Synthesis, theoretical calculation, and biological studies of mono- and diphenyltin(iv) complexes of n-methyl-n-hydroxyethyldithiocarbamate

In this study, chlorophenyltin(IV) [(C6H5)(Cl)Sn(L)2] and diphenyltin(IV) [(C6H5)2Sn(L)2] of N-methyl-N-hydroxyethyldithiocarbamate were prepared and characterized using various spectroscopic methods (FTIR, 1H, 13C, and 119Sn NMR) and elemental analysis. The FTIR and NMR spectral data, used to establish the structure of the compounds, showed the formation of the complexes via coordination to the two sulfur atoms from the dithiocarbamate ligand and the respective phenyltin(IV) derivatives. This coordination mode was further explored by DFT calculations, which showed that the bonding around the Sn center in [(C6H5)2Sn(L)2] was more asymmetric compared to the bonding around [(C6H5)(Cl)Sn(L)2]. However, the Sn–S bonds in [(C6H5)(Cl)Sn(L)2] were found to be more covalent than those in [(C6H5)2Sn(L)2]

Synthesis, computational and biological studies of alkyltin(IV) N-methyl-N-hydroxyethyl dithiocarbamate complexes

Methyltin(IV) of butyltin(IV)–N-hydroxyethyl dithiocarbamate complexes, represented as [(CH3)2Sn(L(OH))2] and [(C4H9)2Sn(L(OH))2] respectively were synthesized and characterized using spectroscopic techniques (1 H, 13C and 119Sn NMR) and elemental analysis. Both infrared and NMR data showed that, the complexes were formed via two sulphur atoms of the dithiocarbamate group. This mode of coordination was further supported by the DFT calculation, which suggested the formation of a distorted octahedral geometry around the tin atom. The complexes were screened for their antioxidant, cytotoxicity and anti-inflammatory properties. Four different assays including DPPH, nitric oxide, reducing power and hydrogen peroxides were used for the antioxidant studies, while an in vitro anti-inflammatory study was done using albumin denaturation assay. The complexes showed good antioxidant activity, especially in the DPPH assay. Butyltin(IV)–N-hydroxyethyl dithiocarbamate showed better cytotoxicity activity compared to methyltin(IV)–N-hydroxyethyl dithiocarbamate in the selected cell lines, which included KMST-6, Caco-2 and A549 cell lines. The anti-inflammatory activities revealed that the two complexes have useful activities better than diclofenac used as control drug

Organotin(IV) Dithiocarbamate Complexes: Chemistry and Biological Activity

Significant attention has been given to organotin(IV) dithiocabamate compounds in recent times. This is due to their ability to stabilize specific stereochemistry in their complexes, and their diverse application in agriculture, biology, catalysis and as single source precursors for tin sulfide nanoparticles. These complexes have good coordination chemistry, stability and diverse molecular structures which, thus, prompt their wide range of biological activities. Their unique stereo-electronic properties underline their relevance in the area of medicinal chemistry. Organotin(IV) dithiocabamate compounds owe their functionalities and usefulness to the individual properties of the organotin(IV) and the dithiocarbamate moieties present within the molecule. These individual properties create a synergy of action in the hybrid complex, prompting an enhanced biological activity. In this review, we discuss the chemistry of organotin(IV) dithiocarbamate complexes that accounts for their relevance in biology and medicine

SnS2 and SnO2 Nanoparticles Obtained from Organotin(IV) Dithiocarbamate Complex and Their Photocatalytic Activities on Methylene Blue

This work reports the photocatalytic degradation of methylene blue (MB) dye using SnS2 and SnO2 nanoparticles obtained from a solvothermal decomposition (in oleylamine) and pyrolysis (in a furnace) processes, respectively, of the diphenyltin(IV) p-methylphenyldithiocarbamate complex. The complex, which was used as a single-source precursor and represented as [(C6H5)2Sn(L)2] (L = p-methylphenyldithiocarbamato), was synthesized and characterized using various spectroscopic techniques and elemental analysis. The structural properties and morphology of the as-synthesized nanoparticles were studied using X-ray diffraction (XRD) technique and transmission electron microscopy (TEM). UV-visible spectroscopy was used to study the optical property. The hexagonal phase of SnS2 and tetragonal SnO2 nanoparticles were identified, which exhibited varying sizes of hexagonal platelets and rod-like morphologies, respectively. The direct band gap energies of both materials, estimated from their absorption spectra, were 2.31 and 3.79 eV for SnS2 and SnO2, respectively. The photocatalytic performances of the SnS2 and SnO2 nanoparticle, studied using methylene blue (MB) as a model dye pollutant under light irradiation, showed that SnO2 nanoparticles exhibited a degradation efficiency of 48.33% after 120 min reaction, while the SnS2 nanoparticles showed an efficiency of 62.42% after the same duration of time. The higher efficiency of SnS2 compared to the SnO2 nanoparticles may be attributed to the difference in the structural properties, morphology and nature of the material’s band gap energy

PbS Nanoparticles Prepared Using 1, 10-Phenanthroline Adduct of Lead(II) Bis(N-alkyl-N-phenyl dithiocarbamate) as Single Source Precursors

Dithiocarbamate complexes have remained prominent as single source precursors for the synthesis of clean metal sulfide nanoparticles. This study reports the synthesis of lead sulfide (PbS) nanoparticles using some novel complexes of 1, 10-phenanthroline lead(II) bis(N-alkyl-N-phenyl dithiocarbamate), represented as [Pb(L1)2phen] (1) and [Pb(L2)2phen] (2) (where L1 = bis(N-ethyl-N-phenyldithiocarbamate; L2 = bis(N-butyl-N-phenyldithiocarbamate); phen = 1, 10 phenanthroline) as a single source precursors. The complexes (1 and 2) were synthesized and characterized using various spectroscopic techniques and elemental analysis. The nanoparticles were synthesized via a solvothermal approach in oleylamine, used as a capping agent, and were given as PbS(1) and PbS(2) from [Pb(L1)2phen] (1) and [Pb(L2)2phen] (2), respectively, which were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and absorption spectroscopy. The diffraction patterns confirmed the formation of face-centered cubic phase PbS nanoparticles with a preferential growth orientation along the (200) plane. The TEM images showed that PbS(1) were of a spherical morphology, while the morphology of PbS(2) tended to produce short rods. This was due to variation in the functional group on the precursor compounds. This variation also resulted in the different band gap energies found such as 1.148 and 1.107 eV for PbS(1) and PbS(2), respectively, indicating a blue shift from the bulk

Biogenic Synthesis of CuO, ZnO, and CuO–ZnO Nanoparticles Using Leaf Extracts of Dovyalis caffra and Their Biological Properties

Biogenic metal oxide nanoparticles (NPs) have emerged as a useful tool in biology due to their biocompatibility properties with most biological systems. In this study, we report the synthesis of copper oxide (CuO), zinc oxide (ZnO) nanoparticles (NPs), and their nanocomposite (CuO–ZnO) prepared using the phytochemical extracts from the leaves of Dovyalis caffra (kei apple). The physicochemical properties of these nanomaterials were established using some characterization techniques including X-ray diffraction analysis (XRD), ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDX). The XRD result confirmed the presence of a monoclinic CuO (Tenorite), and a hexagonal ZnO (Zincite) nanoparticles phase, which were both confirmed in the CuO–ZnO composite. The electron microscopy of the CuO–ZnO, CuO, and ZnO NPs showed a mixture of nano-scale sizes and spherical/short-rod morphologies, with some agglomeration. In the constituent’s analysis (EDX), no unwanted peak was found, which showed the absence of impurities. Antioxidant properties of the nanoparticles was studied, which confirmed that CuO–ZnO nanocomposite exhibited better scavenging potential than the individual metal oxide nanoparticles (CuO, and ZnO), and ascorbic acid with respect to their minimum inhibitory concentration (IC50) values. Similarly, the in vitro anticancer studies using MCF7 breast cancer cell lines indicated a concentration-dependent profile with the CuO–ZnO nanocomposite having the best activity over the respective metal oxides, but slightly lower than the standard 5-Fluorouracil drug

Organotin(IV) complexes derived from N-ethyl-N-phenyldithiocarbamate: Synthesis, characterization and thermal studies

Organotin(IV) dithiocarbamate complexes, RSnClL2 and R2SnL2 (R = Me, Bu, Ph, and L = N-ethyl-N-phenyldithiocarbamate), have been synthesized by the reaction of mono- and disubstituted organotin(IV) with ammonium dithiocarbamate. The complexes were characterized by elemental analyses, and spectroscopic techniques (1H, 13C NMR and FTIR). The structures of Me2SnL2 and Bu2SnL2 were further established by single crystal X-ray diffraction technique. The crystal structure analysis showed that both complexes (Me2SnL2 and Bu2SnL2) exist as monomers. One of the dithiocarbamate ligands formed a chelate, while the other dithiocarbamate bonded to the central tin atom through one of the sulfur atoms and the second sulfur atom existed as a pendant to form distorted trigonal bipyramidal geometry. The thermal stability of all the complexes was studied using simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC). The TG-DSC results showed that Me2SnL2, BuSnClL2, Bu2SnL2, and PhSnClL2 displayed similar decomposition pathway via isothiocyanate intermediate, while MeSnClL2 and Ph2SnL2 showed decomposition pathways different from the rest of the complexes. All the complexes resulted in SnS as the final product of the thermal decomposition process. Keywords: Organotin, Dithiocarbamate, Crystal structure, Thermal studie

Plant Extracts Mediated Metal-Based Nanoparticles: Synthesis and Biological Applications

The vastness of metal-based nanoparticles has continued to arouse much research interest, which has led to the extensive search and discovery of new materials with varying compositions, synthetic methods, and applications. Depending on applications, many synthetic methods have been used to prepare these materials, which have found applications in different areas, including biology. However, the prominent nature of the associated toxicity and environmental concerns involved in most of these conventional methods have limited their continuous usage due to the desire for more clean, reliable, eco-friendly, and biologically appropriate approaches. Plant-mediated synthetic approaches for metal nanoparticles have emerged to circumvent the often-associated disadvantages with the conventional synthetic routes, using bioresources that act as a scaffold by effectively reducing and stabilizing these materials, whilst making them biocompatible for biological cells. This capacity by plants to intrinsically utilize their organic processes to reorganize inorganic metal ions into nanoparticles has thus led to extensive studies into this area of biochemical synthesis and analysis. In this review, we examined the use of several plant extracts as a mediating agent for the synthesis of different metal-based nanoparticles (MNPs). Furthermore, the associated biological properties, which have been suggested to emanate from the influence of the diverse metabolites found in these plants, were also reviewed

Green synthesis, antioxidant and anticancer activities of TiO2 nanoparticles using aqueous extract of Tulbhagia violacea

In this study, titanium oxide nanoparticles represented as TiO2(1), TiO2(2), and TiO2(3) were prepared using different volumes (10, 20, and 40 mL, respectively) of aqueous leaf extract of Tulbhagia violacea. The physicochemical characteristics of these materials were established using X-ray diffraction (XRD), ultraviolet–visible (UV–vis) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy. The obtained XRD pattern confirmed the formation of the anatase TiO2 phase in all the prepared materials irrespective of the volume of extracts used. Nevertheless, TiO2(2) nanoparticles obtained using 20 mL of plant extract showed the highest crystallinity. The maximum absorption wavelength found in the region between 260 and 267 nm in the UV–vis spectroscopy study suggested a quantum size effect. All synthesized TiO2 nanoparticles appeared to possess varying shapes and sizes, mostly dominated by rectangular shapes that were irregularly distributed across the materials. The material was found to be highly agglomerated due to the high calcination temperature. The antioxidant assay showed weak to moderate activity relative to the standard ascorbic acid. Also, compared to 5-Fluorouracil, all the nanoparticles exhibited moderate cytotoxicity against HEK 293 and HeLa cell lines. The TiO2 (1) showed the best specificity towards the cancer cell line with IC50 values of 29.73 and 34.27 µg/mL for both HeLa and HEK 293 cell lines, respectively. This suggests its potential as a promising candidate in applications where it is important to protect healthy cells

Synthesis, characterization, and biological evaluation of some metal complexes containing N and S donor atoms

Eight new bipyridine adducts of Zn(II) and Ni(II) dithiocarbamate complexes have been prepared from the reaction of Zn(II) and Ni(II) complexes of N-ethyl-N-phenyldithiocarbamate and 4,4′ dipyridine, 4,4′-dimethyl-2,2′-bipyridine, 4,4′-dimethoxy-2,2′-bipyridine, 4,4′-ditertbutyl-2,2′-bipyridine. The resulting adducts were represented as [M(L1)2(DP)], [M(L1)2(DMeB)], [M(L1)2(DMxB)] and [M(L1)2(DTB)] respectively (where M = Zn or Ni). The structural configuration of these adducts was established using various spectroscopic techniques. The obtained data from the spectroscopic studies revealed a change in the tetrahedral configuration of the parent complexes to octahedral coordination in the adducts due to an additional metal-nitrogen bond. The formation of this bond was established by a considerable shift in the peaks around the metal-nitrogen (M−N) coordination upon the formation of the adducts. The study of biological properties including cytotoxicity, antioxidant, and anti-inflammatory properties were carried out. No noticeable trends were reported in all the studies despite the concentration-dependent profile shown in the assays and the structural similarities of the compounds. These adducts, nevertheless, showed good antioxidant activity in the DPPH assay, with IC50 ranging between 3.78 and 4.87 µg/mL which is better than the standard ascorbic acid (4.96 µg/mL). Also, in the cytotoxicity study, the adducts [Zn(L)2DMeBp] (1) and [Ni(L)2 DTBp] (6) showed the best activity against the mutating human cervical cancer (HeLa) and embryo kidney (HEK 293) cell lines and better than the standard 5-Flurouracil. The molecular docking studies further revealed that the adducts had a good binding affinity to the drug targets used for the study