Synthesis, Crystal Structure, and Cytotoxic Activity of a Novel Eight-Coordinated Dinuclear Ca(II)-Schiff Base Complex

A novel eight-coordinated dinuclear Ca(II) complex, [Ca2(L)2(H2O)10]·H2O (L = 4-formylbenzene-1,3-disulfonate-3-pyridinecarboxylic hydrazone) (1), was synthesized by the reaction of 3-pyridinecarboxylic hydrazide, disodium 4-formylbenzene-1,3-disulfonate, and Ca(ClO4)2·4H2O in ethanol-water solution (v:v = 3:1) at 50 ◦C. Complex 1 was characterized by elemental analysis, IR, 1H-NMR, 13C-NMR, and X-ray single crystal diffraction analysis. Dinuclear Ca(II) complex 1 belongs to triclinic, space group P-1 with a = 7.186(3) Å, b = 11.978(5) Å, c = 12.263(5) Å, α = 90.318(5)◦, β = 91.922(5)◦, γ = 96.797(5)◦, V = 1047.5(8) Å3, Z = 1, Dc = 1.685 mg·m−3, μ = 0.572 mm−1, F(000) = 552, and final R1 = 0.0308, ωR2 = 0.0770. Dinuclear Ca(II) molecules form a 1D chained structure by π–π stacking interaction. The 1D chains form a 3D framework structure by the π–π stacking interaction and hydrogen bonds. The in vitro cytotoxic activity activity of 1 against HL-60 and MLTC-1 was also investigated.