New metal chelate constructed from Ni(NCS)2 and 1,2-diphenyl-1,2-bis((phenyl(pyridin-2-yl)methylene)hydrazono)ethane

Evaluation of the antitumor activity of a series of the pincer-type metallocomplexes produced from isonicotinohydrazide derivative

In this work we report on the antitumor properties of a series of pincer-type metallocomplexes [Hg₂(HL-keto)Cl₄]_n (1), [Hg(HL-keto)I₂] (2) and [Mn(HL-zwitterion)Cl₂]∙MeOH (3∙MeOH), derived from N'-(1-(pyridin-2-yl)ethylidene)isonicotinohydrazide (HL) and corresponding metal salts. The Hg(II) and Mn(II) salts are chelated by the keto (HL-keto) or zwitterionic (HL-zwitterion) form of HL, respectively. The cytotoxic effects of these compounds have been accessed against lung adenocarcinoma (A549) and hepatocellular carcinoma (HepG2 and Huh7) cell lines. Complexes 1 and 2 were found to be most efficient against the cell line Huh7 with IC₅₀ value of 2.56 and 9.90 μM, respectively, while they exhibit moderate activity towards cell lines A549 and HepG2, as evidenced from IC₅₀ values in the range 27.98-56.99 μM. Complex 3∙MeOH is less efficient towards all the three cell lines with relatively high IC₅₀ values. The mechanisms of the metallocomplexes killing the aforementioned cells were elucidated by flow cytometry, colony formation and polymerase chain reaction (PCR) analysis of apoptosis related expression of the genes. The results of the cytotoxic effects and antitumor activity on different cell lines are affected by the metal nature and the presence of the coordinated halide.

Synthesis, Crystal Structures, and Antimicrobial and Antitumor Studies of Two Zinc(II) Complexes with Pyridine Thiazole Derivatives

Two pyridine thiazole derivatives, namely, 4-(pyridin-2-yl)-2-(2-(pyridin-2-ylmethylene)hydrazinyl)thiazole (L1) and 4-(pyridin-3-yl)-2-(2-(pyridin-4-ylmethylene)hydrazinyl)thiazole (L2), were afforded by a cyclization reaction between α-haloketone and thioamide, and their Zn(II) complexes were prepared by the reaction of ligands and corresponding metal salts, respectively, and characterized by X-ray diffraction and elemental analysis. Both crystals were obtained by ether diffusion and crystallized in a monoclinic system. The in vitro antimicrobial activity of the Zn(II) complexes and ligands was screened using the microplate reader method, and in vitro antitumor activities of the complexes were evaluated by MTT, with a view to developing new improved bioactive materials with novel properties. The biological activity studies of the compounds showed that the metal complexes were more active than the free ligands, and some compounds had absolute specificity for certain bacteria or cancer cell lines.