Synthesis, Structural Investigations, and Potential Antimicrobial and Anticancer Activity of Mononuclear Zn(II) and Cd(II) Complexes Decorated by Morpholine/Pyrazole s-Triazine Ligand

The structure and biological diversities of [Zn(BPTMorph)(H2O)(3)](ClO4)(2) (1), [Zn(BPTMorph)(NO3)(2)] (2), and [Cd(BPTMorph)(NO3)(2)] (3) complexes were described. In all complexes, the Zn(II) and Cd(II) ions are coordinated with one 4-(4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazin-2-yl)morpholine (BPTMorph) molecule as a pincer NNN-chelate. The rest of the coordination sphere was found to depend on the type of anion. In 1, there are three coordinated water molecules leading to a distorted octahedral geometry around Zn(II). In 2 and 3, there are two coordinated NO3- groups that differ in their coordination modes. The two NO3- groups are monodentate in 1 and bidentate in 3. Hence, the coordination numbers of Zn(II) and Cd(II) are 5 and 7, respectively. Supramolecular structure investigations indicated the importance of O<middle dot><middle dot><middle dot>H contacts in the molecular packing. The percentages of O<middle dot><middle dot><middle dot>H contacts are 35.4%-36.1%, 44.8%, and 39.7% in complexes 1-3, respectively. The energy breakdown for the intermolecular interactions was performed using energy framework analysis to explore the forces that dominate these interactions. Anticancer activity of complexes 1-3 and BPTMorph against HepG-2, MCF-7, and A-549 cancerous cells was presented. The best result is found for complex 3 against A-549 where the IC50 is 2.77 +/- 0.26 mu g/mL and selectivity index is 12.5 although the corresponding values for BPTMorph are 32.39 +/- 2.82 mu g/mL and 2.7, respectively. In addition, 3 outperformed the anticancer drug cis-platin against all cell lines. The antimicrobial activity of 3 is the best compared to 1, 2, and BPTMorph. Interestingly, 3 showed antibacterial efficiency comparable to gentamycin against Proteus vulgaris.