Pyrazine chemistry. Part VI. Addition of sulphur nucleophiles across dehydrocyclodipeptides

Abstract

A mild method for the addition of sulphur nucleophiles across the double bonds of dehydrocyclodipeptides is described. The method involves the direct addition of thiols to dehydrocyclodipeptides in the presence of an acid catalyst. Kinetic control affords the α-addition products and this process competes with a slower equilibration leading to the β-adducts. The route to the dehydrocyclodipeptides is detailed.