Fischer L, Wagner S A, Tacke R
Institut für Biochemie und Biotechnologie, Technische Universität Braunschweig, Germany.
Appl Microbiol Biotechnol. 1995 Jan;42(5):671-4. doi: 10.1007/BF00171942.
The prochiral sila-ketone acetyldimethyl(phenyl)silane (1) was reduced enantioselectively into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane [(R)-2] using resting cells of the commercially available yeast Saccharomyces cerevisiae (DHW S-3) as the biocatalyst. The bioconversion was performed on a 2.0-g scale in a 5-1 bioreactor. Starting with a substrate (1) concentration of 0.4 g.l-1, the highest production rate measured for this bioconversion was about 45-55 mumol (R)-2.l-1.min-1. After an incubation time of 1 h, all substrate in the medium had been converted, either biocatalytically reduced to (R)-2 or (probably chemically) converted into dimethyl(phenyl)silanol (Me2PhSiOH). After extraction of the cell-free medium with ethyl acetate/dichloromethane and subsequent purification of the extract by Kugelrohr distillation and chromatography on silica gel (medium-pressure liquid chromatography), 800 mg (yield 40%) of the bioconversion product (R)-2 was isolated. As shown by HPLC studies (cellulose triacetate as the chiral stationary phase) and 1H-nuclear magnetic resonance experiments (after derivatization of the bioconversion product with a chiral auxiliary agent), compound (R)-2 was almost enantiomerically pure (> 99% enantiomeric excess).
使用市售酵母酿酒酵母（DHW S-3）的静止细胞作为生物催化剂，将前手性硅酮乙酰基二甲基（苯基）硅烷（1）对映选择性还原为（R）-（1-羟乙基）二甲基（苯基）硅烷[（R）-2]。生物转化在5升生物反应器中以2.0克规模进行。从底物（1）浓度为0.4克/升开始，该生物转化测得的最高生产率约为45 - 55微摩尔（R）-2/升·分钟。孵育1小时后，培养基中的所有底物已被转化，要么通过生物催化还原为（R）-2，要么（可能通过化学方式）转化为二甲基（苯基）硅醇（Me2PhSiOH）。用乙酸乙酯/二氯甲烷萃取无细胞培养基，随后通过Kugelrohr蒸馏和硅胶柱色谱（中压液相色谱）对萃取物进行纯化，分离得到800毫克（产率40%）的生物转化产物（R）-2。如高效液相色谱研究（以三乙酸纤维素作为手性固定相）和1H核磁共振实验（在用手性助剂对生物转化产物进行衍生化后）所示，化合物（R）-2几乎是对映体纯的（对映体过量>99%）。
