A systematic study of the reactions of dimethyl acetylenedicarboxylate (DMAD) with heterocyclic thioamides has been carried out and a number of new 2-isoxazolyl-(8), imidazolyl-(13a, b and 17a), 1, 2, 3-triazolyl-(13d, e) and 1, 2, 3-thiadiazolyl (17b) thiazolines have been prepared. The higher reactivity of the thioamide group in comparison with the amino group in these reactions has been established.
