Chirality‐Induced Variation in Interaction of Two Similar Copper(II) Coordination Polymers with Calf Thymus DNA: Exploration of Their Antimicrobial Activity and Cytotoxicity

Abstract

AbstractTwo polynuclear end‐to‐end dicyanamide (dca) bridged copper(II) Schiff base complexes [Cu(L1)(μ1,5‐dca)]n (1) and [Cu(L2)(μ1,5‐dca)]n (2) {[HL1=(1‐(2‐(diethylamino)ethylimino)ethyl) naphthalene‐2‐ol] and [HL2=(1‐(2‐(dimethylamino)ethylimino)methyl) naphthalene‐2‐ol]} were synthesized and X‐ray characterized. Complex 1 crystallizes in chiral space group C2 and complex 2 crystallizes in achiral space group P21/c. Interactions of both complexes with calf thymus DNA (CT DNA) were studied by UV‐vis and circular dichroism spectroscopy. Molecular docking studies were also carried out for both complexes to find their binding affinity using Alpha PMI as the placement methodology. Although docking studies indicated that the binding constants of both complexes with CT DNA were more or less same, UV‐Vis spectral data indicated that the binding constant of complex 1 with CT DNA is considerably large compared to that of complex 2. As complex 1 is chiral and complex 2 is achiral, it may be concluded that the chirality of complex 1 played very significant role to binding of chiral DNA molecule. The antimicrobial activity were estimated by the determination of the minimal inhibitory concentration (MIC) using the broth microdilution method. The complexes showed high in vitro cytotoxicity against MDA‐MB 468 cells.