Background: Pyrimidines are an important component of nucleic acids and they have been used as
building blocks in pharmaceuticals for the synthesis of antiviral, antineoplastic, antibacterial, and antifungal
agents. Similarly, the related thiouracil derivatives are potential therapeutics as antiviral, anticancer, and antimicrobial
agents. For example, S-alkylation and N-alkylation products have been recently reported as novel antibacterial,
cytotoxic agents and unique HIV reverse transcriptase inhibitors.
Methods: The antiviral activity of HAV was determined through treatment of Vero cells with test materials 24 hr
pre-infection with an HAV model. HAV was 10-fold serially diluted in medium 199-E supplemented with 2%
FCS (GIBCO-USA). The end point dilution that induced 5% infectivity was determined. The antiviral activity of
the tested compounds was calculated by subtracting the infectivity titer of the cells treated with the virus test material
from that of the non-treated cells.
Results: Anticancer activity of the new compounds against MCF-7 and HEPG-2 showed compound 2 the most
potent active, followed by compound 6; their half maximal inhibitory concentrations(IC50) were 20.72, 25.46,
29.02 and 37.15, whereas compound 1 showed the lowest activity, with IC50 values of38.5 and 62.02. The antiviral
activity of the synthesized compounds revealed that all the tested compounds showed variable degrees of antiviral
activity with IC50 values ranging from 26.3 to 349.70. Results showed that compounds 1 and 3 had the highest
antiviral activity, with a high percentage of viral reduction.
Conclusion: The findings in results demonstrate the potential for thiouracils to serve as lead compounds for further
development as medicinal agents.