著者
秋田 弘幸 古市 昭也 越地 弘子 堀越 弘毅 大石 武
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.32, no.4, pp.1342-1348, 1984-04-25 (Released:2008-03-31)
参考文献数
12
被引用文献数
6 8

The synthesis of optically active α-hydroxy β-methyl esters V by means of microbiological reduction of the corresponding α-keto β-methyl esters IV was carried out. Methyl 3-phenyl-2-oxobutyrate 3 was found to be reduced by a variety of yeasts to the α-hydroxy β-methyl esters (7b and 8a) with (2R, 3S)-and (2R, 3R)-configurations, respectively, and by carrying out screening experiments, yeasts which give products with high optical purity were actually found.
著者
秋田 弘幸 古市 昭也 越地 弘子 堀越 弘毅 大石 武
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.32, no.4, pp.1333-1341, 1984-04-25 (Released:2008-03-31)
参考文献数
13
被引用文献数
14 17

Microbiological asymmetric reduction of methyl 3-(2-furyl)-2-methyl-3-oxopropionate (5) by various yeasts was carried out. Four kinds of methyl 3-(2-furyl)-3-hydroxy-2-methyl propionates (6a-6d) could be obtained separately from the prochiral β-keto ester 5 by reduction with properly selected microorganisms. In particular, the desired syn-isomer 6a was obtained with high optical purity (>99% e.e.). Both the chemical yield and the optical purity of the reduction products (6a-6d) were significantly improved when fermentation was carried out on a large scale using a 30 1 jar fermentor or a 200 1 tank.
著者
秋田 弘幸 古市 昭也 越地 弘子 堀越 弘毅 大石 武
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.31, no.12, pp.4384-4390, 1983-12-25 (Released:2008-03-31)
参考文献数
13
被引用文献数
10 13

In order to synthesize four optically active methyl 2-methylmalates (10-13), microbiological asymmetric reduction of the corresponding dimethyl 2-methyl-3-oxosuccinate (9) was carried out. The β-keto diester 9 was found to be reduced by fermenting baker's yeast (Saccharomyces cerevisiae) and Candida albicans to afford a mixture of the (2R, 3R)-isomer 10 and the (2S, 3R)-isomer 11. Although the optical purity of 10 produced by Candida albicans was reasonably high (95% e.e.), optical yields of other products were unexpectedly low. However, identification of the four possible isomers 14-17 was found to be easily carried out by means of nuclear magnetic resonance spectroscopy.
著者
秋田 弘幸 古市 昭也 越地 弘子 堀越 弘毅 大石 武
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.31, no.12, pp.4376-4383, 1983-12-25 (Released:2008-03-31)
参考文献数
19
被引用文献数
18 30

The synthesis of optically active α-methyl β-hydroxy esters I by means of microbiological reduction of the corresponding β-keto esters II was carried out. Benzyl 2-methyl-3-oxobutyrate 1 was found to be reduced by a variety of yeasts to the α-methyl β-hydroxy esters with (2R, 3S)- and (2S, 3S)-configurations (2 and 3, respectively), and by carrying out screening experiments, yeasts which give each product with high optical purity were isolated. Moreover, the absolute configuration and the optical purity of the reduction products were found to be determinable from the 400 MHz nuclear magnetic resonance spectra of the (+)-α-methyoxy-α-trifluoromethylphenylacetyl esters of the alcohols produced.