CROSS-LINKED CRYSTALS OF CANDIDA-RUGOSA LIPASE - HIGHLY EFFICIENT CATALYSTS FOR THE RESOLUTION OF CHIRAL ESTERS

To date, most enzyme-based organic syntheses have employed enzymes in the form. of a crude protein extract. The instability and expense of highly purified proteins has all but obviated their use as catalysts for enantioselective hydrolyses. Herein, we describe the use of the major hydrolase from commercial Candida rugosa lipase (CRL) in the form of a cross-linked enzyme crystal (CLEC) for the enantioselective hydrolysis of chiral racemic esters. The enantioselectivity of CRL-CLECs in the hydrolysis of many important chiral esters is vastly superior to that of the crude CRL extract. Since the CRL-CLEC is insoluble, recoverable, and 2-3 orders of magnitude more stable than the soluble protein, the CRL-CLEC is an attractive replacement for the crude enzyme preparation. The use of this catalyst in the resolution of chiral esters 1-11 and in the preparative scale (la):and multicycle resolution (2a) of important anti-inflammatory drugs is described.