Potentially cytotoxic new copper(ii) hydrazone complexes: synthesis, crystal structure and biological properties

Abstract

A new set of penta-coordinated copper(II) hydrazone complexes containing solvated methanol were synthesized by reacting the hydrazone ligands, 2-acetylpyridine benzoyl hydrazone (HL1) and 2-acetylpyridine thiophene-2-carboxylic acid hydrazone (HL2), with [CuCl2(DMSO)2] and characterized by different spectral methods. Single crystal X-ray diffraction studies of the complexes revealed that both of them, [CuCl(L1)(MeOH)] (1) and [CuCl(L2)(MeOH)] (2), have square pyramidal geometry around the cupric ion, in which the hydrazone is coordinated through NNO atoms along with a molecule of methanol in the apical position. Interaction of the ligands HL1 and HL2 along with the corresponding copper complexes 1 and 2 with calf thymus DNA (CT-DNA) has been estimated by absorption and emission titration methods which revealed that the compounds interacted with CT-DNA through intercalation. Binding of the compounds, i.e., free ligands and complexes (1) and (2) with bovine serum albumin (BSA) protein investigated using UV-visible, fluorescence and synchronous fluorescence spectroscopic methods indicated that there occurred strong binding of copper complexes to BSA over the ligands. Further, the cytotoxicity of the compounds examined in vitro on a panel of cancerous cell lines such as a human cervical cancer cell line (HeLa), a pancreatic cancer cell line (PANC-1), an Ehrlich ascites cancer cell line (EAC) and Dalton's lymphoma ascitic cancer cells (DLA) and a normal mouse embryonic fibroblasts cell line (NIH3) demonstrated that the complexes 1 and 2 possessed superior cytotoxicity than that of well-known commercial anticancer drug cisplatin to the tumor cells but are less toxic to the normal cell line and have emerged as potential candidates for further studies.

Synthesis and Spectroscopic Investigations of Schiff Bases Transition Metal Complexes of Copper(II), Cobalt(II) and Nickel(II)

“…These complexes show oxidase biometric catalytic activity, anticancer and antimicrobial activities [6][7][8][9][10][11]. The study of Schiff bases and their complexes has become a focal point of interest for chemists in recent years, not only for their several structural features, but due to their potential application in various fields [12][13][14][15].…”

Synthesis, Structures and Antimicrobial Activity of Chloro- And Fluoro-Substituted Thiocarboxyhydrazones

“…17 There is no obvious charge delocalization in the molecules, as evidenced by the typical C-N single bonds between atoms C8 and N3. Symmetry codes: (1) and Cg (2) are the centroids of C1-C2-C3-C4-C5-C6 (1) and C1-C2-C3-C4-C5-C6 (3), respectively.…”

Synthesis, characterization and crystal structures of hydrazone compounds derived from isonicotinohydrazide

“…Cg (1) and Cg (2) are the centroids of N3-C11-C10-C9-C13-C12 and C1-C6 of 1; Cg(3), Cg (4),Cg (5)and Cg (6) are the centroids of N3-C11-C10-C9-C13-C12, C1-C6, N6-C24-C23-C22-C26-C25, and C14-C19 of 2.…”

“…It can react with aldehydes to form isonicotinohydrazones, which show interesting biological activities [1][2][3][4]. Moreover, isonicotinohydrazone compounds usually possess three or more donor atoms, which can readily form complexes with various metal atoms [5][6][7][8][9][10][11][12]. Recently, we found that halido-substituted hydrazones have potential antimicrobial activities [13].…”