研究者詳細 - 清田　洋正

論文 - 清田　洋正

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Synthesis and antitumor activity of 2-(m-substituted-benzoyl)baccatin III analogs from taxinine

T Horiguchi, T Oritani, H Kiyota

TETRAHEDRON 59 ( 9 ) 1529 - 1538 2003年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

6 Didemniserinolipid Bの全合成と構造の改定(口頭発表の部)

清田洋正, Dixon Darren J., Luscombe Christine K., Hettstedt Stephen, Ley Steven. V.

天然有機化合物討論会講演要旨集 ( 44 ) 31 - 36 2002年9月

記述言語：日本語出版者・発行元：天然有機化合物討論会

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

Synthesis, structure revision, and absolute configuration of (+)-didemniserinolipid B, a serinol marine natural product from a tunicate Didemnum sp.

H Kiyota, DJ Dixon, CK Luscombe, S Hettstedt, SV Ley

ORGANIC LETTERS 4 ( 19 ) 3223 - 3226 2002年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Syntheses and odour descriptions of cyclopropanated compounds 2. Analogues of methyl jasmonate

H Kiyota, T Koike, E Higashi, T Oritani

FLAVOUR AND FRAGRANCE JOURNAL 17 ( 4 ) 267 - 271 2002年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

A new drimane from the heartwood of the Japanese yew, Taxus cuspidata

H Kiyota, QW Shi, T Oritani

NATURAL PRODUCT LETTERS 16 ( 1 ) 21 - 24 2002年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Syntheses and odour descriptions of cyclopropanated compounds 3.1 Analogues of leaf alcohol, its esters and leaf acetal 査読

Hiromasa Kiyota, Emi Higashi, Takafumi Takai, Takayuki Oritani, Shigefumi Kuwahara

Flavour and Fragrance Journal 17 ( 3 ) 227 - 231 2002年

記述言語：英語掲載種別：研究論文（学術雑誌）

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

Synthesis of southern (C1 '-C11 ') and eastern (C8-C18) fragments of pamamycin-607, an aerial mycelium-inducing substance of Streptomyces alboniger

H Kiyota, Y Furuya, S Kuwahara, T Oritani

BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 65 ( 12 ) 2630 - 2637 2001年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Stereochemistry of enacyloxins. Part 3. (12 ' S,17 ' R,18 ' S,19 ' R)-absolute configuration of enacyloxins, a series of antibiotics from Frateuria sp W-315

R Takeuchi, H Kiyota, M Yaosaka, T Watanabe, K Enari, T Sugiyama, T Oritani

JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1 2001 ( 20 ) 2676 - 2681 2001年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

88(P-45) Pamamycin-607の合成研究(ポスター発表の部)

古屋幸人, 清田洋正, 桑原重文

天然有機化合物討論会講演要旨集 ( 43 ) 521 - 526 2001年9月

記述言語：日本語出版者・発行元：天然有機化合物討論会

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

Synthesis of macrotetrolide alpha, a designed polynactin analog composed of (+)- and (-)-bishomononactic acids

T Hanadate, H Kiyota, T Oritani

BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 65 ( 9 ) 2118 - 2120 2001年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Synthesis of (-)-methyl shikimate via enzymatic resolution of (1S*, 4R*, 5R*)-4-hydroxy-6-oxabicyclo[3.2.1]oct-2-en-7-one

T Oritani, R Ueda, H Kiyota

BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY 65 ( 9 ) 2106 - 2109 2001年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Syntheses and odour descriptions of jasmine lactone and cis-jasmone analogues bearing cyclopropane moieties

H Kiyota, E Higashi, T Koike, T Oritani

FLAVOUR AND FRAGRANCE JOURNAL 16 ( 3 ) 175 - 179 2001年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

Lipase-catalyzed preparation of both enantiomers of methyl jasmonate

H Kiyota, E Higashi, T Koike, T Oritani

TETRAHEDRON-ASYMMETRY 12 ( 7 ) 1035 - 1038 2001年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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

New 11(15->10)Abeotaxane, 11(15->1),11(10->9)Bisabeotaxane and 3,11-Cyclotaxanes from Taxus yunnanensis

Hiromasa Kiyota,* Qing-Wen Shi, Takayuki Oritani, Ligeng Li

Bioscience, Biotechnology, and Biochemistry 65 ( 1 ) 35 - 40 2001年1月

Synthesis of Actiketal, an Unique Benzofuran Glutarimide Antibiotic from Streptomyces pulveraceus subsp. epiderstagenes

Hiromasa Kiyota,* Yuko Shimizu, Takayuki Oritani

Journal of Pesticide Science 26 ( 1 ) 93 - 95 2001年

(±)-Methyl 11-Fluorojasmonate as a Designed Antimetabolite of Methyl Jasmonate: Synthesis and Plant Growth Regulatory Activity

Hiromasa Kiyota, Takanori Koike, Emi Higashi, Yasushi Satoh, Takayuki Oritani

Journal of Pesticide Science 26 ( 1 ) 96 - 99 2001年

Stereochemistry of enacyloxins 1. Absolute configuration of the cyclohexane ring part of enacyloxins, a series of antibiotics from Frateuria sp W-315

T Fujimori, O Nakayama, H Kiyota, Y Kamijima, T Watanabe, T Oritani

HETEROCYCLIC COMMUNICATIONS 7 ( 4 ) 327 - 330 2001年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：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.

Stereochemistry of enacyloxins 2. Structure elucidation of decarbamoyl enacyloxin IIa and IVa, new members of enacyloxin antibiotics from Frateuria sp W-315

T Watanabe, H Kiyota, R Takeuchi, K Enari, T Oritani

HETEROCYCLIC COMMUNICATIONS 7 ( 4 ) 313 - 316 2001年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：FREUND PUBLISHING HOUSE LTD

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.

Synthesis of (-)-ent-Altholactone, (＋)-7a-epi-Altholactone, (-)-ent-Isoaltholactone and (-)-7a-epi-Isoaltholactone from 2,3-O-Cyclohexylidene-D-glyceraldehyde

Akira Hiratate, Hiromasa Kiyota, Takayuki Oritani

Journal of Pesticide Science 26 ( 4 ) 361 - 365 2001年

Synthesis of both enantiomers of altholactone, isoaltholactone and 5-hydroxygoniothalamin from tri-O-acetyl-D-glucal, and their biological activities

A Hiratate, H Kiyota, T Noshita, R Takeuchi, T Oritani

JOURNAL OF PESTICIDE SCIENCE 26 ( 4 ) 366 - 370 2001年

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PESTICIDE SCI SOC JAPAN

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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