Abstract

MICROWAVE-ASSISTED SYNTHESIS OF SOME PYRAZOLE DERIVATIVES VIA VILSMEIER-HAACK FORMYLATION AND THEIR BIOLOGICAL ACTIVITY

Deepak Swarnkar*, Rakshit Ameta, Ritu Vyas

ABSTRACT

3-Phenyl-(1-substituted phenyl/pyridine/thioamide)-1H-pyrazole-4-carbaldehydes (4a-e) were obtained by condensation of hydrazine hydrate, phenyl hydrazine, isoniazide, nicotinic hydrazide or thiosemicarbezide with acetophenone in ethanol containing a few drops of glacial acetic acid under microwave irradiation giving substituted(1-phenyl-ethylidine)hydrazine undergo Vilsmeier-Haack formylation. The products were condensed with various aromatic amines to give Schiff bases. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR and mass data. All the synthesized compounds have been screened for their antibacterial and antifungal activities.

Keywords: 3-Phenyl-(1-substituted phenyl/pyridine/thioamide)-1H-pyrazole-4-carbaldehyde, Antibacterial, Antifungal, Vilsmeier-Haack formylation, Microwave irradiation.