(N,N-Di-allyl-dithio-carbamato-κ2 S,S')tri-phenyltin(IV) and bis-(N,N-di-allyl-dithio-carbamato-κ2 S,S')di-phenyl-tin(IV): crystal structure, Hirshfeld surface analysis and computational study

Series of Organotin(IV) Compounds with Different Dithiocarbamate Ligands Induced Cytotoxicity, Apoptosis and Cell Cycle Arrest on Jurkat E6.1, T Acute Lymphoblastic Leukemia Cells

The discovery of cisplatin has influenced scientists to study the anticancer properties of other metal complexes. Organotin(IV) dithiocarbamate compounds are gaining attention as anticancer agents due to their potent cytotoxic properties on cancer cells. In this study, a series of organotin compounds were assessed for their toxic effects on the Jurkat E6.1 cell line. WST-1 assay was used to determine the cytotoxic effect of the compounds and showed that six out of seven organotin(IV) dithiocarbamate compounds exhibited potent cytotoxic effects toward T-lymphoblastic leukemia cells, Jurkat E6.1 with the concentration of IC₅₀ ranging from 0.67-0.94 µM. The apoptosis assay by Annexin V-FITC/PI staining showed that all tested compounds induced cell death mainly via apoptosis. Cell cycle analysis assessed using RNase/PI staining showed that organotin(IV) dithiocarbamate compounds induced cell cycle arrest at different phases. In conclusion, the tested organotin(IV) dithiocarbamate compounds demonstrated potent cytotoxicity against Jurkat E6.1 cells via apoptosis and cell cycle arrest at low IC₅₀ value. However, further studies on the mechanisms of action are required to probe the possible potential of these compounds on leukemia cells before they can be developed into anti-leukemic agents.

Triphenyltin(IV) dithiocarbamate compound induces genotoxicity and cytotoxicity in K562 human erythroleukemia cells primarily via mitochondria-mediated apoptosis

The novel di-and triphenyltin(IV) dithiocarbamate compounds represented as R_nSnL₂ (where R = C₄H₉, C₆H₅; n = 2,3; L = N,N-dithiocarbamate), Ph₂Sn(N,N-diisopropyldithiocarbamate) (OC1), Ph₃Sn(N,N-diisopropyldithiocarbamate) (OC2), Ph₂Sn(N,N-diallyldithiocarbamate) (OC3), Ph₃Sn(N,N-diallyldithiocarbamate) (OC4), and Ph₂Sn(N,N-diethyldithiocarbamate) (OC5) were assessed for their cytotoxicity in K562 human erythroleukemia cells. All compounds inhibited the growth of cells at low micromolar concentrations (<10 μM), and the mechanism underlying their antiproliferative effects on K562 cells was apoptosis, as corroborated by the exposure of plasma membrane phosphatidylserine. OC2, which showed the most promising antiproliferative activity, was selected for further analyses. The results demonstrated that OC2 induced apoptosis in K562 cells via an intrinsic mitochondrial pathway triggered upon DNA damage, an early apoptotic signal. Subsequently, OC2 produced excessive intracellular reactive oxygen species. The role of oxidative stress was corroborated by the significant reduction in GSH levels and percentage of apoptosis in NAC-pretreated cells. OC2 could arrest the cell cycle progression in the S phase. These new findings elucidate the antiproliferative potential of OC2 in the K562 human erythroleukemia cells and warrant further investigation, specifically to determine the exact signaling pathway underlying its antileukemic efficacy.

On the Coordination Role of Pyridyl-Nitrogen in the Structural Chemistry of Pyridyl-Substituted Dithiocarbamate Ligands

A search of the Cambridge Structural Database was conducted for pyridyl-substituted dithiocarbamate ligands. This entailed molecules containing both an NCS2− residue and pyridyl group(s), in order to study their complexation behavior in their transition metal and main group element crystals, i.e., d- and p-block elements. In all, 73 different structures were identified with 30 distinct dithiocarbamate ligands. As a general observation, the structures of the transition metal dithiocarbamates resembled those of their non-pyridyl derivatives, there being no role for the pyridyl-nitrogen atom in coordination. While the same is true for many main group element dithiocarbamates, a far greater role for coordination of the pyridyl-nitrogen atoms was evident, in particular, for the heavier elements. The participation of pyridyl-nitrogen in coordination often leads to the formation of dimeric aggregates but also one-dimensional chains and two-dimensional arrays. Capricious behaviour in closely related species that adopted very different architectures is noted. Sometimes different molecules comprising the asymmetric-unit of a crystal behave differently. The foregoing suggests this to be an area in early development and is a fertile avenue for systematic research for probing further crystallization outcomes and for the rational generation of supramolecular architectures.

Synthesis and cytotoxic activity of organotin(IV) diallyldithiocarbamate compounds as anticancer agent towards colon adenocarcinoma cells (HT-29)

Context

Diphenyltin(IV) diallyldithiocarbamate compound (Compound 1) and triphenyltin(IV) diallyldithiocarbamate compound (Compound 2) are two newly synthesised compounds of organotin(IV) with diallyldithiocarbamate ligands.

Objective

To assess the cytotoxic effects of two synthesised compounds against HT-29 human colon adenocarcinoma cells and human CCD-18Co normal colon cells.

Materials and methods

Two successfully synthesised compounds were characterised using elemental (carbon, hydrogen, nitrogen, and sulphur) analysis, Fourier-Transform Infrared (FTIR), and ¹H, ¹³C ¹¹⁹Sn Nucleus Magnetic Resonance (NMR) spectroscopies. The single-crystal structure of both compounds was determined by X-ray single-crystal analysis. The cytotoxicity of the compounds was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazholium bromide (MTT) assay upon 24 h of treatment. While the mode of cell death was determined based on the externalisation of phosphatidylserine using a flow cytometer.

Results

The elemental analysis data of the two compounds showed an agreement with the suggested formula of (C₆H₅)₂Sn[S₂CN(C₃H₅)₂]₂ for Compound 1 and (C₆H₅)₃Sn[S₂CN(C₃H₅)₂] for Compound 2. The two major peaks of infrared absorbance, i.e., ν(C = N) and ν(C = S) were detected at the range of 1475–1479 cm⁻¹ and 972–977 cm⁻¹, respectively. The chemical shift of carbon in NCS₂ group for Compound 1 and 2 were found at 200.82 and 197.79 ppm. The crystal structure of Compound 1 showed that it is six coordinated and crystallised in monoclinic, P2₁/c space group. While the crystal structure of Compound 2 is five coordinated and crystallised in monoclinic, P2₁/c space group. The cytotoxicity (IC₅₀) of the two compounds against HT-29 cell were 2.36 μM and 0.39 μM. Meanwhile, the percentage of cell death modes between 60% and 75% for compound 1 and compound 2 were mainly due to apoptosis, suggesting that both compounds induced growth arrest.

Conclusion

Our study concluded that the synthesised compounds showed potent cytotoxicity towards HT-29 cell, with the triphenyltin(IV) compound showing the highest effect compared to diphenyltin(IV).

A Structural Survey of Poly-Functional Dithiocarbamate Ligands and the Aggregation Patterns They Sustain

An overview is presented of the crystal structures of transition metal, main group element, and lanthanide compounds containing poly-functional dithiocarbamate ligands, namely species containing two or more connected NCS2− residues. In all, there are 40 different ligands of this type that have been characterised crystallographically in their heavy-element compounds with up to six NCS2− residues; all are bridging. In most cases, the resulting aggregates are zero-dimensional, often di-nuclear, but aggregates of up to 36 metal (gold) atoms are noted. There are smaller numbers of one-, two-, and three-dimensional architectures sustained by poly-functional dithiocarbamate ligands in their respective crystals. The survey highlights the opportunities afforded by this generally under-studied class of ligand.