Biological Activity Evaluation of Some New Benzenesulphonamide Derivatives

Abstract

Bacterial resistance to antibiotics has become one of the most challenging problems of infectious disease treatment. Ten new derivatives of benzenesulphonamide bearing carboxamide functionality were synthesized and investigated for their <i>in vivo</i> anti-inflammatory, <i>in vitro</i> anti-microbial and anti-oxidant activities. The base promoted reactions of the appropriate amino acids with substituted benzenesulphonyl chlorides gave the benzene sulphonamides (<b>3a-j</b>) in excellent yields. Palladium mediated amidation of the benzenesulphonamides (<b>3a-j</b>) and butylamine gave the new carboxamides (<b>4a-j</b>) in excellent yield. Compounds <b>4a</b> and <b>4c</b> inhibited carrageenan induced rat-paw edema at 94.69, 89.66, and 87.83% each at 1, 2, and 3 h, respectively. In the antimicrobial activity, compound <b>4d</b> (MIC 6.72 mg/mL) was most potent against <i>E. coli</i>, compound <b>4h</b> (MIC 6.63 mg/mL) was the most active against <i>S. aureus</i>, compound <b>4a</b> (MIC 6.67 and 6.45 mg/mL) was most active against <i>P. aeruginosa</i> and <i>S. typhi</i>, respectively, compound <b>4f</b> (MIC 6.63 mg/mL) was the most active against <i>B. subtilis</i>, compounds <b>4e</b> and <b>4h</b> (MIC 6.63 mg/mL) each were the most active against <i>C. albicans</i>, while compound <b>4e</b> (MIC 6.28 mg/mL) was most active against <i>A. niger</i>. Only compound <b>4e</b> (IC₅₀ 0.3287 mg/mL) had comparable activity with Vitamin C (IC₅₀ 0.2090 mg/mL).