEMICAL SOC  

A novel photochemical C-H carbamoylation of an octahydroisolndole derivative with PhNCO has allowed the authors to provide a unique access to a highly functionalized proline motif from which total synthesis of (+/-)-kainic acid, a bioactive marine alkaloid, has been accomplished.

DOI： 10.1021/ol200772f

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Language：English   Publisher：AMER CHEMICAL SOC  

A convergent asymmetric total synthesis of (+)-danicalipin A is accomplished, in which two chlorinated fragments are stereoselectively joined by 1,3-dipolar coupling, leading to the confirmation of the absolute configuration of the natural product.

DOI： 10.1021/ol1029518

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The convergent synthesis of fluorescence-labeled solamin, an antitumor Annonaceous acetogenin, was accomplished by two asymmetric alkynylations of 2,5-diformyl tetrahydrofuran with an alkyne tagged with fluorescent groups and another alkyne with an alpha,beta-unsaturated gamma-lactone. Assay for the growth inhibitory activity against human cancer cell lines revealed that the probe with the fluorescent groups at the end of the hydrocarbon chain may have the same mode of action as natural acetogenins. The merged fluorescence of dansyl-labeled solamin and MitoTracker Red suggests that Annonaceous acetogenins localize in the mitochondria. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.bmc.2010.10.004

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Language：English   Publisher：AMER CHEMICAL SOC  

The enantioselective total synthesis of (+)-hexachlorosulfolipid, a cytotoxin found in the Adriatic mussel Mytilus galloprovincialis, is described. The unique chlorinated hydrocarbon motif of the lipid is successfully furnished by a series of dichlorination reactions of chiral epoxides with chlorophosphonium reagent generated in situ from Ph(3)P/NCS. The present total synthesis has allowed the confirmation of the absolute configuration of the natural cytotoxic (+)-hexachlorosulfolipid originally proposed by Fattorusso, Ciminiello, and co-workers.

DOI： 10.1021/jo100534d

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Language：English   Publisher：GEORG THIEME VERLAG KG  

A route to the core structure of clavilactone D, a new member of the tyrosine kinase inhibitors, is reported. The route employs sequential cyclization initiated by iodo etherification followed by Friedel-Crafts cyclization to furnish a polycyclic lactone fused with an aromatic ring, which is readily transformed into the proposed clavilactone scaffold.

DOI： 10.1055/s-0029-1216909

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Language：English   Publisher：AMER CHEMICAL SOC  

The second-generation approach to (-)-agelastatin A has been established. The present strategy features the FeBr(2)-mediated radical cyclization of 2-cyclopentenyloxycarbonyl azide that allows for the stereoselective installation of a cis-vicinal aminobromo functionality suitable for producing the BCD-ring system of agelastatin A. The aminobromination method streamlines access to oxazolidinone, a key intermediate in the previously reported synthesis, thereby culminating in the new total synthesis of (-)-agelastatin A.

DOI： 10.1021/ol9012684

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Chaetomellic anhydride A, a potent inhibitor of Ras protein farnesyltransferase, was synthesized in 61% yield over four steps from methyl propionate. The synthesis features palladium-catalyzed carboxylation reaction under Cacchi conditions, efficiently incorporating carbon monoxide generated in situ from acetic formic anhydride into beta-carbomethoxyalkenyl triflate, and giving rise to the maleic anhydride motif of chaetomellic anhydride A. Noteworthy is the remarkable reactivity of the carboxylation reaction that takes place at room temperature despite the fact that common palladium-catalyzed carboxylations generally require rather harsh conditions. The scope of the method is also presented.

DOI： 10.3987/COM-08-S(F)16

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Language：English   Publisher：AMER CHEMICAL SOC  

Polychlorinated hydrocarbon motifs have been synthesized in enantiomerically pure forms by means of nucleophilic multiple chlorinations of chiral epoxides, which stereospecifically incorporate halogen atoms into oxygenated molecular scaffolds. The present study demonstrates the scope of the N-chlorosuccinimide (NCS)/organophosphine reagent system that forms multiple sp(3)C-Cl bonds in a regularly repeating pattern, with proper stereochemical configurations and evaluates its applicability to various epoxides having elaborate structures. It is noteworthy that tetrachlorinated motifs are produced in one step from bisepoxides by using NCS/Ph(3)P. Furthermore, Ph(2)PCl used in combination with NCS has been found to serve as a potentially useful alternative to NCS/Ph(3)P, especially for promoting dichlorination reactions of alkenyl-substituted epoxides.

DOI： 10.1021/jo802093d

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Language：English   Publisher：AMER CHEMICAL SOC  

A new route to (-)-agelastatin A is reported. The requisite nitrogen functionalities of the agelastatin core have been installed by intramolecular aziridination of an azidoformate and subsequent regioselective azidation, leading to net trans-diamination of the double bond. The present synthesis also demonstrates two new protocols for the preparation of an imidazolidinone hemiaminal motif from an oxazolidinone intermediate which comprise sequential N-tert-butoxycarbonylation, urea formation, hydrolysis, and oxidative cyclization, and direct aminolysis and subsequent oxidative cyclization.

DOI： 10.1021/ol802225g

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

An expeditious approach to (+/-)-aphanorphine has been established using readily available starting materials. The present synthesis relies on the direct assembly between N-methylpyrrolidone (NMP) and 2-bromoanisaldehyde, which takes place through Et(3)B/air-mediated transformation of the alpha-nitrogen-substituted sp(3)C-H bond, and features a new design concept for the synthesis of the tricyclic 3-benzazepine skeleton. (c) 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2008.05.058

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Language：Japanese  

CiNii Article

CiNii Books

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Language：English   Publisher：AMER CHEMICAL SOC  

A new carbamoylation of tertiary amines is reported. This rare C-H transformation features the direct generation of alpha-aminoalkyl radicals from tertiary amines, followed by the addition of the resultant nucleophilic radicals to isocyanates, enabling unique access to N,N-dlalkylated amino acid derivatives. The authors put forward a mechanistic proposal that is based on the isolation of borinamides produced by capturing nitrogen radical intermediates with Et3B. The present transformation provides a novel one-step process for producing mepivacaine, a clinically important local anesthetic, from readily available materials.

DOI： 10.1021/ol7023295

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Language：Japanese   Publisher：公益社団法人日本薬学会  

CiNii Article

CiNii Books

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Language：Japanese   Publisher：公益社団法人日本薬学会  

CiNii Article

CiNii Books

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Language：English   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/ja053855q

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Language：English   Publisher：AMER CHEMICAL SOC  

Ethers and an acetal were found to undergo direct intermolecular addition to aldehydes under the Et3B/air conditions. This study presents a very unique and simple means for the radical alpha-C-H hydroxyalkylation of oxygen-containing compounds.

DOI： 10.1021/jo048248k

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Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：AMER CHEMICAL SOC  

Alkoxyl radicals have a wide range of applications in organic synthesis due to their remarkable chemical properties in molecular transformation. The present study shows two types of alkoxyl radicals (primary vs tertiary) to selectively undergo dehydrogenation and beta-scission to give rise to key structural elements of (-)-CP-263,114 (1). By alkoxyl radical transformation followed by installation of the C19-C25 (CP numbering) side chain and the bridged bisacetal unit, the functionalized CP precursor 2 was obtained.

DOI： 10.1021/jo048681u

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Language：English   Publisher：AMER CHEMICAL SOC  

(+)-Muconin (1), isolated from the leaves of Rollinia mucosa (Jacq.) Baill. (Annonaceae), is a sequential THF/THP-possessing acetogenin that exhibits potent and selective in vitro cytotoxicity toward pancreatic and breast tumor cell lines. In this study, a new route was established for obtaining (+)-muconin (1) starting with (-)-muricatacin (2), a compound recently synthesized via the novel alpha-C-H hydroxyalkylation and alpha'-C-H oxidation of tetrahydrofuran.

DOI： 10.1021/jo0303721

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Language：English   Publisher：AMER CHEMICAL SOC  

(-)-Muricatacin, a potent cytotoxic (4R,5R)-5-hydroxyheptadecan-4-olide, has been synthesized through alpha-C-H hydroxyalkylation and alpha'-C-H oxidation of tetrahydrofaran. This study presents a novel method for C-H bond functionalization as a means for preparing gamma-(hydroxyalkyl)-gamma-butyrolactones.

DOI： 10.1021/jo0301696

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Language：English   Publisher：AMER CHEMICAL SOC  

The alpha-hydroxyalkylation of tetrahydrofuran with aldehydes via radical C-H abstraction was conducted using triethylborane in the presence of tert-butyl hydroperoxide. This study presents a rare instance of direct intermolecular radical addition of unactivated cyclic ether to aldehydes.

DOI： 10.1021/jo020590e

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Atom-transfer radical annulation of diene derived from D-glucose under Kharasch conditions provided access to the fully functionalized CD ring system of paclitaxel. (C) 2002 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(02)02058-0

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Language：English   Publisher：AMER CHEMICAL SOC  

[GRAPHICS]
The enantioselective construction of a fully functionalized core structure of (-)-CP-263,114 (1) containing most of the required functionality for total synthesis, was conducted through sequential radical fragmentation-reductive olefination.

DOI： 10.1021/ol000290o

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A new route to the synthesis of an optically active illudane skeleton from (R)-(-)-pantolactone (4) is established. The tricyclic ring system was constructed by Michael-Michael-elimination reaction of the enolate of (3S,5R)-3-(tert-butyldimethylsilyloxy)-5-methoxymethyloxy-1-propionylcyclopentene (10) with ethyl cyclopropylidenacetate (3). (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)00974-6

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Language：English   Publisher：ROYAL SOC CHEMISTRY  

The tetrahydrofuranyl radical, generated from THF with Et3B in the presence of air, was found to react with aldehydes threo-selectively to afford alpha-substituted tetrahydrofuran-2-methanols, the common structural motifs of biologically active acetogenin polyketides, in moderate yields.

DOI： 10.1039/A904745J

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Two complementary methods for the construction of the ring system of CP-263,114 (1), one relying on the Grob fragmentation reaction and the other on a sequential photolytic alkoxy radical fragmentation-reduction, are described. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)00941-7

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Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

A new synthetic route for construction of the core moiety of zaragozic acids from 2,5-furandimethanol (2) is described. This synthesis involves highly stereocontrolled transformation of 2 into 7-oxabicyclo[2.2.1] heptane derivative 13, and the Grob fragmentation-reduction-iodo acetalization reaction (one-pot process) of 13 as a key step to give 16. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)00256-7

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Language：English   Publishing type：Rapid communication, short report, research note, etc. (scientific journal)   Publisher：AMER CHEMICAL SOC  

DOI： 10.1021/jo971863m

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