Unconventional DNA-relevant π–stacked Hydrogen bonded array involving supramolecular guest benzoate dimer and Cooperative anion–π/π–π/π–anion contacts in Coordination Compounds of Co(II) and Zn(II) phenanthroline: Experimental and Theoretical studies
Two new coordination compounds, viz., [Co(phen)(bz)(H2O)3] bz (1) and [Zn(phen)2(H2O)Cl] Cl bzH∙2H2O (2) (phen = 1,10-phenanthroline, bz = benzoate, bzH= benzoic acid) were synthesized from purely aqueous media, and characterized using elemental analysis, spectroscopic (IR, UV‒Vis‒NIR) and single crystal X-ray diffraction techniques. In the crystal structures of 1 and 2, supramolecular networks have been built up involving association of O‒H∙∙∙O, C‒H∙∙∙O, π‒π stacking interactions. The enclatharation of the guest bzH molecule in the host monomers of Zn(II) brings rigidity to the structure of compound 2. Theoretical investigations have been carried out to rationalize interesting supramolecular assemblies that include cooperative anion–π/π–π/π–anion in 1 and DNA-releavant HB-array•••π/π–π/π–HB-array interactions in 2, which have been characterized using NCI plot and Bader’s theory of “atoms-in-molecules”. The complexes significantly inhibit cell viability by inducing apoptotic cell death in Dalton’s lymphoma (DL) cell line with negligible cytotoxicity in normal cells. The molecular docking study and pharmacophore features reveal that the compounds 1 and 2 interact and accommodate well in the active site of anti-apoptotic proteins. Antimicrobial studies against a few pathogenic organisms suggest that the compounds are active against Gram-positive and Gram-negative bacteria and have relatively better antibacterial activity in comparison to phen.