Antimicrobial and in vitro cytotoxicity of novel sulphanilamide condensed 1,2,3,4-tetrahydropyrimidines

The purpose of the study was to synthesize potent antimicrobial and cytotoxic agents by condensing sulphanilamide with 1,2,3,4-tetrahydropyrimidines. A new series of novel sulphanilamide condensed 1,2,3,4-tetrahydropyrimidines was prepared by reacting N-[(4-aminophenyl) sulphonyl]-3-oxobutanamide with urea/thiourea and aryl aldehyde in the presence of a catalytic amount of laboratory prepared chlorosulphonic acid as an efficient catalyst. The chemical structures of the synthesized compounds (7a-r) were confirmed by TLC, and the compounds were characterized by IR, 1H NMR, mass spectra and elemental analysis. The synthesized compounds were evaluated for antimicrobial activity against the Gram-positive bacteria Bacillus subtilis and the Gram-negative bacteria Escherichia coli and for cytotoxicity against Vero cells. These compounds exhibited weak, moderate, or high antimicrobial activities and cytotoxicity. In particular, compound 7p exhibited the best antimicrobial activity and cytotoxicity of all the 1,2,3,4-tetrahydropyrimidine derivatives with antimicrobial activity MIC values of 11.4μM and 12.1μM against B. subtilis and E. coli, respectively, and a cytotoxicity CTC50 value of 19.0μM against Vero cells. The sulphanilamide condensed 1,2,3,4-tetrahydropyrimidines generated here might prove interesting as potential antimicrobial cytotoxic agents.