Chemotherapeutic Agents, XV. Synthesis of 4‐Amino‐3‐pyrazolo‐1,2,4‐triazoles as Antimicrobial Agents

4-Amino-3-hydrazino-5-H/methyl-1,2,4-triazole dihydrochlorides (2a,b) were obtained by cyclization of triamino-guanidine-HCl in formic and acetic acids, respectively. Condensation of 2a with pyrazol-4-carbaldehydes in ethanol yielded 3a,b. Cyclocondensation of 2a,b with dimethylmercaptocyanoacrylonitrile, methyl dimethylmercapto-cyanoacrylate, ethoxymethylenemalononitrile and ethyl ethoxymethylenecyanoacetate individually provided 4a-d and 5a-d, respectively. The hydrazones 6a,b were obtained by refluxing 4-amino-3-(5-amino-4-ethoxycarbonyl pyrazol-1-yl)-1,2,4-triazole (5b) with aryl aldehydes in ethanol. Interaction of 2a with acetylacetone and 2-ethoxycarbonylcyclopentanone separately yielded 7 and 8 while reaction with 2-ethoxycarbonylcyclohexanone provided the bicyclic compounds 9a,b. Some of the compounds were screened for antibacterial and antifungal activities but none of them showed any significant activity.