Synthesis and Structural Study of piperazine-2,5-diones derived from (R)-cysteine

Article abstract of DOI:10.1016/0957-4166(95)00168-O

Coupling Leuch's anhydrides obtained from (R)-thiazolidine-4-carboxylic acids 1 and 3 with one equivalent of the corresponding ethyl ester derivative of 1 or 3, leads to the formation of chiral piperazine-2,5-diones 2, 4, 5, 6, and 7, on thermal treatment of the intermediate dipeptides.The configuration of the products was established by nOe experiments.