STEREOSELECTIVE EPOXIDATION OF PHE-GLY AND PHE-PHE VINYL ISOSTERES

Novel Phe-Gly and Phe-Phe isosteres have been synthesized. Vinylic iso steres of Phe-Gly and Phe-Phe were prepared by facile Julia reactions, and the resulting stereoisomers were isolated and epoxidized (m-chlor operbenzoic acid). Observed stereoselectivities of epoxidation appear to emanate from a cooperative coordination of the incoming peracid by the carbamate group and the more weakly coordinating allylic ester fun ction.