A new Pb(II)-based coordination polymer constructed by 5-((4-carboxyphenoxy)methyl)benzene-1,3-dioic acid and N-donor co-ligand: crystal structure and anti-glioma activity

A new lead(II)-organic architecture [Pb(HL) (dipyrido[3,2-a:2',3'-c]phenazine (dppz))](H2O)(2) (1) was successfully prepared under hydrothermal conditions by using organic-acid linker 5-((4-carboxyphenoxy)methyl) benzene-1,3-dioic acid (H3L) and N-donor chelating ligand dppz. The as-prepared complex was characterized by single-crystal X-ray structural analysis, powder X-ray diffraction (PXRD), and elemental analyses, which reveals that complex 1 shows a one-dimensional (1D) chain-like structure that is further extended to the 3D supermolecular network through H-bond and pi-pi interactions. Complex 1 was transformed to the nanoscale regime (ca. 190 nm) by mechanical grinding to yield the nano-1, maintaining its structure and crystallinity. Furthermore, the anticancer activity of the nano-1 toward the human neuroglioma cells (U251, U87, SHG-44, and A172) was evaluated via the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay.