Utility of 2-(5-methyl-1-phenyl-1<i>H</i>-pyrazol-4-yl)-2-oxo-<i>N</i>′-phenylaceto-hydrazonoyl bromide as precursor for synthesis of new functionalized heterocycles

<p>2-(5-Methyl-1-phenyl-1<i>H</i>-pyrazol-4-yl)-2-oxo-<i>N</i>′-phenylaceto-hydrazonoyl bromide was synthesized and used as precursor for synthesis of some new 1,3,4-thiadiazoles, pyrrolo[3,4-<i>c</i>]pyrazoles, and 1,2,4-triazolo[4,3-<i>a</i>]pyrimidines. The mechanisms that account for formation of products were discussed. Also, the structures of all the newly synthesized products were confirmed based on elemental analysis, spectral data and by alternative methods.