Fluoro-2-Pyrimidinyl 1-Piperazinyl-1-Butanone

Antipsychotic drug enzymatic reduction of 1-(4-fluorophenyl) 4-[4-(5-fluoro-2-pyrimidinyl) 1 -piperazinyl]- -butanone. 

30 CHOLESTEROL-LOWERING AGENTS ENZYMATIC SYNTHESIS OF (3S,5/ )-DIHYDROXY-6-(BENZYLOXY) HEXANOIC ACID, ETHYL ESTER 

Cholesterol-lowering agents enzymatic synthesis of (3S,5/ )-dihydroxy-6-(benzyloxy)hexanoic acid, ethyl ester. 

A mixture of ethyl 3-keto-5-hydroxy 106 (major) and 5-keto-3-hydroxy 107 (minor) was obtained from partial microbial reduction of 104. These two mixtures were subjected to microbial reduction by Acinetobacter sp. SC 13874 cells for 6h. The results indicated that the second reduction of the monohydroxy compound by SC 13874 cells was quite enantioselective. Reduction of the 3-keto-5-hydroxy 106 provided predominantly the (3R)-hydroxy, while reduction of the 3-hydroxy-5-keto ester 107 provided predominantly the (5S)-hydroxy compmmd [134]. 

Three different KREDs were purified to homogeneity from cell extracts of A. calcoaceticus SC 13876, and their biochemical properties were compared. Reductase I only catalyzes the reduction of diketoester 105 to its monohydroxy products whereas reductase II catalyzes the formation of dihydroxy products from monohydroxy substrates. A third reductase (reductase III) was identified, which catalyzes the reduction of diketoester 105 directly to si/n-(3R,5S)-dihydroxy ester 103 [134]. Reductase III was cloned and expressed in E. coli and rec E. coli reduced the diketoester 105 to si/n-(3R,5S)-dihydroxy ester 103 with a 99.3% yield, 100% ee, and 99.8% de [116]. 

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