Abstract
The stereoselective hydrolysis of the long-chain substrate p-nitrophenyl n-dodecanoyl-D (L) -phenylalaninate (D (L) -S12) in surfactant aggregates has been found to be easily controlled by changing amino acid sequence in peptide catalysts and composition of the aggregates. First, the LLL-tripeptide N- (benzyloxycarbonyl) -L-phenylalanyl-L-histidyl-L-leucine (Z-PheHisLeu) was most efficient for the enhancement of enantioselectivity among all the the peptide catalysts in this study. Second, remarkably high enantioselectivity of D (L) -S12 with Z-PheHisLeu was obtained in coaggregates composed of vesicular and micellar surfactants. It is emphasized on the basis of circular dichroism experiments that a favorable fitting of the L-isomer substrate and the active tripeptide like “key and lock” should be very important to enhance the enantioselectivity, and subsequently, the adjusting of the hydrophobic microenvironment to the optimum fit of reactants by changing appropriately the composition of coaggregates would induce the highest enantioselectivity.
