New tetrahedral, square-pyramidal, trigonal-bipyramidal and octahedral organotin(IV) 4-ethoxycarbonylpiperazine-1-carbodithioates: Synthesis, structural properties and biological applications

Novel diphenyltin(IV) complexes with carboxylato N-functionalized 2-quinolone ligands: Synthesis, characterization and in vitro anticancer studies

Three new diphenyltin(IV) complexes, bis(3-(4-methyl-2-oxoquinolinyl-1(2H)-yl)propanoato)diphenyltin(IV) (1), bis(2-(4-methyl-2-oxoquinolin-1(2H)-yl)ethanoato)diphenyltin(IV) (2), and bis(2-(4-hydroxy-2-oxoquinolin-1(2H)-yl)ethanoato)diphenyltin(IV) (3), were synthesized and characterized by elemental microanalysis, FT-IR spectroscopy, and multinuclear (1H, 13C and 119Sn) NMR spectroscopy. Crystal structure of ligand precursor, 2-(4-methyl-2-oxoquinolinyl-1-(2H)-yl)acetic acid (HL2), has been determined by X-ray diffraction studies. Asymmetric bidentate coordination of the carboxylato ligands and skew trapezoidal structures are assumed for the synthesized complexes. In vitro anticancer activity of the synthesized diphenyltin(IV) complexes was evaluated against three human: MCF-7 (breast adenocarcinoma), A375 (melanoma), HCT116 (colorectal carcinoma), and three mouse tumor cell lines: 4T1 (breast carcinoma), B16 (melanoma), CT26 (colon carcinoma) using MTT and CV assays. The IC50 values fall in the range from 0.1 to 3.7 μM. Flow cytometric analysis and fluorescent microscopy suggest that complex 1 induces caspase-dependent apoptosis followed with strong blockade of cell division in HCT116 cells. Since complex 1 showed ROS/RNS scavenging potential mentioned cytotoxicity was not connected with oxidative stress.

Therapeutic properties of organotin complexes with reference to their structural and environmental features

Organotin complexes are being extensively studied and screened for their therapeutic potential. Although many recent advances and achievements in this field have been made, the exact mode of action of these complexes is yet to be unveiled. In the present review, an attempt has been made to correlate the therapeutic properties of organotin complexes with their structural features and the environment in which these interact with biological systems. The mechanism, various modes of interaction with biological systems, and physiological target sites of organotin complexes have been highlighted as well.