Novel pyrazole derivatives as potential promising anti-inflammatory antimicrobial agents

Four series of 1H-pyrazole derivatives have been synthesized. The first series was synthesized starting by condensing the hydrazine derivatives 1a-d with 4-(1-ethoxycarbonyl-2-oxopropyl)azobenzoic acid 2a in ethanol or glacial acetic acid to generate the corresponding pyrazoline derivatives 3a-d. Likewise, heating 1a-d with 4-(1-acetyl-2-oxopropyl)azobenzoic acid 2b gave rise to the pyrazole derivatives 4a-d. Similarly, reaction of 1a-d with ethyl 2-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-ylazo)-3-oxobutanoate 2c or 3-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl azo)pentane-2,4-dione 2d in ethanol or glacial acetic acid led to the corresponding pyrazoline derivatives 5a-d or pyrazole derivatives 6a-d. The newly synthesized compounds were evaluated for their anti-inflammatory-antimicrobial activities. In addition, the ulcerogenic and acute toxicity profiles were determined. Compound 6c, proved to be the most active anti-inflammatory-antimicrobial agent in the present study with a good safety margin and no ulcerogenic effect.