Design and statistical optimisation of emulsomal nanoparticles for improved anti-SARS-CoV-2 activity of N-(5-nitrothiazol-2-yl)-carboxamido candidates: in vitro and in silico studies

In this article, emulsomes (EMLs) were fabricated to encapsulate the N-(5-nitrothiazol-2-yl)-carboxamido derivatives (3a–3g) in an attempt to improve their biological availability and antiviral activity. Next, both cytotoxicity and anti-SARS-CoV-2 activities of the examined compounds loaded EMLs (F3a–g) were assessed in Vero E6 cells via MTT assay to calculate the CC(50) and inhibitory concentration 50 (IC(50)) values. The most potent 3e-loaded EMLs (F3e) elicited a selectivity index of 18 with an IC(50) value of 0.73 μg/mL. Moreover, F3e HIGHLIGHTS: Emulsomes (EMLs) were fabricated to encapsulate the N-(5-nitrothiazol-2-yl)-carboxamido derivatives (3a–3g). The most potent 3e-loaded EMLs (F3e) showed an IC(50) value of 0.73 μg/mL against SARS-CoV-2. F3e exhibited a combination of virucidal (>90%), viral adsorption (>80%), and viral replication (>60%) inhibition. Molecular docking, molecular dynamics (MD) simulations, and MM-GBSA calculations were performed. Structure–activity relationship (SAR) study was discussed to study the influence of altering the size, type, and flexibility of the α-substituent to the carboxamide on the anti-SARS-CoV-2 activity.