Reactions of Hydrazonoyl Halides 47: Synthesis of Some New 2,3-dihydro-1,3,4-thiadiazoles, Triazolo[4, 3-a]pyrimidines, and Pyrazolo[3, 4-d]pyridazines with Expected Biological Activity

2,3-dihydro-1,3,4-thiadiazoles, triazolino[4, 3-a]pyrimidines, andpyrazolo[3, 4-d]pyridazines were synthesized in good yields from reactions of hydrazonoyl halides with alkyl carbodithioates, pyrimidine-2-thione, and substituted prop-2-ene-1-one, respectively. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and an alternative synthesis method. Some of the new compounds were tested towards bacteria and fungi.