Synthesis, molecular and supramolecular structure aspects and biological evaluations of a novel [Ag2(phthalazine)(NO3)2]n 3D coordination polymer

Abstract

The novel [Ag2(phth)(NO3)2]n 3D coordination polymer of phthalazine (phth) ligand was synthesized by reaction of silver nitrate and the hydrazonophthalazine (E)-2-(1-(2-(Phthalazin-1-yl)hydrazono)ethyl)phenol. The molecular and supramolecular structural aspects of the complex were investigated using single crystal X-ray diffraction combined with Hirshfeld calculations. There are two crystallographically independent Ag1 and Ag2 sites having completely different coordination environments. Ag1 is tetra-coordinated with mixed organic and inorganic AgN2O2 coordination sphere from two phth ligands and one bidentate nitrate ion. The two phth ligands are bridging two Ag1 sites leading to significantly short Ag1-Ag1 distance of 3.152(7) Å indicating the presence of argentophillic interactions. The Ag2 site is hexa-coordinated with four nitrate groups hence, having only inorganic AgO6 coordination environment. The nitrate groups acting as connectors between the Ag-sites leading to the 3D coordination polymer. A novel T12 coordination mode for one of the NO3¯ group was detected. Based on Hirshfeld calculations, the O…H (37.8%), C…O (4.7%) and C…C (3.5%) as well as Ag-O (13.2%) interactions have great importance in the supramolecular structure of the studied complex. The [Ag2(phth)(NO3)2]n complex showed broad-spectrum activity against both bacteria and fungus. It showed significant cell growth inhibition against lung carcinoma A-549 cell line (IC50 of 4.32 ± 0.86 µg/mL) compared to Doxorubicin (0.95 ± 0.17 µg/mL).