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• A chromone-based diorganotin(IV) crystalline solid (DOC) is synthesized. • Single crystal X-ray diffraction and spectroscopic characterization of DOC. • Investigation of adsorption of organic dyes on DOC in an aqueous system. • Investigation of kinetics, thermodynamics and modelling of the adsorption process. A glucosyl appended chromone-based diorganotin(IV) crystalline solid (DOC) is obtained from β-D-allopyranoside substituted 3-hydroxy-benzo-γ-pyrone. The combination of organotin(IV) unit, glucosyl substituent and chromone skeleton introduced some special features to the solid including controlled solubility, water stability, and plenty of interactive sites. The step-wise formation of products is supported by FT-IR spectroscopy, multinuclear NMR spectroscopy, CHN elemental analyses, mass spectrometry, scanning electron microscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction analyses. The DOC molecules led to herringbone architecture via O–H···O, C–H·····Sn, C–H···O, C–H·····π, and π⋯π interactions, where each DOC molecule possessed "skew-trapezoidal bipyramidal" geometry. Furthermore, the DOC has been found efficient adsorbent for organic dyes with a partition coefficient of 793.3 mg g−1 μM−1 for Brilliant blue. The theoretical studies justified the highest adsorption of Brilliant blue due to the small value of the HOMO-LUMO energy gap (Δ E = 0.34 eV), the high value of electrophilicity index (ω = 40.64), and the low value of chemical hardness (η = 0.17 eV). The Langmuir model and pseudo-second-order model well-described the adsorption parameters like adsorption behaviour, diffusion, and removal rates of dyes. Based on the results, the DOC is expected as a viable option for the uptake of organic dyes from an aqueous solution. Mononuclear water stable glucosyl appended diorganotin(IV) chelate, structural features, controlled solubility, thermal stability, and plenty of interactive sites for holding Brilliant Blue [Display omitted] [ABSTRACT FROM AUTHOR]

• New dimethytin(IV) complexes based on the diimine and isothiocyanate ligands. • Tracking structural phase transitions at different temperatures. • Structural characterization using (1H, 13C, 119Sn), and 2D NMR spectroscopy. • Hirshfeld surface analysis was used to analyze the intermolecular interaction. • Thermal properties of the complexes were investigated. Three diorganotin (IV) compounds with the general formula [SnMe 2 (NCS) 2 (NN)] have been synthesized and characterized using elemental analysis, IR, 1H, 13C, 119Sn , HH COSY, HSQC, and DEPT-135° NMR spectroscopy, and X-ray crystal structure determination. The complexes [SnMe 2 (NCS) 2 (Me 2 bpy)] (1), [SnMe 2 (NCS) 2 (phendione)] (2), and [SnMe 2 (NCS) 2 (4,4′-bpy)] (3) were synthesized by the reaction of SnMe 2 (NCS) 2 with corresponding diimine ligands of 5,5ꞌ-dimethyl-2,2ꞌ-bipyridine (Me 2 bpy), 1,10-phenanthroline-5,6‑dione (phendione), and 4,4′-bipyridine (4,4′-bpy), respectively. NMR data reveals that 1 – 3 persists as the hexa-coordinated dimethyltin(IV) complexes in solution. The X-ray single crystal investigation of [SnMe 2 (NCS) 2 (Me 2 bpy)] (1) exhibits structural phase transition during the cooling from RT (295 K) to LT (100 K). This transition is associated with a doubling of the asymmetric unit in the low-temperature phase (1-LT) relative to the room-temperature phase (1-RT), which results in the change of the space group (P2 1 /m in RT and P2 1 /c in LT). The 3D Hirshfeld surface analysis and 2D fingerprint maps were used for quantitative mapping and visualization of the small differences in the intermolecular interactions between both crystallographic phases. Our results show that the reaction of SnMe 2 (NCS) 2 with 4,4′-bipyridine is not dependent upon the mole ratio and reaction time and the resulting tin(IV) cations adopt the octahedral geometry which is linked by 4,4′-bipyridine into the coordination polymer while the pairs of μ -1,3-bridging thiocyanate anions further interconnected the tin atoms to form a 2D supramolecular chains. Thermal properties of the complexes reveal that they are thermally stable up to 173 °C for 1 , 183 °C for 2 , and 178 °C for 3. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Organotin (IV) derivatives of carboxylate ligand, 4-(4-methoxyanilino)-4-oxobutanoic acid, have been synthesized and characterized by FTIR, NMR, CHN analysis, mass spectrometry and X-ray crystallography. Single crystal data of four compounds (1–4) displayed a distorted trigonal bipyramidal environment around Sn with the three equatorial positions occupied by alkyl group. In compounds 1–3 , carboxylate oxygens of ligand play the role of a bridge between the adjacent tin atoms symmetrically giving a polymeric chain structure. In compound 4 , oxygen of the amide carbonyl moiety perform the same function and bridges the adjacent tin atoms [Sn O = 2.155 (3) and 2.428 (3) Å, respectively], with the three phenyl ipso -C atoms defining the trigonal plane and the axial positions occupied by O atoms [O1 Sn O3 = 177.62 (11) Å]. The τ values calculated for complexes 1–4 are 0.78, 0.77, 0.82 and 0.92, respectively, also confirm the trigonal bipyramidal geometry. The antimicrobial results of the synthesized compounds illustrate their use as a potential antimicrobial agent. The DNA interaction study performed by UV–visible spectroscopy as well as by molecular docking suggests the tested compounds interact with DNA through intercalation mode. The compounds were screened for anticancer activity performed against lung carcinoma and Vero cell lines resulting in activity that is almost equivalent to that of the standard, vincristine. The biological significance of these compounds is that there affect on the normal cell line is very small i.e., <27.1%. The compounds also exhibit good inhibition of urease enzyme. A good correlation was observed between the docking scores and biological activities of these compounds. Graphical abstract The synthesized organotin (IV) carboxylates display a wide range of attractive results including as DNA intercalator, Urease inhibitors, Anticancer agents and Antimicrobial agents. Overall there is a good correlation between the biological activities and docking studies. Image 1 Highlights • Synthesis of novel organotin (IV) carboxylates. • Spectroscopic characterizations and structural elucidation. • Interaction with SS-DNA via intercalative mode of interaction. • In vitro antibacterial, anticancer, urease inhibition and antileishmanial activity. • Molecular docking study. [ABSTRACT FROM AUTHOR]

Abstract A couple of luminescent organotin compounds derivated from ligands-ONO were obtained by multicomponent microwave assisted synthesis in short time (15 min) and good yields: ((E)-8, 8-8-diphenylbenzo[d] naphtho [1,2-h][1,3,6,2] dioxazastannonine (1) and (E)11, 13- di- tert -butyl, 8- diphenylbenzo [d] naphtho [1,2-h][1,3,6,2] dioxazastannonine (2)). Both compounds were fully characterized by NMR (1H, 13C, and 119Sn; 2D-NMR, HETCOR and COSY), UV–Vis, IR, and high-resolution mass spectrometry. The X-ray structures of two complexes demonstrate that the tin atoms adopt a bipyramidal trigonal geometry. The 119Sn NMR chemical shifts of the tin atom in the complexes are also consistent with the presence of pentacoordinate tin centers. The photophysical properties in solution and solid state, DFT, and voltammetry the two complexes have been determined. Graphical abstract Image 1 Highlights • Microwave-assisted multicomponent synthesis, spectroscopic, and X-ray characterization of organotin Schiff bases • Organotin absorb in the visible region around 474-489 nm, close to the solar emission maximum, with low quantum yields. • Organotin compounds absorb in the visible region around 600 to 619 nm in solid state, despite being still very low and lower than the solutions. • The solid state emission is higher for the phenyl substituted tin complexes studied here with respect to the butyl moieties. [ABSTRACT FROM AUTHOR]

Abstract Organotin(IV) complexes involving two different dithiocarbamate groups: N -methyl- N -phenyldithiocarbamate (L1) and N -ethyl- N -phenyldithiocarbamate (L2) are reported. The complexes have been characterized using spectroscopic techniques and elemental analysis, and were represented as [(CH 3) 2 Sn 2 L1L2] (1) , [(C 4 H 9) 2 Sn 2 L1L2] (2) and [(C 6 H 5) 2 SnL1L2] (3). The crystal structures of [(CH 3) 2 Sn 2 L1L2] (1) and [(C 4 H 9) 2 Sn 2 L1L2] (2) are also reported. The structure indicated that both ligands bonded to the Sn atom by displacing the chloride ions from the organotin moiety. Complex (1) gave trigonal bypyramidal geometry; while a distorted skew trapezoidal-bipyramidal geometry occurred in complex (2). Thermal studies of the complexes by TG/DTG analysis showed that the stability of the complexes was influenced by the bond length/strengths of the tin-sulfur bonds. Although, no similarity in their decomposition pathways, all the complexes yielded tin sulfides as final residues. The complexes were screened for cytotoxic activity against HeLa cells and compared to the standard drug, 5-Fluorouracil (5FU). The result obtained showed that the complexes displayed better cyto-selectivity against the HeLa cell compared to the standard drug. Complex 1 gave the best IC 50 values compared to the rest of the complexes. The cytotoxic action displayed by the complexes showed their potential as anticancer agents. Graphical abstract Image 1 Highlights • Mixed ligand complexes of organotin(IV) were synthesized and characterized. • The crystal structures of two of the complexes were reported. • Both five and six coordinate geometries were observed in the complexes. • Cytotoxic studies of the complexes showed they have better activity than 5-Fluorouracil. [ABSTRACT FROM AUTHOR]

Abstract New tri- and diorganotin (IV) derivatives of 2,4-dichlorophenoxyacetic acid with general formula: R 3 SnL and R 2 SnL 2 : {Me 3 SnL (1), Bu 3 SnL (2), Me 2 SnL 2 (3), Bu 2 SnL 2 (4) and Oct 2 SnL 2 (5), L = 2,4-dichlorophenoxyacetate} have been synthesized and characterized in solid state by elemental and FT-IR analysis, whereas in solution state by 1H and 13C NMR spectroscopy. Compound 1 was also characterized by single crystal X-ray crystallography. The FT-IR data of compounds 1 – 5 confirm the bidentate binding mode of ligand with penta and hexa-coordinated arrangements around the Sn(IV) centre in solid state. The value of C Sn C angle for complexes 1 and 3 calculated from NMR (1H and 13C) data using Lockart's equation were 114.7° and 114.9°, respectively which falls in the range of 5-coordinated geometry. The DNA binding of synthesized compounds were studied via UV–Vis spectroscopy and viscometry resulting in an intercalative mode of interaction. Molecular docking analysis of the studied compounds also supports the results of the UV–vis and viscometry. Moreover, interaction of the synthesized compounds with a cationic surfactant i.e., cetyltrimethyl ammonium bromide (CTAB) has been studied by conductometric method. Enzyme inhibition activity against α-amylase and α-glucosidase was carried out and compound 3 was found to possess maximum inhibition (88.1% and 91.3%, respectively). The theoretical study also enforce the experimental data for enzyme inhibition of the compound 3 (docking score = −12.4096) by forming seven hydrogen bonds and two pi-H linkages with the Glu 276, Ala 278, Phe 300, Arg 312, Tyr 313, Asp 349, Asn 412, Phe 430 and Arg 439 residues of the binding pocket of the α-glucosidase. The potency of the compound 3 might be due to the presence of the strong electron withdrawing chloro group. IC 50 value of the brine shrimp activity revealed that triorganotin (IV) derivatives (1 and 2) were more toxic than their diorganotin (IV) analogues. Moreover, compound 2 has the MIC values of 12.5 μg/mL and 6.25 μg/mL against S. Aureus and M. Leuteus bacterial strains, respectively. Graphical abstract The novel organotin (IV) Carboxylates complexes interact with DNA via intercalative mode. Also they have strong tendency to interact with CTAB (surfactant) as indicated by higher CMC values and the resulting in micelle formation plays an important role in drug devilry. They show strong inhibitory potential against α -amylase and α -glucosidase. The DNA interaction and enzyme inhibition by Molecular Docking strongly support the experimental data. Highlights • Synthesis of Novel organotin (IV) Carboxylates. • Spectroscopic characterizations by FT-IR, NMR and single crystal X-ray. • Interaction with SS-DNA showing intercalation confirmed by UV-vis Spectroscopy and Molecular docking study. • Interaction with CTAB (surfactant). • Inhibition of alpha amylase and alpha glucosidase enzymes. [ABSTRACT FROM AUTHOR]

Abstract Herein we describe the syntheses of 4-(2-nitrophenylsulfonamido)benzoic acid (HL), and its tri-n-butyltin(IV) complex, Bu 3 SnL. The compounds were characterized by elemental analyses, FT-IR, 1H NMR, 13C{1H} NMR and X-ray diffraction. For the complex 119Sn{1H} NMR and 119Sn Mössbauer spectroscopies were also employed. The Bu 3 SnL is a monomer in the solid and solution states but exists as a polymer in the crystalline structure. The complex adopted distinct geometries, being tetrahedral in solution and intermediate between tetrahedral and trigonal bipyramidal in the solid state. Crystal structure determination of Bu 3 SnL revealed a bipyramid-trigonal geometry around the metal center, and the presence of a polymeric structure sustained by carboxylate bridges. Interconnections in the crystal structures were analyzed using Hirshfeld surfaces. The 2D-fingerprint plots indicated that the O H/H O interactions are more frequent in the HL·H 2 O crystal packing (44.9%) than in the Bu 3 SnL (26.8%). Graphical abstract Image 1 Highlights • Bu 3 SnL is a monomer in the solid and solution states. • Bu 3 SnL is a 1D-polymer sustained by carboxylate bridges in the crystalline structure. • Contributions of O⋯H/H⋯O interactions are higher for HL⋅H 2 O than for Bu 3 SnL. [ABSTRACT FROM AUTHOR]

Six new diorganotin N -[(5-chloro-2-oxyphenyl)methylene]valinates, R 2 SnL (R = Me, 1 ; Et, 2 ; L = 5-Cl-2-OC 6 H 3 CH = NCH( i -Pr)COO: ( S )-, a ; ( R )-, b ; ( RS )-, c ), have been synthesized from the reaction of R 2 SnCl 2 with the chiral ligand KHL (potassium salt of HL) in different solvents and characterized by elemental analysis, IR, NMR ( 1 H, 13 C and 119 Sn) spectra. In benzene, the configuration of the chiral ligand was retained. ( S )-Enantiomers ( 1a and 2a ) and ( R )-enantiomers ( 1b and 2b ) display discrete molecular structures with distorted trigonal bipyramidal geometries in which two C atoms of organic groups (R) and the imino N atom occupy the equatorial positions and a phenoxide O and an unidentate carboxylate group O atom are in the axial orientation. In the methanol, the chiral ligand was racemized. 1c⋅ MeOH is a centrosymmetric dimers formed by ( R )- and ( S )- enantiomers through two Sn O⋅⋅⋅Sn bridges. The coordination geometry of the Sn atom can be described as a distorted pentagonal bipyramid with two methyl groups in axial positions. The crystal of 2c is composed of two threefold symmetric trimers, a [Et 2 SnL - ( R )] 3 and a [Et 2 SnL-( S )] 3 , with a macrocyclic 12-membered ring structure formed by the bidenate bridging coordination of carboxylate group to tin atoms. Each tin atom is six-coordinated in distorted [SnC 2 NO 3 ] octahedron geometry. The fluorescence properties of ligand KHL and complexes 1 ( 1a - 1c ) and 2 ( 2a - 2c ) have been measured. The results show the complexes may be explored for potential luminescent materials. [ABSTRACT FROM AUTHOR]

Schiff base organotin(IV) complexes C1 ∼ C5b have been synthesized via the reaction of the substituted salicylaldehyde- o -aminophenol Schiff base ligands ( L1 ∼ L3 ) with the dibenzyltin dichloride, n -butyltin trichloride or dibutyltin oxide, respectively. The complexes have been characterized by IR, UV–Vis, 1 H NMR, 13 C NMR spectra, elemental analysis and the crystal structures have been determined by X-ray diffraction. The anticancer activity of the Schiff base ligand and complexes C1 ∼ C5b against five species of cancer cell which are Hela, MCF7, HepG2, Colo205, NCI H460 were tested respectively, the tests showed that C1 ∼ C5b exhibited significant anticancer activity for the cancer cells in comparison with the ligand, and the activity was greater than carboplatin. [ABSTRACT FROM AUTHOR]

Organotin carboxylates based on an amide carboxylic acid 2-(1,3-dioxo-1 H -benzo[de]isoquinolin-2(3 H )-yl)acetic acid (HL): [(Bn 2 Sn) 2 O 2 L] 2 ·2C 6 H 6 ( 1 ) (Bn = benzyl group) and (Ph 2 Sn)(L) 2 ( 2 ) were synthesized and characterized by elemental analysis, IR, 1 H, 13 C, 119 Sn NMR spectroscopy and X-ray crystallography diffraction analysis. Complex 1 is dimeric carboxylate tetraorganodistannoxane and show a “ladder-like” molecular structure. Complex 2 is a dialkyltin carboxylate monomer possessing crystallographically imposed two-fold symmetry. Ligand in 1 and 2 adopts unidentate and bidentate coordination respectively. Both 1 and 2 form 1D, 2D and 3D supramolecular organizations in the solid state mediated through C H⋯O and π⋯π interactions which are discussed in detail. The luminescent properties and preliminary antitumor activities about this series of complexes were also studied. [ABSTRACT FROM AUTHOR]

Three new chlorodiorganotin(IV) methylferrocenyl dithiocarbamate complexes viz. [(FcCH 2 )(CH 2 CH 2 OH)NCS 2 SnMe 2 (Cl)] ( 1 ), [(FcCH 2 )(CH 2 CH 2 OH)NCS 2 Sn n Bu 2 (Cl)] ( 2 ) and [(FcCH 2 )(CH 2 CH 2 OH)NCS 2 SnPh 2 (Cl)] ( 3 ) have been synthesized and characterized by elemental analysis, IR, UV-Vis, 1 H, 13 C and 119 Sn NMR spectroscopy and X-ray crystallography. The crystal structure of 1 indicates that the coordination geometries around the tin(IV) center is intermediate between ideal trigonal-bipyramidal and square pyramidal coordination polyhedra bonded through two sulfur atoms of the dithiocarbamate ligand in an isobidentate mode, two CH 3 groups and one chlorine atom. Since, in 2 and 3 only alkyl and aryl fragments have been changed we infer that both 2 and 3 would also have the same behaviors in the solution state as observed in 1 . Ionic interactions abilities of 1 – 3 are examined in acetonitrile through UV-vis absorption spectroscopy which offers reasonably good selectivity and sensitivity towards the detection of the acetate ion. Compounds 1–3 exhibit a bathochromic shift with the acetate ion with a moderate association constant. [ABSTRACT FROM AUTHOR]

Three organotin carboxylates based on amide carboxylic acids: (Ph 3 Sn) 2 (L 1 ) ( 1 ) (L 1 = 3,3′-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f]isoindole-2,6(1 H ,3 H )-diyl)dipropionic acid), (Ph 3 Sn) 2 (L 2 )·C 7 H 8 ( 2 ) (L 2 = 3,3′-(1,3,6,8-tetraoxo-1,3,6,8-tetrahydrobenzo [ lmn ][3,8]phenanthroline-2,7-diyl)dipropionic acid), [(Ph 3 Sn)(CH 3 CH 2 O)] 2 (L 3 ) ( 3 ) (L 3 = 2,2′-(1,3,5,7-tetraoxo-5,7-dihydropyrrolo[3,4-f]isoindole-2,6(1 H ,3 H )-diyl) dibenzoic acid) were synthesized and characterized by elemental analysis, IR, 1 H, 13 C, 119 Sn NMR spectroscopy and X-ray crystallography diffraction analyses. Complexes 1–3 are di-nuclear triphenlytin carboxylates owning “S” shaped monomer structures. Ligands in 1 – 3 adopt unidentate coordination. Intermolecular hydrogen bonds and Sn···O interactions help complexes 1–3 build their supramolecular structures which are discussed in detail. The preliminary antitumor activities of 1 – 3 against HepG2 cell lines have also been studied. [ABSTRACT FROM AUTHOR]

Diorganotin(IV) complexes appended with free carboxylic acids were synthesized by reacting diorganotin(IV) dichlorides [R 2 SnCl 2 ; R = Me ( 1 ), Bu ( 2 ) and Ph ( 3 )] with an azo-imino carboxylic acid ligand i.e . 2-{4-hydroxy-3-[(2-hydroxyphenylimino)methyl]phenylazo}benzoic acid in presence of triethylamine. The complexes were characterized by elemental analysis, IR and multinuclear NMR ( 1 H, 13 C and 119 Sn) spectroscopy. The structure of 1 in solid state has been determined by X-ray crystallography. Crystal structure of 1 reveals that the compound crystallizes in monoclinic space group P 2 1 /c and is a dimeric dimethyltin(IV) complex appended with free carboxylic acid groups. In the structure of 1 , the Sn(IV) atoms are hexacoordinated and have a distorted octahedral coordination geometry in which two phenoxy oxygen atoms and the azomethine nitrogen atom of the ligand coordinate to each tin atom. One of the phenoxy oxygen atom bridges the two tin centers resulting in a planar Sn 2 O 2 core. Topological analysis is used for the description of molecular packing in 1 . Tin NMR spectroscopy study indicates that the complexes have five coordinate geometry around tin atom in solution state. Since the complexes have free carboxylic acids, these compounds could be further used as potential metallo-ligands for the synthesis of other complexes. The synthesized diorganotin(IV) complexes were also screened for their antimicrobial activities and compound 2 showed effective antimicrobial activities. [ABSTRACT FROM AUTHOR]

The syntheses and characterization of six new triorganotin(IV) complexes, Ph 3 Sn(PrACDA) ( 1 ), Bu 3 Sn(PrACDA) ( 2 ), Ph 3 Sn(BzACDA) ( 3 ), Bu 3 Sn(BzACDA) ( 4 ), Me 3 Sn(BzACDA) ( 5 ) and Cy 3 Sn(BzACDA) ( 6 ) (ACDA = 2-amino-1-cyclopentene-1-carbodithioate anion) are reported. Compounds 1 – 6 were synthesized by the reaction between the sodium salts of 2- N -propyl- or 2- N -benzyl-2-amino-1-cyclopentene-1-carbodithioate and R 3 SnCl (R = Ph, Bu, Me, Cy) in a 1:1 M ratio. The complexes were characterized by elemental analyses, IR and NMR ( 1 H, 13 C and 119 Sn) spectroscopy and by FAB + mass spectrometry. The experimental data reveal that the tin atom is coordinated to the ligand by means of the two sulfur atoms from the carbodithioate group in an anisobidentate mode, while the 119 Sn{ 1 H} NMR spectra suggest a pentacoordinate metal center in 1 – 4 and a tetracoordinate tin atom for 5 and 6 . The molecular structures of complexes 1 , 3 and 5 were confirmed by single crystal X-ray diffraction analysis showing the presence of N–H···S hydrogen bonding and a distorted trigonal bipyramid geometry for the tin atoms. [ABSTRACT FROM AUTHOR]

The reactions of triorganotin chlorides and sodium valproate, Na(OVp), yielded three triorganotin valproates [{SnMe 3 (OVp)} n ] (1) , [{SnBu 3 (OVp)} n ] (2) and [SnPh 3 (OVp)] (3) . All complexes have been authenticated in terms of infrared, 1 H and 13 C NMR, and solution- and solid-state 119 Sn NMR, 119 Sn Mössbauer and X-ray crystallography. The 119 Sn NMR experiments provided important informations concerning the structures of (1) – (3) in solution and in the solid state. The X-ray experiments revealed the double-polymeric chain of complex (1) , in which the geometry at the Sn(IV) is trigonal bipyramidal with intermolecular valproate bridges. The structure of complex (3) was re-determined and the new data show the tin cation at the centre of a distorted trigonal bipyramid, and not coordinated by four electron donating groups. The biological activity of all derivatives has been screened in terms of IC 50 (μmol L −1 ) against C. albicans (ATCC 18804), C. tropicalis (ATCC 750), C. glabrata (ATCC 90030), C. parapsilosis (ATCC 22019), C. lusitaniae (CBS 6936) and C. dubliniensis (clinical isolate 28). Complex (3) exhibited the best biocide activity. [ABSTRACT FROM AUTHOR]

Two new organotin(IV) complexes of the type R 3 SnL, where (L = p -bromo- N -methylbenzylaminedithiocarbamate and p -fluoro- N -methylbenzylaminedithiocarbamate, and R = phenyl) have been synthesized in 1:1 molar ratio with good yields and isolated as crystalline solids. The newly synthesized compounds gave fairly sharp melting points indicating that the compounds were pure. A systematic investigation of the derivatives were carried out both in solid and in solution and were suitably characterized by elemental analysis, FT-IR, 1 H, 13 C, 119 Sn NMR spectroscopies. The dithiocarbamate ligands chelated to the tin metal monodentately using only one sulfur atom showing a pair of bands due to ν(C S) below 1000 cm −1 . This phenomenon was supported by the occurrence of new medium to weak absorptions in the region 411–545, in the spectra of complexes, assigned to ν(Sn S) and ν(Sn C). The crystal structures of the two triorganotin(IV) complexes have been determined by X-ray crystallography. Both the complexes crystallized in the monoclinic, P 2(1)/ n space group. The spectral investigations and single crystal X-ray diffraction data illustrate that the two dithiocarbamato ligands in the triphenyltin(IV) derivatives 1 and 2 are monodentate and the geometry at tin is best described as a distorted tetrahedron. The in vitro antiproliferative tests of these two derivatives on three human cell lines, leukemic lymphoblastoma Jurkat cells, lymphoblastoma K-562 cells, hepatoblastoma HepG2 cells and one mouse fibroblast cells L929 show dose-dependent decrease of cell proliferation in all cell lines. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis and X-ray structural characterization of trans-dichloro-trans-bis(dimethylsulfoxide)-trans-dimethyl-tin(IV). [•] Organotin interaction with DNA at 95°C and low cytotoxicity. [•] The crystal structure has a polymeric arrangement with eight-membered rings as a result of intermolecular coordination S O→Sn. [ABSTRACT FROM AUTHOR]

Highlights: [•] Charge density in monochelate complexes containing Si, Ge and Sn atoms was analyzed. [•] The energies of O→M, M–Cl and M–C (M=Si, Ge, Sn) bonds were estimated. [•] Coordinate O→Sn and Sn–Cl bonds have mostly ionic nature. [•] The energy of the O→M bond increases along with the atomic number of the M atom. [•] The charge of the O atom correlates with the energy of a O→M bond. [ABSTRACT FROM AUTHOR]

Abstract: Three organotin(IV) complexes, Ph2Sn(mstsc) (1), Me2Sn(mstsc) (2) and Bu2Sn(mstsc) (3), have been synthesized from reaction of R2SnCl2 (R=Ph, Me and Bu) with 3-methoxysalicylaldehyde thiosemicarbazone (H2mstsc). The synthesized complexes have been characterized by elemental analysis and FT-IR, 1H, 13C and 119Sn NMR spectroscopy. The structures of 2 and 3 have been also confirmed by X-ray crystallography. On the basis of spectral and structural data thiosemicarbazone acts as a tridentate dianionic ligand and coordinates to tin through phenolic oxygen, the azomethine nitrogen and thiolate sulfur atoms. The metal coordination geometry for 2 and 3 is described as distorted square pyramid and the crystal lattices are stabilized by intermolecular hydrogen bands. On the basis of 119Sn NMR data, coordination number of tin retains five in solution. The in vitro antibacterial activity of ligand and its complexes has been evaluated against one Gram-positive and three Gram-negative bacteria. Complex 2 exhibited good activity along with the standard antibacterial drugs. The in vitro cytotoxicities of the synthesized compounds against Jurkat cells were evaluated by the standard WST-1 assay. The activity decreases in the order 3 > 1 > 2 =H2mstsc. [Copyright &y& Elsevier]

Abstract: Reactions of mono-, di-, tri-alkyltin chlorides or oxide with 5-bromopyridine-2-carboxylic acid result in five new organotin(IV) compounds, [MeSn(O2CC5NH3Br)Cl2(H2O)]·(C2H5)2O (1), [(n-Bu)Sn(O2CC5NH3Br)Cl2(H2O)]·(C2H5)2O (2), {[(n-Bu)2Sn(O2CC5NH3Br)]2O}2 (3) [(n-Bu)3Sn(O2CC5NH3Br)] n (4) and [Ph3Sn(O2CC5NH3Br)] n (5), which have been characterized by single crystal X-ray diffraction, element analysis, IR, 1H, 13C and 119Sn NMR. Three different coordination modes for the ligand are demonstrated in this group of compounds: (1) bidentate mode with the pyridyl nitrogen atom and carboxyl oxygen atom for mono-alkyltin compounds 1 and 2, in which six-coordinated tin center is also bound with two chlorine ions and one water molecule; (2) compound 3 is a tetranuclear centrosymmetric dimer with a central Sn2O2 four-membered ring. The four tin atoms are linked by two bridging carboxyl groups while the remaining two act as monodentate ligands to the endo- and exo-cyclic tin atoms; (3) for tri-alkyltin compounds 4 and 5, the bidentate bridging carboxylic group coordinates with two different tin atoms through the Snh name="sbnd" />Csp="0.25" />→Sn bond, and the carboxylate bridge propagates 1D polymeric chains, typical for five coordinate tin. However, in compounds 3–5, the pyridyl nitrogen atoms do not participate in the coordination. For triorganotin(IV) polymers 4 and 5, the solution studies show the collapse of the intermolecular interactions observed in the solid state to yield monomeric species. [Copyright &y& Elsevier]

Abstract: New hybrid organic–inorganic compound, bis(1,4-H2-1,2,4-triazolium) hexachloridostannate(IV) monohydrate, [(1,4H2t)2SnCl6]⋅H2O crystallizes in P21/c space group. Weak hydrogen bonds exist in the structure. The route of protonation of the 1,2,4-triazole and tautomer equilibrium constants for the cationic forms were theoretically studied by means of B3LYP/6-31G* method. The 1,4H2t+ cation turned out to be the most stable form of mono-protonated species. Calculated IR and Raman spectra for 1,4H2t+ cation (gas phase) are in very good agreement with the experimental data. Infrared and Raman bands were assigned on the basis of PED analysis. [Copyright &y& Elsevier]

Abstract: New organotin(IV) complexes, Ph2SnL (1) and Me2SnL (2), have been synthesized from reaction of corresponding diorganotin(IV) dichlorides with a Schiff base, 3-(2-hydroxy-5-methylphenylamino)-1,3-diphenylprop-2-en-1-one (H2L), derived from condensation of 2-amino-4-methylphenol with dibenzoylmethane. The synthesized compounds have been investigated by elemental analysis and IR, 1H NMR, and 119Sn NMR spectroscopy. Spectroscopic studies show that the Schiff base acts as a tridentate dianionic ligand and coordinates via the nitrogen and phenolic and enolic oxygen atoms. The structures of H2L and 2 have been also confirmed by X-ray crystallography. Schiff base exists as the keto-amine tautomeric form in solid state with two intramolecular hydrogen bonds of the NO type and also intermolecular hydrogen bonds of OO type that create a dimer. In the structure of 2, tin center is surrounded by two O and one N atoms from the ligand and two C atoms of methyl groups and the sixth coordination site is occupied by phenolic oxygen atom of another molecule, thus a dimeric molecule with a Sn2O2 four-membered ring is formed. The in vitro antibacterial activity of ligand and complexes has been evaluated against Gram-positive (Bacillus cereus and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. H2L showed no activity but the diphenyltin(IV) complex exhibited good activities along with the standard antibacterial drugs. [Copyright &y& Elsevier]

Abstract: Phosphoryl donor (PO) ligands (tBuNH)3PO (1), (C6H5CH2NH)3PO (2) and (4-NO2–C6H4C(O)NH)(OC4H8N)2PO (3) were used for the preparation of new organotin(IV) complexes Cl2Me2Sn(PO)2 (4–6). The environment at the nitrogen atom in the phosphoramide ligand is almost planar and it does not take part in hydrogen bonding as an acceptor in complexes 4–6, reflecting its low Lewis base character, and the Sn atom is located at the inversion center, making half of the molecule related by symmetry. The Sn coordination geometry is octahedral with the pair of similar ligands in a trans orientation. The crystal structure of 6 demonstrates that the phosphoryl group, and not the carbonyl group, coordinates to the tin center. A blue shift in the Ning frequencies of 4 and 6, in comparison to the free ligands 1 and 3, is attributed to vanish of the NO hydrogen bonds, but the Ping frequencies of the complexes exhibit no significant changes with respect to the related ligands because of minor differences caused by forming the PSn instead of the PHR experiments indicate an increasing in 2 J(P,H) coupling constants in 4 and 6 and 3 J(P,C) in 5 compared to the related ligands. The hydrogen bond pattern of the ligands and the complexes were compared. [Copyright &y& Elsevier]

Abstract: Two organotin(IV) carboxylates of (E)-3-(2-nitrophenyl) propenoic acid (HL), [Ph3SnL] n (1) and {[Bu2SnL]2O}2 (2), have been synthesized. All the complexes were characterized by elemental analysis, FT-IR and NMR (1H, 13C) spectroscopy. In addition, the molecular structures of 1 and 2 have been determined by single crystal X-ray diffraction analysis. Complex 1 consisted of a 1D chain polymer and was interconnected by Cπ stacking to aggregate in 2D framework. Complex 2 contained a dimeric tetraorganodistannoxane of ladder arrangement and was linked by CO hydrogen bonds to form a 1D chain. Their antitumor activities were also investigated. [Copyright &y& Elsevier]

Abstract: The synthesis and characterization of three organotin(IV) compounds with phenylglyoxylic acid isonicotinyl hydrazone (L) are reported. These compounds with the Schiff base ligand of the type – [R 2SnL x Y y ] z (x = y =1, z =2: R 1 =CH3, Y1 =EtOH for compound 1 or R 2 =C6H5, Y2 =H2O for compound 2; and x =2, y =0, z =1, R = n-C4H9 for compound 3) are characterized by IR, 1H, 13C NMR and elemental analysis. The crystal structures of the Schiff base ligand and the corresponding compounds have been determined by X-ray diffraction. In compounds 1 and 2, the tin atom is seven-coordinate in a distorted pentagonal bipyramid geometry chelating by the Schiff base ligand in an enolic tridentate fashion, forming a Sn2O2 ring, only with different coordinated solvent, water for 2 and ethanol for 1. However, in compound 3, there exists two different coordinate modes for the same ligand, one type of the usual enolic tridentate and the other type of unique carboxylate monodentate coordination without the participation of the amide group, this results in the central tin atom presenting six-coordinate in a distorted octahedron geometry. Fascinatingly, the supramolecular infrastructures were observed in the Schiff base ligand and three compounds, which exist either as two-dimensional sheets or as three-dimensional networks assembled from the organometallic subunits through intermolecular OX or CX (Xydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract: Based on 5-hydroxyisophthalic acid (H2HIPA), two cyclooligomeric organotin carboxylates [nBu2Sn(HIPA)]3·3(H2O) (1) and [(Me3Sn)2(HIPA)]4 (2) have been synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis, IR, 1H and 119Sn NMR spectra. Di-n-butyltin(IV) compound 1 presents a cyclotrimeric structure containing a 24-membered macrocyclic cavity. All atoms of the macrocycle are almost coplanar and six oxygen atoms direct into the interior and six Sn–butyl groups are approximately perpendicular to the cyclotrimeric plane. The diameter of the cyclic cavity is large enough for the introduction of n-butyl groups. Thus two molecules form a bis[2]pseudorotaxane through mutual threading via two of the Sn–butyl groups. Compound 2 is a weakly-bridged cyclotetramer owing to the presence of bidentate bridging carboxylate ligands. X-ray crystallographical analysis reveals that there are two types of coordination modes for carboxylic groups in compound 2: monodentate and bidentate. The geometries of all tin atoms in 2 can also be classified into two types: pentacoordinated endocyclic tin and tetracoordinated exocyclic tin. In compound 2, each endocylic tin atom exhibits two different Snand further solution studies show collapse of the intermolecular weak Sntions observed in the solid state to yield monomeric species. Interestingly, the intermolecular hydrogen bonds have resulted in the formation of 2D network structures for the titled compounds. Additionally, an intriguing 2D network bilayer has been observed for 1. [ABSTRACT FROM AUTHOR]

Abstract: Four new diorganotin(IV) complexes have been prepared from R2SnCl2 (R=Me, Ph) with the ligands 5-hydroxy-3-metyl-5-phenyl-1-(S-benzildithiocarbazate)-pyrazoline (H2L1) and 5-hydroxy-3-methyl-5-phenyl-1-(2-thiophenecarboxylic)-pyrazoline (H2L2). The complexes were characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR and Mössbauer spectroscopies. The complexes [Me2SnL1], [Ph2SnL1] and [Me2SnL2] were also studied by single crystal X-ray diffraction and the results showed that the Sn(IV) central atom of the complexes adopts a distorted trigonal bipyramidal (TBP) geometry with the N atom of the ONX-tridentate (X=O and S) ligand and two organic groups occupying equatorial sites. The C–Sn–C angles for [Me2Sn(L1)] and [Ph2Sn(L1)] were calculated using a correlation between 119Sn Mössbauer and X-ray crystallographic data based on the point-charge model. Theoretical calculations were performed with the B3LYP density functional employing 3–21G(*) and DZVP all electron basis sets showing good agreement with experimental findings. General and Sn(IV) specific IR harmonic frequency scale factors for both basis sets were obtained from comparison with selected experimental frequencies. [ABSTRACT FROM AUTHOR]

Abstract: A mononuclear precursor complex, [(CH3)2Sn(tpdtc)] and several of its heterobimetallic derivatives of the type, [(CH3)2Sn(tpdtc)]MCl2 have been synthesized by the simple addition reaction of transition metal chlorides, MCl2·nH2O where tpdtc=tetraethylenepentamine bis(dithiocarbamate) anion, M=Fe(II), Co(II), Ni(II), Cu(II) and Zn(II). The synthesized complexes have been systematically characterized by the physicochemical and spectroscopic techniques. A square-pyramidal geometry has been proposed for all the transition metal atoms with chloride ions occupying the axial while the three nitrogen atoms occupying the equatorial positions. A symmetrical bidentate coordination has been observed for the dithiocarbamato moiety leading to the formation of 18 member cavity. The thermal studies reveal that the mononuclear complex decomposes in three stages while its heterobimetallic analog exhibits a simple two-stage profile. The conductivity measurement data (1mmol solution) implies a non-electrolytic behavior for all the complexes as evident by their low conductivity values obtained at room temperature. The heterobimetallic complexes have also been tested against the bacterial (Escherichia coli and Pseudomonas aeruginosa) and antifungal strains (Aspergillus niger and Fusarium oxysporum). All the complexes were found to be active against the test organisms and maximum activity was found for [(CH3)2Sn(tpdtc)]CuCl2 complex. [Copyright &y& Elsevier]

Abstract: Dimethyltin bis(thioacetate) has been prepared by a reaction of dimethyltin dichloride. Attempts to prepare anionic complexes were not successful. The reactions have been explained on the basis of DFT calculations. The compound has been characterized by multinuclear NMR and IR spectral studies. X-ray study revealed that the molecular structure resembled the transition state of the trans–cis pathway of a skew trapezoid. Absorption and emission spectra of the compound have also been studied. [Copyright &y& Elsevier]

Abstract: This paper describes the synthesis of discrete free-standing porphyrin nanoparticles using a reprecipitation method, which is an approach widely used in the synthesis of organic nanoparticles. The crystallization of tin(IV) porphyrin is investigated thoroughly by changing the concentration of aqueous solution for the first time. The morphology is then probed using transmission electron microscopy and atomic force microscopy. It is found that the morphology of the porphyrin nanoparticles changed dramatically in this process. The initial characterization of the porphyrin nanoparticles is analyzed using dynamic light scattering. Further analyses of their aggregation modes are conducted by spectroscopic methods such as ultraviolet–visible (UV–vis) absorption, fluorescence spectra and X-ray diffraction (XRD). Their UV–vis spectra characteristics are discussed in detail. On the basis of the findings, the influence of these peripheral substituents on the sol formation and the aggregation mode is discussed. [Copyright &y& Elsevier]

Abstract: In this paper, we have reported adduct complex structure of triphenyltin(IV) chloride and pyridine-2-ethanol as a novel triorganotin complex, which was prepared by the reaction of Ph3SnCl with pyridine-2-ethanol. The complex was characterized by elemental analysis, mass spectrometry, and IR, 1H, 13C and 119Sn NMR spectroscopies. The molecular structure was determined by single crystal X-ray analysis. Complex adapts trigonal–bipyramidal geometry with trigonality index τ =0.88; the phenyl substituents on tin occupying the equatorial positions and the oxygen and chlorine atoms taking up the axial positions. DFT calculations of adduct complex compound of triphenyltin(IV) chloride and pyridine-2-ethanol ligand as a monomeric and dimeric forms at the B3LYP/6-31G (d, p) level using effective core potential with consideration of relativistic effects for stannous have been performed. Theoretical investigation of dimeric form of complex, which exists in the crystal structure, shows the stabilization role of intermolecular hydrogen bonding in this system. [Copyright &y& Elsevier]

Abstract: Tetramethyl tin reacts with dodecatungstosilicic acid H4SiW12O40 in anhydrous DMSO with evolution of methane to yield the trimethyl tin salt of the heteropolyoxometalate [α-SiW12O40][(CH3)3Sn(DMSO)2]4 ·2DMSO. The structure has been determined by X-ray diffraction and shows that there is no direct bond between the polyoxometalate and the tin complex. 119Sn NMR indicates that tin has quite the same coordination in the solid state and in DMSO solution. [Copyright &y& Elsevier]

Abstract: The MeO2CCH2CH2 ligand in X3SnCH2CH2CO2Me, (X=Cl, Br or I), acts as a C,O-chelating group, via the carbonyl group, both in the solid state and in solutions in non-coordinating solvents. The crystal structures of 1 (X=Cl), a redetermination at 120K and of I (X=Br), at 298 and 120K, are reported. Comparison of the intramolecular Snngths in solid 1 (X=Cl, Br or I) indicates that the strength of the Sntion increases in the order X=I

Abstract: Three new organotin(IV) complexes with 4-methyl-5-trifluoromethyl-4H-1,2,4-triazolin-3(2H)-thione {Me3Sn[N(C4H4F3N2S)]} n (1), Ph3Sn[S(C4H4F3N2)] (2), and {n-Bu2Sn[N(C4H4F3N2S)](μ-OH)}2 (3) have been synthesized and characterized by elemental, IR, 1H, 13C, and 119Sn NMR analyses and X-ray crystallography. The central tin atoms of complexes 1–3 are all five-coordinated with distorted trigonal bipyramidal geometries. Interestingly, 1 shows an infinite helical polymeric chain structure via intermolecular Sn←S interactions, however, 2 and 3 show dimeric and Sn2O2 unit structures, respectively. [Copyright &y& Elsevier]

(Z)-1-[2-(tri-o-tolylstannyl)vinyl]-1-cyclohexanol (1) was synthesized by the additive reaction of 1-Ethynylcyclohexanol with tri-o-tolyltin hydride. One or two of the o-tolyl groups of compound (1) was substituted by Cl, Br, I to yield derivatives of the type [n=1, X=Cl (2), Br (3), I (4); n=2, X=Br (5)]. The compounds (1–5) were characterized by elemental analysis, 1H NMR and FT-IR Spectroscopy. The crystal structures of (1) and (4) have been determined by single crystal X-ray diffraction analysis. The Sn atom in (1) exhibits tetrahedral geometry distorted towards trigonal bipyramid due to a weak intramolecular interaction between Sn and the hydroxyl O atoms [2.764(5) A˚], while the Sn atom in (4) adopts a trigonal bipyramidal geometry with a significant Sn(1)←O interaction [2.571(4) A˚]. [Copyright &y& Elsevier]