Unraveling the antioxidant effect of new quinoline epoxides: Synthesis, crystal structure from PXRD, HS analysis and molecular docking's binding modes

Quinoline derivatives are significant in organic and medicinal chemistry due to their versatile applications, especially in pharmacology. In this work, we report the synthetic pathways and structural characterization of four new quinoline epoxides derived from 2-chloro-3-formylquinoline, namely 2-chloro-3-(oxiran-2-yl)quinoline (4a), 2-chloro-6-methoxy-3-(oxiran-2-yl)quinoline (4b), 2-chloro-5,8-dimethyl-3(oxiran-2-yl)quinoline (4c) and 2-chloro-6,8-dimethyl-3(oxiran-2-yl)quinoline (4d), by using a stepwise approach involving the preparation of acetanilides, their transformation into quinoline derivatives and subsequent epoxidation. These compounds were characterized by spectroscopic FT-IR, 1HNMR , 13CNMR , 1H/1HCOSY, HSQC, high-resolution mass spectrometry (HRMS) and powder X-ray diffraction (PXRD) techniques. We have provided herein insights into the structural features of the studied compounds by analyzing their Hirshfeld surfaces and most prominent intermolecular interactions. Furthermore, we have investigated their in vitro biological implications as antioxidant agents and highlighted their in silico binding modes by carrying out molecular docking calculations against human peroxiredoxin (3MNG).