Synthesis and Biological Evaluation of Sulfonamide Derivatives as Antimicrobial Agents.

The present study investigates, the synthesis of new derivatives of benzenesulfonamide nucleus hybridized with various substituted pyrazole 4, 8 and thiazole ring 6 using 4-amino-N-butylbenzenesulfonamide 1 as the key starting compound. Furthermore, 3,5-diaminopyrazole derivative 10 was allowed to react with different reagents such as an active methylene compounds, ketone dithioacetal, ethoxymethylene malononitrile and cyanoguanidine for a preparation of new benzenesulfonamide derivatives 11-18 conjugated with different substituted hetero-bicyclic ring systems. In vitm-antimicrobial evaluation was performed for most of the newly synthesized compounds using ciprofloxacin and Fluconazole as antibacterial and antifungal standard drugs, respectively The most promising dual antibacterial and antifungal potency was gained by the sulfamoylphenyl butenoic acid derivative 7, followed by the sulfamoylphenyl-2-chloroacetamide 5 and its heterocyclic pyrazolopyrimidine derivative 16. Further development and structural optimization will be carried out to get new more potent and safer antimicrobials.