Sulfur/selenium-functionalized benzotriazoles as multifunctional antivirals targeting Zika & Chikungunya.

Aims: Emerging arboviruses such as Zika virus (ZIKV) and Chikungunya virus (CHIKV) remain significant public health threats. This study aimed to evaluate the antiviral potential of six organochalcogen compounds against ZIKV and CHIKV.

Materials & methods: Compounds were assessed for cytotoxicity and antiviral activity in Vero cells. Antiviral effects were determined using plaque reduction assays, time-of-addition studies, viral adsorption, and virucidal assays. Molecular docking and density functional theory (DFT) calculations were performed to investigate interactions with viral targets and electronic properties.

Results: Compounds 4, 7, 8, and 9 exhibited potent antiviral activity with low cytotoxicity, demonstrating effective inhibition of viral replication with half-maximal effective concentration (EC₅₀) values in the micromolar range and favorable selectivity indices. Mechanistic assays revealed that the compounds interfered with viral adsorption, exhibited virucidal effects, and inhibited multiple stages of the replication cycle. Docking studies confirmed strong binding to key viral enzymes, supported by HOMO (half-maximal effective concentration) - LUMO (lowest unoccupied molecular orbital) analysis.

Conclusions: These findings highlight organochalcogen compounds as promising dual-action antiviral candidates with broad-spectrum activity against ZIKV and CHIKV. Further preclinical investigations are warranted to explore their therapeutic potential.