. INTRODUCTIONDespite significant advances in antiviral drug development during the past two decades, viral infections continue to cause serious morbidity and mortality world-wide. Diverse antiviral drugs are now available for the treatment of infections by HIV, herpes-, influenza, hepatitis B or hepatitis C viruses. Except for the broad antiviral agent ribavirin, there is no approved therapy for diverse emerging RNA viruses. In addition, new antiviral molecules are required to tackle the problems of drug toxicity and rapid development of drug resistance, which is particularly problematic for mutation-prone RNA viruses. Since virus replication occurs within host cells, and host cell metabolism and viral replication are tightly integrated, the development of compounds which selectively interfere with virus-specific process is one of the main challenges in antiviral drug design.Imidazo [21][22][23][24][25][26][27][28][29][30][31][32] (including antiviral molecules) (either as a substituent group or as a replacement for another cyclic system). For instance, several 2,3-diaryl-1,3-thiazolidin-4-ones have proved to be potent nonnucleoside HIV reverse transcriptase inhibitors (NNRTIs) [33,34]. The HIV RT is a prime target for designing HIV inhibitors [35,36].We here report the synthesis, structural determination and antiviral evaluation of . 3-alkyl/aryl-2-[((6-(phenyl/4-chlorophenyl)imidazo[2,1-b]thiazol-3-yl)acetyl)hydrazono]-5-nonsubstituted/methyl-4-thiazolidinones.

Six novel cyclohexylidenehydrazide derivatives carrying five membered heterocyclic ring, 1,3-thiazole were synthesized to investigate their antiviral (including anti-HIV) activity against diverse DNA and RNA viruses in CRFK, HeLa, HEL, MDCK, Vero and MT4 cell cultures. None of the compounds was found active against any of the DNA or RNA viruses at 100 μM.