Synthesis and antimicrobial evaluation of some 4-quinolinylazo-N-pyrimidinyl benzenesulfonamide derivatives

Ten new compounds of quinoline clubbed with sulfonamide moiety were synthesized to be used as antimicrobial agents. Therefore, the diazotized N-(pyrimidin-2-yl)-benzenesulfonamide was diazocoupled with 8-hydroxyquinoline to furnish 4-(8-hydroxyquinolin-5-yl)-N-(pyrimidin-2-yl)benzenesulfonamide (3) which underwent chloroacetylation by chloroacetyl chloride to give the corresponding O-chloroacetylated product 6. The reactions of quinolinyl 2-chloroacetate derivative 6 with different nucleophiles (ethyl 2-mercaptoacetate, 2-mercapto-4,6-dimethylnicotinonitrile, o-aminothiophenol and/or malononitrile) were studied and utilized to pick up various heterocyclic systems 7, 10, 12 and 14. The chemical structures of newly prepared quinoline-containing scaffolds have been confirmed based on their spectral data (IR, 1H NMR and MS) and have been tested for their antimicrobial activity. The results showed that compounds 5d, 6, 7 and 14 displayed the highest activity against Gram-positive bacteria.