Synthesis, SARS-CoV-2 main protease inhibition, molecular docking and in silico ADME studies of...

Seven furanochromene-quinoline derivatives containing a hydrazone linker were synthesized by condensing a furanochromene hydrazide with quinoline 2-, 3-, 4-, 5-, 6-, and 8-carbaldehydes, including 8-hydroxyquinoline-2-carbaldehye. Structure-activity correlations were investigated to determine the influence of the location of the hydrazone linker on the quinoline unit on SARS-CoV-2 M^pro enzyme inhibition. The 3-, 5-, 6- and 8-substituted derivatives showed moderate inhibition of SARS-CoV-2 M^pro with IC₅₀ values ranging from 16 to 44 μM. Additionally, all of the derivatives showed strong interaction with the SARS-CoV-2 M^pro substrate binding pocket, with docking energy scores ranging from -8.0 to -8.5 kcal/mol. These values are comparable to that of N3 peptide (-8.1 kcal/mol) and more favorable than GC-373 (-7.6 kcal/mol) and ML-188 (-7.5 kcal/mol), all of which are known SARS-CoV-2 M^pro inhibitors. Furthermore, in silico absorption, distribution, metabolism, and excretion (ADME) profiles indicate that the derivatives have good drug-likeness properties. Overall, this study highlights the potential of the furanochromene-quinoline hydrazone scaffold as a SARS-CoV-2 M^pro inhibitor.