Facile one-pot synthesis of 2-amino-1,3,4-oxadiazole tethered peptidomimetics by molecular-iodine-mediated cyclodeselenization

Synthesis of 2-amino-1,3,4-oxadiazole tethered peptidomimetics is described by reaction of N^α-protected amino acid hydrazides with isoselenocyanato esters in one pot. The molecular-iodine-mediated cyclodeselenization of in situ generated selenosemicarbazide intermediates resulted in facile formation of 2-amino-1,3,4-oxadiazoles under mild conditions at excellent yields. The method employs environmentally benign iodine as the cyclizing agent and thereby avoids the harsh conditions employed in existing routes.