Design, synthesis, chemical characterization, biological evaluation, and docking study of new 1,3,4-oxadiazole homonucleoside analogs.

Herein, we report the synthetic strategies and characterization of some novel 1,3,4-oxadiazole homonucleoside analogs that are relevant to potential antitumor and cytotoxic activities. The structure of all compounds is confirmed using various spectroscopic methods such as H-NMR, C-NMR, HRMS, and FTIR. These compounds were evaluated against three human cancer cell lines (MCF-7, SKBR3, and HL60 Cell Line). Preliminary investigations showed that the cytotoxic activity was markedly dependent on the nucleobase. Introduction of 5-Iodouracil and theobromine proved to be extremely beneficial even they were more potent than the reference drug (DOX). Also, the synthesized compounds were tested for their antiviral activities against the human varicella-zoster virus (VZV). The product was (6-azauracil derivative) more potent to the reference (acyclovir) against the deficient TK - VZV strain by about 2-fold. Finally, molecular docking suggested that the anticancer activities of compounds and mediated by inhibiting dual proteins EGFR/HER2 with low micromolar inhibition constant Ki range. The 1,3,4-oxadiazole homonucleosides showed a strong affinity to binding sites of target proteins by forming H-bond, carbon-hydrogen bond, Pi-anion, Pi-sulfur, Pi-sigma, alkyl, and Pi-alkyl interactions.