Abstract:
Novel N-(Cbz-aminoacyl)thiosemicarbazides 3a−c were cyclized by treatment with sulfuric acid to give 1,3,4-thiadiazoles 4a−c. Compounds 4a−c reacted with N-(Cbz-aminoacyl)- and -dipeptidoylbenzotriazoles to afford chirally pure 1,3,4-thiadiazol-2-yl-substituted amino acids 6a−c and dipeptides 7a−c.