Synthesis and Biological Evaluations of N-(4-Substituted Phenyl)-7-Hydroxy-4-Methyl-2-Oxoquinoline-1(2H)-Carbothioamides

In continuance of search for new compounds we report herein the expedient and optimized synthesis of a series of N-(4-substituted phenyl)-7-hydroxy-4-methyl-2-oxoquinoline-1(2H)-carbothioamides (5a-g) in good yields. The anticancer and antioxidant activities were determined as per the standard protocol. Nearly 5 dozens of cancer cell lines derived from nine different panels are used in the study and anticancer activity was calculated as growth percents (GPs) and percent growth inhibitions (%GIs). The molecular docking simulation against one of the potential targets i.e., epidermal growth factor receptor (EGFR) was done to find the putative approach of action of the title compounds 5a-g. N-(4-Nitrophenyl)-7-hydroxy-4-methyl-2-oxoquinoline-1(2H)-carbothioamides (5b) showed the most promising anticancer activity with higher sensitivity against UO-31, HOP-92, CAKI-1, LOX IMVI and T-47D with GPs of 66.65, 72.63, 85.80, 86.11, and 86.96 respectively. The compound 5b exhibited antioxidant activity with an IC₅₀ value of 15.21 ± 1.52 µM. The molecular docking simulation showed an efficient binding of compound 5b against the activity site of EGFR with two H-bond interactions with the residues Gln791 and Thr854, a π-π stacking and a π-cationic interaction with the residue Phe856, while a salt bridge interaction with the residue Lys745.