Synthesis of new dithiocarbazate Sn(IV) complex; investigation of the crystalline structure and cytotoxic activity

Abstract

Metal complexes of S-alkyldithiocarbazates comprise an important class of compounds due to the interesting physical and chemical properties and also play significant role in biological systems. A new Sn(IV) complex, [SnCl2L.DMSO] (Fig. 1) [L: S-ethyl¬-3-(2-hydroxy¬phenyl)methylene¬dithiocarbazate)] (sedtc), is synthesized and characterized using single crystal X-ray diffraction analysis, mass spectrometry and spectroscopic techniques such as IR, 1H- and 13C-NMR. Compound 1 crystallizes in the triclinic system with P space group. The X-ray diffraction data revealed a distorted octahedral structure where the sedtc tridentate ONS ligand is coordinated to the metal ion via phenolic oxygen, iminic nitrogen, and thioenolate sulfur donor atoms. In this compound the two chlorine atoms are arranged cis relative to each other (96.81(3)º). The H2L ligand and one chlorine atom are located at the equatorial position and the other chlorine atom and DMSO solvent occupied the axial position. The adjacent molecules in this compound form dimers with ten-members graph set, (10), by a pairwise hydrogen bond H7-C7i···Cl2 (2.819 Å) (Symm. Code i: 2-x, 1-y, 1-z). The dimer form one-dimensional chain along the ac plane bisector through the C10-H10C···π (3.397 Å) and H12B-C12···Cl2 (2.868 Å) interactions. Moreover, invitro cytotoxicity of the complex against the MCF-7 (Human Breast cancer cell) and Hela (Human cervical cancer cell) cells are assayed by MMT method. Cytotoxicity study shows that ligand coordination to the metal increases cytotoxic activity relative to the free ligand and the complex has significant activity against human cervical cancer cell line.