Influence of functionalities on the structure and luminescent properties of organotin(IV) dithiocarbamate complexes

Biologically potent organotin(iv) complexes of N-acetylated β-amino acids with spectroscopic, X-ray powder diffraction and molecular docking studies†

Twelve novel organotin(iv) complexes (1–12) of N-acetylated β-amino acids (L₁–L₈) were synthesized and characterized by elemental analysis, FTIR, multinuclear (¹H, ¹³C, ¹¹⁹Sn) NMR, EI-MS and powder XRD techniques. The XRD results determined lattice parameters, average particle size, and intrinsic strain and confirmed the crystalline nature of complexes as face centered cubic phases. Molecular docking analysis using a catalytic pocket of the α-glucosidase enzyme indicated that most of the compounds displayed a well-fitted orientation and occupied important amino acids in the enzyme's catalytic pocket. Furthermore, in vitro α-glucosidase inhibitory activity results revealed that L₁ and complexes 4, 6 and 10 showed the highest activity with IC₅₀ values of 21.54 ± 0.45, 37.96 ± 0.81 and 35.20 ± 1.02, respectively, compared to standard acarbose with an IC₅₀ value of 42.51 ± 0.21. In addition, in vivo antidiabetic activity of selected compounds using alloxan induced diabetic rabbits showed that L₄ and complexes 4, 6, 10, 12 showed significant activities like standard metformin. Anti-bacterial activity against the selected Gram-positive and Gram-negative bacterial strains has the following order Escherichia coli > Pseudomonas aeruginosa > Staphylococcus aureus > Bacillus subtilis. Similarly, antioxidant activity by the DPPH scavenging method was also studied with following results: triorganotin > diorganotin > ligands.

Novel organotin(iv) complexes of N-acetylated β-amino acids were synthesized and characterized by different techniques. The molecular docking, in vitro α-glucosidase inhibitory, and in vivo antidiabetic activity studies were carried out.

Syntheses, structures, in vitro cytostatic activity and antifungal activity evaluation of four diorganotin(iv) complexes based on norfloxacin and levofloxacin

Four organotin(iv) complexes have been designed and synthesized from the reactions of R2SnO (R = Me, Ph) with the corresponding ligands norfloxacin and levofloxacin. And the cytostatic and antifungal activity test have been done.

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.

Cr2S3(Et2DTC) complex and [Cr2S3-MoS2(Et2DTC)] bilayer thin films: single source stationed fabrication, compositional, optical, microstructural and electrochemical investigation

Current investigation has for the first time synthesized chromium sulphide diethyldithiocarbamate [Cr₂S₃(Et₂DTC)] complex utilizing diethyldithiocarbamate (DDTC) utilizing single source precursor method. Thin films of bilayer chromium sulphide diethyldithiocarmate and molybdenum disulphide [Cr₂S₃-MoS₂(Et₂DTC)] were deposited on the fluorine doped tin oxide (FTO) substrate by physical vapour deposition (PVD). Synthesized complex and bilayer were characterized by Xray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and scanning electron microscopy (SEM) for exploration of the compositional, optical, crystalline and morphological parameters, respectively. FT-IR peaks expressed the chelation of [Cr₂S₃(Et₂DTC)] expressing interactions between chromium sulphide and the ligand. The band gaps obtained from Tauc plot were 3.89 (direct) and 3.38 eV (indirect), respectively for Cr₂S₃(Et₂DTC) complex. The direct and indirect band gap of 3.75 and 3.35 eV, respectively, were obtained for [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films. Average crystallite size of 13 (hexagonal orientation) and 13.4 (orthorhombic orientation) nm and for Cr₂S₃(Et₂DTC) complex and [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films expressed from XRD. SEM micrographs expressed cannular and rod protrusions for Cr₂S₃-DDTC complex and smoother and unvarnished surficial characteristics for [Cr₂S₃-MoS₂(Et₂DTC)] bilayer thin films corresponding to compactness and uniformity of the films. Furthermore, [Cr₂S₃-MoS₂(Et₂DTC)] also expressed remarkable electrochemical aspects of the current generation and operational stability of analysed through 5760 s at 100 mA analysed via linear sweep voltammetry and chronoamperometry. The fabricated films can be efficiently used in optoelectronic devices. Current work can be extended to the optimization of bilayer thin films fabrication for achieving an alleviation in the band gaps.

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.

Crystal structures and Hirshfeld surface analyses of (N-hexyl-N-methyl-dithio-carbamato-κ2S,S')triphenyl-tin(IV) and [N-methyl-N-(2-phenyl-ethyl)-dithio-carbamato-κ2S,S']tri-phenyl-tin(IV)

The crystal and mol-ecular structures of two tri-phenyl-tin di-thio-carbamate compounds, viz. [Sn(C6H5)3(C8H16NS2)], (I), and [Sn(C6H5)3(C10H12NS2)], (II), are described. The di-thio-carbamate ligand in each mol-ecule coordinates in an asymmetric fashion resulting in heavily distorted tetra-hedral C3S coordin-ation geometries for the Sn atoms, with the distortions traced to the close approach of the non-coordinating thione-S atom. The mol-ecular packing in both compounds features C-H⋯π(Sn-phen-yl) inter-actions. In (I), the donors are Sn-phenyl-C-H groups leading to centrosymmetric aggregates, while in (II), the donors are both Sn-phenyl-C-H and methyl-C-H groups leading to supra-molecular chains propagating along the b axis. The identified aggregates assemble into their respective crystals with no directional inter-actions between them. An analysis of the Hirshfeld surfaces show distinctive patterns, but an overwhelming predominance (>99% in each case) of H⋯H, C⋯H/H⋯C and S⋯H/H⋯S contacts on the respective Hirshfeld surface.

Close contacts involving germanium and tin in crystal structures: experimental evidence of tetrel bonds

Modeling indicates the presence of a region of low electronic density (a "σ-hole") on group 14 elements, and this offers an explanation for the ability of these elements to act as electrophilic sites and to form attractive interactions with nucleophiles. While many papers have described theoretical investigations of interactions involving carbon and silicon, such investigations of the heavier group 14 elements are relatively scarce. The purpose of this review is to rectify, to some extent, the current lack of experimental data on interactions formed by germanium and tin with nucleophiles. A survey of crystal structures in the Cambridge Structural Database is reported. This survey reveals that close contacts between Ge or Sn and lone-pair-possessing atoms are quite common, they can be either intra- or intermolecular contacts, and they are usually oriented along the extension of the covalent bond formed by the tetrel with the most electron-withdrawing substituent. Several examples are discussed in which germanium and tin atoms bear four carbon residues or in which halogen, oxygen, sulfur, or nitrogen substituents replace one, two, or three of those carbon residues. These close contacts are assumed to be the result of attractive interactions between the involved atoms and afford experimental evidence of the ability of germanium and tin to act as electrophilic sites, namely tetrel bond (TB) donors. This ability can govern the conformations and the packing of organic derivatives in the solid state. TBs can therefore be considered a promising and robust tool for crystal engineering. Graphical abstract Intra- and intermolecular tetrel bonds involving organogermanium and -tin derivatives in crystalline solids.

Di-n-butyl-bis-[N-(2-meth-oxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S']tin(IV): crystal structure and Hirshfeld surface analysis

The complete mol-ecule of the title compound, [Sn(C4H9)2(C5H10NOS2)2], is generated by a crystallographic mirror plane, with the SnIV atom and the two inner methyl-ene C atoms of the butyl ligands lying on the mirror plane; statistical disorder is noted in the two terminal ethyl groups, which deviate from mirror symmetry. The di-thio-carbamate ligand coordinates to the metal atom in an asymmetric mode with the resulting C2S4 donor set defining a skew trapezoidal bipyramidal geometry; the n-butyl groups are disposed to lie over the longer Sn-S bonds. Supra-molecular chains aligned along the a-axis direction and sustained by methyl-ene-C-H⋯S(weakly coordinating) inter-actions feature in the mol-ecular packing. A Hirshfeld surface analysis reveals the dominance of H⋯H contacts in the crystal.

Variation of the Molecular Conformation, Shape, and Cavity Size in Dinuclear Metalla-Macrocycles Containing Hetero-Ditopic Dithiocarbamate-Carboxylate Ligands from a Homologous Series of N-Substituted Amino Acids

A homologous series of dithiocarbamate ligands derived from N-substituted amino acids was reacted with different diorganotin dichlorides to give 18 diorganotin complexes. Spectroscopic and mass spectrometric analysis evidenced the formation of assemblies with six-coordinate tin atoms embedded in skewed-trapezoidal bipyramidal coordination environments of composition C₂SnS₂O₂. Single-crystal X-ray diffraction analysis for three of the compounds revealed a one-dimensional polymeric structure for the complex with the ligand derived from 5-aminopentanoic acid, which through further intermolecular Sn···O interactions generated an overall two-dimensional coordination polymer containing 40-membered hexanuclear tin macrocycles. On the contrary, the ligands derived from 6-aminohexanoic and 8-aminooctanoic acid provided the expected 22- and 26-membered dinuclear macrocyclic structures. Density functional theory calculations for a representative series of macrocyclic complexes of composition [Me₂SnLx]₂ with Lx = ¯S₂CN(Me)-(CH₂)_x-COO¯ (x = 3-12) enabled a detailed analysis of the variations in the molecular conformation, shape, and cavity size of the macrocycles in dependence of the aliphatic spacer. Because of odd-even effects, the difunctional ligands can adopt either a curved or a twisted-pincer shape, while the SnS_xO_4-x (x = 0-4) moieties can act either as linear or angular tectons with varying connectivity angles.

Ag(i), Cu(ii), Co(iii) and Hg(ii) complexes and metal-assisted products derived from 4-methyl-piperidine-carbodithioate: syntheses, structures, thermal analyses, redox behaviour and fluorescence properties

Ag(i), Cu(ii), Co(iii) and Hg(ii) complexes and metal-assisted products derived from 4-methyl piperidine have been synthesized. The Cu(ii) complex is redox reversible and compounds3and5are fluorescent.