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An enzyme-catalyzed asymmetric hydrolysis of epoxides was achieved using an immobilized crude enzyme preparation derived from Rhodococcus sp. (NOVO SP 409). The mechanism of the reaction was shown to occur in a transspecific hydrolytic opening via an S N 2-type of reaction. Depending on the substitutional pattern of the substrate, optically active epoxides and 1,2-diols with varying optical purities were obtained (in one case e.e. 72%).

The most recent developments in the use of hydrolytic enzymes - proteases, lipases and nitrilases - are summarized: Sterically demanding a,a-disubstituted carboxylic esters can be enzymatically resolved using a commercially available protease derived from Aspergillus oryzae. A significant enhancement of selectivity and activity of Candida cylindracea lipase in irreversible acyl transfer reactions may be achieved by removal of by-products or via covalent modification of the enzyme. Enzymatic hydrolysis of nitriles proceeds under mild conditions but enzyme-catalysed side- reactions such as ester- or epoxide-hydrolysis may occur.

An enzyme-catalyzed asymmetric hydrolysis of epoxides was achieved using an immobilized crude enzyme preparation derived from Rhodococcus sp. (NOVO SP 409). The mechanism of the reaction was shown to occur in a transspecific hydrolytic opening via an S N 2-type of reaction. Depending on the substitutional pattern of the substrate, optically active epoxides and 1,2-diols with varying optical purities were obtained (in one case e.e. 72%).

The most recent developments in the use of hydrolytic enzymes - proteases, lipases and nitrilases - are summarized: Sterically demanding a,a-disubstituted carboxylic esters can be enzymatically resolved using a commercially available protease derived from Aspergillus oryzae. A significant enhancement of selectivity and activity of Candida cylindracea lipase in irreversible acyl transfer reactions may be achieved by removal of by-products or via covalent modification of the enzyme. Enzymatic hydrolysis of nitriles proceeds under mild conditions but enzyme-catalysed side- reactions such as ester- or epoxide-hydrolysis may occur.