Enzymes In Organic Synthesis

Abstract

This article describes applications of enzymes as catalysts in organic synthesis. It outlines the general mechanistic principles that govern enzyme‐catalyzed asymmetric synthesis and enantioselective resolutions and offers a special emphasis to the widely practiced hydrolytic reaction for the synthesis of monoesters of dicarboxylic acids and monoacylated diols. The use of hydrolytic enzymes for acylations in nonaqueous media is illustrated by the synthesis of chiral lactones and polyesters and regioselective acylations of polyhydroxy compounds. Utilization of hydrolases is also extended to resolution of racemic amines and amino acids, and enzymatic hydrolysis of nitriles. Thermodynamic and kinetic aspects of enzymatic peptide synthesis are analyzed and the most recent trends in enzyme‐catalyzed peptide condensations are illustrated by a number of examples. The synthetic utility of lyases is demonstrated by a number of aldolase‐ and ketolase‐catalyzed condensations of carbon‐carbon bonds and by the synthesis of cyanohydrins by oxynitrilases. Oxidoreductases are represented by dehydrogenases commonly used for the synthesis of chiral alcohols, lactones, hydroxy, and amino acids; by cyclohexanone monooxygenase, the enzyme that catalyzes Baeyer‐Villiger oxidation of ketones; and by lipoxygenase, which incorporates dioxygen into polyunsaturated fatty acids.