Synthesis, crystal structural determination and in silco biological studies of 3,3′-ethane-1,2-diylbis(2-benzylidene-1,3-thiazolidin-4-one

A new thiazolidine derivative, 3,3′-ethane-1,2-diylbis(2-benzylidene-1,3-thiazolidin-4-one (4) was synthesized and the product obtained was characterized by NMR, IR and mass spectral studies, and the structure was confirmed by single crystal X-ray diffraction studies. The title compound crystallizes in the monoclinic space group P21/n, the unit cell parameters are a = 15.9505(8) Å, b = 6.6818(3) Å, c = 18.1799(9) Å, β = 94.249(2)° and Z = 4 at 150 K. In the title molecule, C20H18N4O2S2, the thiazolidine rings adopt a "pincer" conformation with the phenylimino substituents extending outwards on both sides. A layer structure is formed in the crystal by C—H···N and C—H···O hydrogen bonds. A Hirshfeld surface analysis was used to explore the nature of the intermolecular interactions in the crystal structure employing molecular surface contours and 2D fingerprint plots have been used to examine molecular shapes. The frontier orbital analysis shows that 4 should be more sensitive to a nucleophilic attack than an electrophilic attack. Molecular docking, followed by molecular dynamics simulation and MM-GBSA binding free energy was carried out to predict the binding affinity of 4 for α-amylase enzyme. These analyses revealed good intermolecular stability of the complex with stable high affinity intermolecular complex formation of high equilibrium nature.