Abstract

Uracil derivatives, as key components of nucleic acids, are vital targets for therapeutic intervention, particularly in oncology and virology. This study focuses on the **synthesis and characterization** of a novel series of uracil derivatives, designed to exhibit enhanced **antiviral and anticancer potential**. The primary objective was to develop compounds that could interfere with cellular processes critical for viral replication and uncontrolled cell proliferation, such as DNA/RNA synthesis or membrane transport mechanisms. Using a multi-step organic synthesis approach, several new compounds were successfully created and their structures confirmed by spectroscopic methods. Subsequent biological evaluation involved *in vitro* assays, including cytotoxicity screening against a panel of human cancer cell lines (e.g., HeLa, MCF-7) and antiviral activity against representative RNA and DNA viruses. Key findings indicate that several synthesized derivatives exhibit potent and selective cytotoxic effects, with IC50 values in the low micromolar range, suggesting a potential mechanism involving mitochondrial membrane disruption or apoptosis induction. Furthermore, certain compounds demonstrated significant antiviral efficacy, likely by inhibiting viral polymerase or interfering with host cell membrane fusion. These results highlight the therapeutic promise of these new uracil derivatives and warrant further investigation into their precise molecular targets and *in vivo* efficacy.