Shedding Light on the Synthesis, Crystal Structure, Characterization, and Computational Study of Optoelectronic Properties and Bioactivity of Imine derivatives

Two imine compounds
named as (E)-2-(((3,4-dichlorophenyl)­imino)­methyl)­phenol (DC2H) and (E)-4-(((2,4-dimethylphenyl)­imino)­methyl)­phenol (DM4H) are synthesized, and their crystal structures are verified
using the single-crystal X-ray diffraction (XRD) technique. The crystal
structures of the compounds are compared with the closely related
crystal structures using the Cambridge Structural Database (CSD).
The crystal packing in terms of intermolecular interactions is fully
explored by Hirshfeld surface analysis. Void analysis is carried out
for both compounds to check the strength of the crystal packing. Furthermore,
a state-of-the-art dual computational technique consisting of quantum
chemical and molecular docking methods is used to shed light on the
molecular structure, optoelectronic properties, and bioactivity of
indigenously synthesized compounds. The optimized molecular geometries
are compared with their counterpart experimental values. Based on
previous reports of biofunctions of the indigenously synthesized imine
derivatives, they are explored for their potential inhibition properties
against two very crucial proteins (main protease (Mpro)
and nonstructural protein 9 (NSP9)) of SARS-CoV-2. The calculated
interaction energy values of DC2H and DM4H with Mpro are found to be −6.3 and −6.6
kcal/mol, respectively, and for NSP9, the calculated interaction energy
value is found to be −6.5 kcal/mol. We believe that the current
combined study through experiments and computational techniques will
not only pique the interest of the broad scientific community but
also evoke interest in their further in vitro and in vivo investigations.