Biocatalytic Preparation of Enantiopure p-Amino Acids

Biocatalytic Preparation of Enantiopure P-Amino Acids 14.2.2.1 Lipases and Aminoacyiases 

The catalytic conversion of N-chloroacetylated derivatives of p-amino acids using porcine kidney acylase type I showed significant activity, with the (S)-enantiomer of the acid being formed [35]. A 96% ee together with a 46% conversion was obtained when using a racemic p-methoxyphenyl-substituted substrate, whereas a 95% ee 

CAL-B lipase has been appHed to the resolution of some P-amino esters, by means of N-acylation or transesterification [27]. Resolution using CAL-B is complicated by the tendency of the en2yme to catalyze competing reactions at the amino and ester functional groups. However, CAL-B has proved very useful for resolution by means of P-lactam hydrolysis. 

Lipase PS has also demonstrated excellent biocatalytic potential for use in the O-acylation ofhydroxymethylated P-lactam compounds. Lipase PS, much like CAL-B, is capable of catalyzing N-acylation as well as reactions at the carboxylic group of the P-amino ester [27]. 

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