Two new Mg3(II)-cluster-based coordination polymers: their synthesis, crystal structures and inhibiting activity on the human spinal tumor cells

Abstract

In this study, two new Mg3-cluster-based coordination polymers are obtained via a one-pot solvothermal reaction of Mg(NO3)2·6H2O with two C3-symmetrical N-rich polycarboxylic acid organic ligands with different ligand flexibilities, which show interesting structural diversity. The complex 1 with the formula of [Mg3(tatb)2(MeOH)2(DMA)2](DMA)2 (H3tatb=4,4′,4″-s-triazine-2,4,6-triyl-tribenzoic acid, DMA=N,N-dimethylacetamide) is constructed from the linear Mg3 cluster, which is further extended via the rigid tatb3− ligand to afford a 2D layered framework. In comparison, the complex 2 with the formula of [Mg3(tatab)2(H2O)6](DMA)2 (H3tatab=4,4′,4″-s-triazine-1,3,5-triyltri-p-aminobenzoic acid) is built from the similar Mg3 cluster but shows a 3D framework due to the flexibility of the tatab3− ligand. Furthermore, the in vitro anticancer activity is evaluated against human spinal tumor lines U-266 via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

Keywords

• coordination polymer
• lung cancer cell
• n-rich ligand