Abstract Reactions of 3-oxo-N-phenylbutanethioamide with 3-substituted 5-amino-1 H-1, 2, 4-triazoles in acetic acid led to the formation of 5-methyl-7, 8-dihydro [1, 2, 4] triazolo [1, 5-a] pyrimidine-7-thiones, 7-methyl-5, 8-dihydrol [1, 2, 4] triazolo [1, 5-a] pyrimidine-5-thiones and 7-methyl-5-phenylamino [1, 2, 4] triazolo [1, 5-a] pyrimidines. The structure of the products was proved by the 1 H and 13 C NMR spectra, X-ray diffraction data, and ...