Synthesis and Antimicrobial Activity of a New Class of Benzazolyl Pyrazoles

A new class of benzazolyl pyrazoles were prepared from the simple substrates benzoxazol-2-thiol, benzothiazol-2-thiol, 1H-benzimidazol-2-thiol and cinnamoyl chloride and tested for antimicrobial activity. The compounds 2-(benzothiazol-2-ylthio)-1-(3-(benzothiazol-2-ylthio)-5-phenyl-1H-pyrazol-1-yl)ethanone and 2-(benzothiazol-2-ylamino)-1-(3-(benzothiazol-2-ylthio)-5-phenyl-1H-pyrazol-1-yl)ethanone showed pronounced antibacterial activity against Klebsiella pneumoniae whereas 2-(1H-benzimidazol-2-ylthio)-1-(3-(1H-benzimidazol-2-ylthio)-5-phenyl-1H-pyrazol-1-yl)ethanone and 2-(1H-benzimidazol-2-ylamino)-1-(3-(1H-benzimidazol-2-ylthio)-5-phenyl-1H-pyrazol-1-yl) ethanone displayed excellent antifungal activity against Penicillium chrysogenum.