Lipases and whole cell biotransformations of 2-hydroxy-2-(ethoxyphenylphosphinyl)acetic acid and its ester

Abstract

A wide spectrum of commercially available lipases and microbial whole cells catalysts were tested for biotransformations of 2-hydroxy-2-(ethoxyphenylphosphinyl)acetic acid 1 and its butyryl ester. The best results were achieved for biocatalytic hydrolysis of ester: 2-butyryloxy-2-(ethoxyphenylphosphinyl)acetic acid 2 performed by lipase from Candida cylindracea, what gave optically active products with 85% enantiomeric excess, 50% conversion degree and enantioselectivity 32.9 for one pair of enantiomers. Also enzymatic systems of Penicillium minioluteum and Fusarium oxysporum were able to hydrolyze tested compound with high enantiomeric excess (68–93% ee), enantioselectivity (44 for one pair of enantiomers) and conversion degree about 50–55%. Enzymatic acylation of hydroxyphosphinate was successful in case when porcine pancreas lipase was used. After 4days of biotransformation the conversion reaches 45% but the enantiomeric enrichment of the isomers mixture do not exceed 43%. Obtained chiral compounds are valuable derivatizing agents for spectroscopic (NMR) evaluation of enantiomeric excess for particular compounds (e.g. amino acids).