Synthesis and Biological Evaluation of Some Heterocycles from 1-Phenyl-3-(pyridine-3-yl)-1H-pyrazole-4-carbaldehyde

Abstract

Various substituted 2-hydroxy acetophenones (1) on condensation with 1-phenyl-3-(pyridin-3-yl)-1H-pyrazole-4-carbaldehyde (2) yields 1-(2-hydroxyphenyl)-3-(1-phenyl-3-(pyridine-3-yl)-1H-pyrazol-4-yl) prop-2-en-ones (3), which on treatment with DMSO/I2 give chromones (4) and treatment with hydrazine hydrates to give pyrazoline derivatives (6). Compound (4) react with hydrazine in ethanol to afford the pyrazole derivatives (5). The compounds were evaluated for their antimicrobial activities against Pseudomonas aeruginosa, Staphylococcus aureus and Candida sp. The antibacterial screening suggests that the analogs with electron releasing substituents emerged as promising antibacterial agents. The compounds synthesized were characterized by melting point, EIMS, NMR and FT-IR.