Spectroscopic and single-crystal X-ray diffraction studies of enantiomeric copper(II) Schiff base one-dimensional coordination polymers with 4-(2-aminoethyl)benzenesulfonamide appendage: Comprehensive biological evaluation (DNA binding, cleavage, superoxide dismutase mimetic activity, topoisomerase I inhibition and cytotoxicity)

New chiral Cu(II)-based one-dimensional coordination polymers [l-C25H27CuN3O6S] (1a) and [d-C25H27CuN3O6S] (1b) were designed and synthesized by in situ reaction of Schiff base (o-vanillin and l-/d-phenylalanine) and appended ligand 4-(2-aminoethyl)benzenesulfonamide incorporated with Cu(II) ion. The enantiomeric complexes 1a and 1b were fully characterized using various spectroscopic techniques and single-crystal X-ray diffraction studies. The enantiomeric analogues 1a and 1b crystallized in chiral monoclinic P21 space group with z = 2 exhibiting a distorted square pyramidal environment around Cu(II) metal centre coordinated to N2O3 donor atoms with apical position occupied by adjacent bridging carboxylate oxygen, resulting in one-dimensional polymeric chain structures. Comprehensive biological studies of 1a and 1b (DNA binding, superoxide dismutase (SOD), topoisomerase I and cytotoxic activity) were performed which revealed that 1a showed better prospects as a therapeutic drug candidate as compared to 1b as quantified by their comparative DNA binding (K-b, K and K-sv values), SOD mimetic activity (IC50 values of 0.160 and 0.198, respectively) and anticancer properties.