[Some derivatives of the 2-[4-pyrazolinyl]-1,3,4-thiadiazole system].

The synthesis of some 2-[5-amino-1-methyl-3-oxo-4-pyrazolynyl]-1,3,4-thiadiazole derivatives is accomplished by reacting 5-amino-1-methyl-3-oxopryrazolynyl-4-dithiocarbohydrazide with carboxylic acid derivatives. The structure of the compounds obtained is verified by means of 1H and 13C-N.M.R. spectra. Antimicrobial and antifungal activity of some of the described compounds was tested in a preliminary screening.