PROTEASE-CATALYZED SYNTHESIS OF PRECURSOR DIPEPTIDES OF RGD WITH REVERSE MICELLES

The precursor dipeptides of RGD, Boc-Arg-Gly-OEt and Ac-Gly-Asp-diOMe, were synthesized in three reverse micellar systems using different pr oteases. The reaction conditions for the Boc-Arg-Gly-OEt synthesis cat alyzed by alcalase and for Ac-Gly-Asp-diOMe synthesis catalyzed by try psin in AOT/isooctane reverse micelles were optimized by examining the effects of several factors including water content, temperature, pH, reaction time, and the enzymes on the dipeptide yields. The best yield s for alcalase-catalyzed synthesis of Boc-Arg-Gly-OEt and trypsin-cata lyzed synthesis of Ac-Gly-Asp-diOMe were 62.7% and 78.8%, respectively . Two other reverse micelle systems, Triton/ethyl acetate and HTAB/hep tane/hexanol were also tested for the syntheses of the same dipeptides . (C) 1998 Elsevier Science Inc.