A series of novel 2-[(substitutedphenyl/heteroaryl)imino]-3-phenyl-1,3-thiazolidin-4-ones (4a-g) were synthesized and structurally confirmed by elemental, IR, 1H NMR and MS spectral analysis. Further, the antiviral screening of 2-[(substitutedphenyl/heteroaryl)imino]-3-phenyl-1,3-thiazolidin-4-ones (4a-g) against a broad panel of DNA and RNA viral strains indicated that (2Z)-3-phenyl-2-(1,3-thiazol-2-ylimino)-1,3-thiazolidin-4-one (4c), (2Z)-2-[(2,6- dimethylphenyl)imino]-3-phenyl-1,3-thiazolidin-4-one (4g), (2Z)-2-[(3,4-dimethylphenyl)imino]-3-phenyl-1,3- thiazolidin-4-one (4a) and (2E)-3-phenyl-2-(pyridin-3-ylimino)-1,3-thiazolidin-4-one (4d) showed promising antiviral activity against vesicular stomatitis virus (EC50 = 4, 8, 9 and 11 μM, respectively) tested in HeLa cell culture, (2Z)-2-[(3,4-dimethylphenyl)imino]-3-phenyl-1,3-thiazolidin-4-one (4a) emerged as the best antiviral agent against cytomegalovirus [EC50 = 49 μM (AD-169 and Davis)], (2E)-3-phenyl-2-(pyridin-3-ylimino)-1,3-thiazolidin- 4-one (4d) and (2E)-2-[(3,5-dimethylphenyl)imino]-3-phenyl-1,3-thiazolidin-4-one (4f) against varicella-zoster virus (VZV) [thymidine kinase positive (TK+) VZV (OKA strain)] (EC50 = 39 and 39 μM, respectively). (2Z)-3- phenyl-2-(1,3-thiazol-2-ylimino)-1,3-thiazolidin-4-one (4c) was active against varicella-zoster virus (VZV) [thymidine kinase deficient (TK-) VZV (07/1 strain)] (EC50 = 37 μM) tested in human embryonic lung (HEL) cell cultures. They may be considered as potential lead compounds for the development of novel antiviral agents.
