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Organotin complexes are recognized as the biologically active compounds in inducing cancerous cells death at very low doses. To date, organotin compounds currently appear among the most potent candidates in research related to the new anticancer drugs. In this study, new organotin(IV) N-butyl-N-phenyldithiocarbamate compounds have been successfully synthesized between the reaction of N-butylaniline amine with organotin(IV) chloride in 1:2/1:1 molar ratio. All compounds were characterized using the elemental analysis, FT-IR and NMR spectroscopy. The single crystal structure was determined by X-ray single crystal analysis. The elemental analysis showed good agreement with the suggested formula (C4H9)2Sn[S2CN(C4H9)(C6H5)]2 (Compound 1 and 2), (C6H5)2Sn[S2CN(C4H9)(C6H5)]2 (Compound 3) and (C6H5)3Sn[S2CN(C4H9)(C6H5)] (Compound 4). The important infrared absorbance peaks, v (C = N) and v(C = S) were detected in range between 1457-1489 cm(-1) and 951-996 cm(-1), respectively. The chemical shift of carbon in NCS2 group obtained from 13C NMR was found in range 198.86-203.53 ppm. The crystal structure of compound 4 showed that the dithiocarbamate ligand coordinates in a monodentate fashion. It crystallized in monoclinic P2(1)/n space group with the crystal cell parameter: a = 10.0488(1) angstroms, b = 18.0008(2) angstroms, c = 15.2054(2) angstroms, beta = 102.442(1) degrees and R = 0.044. The cytotoxicity (IC50) of these compounds against Jurkat E6.1 and K-562 leukemia cells were in the range between 0.4-0.8 and 1.8-5.3 microM, respectively as assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazholium bromide (MTT) assay. In conclusion, our study demonstrate that all compounds showed potent cytotoxicity towards both cell lines tested with the triphenyltin(IV) compound displayed the greatest effect.

Ammonia and chemical oxygen demand (COD) were the most two problematic parameters in the landfill leachate. In this study, a new composite adsorbent derived from rice husk ash waste is evaluated with respect to its ability to remove these contaminants from synthetic leachate. Results indicate that the new composite adsorbent is able to adsorb both ammonia and COD. It has a higher adsorption capacity for ammonia (Q = 2.2578 mg/g) and an almost equal adsorption capacity for COD (Q = 2.8893) when compared with commercially activated carbon. The adsorption kinetics of this new product for ammonia and COD were primarily represented by the pseudo second-order mechanism. The overall adsorption rate of the ammonia and COD adsorption processes appears to be determined by chemisorption process. The regenerated composite adsorbent indicated higher adsorption capacities of ammonia and COD, i.e. 12.9366 mg/g and 3.1162 mg/g, respectively.

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Organotin(IV) compounds have wide applications in industrial and agricultural fields owing to their ability to act as poly(vinyl chloride) stabilizers and catalytic agents as well as their medicinal properties. Moreover, organotin(IV) compounds may have applications as antitumor, anti-inflammatory, antifungal, or antimicrobial agents based on the observation of synergistic effects following the binding of their respective ligands, resulting in the enhancement of their biological activities. In this review, we describe the antiproliferative activities of organotin(IV) compounds in various human cancer cell lines based on different types of ligands. We also discuss the molecular mechanisms through which organotin(IV) compounds induce cell death via apoptosis through the mitochondrial intrinsic pathway. Finally, we present the mechanisms of cell cycle arrest induced by organotin(IV) compounds. Our report provides a basis for studies of the antitumor activities of organotin(IV) compounds and highlights the potential applications of these compounds as anticancer metallodrugs with low toxicity and few side effects.

The renovation of a building will certainly affect the quality of air in the vicinity of where associated activities were undertaken, this includes the quality of air inside the building. Indoor air pollutants such as particulate matter, heavy metals, and fine fibers are likely to be emitted during renovation work. This study was conducted to determine the concentration of heavy metals, asbestos and suspended particulates in the Biology Building, at the Universiti Kebangsaan, Malaysia (UKM). Renovation activities were carried out widely in the laboratories which were located in this building. A low-volume sampler was used to collect suspended particulate matter of a diameter size less than 10 μm (PM₁₀) and an air sampling pump, fitted with a cellulose ester membrane filter, were used for asbestos sampling. Dust was collected using a small brush and scope. The concentration of heavy metals was determined through the use of inductively coupled plasma-mass spectroscopy and the fibers were counted through a phase contrast microscope. The concentrations of PM₁₀ recorded in the building during renovation action (ranging from 166 to 542 μg m⁻³) were higher than the value set by the Department of Safety and Health for respirable dust (150 μg m⁻³). Additionally, they were higher than the value of PM₁₀ recorded in indoor environments from other studies. The composition of heavy metals in PM₁₀ and indoor dust were found to be dominated by Zn and results also showed that the concentration of heavy metals in indoor dust and PM₁₀ in this study was higher than levels recorded in other similar studies. The asbestos concentration was 0.0038 ± 0.0011 fibers/cc. This was lower than the value set by the Malaysian Department of Occupational, Safety and Health (DOSH) regulations of 0.1 fibers/cc, but higher than the background value usually recorded in indoor environments. This study strongly suggests that renovation issues need to be considered seriously by relevant stakeholders within the university in order to ensure that the associated risks toward humans and indoor environment are eliminated, or where this is not feasible, minimized as far as possible.

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