New series of 2-thioxo imidazolidin-4-one derivatives were synthesized. The newly synthesized compounds were screened for antimicrobial activity and compared with Ciprofloxacin and Clotrimazole standards. 2- Thioxoimidazolidin-4-ones (3a-f) and (4a-f) were synthesized employing Mannich base method by interacting 2- thioxoimidazolidin-4-one (2) with benzaldehyde and thiosemicarbazide or semicarbazide . The structures of the synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and mass spectral studies. The synthesized compounds were screened for in vitro antibacterial activity against various bacterial strains and antifungal activity against various fungal strains. Compound (3b) was highly active against S.aureus compared with standard Ciprofloxacin in antibacterial screening, and compound (4d) was highly active against A.niger compared with Clotrimazole in antifungal screening.
