著者

小島 孝一 雨宮 茂雄 末宗 洋 酒井 浄

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.33, no.7, pp.2750-2761, 1985-07-25 (Released:2008-03-31)

参考文献数

7

被引用文献数

3 4

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A general method for the stereospecific synthesis of 2, 3-trans-3, 4-cis-trisubstituted cyclopentanones (9) is described. This synthetic method has the advantage that three functional groups can be stereospecifically introduced on a five-membered ring by the catalytic hydrogenation of 2, 3, 4-trisubstituted cyclopentenones. Furthermore, 9 could be stereospecifically converted to 1, 2-trans-2, 3-trans-3, 4-cis-trisubstituted cyclopentanols (20) and 3, 4-cis-disubstituted cyclopentanones (11) by a simple procedure. These synthetic methods may be useful for the synthesis of natural products containing a five-membered ring.

著者

酒井 浄 石黒 靖尚 舟越 和久 上野 貢嗣 末宗 洋

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集 26 (ISSN:24331856)

巻号頁・発行日

pp.299-306, 1983-09-15 (Released:2017-08-18)

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Variously functionalized cyclopentanones are important as starting materials for the synthesis of natural products. We have succeeded in a simple, highly stereospecific synthesis of five membered ring ketone using Wilkinson complex. Thus, the precursors, 1-al-4-enes(4a-e,11,13) prepared in optically active form from D-limonene, (+)-limonen-10-ol and 1-carvone in three steps were submitted for RhCl(PPh_3)_3-catalyzed cyclization in CH_2Cl_2 to afford the cis-3,4-disubstituted cyclopentanones(14-22) in good yield (Table 2). The following results were obtained in this cyclization. 1) In all cases, the cis-3,4-disubstituted cyclopentanones were stereospecifically obtained as the sole products. 2) The cyclization reaction of the six membered lactols(12,13) was found to proceed very slowly even if at high temperature. 3) The cis-3,4-disubstituted cyclopentanones obtained in this method were also found to be applicable for the synthesis of bicyclic ketone(23). 4) The configurations of 3,4-disubstituents in each compounds were clarified by the way of chemical correlation and spectral analyses. Further application for the synthesis of ent-cis,cis-dihydro-nepetalactone(39) will be discussed.

著者

末宗 洋 上野 貢嗣 川原 哲也 小田 晃造 舟越 和久 酒井 浄

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集 27 (ISSN:24331856)

巻号頁・発行日

pp.108-114, 1985-09-07 (Released:2017-08-18)

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In the synthesis of natural products consisting of the basic structure of cyclopentane ring, variously functionalized cyclopentanones are required as starting materials. Previously, we succeeded in a simple, highly stereospecific synthesis of the cis-3,4-disubstituted cyclopentanones by the mild reaction with RhCl(PPh_3)_3. By the application of this newer cyclization reaction, we have succeeded in the synthesis of cis,cis-dihydronepetalactone, prostanoic acid, 8-isoprostanoic acid, (+)-brefeldin A and carbacyclin in the optically active form from limonene or Corey lactone. These compounds were synthesized via the following key steps. 1) 3-(3-Oxobutyl)cyclopentanone was easily converted to the deconjugated bicyclic enone (3→4). 2) The regioselective alkylation of limonene was performed by using s-BuLi-TMEDA (1→8). 3) The cis-3,4-disubstituted cyclopentanone from limonen-10-ol could be converted to the trans-3,4-disubstituted cyclo-pentanone by the epimerization (15→16, 22→23).

著者

末宗 洋 川原 哲也 酒井 浄

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.34, no.2, pp.550-557, 1986-02-25 (Released:2008-03-31)

参考文献数

13

被引用文献数

13 20

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Prostanoic acid (18) and 8-isoprostanoic acid (1) constitute the basic structures of primary prostaglandins and 8-isoprostaglandins. The conversion of commercially available (+)- and (-)-limonene to these compounds was accomplilshed by a sequence of reactions involving the Rh(I)-catalyzed cyclization of 3, 4-disubstituted 4-pentenals, which were easily prepared from (+)- or (-)-limonene, to cis-3, 4-disubstituted cyclopentanones and the appropriate modification of substituents on the five-membered ring.

著者

末宗 洋 小田 晃造 佐伯 清太郎 酒井 浄

出版者

公益社団法人日本薬学会

雑誌

Chemical & pharmaceutical bulletin (ISSN:00092363)

巻号頁・発行日

vol.36, no.1, pp.172-177, 1988-01-25

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This paper describes the conversions of (-)-limonene to four nepetalactones (1,2,ent-3 and 4) in a stereocontrolled manner. The cis-3,4-disubstituted cyclopentanone (5) obtained from (-)-limonene via Rh(I)-catalyzed cyclization of the 4-pentenal, could be converted to the bicyclo[3.3.0]octenone (6). After the stereoselective conversion of 6 into the diastereomeric isomers of the ketones (8 and 16), a sequence of reactions involving the silyl enol ethers (18 and 19), ozonolysis, and subsequent lactonization afforded the target molecules.

著者

末宗 洋 丸岡 博 佐伯 清太郎 酒井 浄

出版者

公益社団法人日本薬学会

雑誌

Chemical & pharmaceutical bulletin (ISSN:00092363)

巻号頁・発行日

vol.34, no.11, pp.4629-4634, 1986-11-25

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This paper describes a conversion of (-)-limonen-10-ol to the key intermediate (1) for 11-deoxyprostaglandin. The 3,4-cis-disubstituted cyclopentanone (2), which was easily obtained from (-)-limonen-10-ol in a stereocontrolled fashion by means of Rh(I)-catalyzed cyclization via the 4-pentenal derivative, could be directly converted to the bicyclo[3.3.0]octenone (3) by treatment with KHSO_4 in boiling benzene. Compound 3 with a double bond at the favorable position was converted to 1 by way of fission of the double bond and subsequent modification of substituents on the five-membered ring.

著者

末宗 洋 原部 哲治 謝 卓峰 酒井 浄

出版者

公益社団法人日本薬学会

雑誌

Chemical & pharmaceutical bulletin (ISSN:00092363)

巻号頁・発行日

vol.36, no.11, pp.4337-4344, 1988-11-25

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Asymmetric hydrolysis of 2,2-bis(acetoxymethyl)cyclopentanone (5) using biocatalysis and its application to a formal synthesis of (-)-melyngolide are described. For the asymmetric induction at the quanternary carbon of 5,cholinesterase from electric eel was found to be effective to afford the (+)-monoacetate (6) (90%ee). Compound (+)-6 was easily converted to the synthetic intermediate (28) for (-)-malyngolide.

著者

末宗 洋 原部 哲治 酒井 浄

出版者

公益社団法人日本薬学会

雑誌

Chemical & pharmaceutical bulletin (ISSN:00092363)

巻号頁・発行日

vol.36, no.9, pp.3632-3637, 1988-09-25

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Two trihydroxy unsaturated C-18 fatty acids [(9S, 12S, 13S)-trihydroxyoctadeca-10E, 15Z-dienoic acid (methyl ester) and (9S, 12S, 13S)-trihydroxy-10E-octadecenoic acid (methyl ester)] isolated from rice plants as agents with activity against blast disease were synthesized from (+)-dimethyl tartrate.

著者

末宗 洋 上野 貢嗣 川原 哲也 小田 晃造 舟越 和久 酒井 浄

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.27, pp.108-114, 1985

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In the synthesis of natural products consisting of the basic structure of cyclopentane ring, variously functionalized cyclopentanones are required as starting materials. Previously, we succeeded in a simple, highly stereospecific synthesis of the cis-3,4-disubstituted cyclopentanones by the mild reaction with RhCl(PPh_3)_3. By the application of this newer cyclization reaction, we have succeeded in the synthesis of cis,cis-dihydronepetalactone, prostanoic acid, 8-isoprostanoic acid, (+)-brefeldin A and carbacyclin in the optically active form from limonene or Corey lactone. These compounds were synthesized via the following key steps. 1) 3-(3-Oxobutyl)cyclopentanone was easily converted to the deconjugated bicyclic enone (3→4). 2) The regioselective alkylation of limonene was performed by using s-BuLi-TMEDA (1→8). 3) The cis-3,4-disubstituted cyclopentanone from limonen-10-ol could be converted to the trans-3,4-disubstituted cyclo-pentanone by the epimerization (15→16, 22→23).

著者

末宗 洋 川原 哲也 酒井 浄

出版者

公益社団法人日本薬学会

雑誌

Chemical & pharmaceutical bulletin (ISSN:00092363)

巻号頁・発行日

vol.34, no.2, pp.550-557, 1986-02-25

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Prostanoic acid (18) and 8-isoprostanoic acid (1) constitute the basic structures of primary prostaglandins and 8-isoprostaglandins. The conversion of commercially available (+)- and (-)-limonene to these compounds was accomplilshed by a sequence of reactions involving the Rh(I)-catalyzed cyclization of 3,4-disubstituted 4-pentenals, which were easily prepared from (+)- or (-)-limonene, to cis-3,4-disubstituted cyclopentanones and the appropriate modification of substituents on the five-membered ring.

著者

末宗 洋 田中 直樹 酒井 浄

出版者

The Pharmaceutical Society of Japan

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.38, no.11, pp.3155-3157, 1990-11-25 (Released:2008-03-31)

参考文献数

6

被引用文献数

6 6

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Diastereoselective acetalization of methyl pyruvate and methyl phenylformate with (R)-1, 3-butanediol afforded predominantly (2R, 4R)-2-methoxycarbonyl-2, 4-dimethyl (or 4-methyl-2-phenyl)-1, 3-dioxanes (1a, 4a) under thermodynamically controlled conditions. The (2S, 4R)-isomer (1b) was obtained as the major product under kinetically controlled conditions.

著者

酒井 浄 末宗 洋

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.46, no.4, pp.334-343, 1988-04-01 (Released:2009-11-13)

参考文献数

48

被引用文献数

1 1

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Starting with (+) - and (-) -limonenes as chiral synthons, syntheses of biologically active compounds such as prostaglandins, (+) -brefeldin A and nepetalactones have been studied. The key-step of these conversions is based on the stereoselective cyclization of 3, 4-disubstituted 4-pentenals into cis-3, 4-disubstituted cyclopentanones using the Rh (I) -complex.Ring cleavage and reconstruction of five and six membered rings under acetalization conditions are also discussed.

著者

末宗 洋

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.112, no.7, pp.432-446, 1992-07-25 (Released:2008-05-30)

参考文献数

42

被引用文献数

4 6

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The use of biocatalysts for the preparation of new chiral synthons has provided a novel synthetic route to the useful natural products. A method for the preparation of chiral carbocyclic alcohols has been also developed by utilizing the Pseudomonas fluorescens lipase (PFL)-catalyzed enantioselective hydrolysis. The above-mentioned alcohols have been found to be effective as chiral auxiliaries for asymmetric reactions.