119Sn Chemical Shifts in five- and six-coordinate organotin chelates

¹¹⁹Sn chemical shifts, δ(¹¹⁹Sn), relative to Me₄Sn in five- and six-coordinate organotin chelates were measured by means of FT NMR spectroscopy. ¹¹⁹Sn resonances were found to lie between ca. ?90 and ?330 ppm in the five-coordinate compounds and between ca. ?125 and ?515 ppm in the six-coordinate derivatives. thus δ(¹¹⁹Sn) moves upfield by 60–150 ppm with a change of the coordination number of tin from four to five and by 130–200 ppm from five to six. the δ(¹¹⁹Sn) values were shifted depending on the nature of chelating ligands and this shift was discussed in terms of the bonding between the ligand and tin. Replacement of methyl groups attached to tin by phenyl groups in five- and six-coordinate compounds induces upfield shifts in δ(¹¹⁹Sn) parallel to those found in four-coordinate organotin halides.     

Synthesis and structural elucidation of bioactive triorganotin(IV) derivatives of sodium deoxycholate

Trimethyl (1), tributyl (2), and triphenyl tin (3) derivatives of sodium (R)-4-((3R,5R,8R,9S,10S,12S,13R,14S,17R)-3,12-dihydroxy-10,13-dimethyl-hexadecahydro-1H-cyclopenta[a]phenanthren-17-yl)pentanoate (sodium deoxycholate) were synthesized by refluxing sodium deoxycholate with the corresponding triorganotin(IV) chloride in 1?:?1?M ratio. All the three compounds were characterized by elemental analysis, infrared spectroscopy, ¹H, ¹³C, ¹¹⁹Sn NMR, and X-ray diffraction studies. From FT-IR spectra, Δν values proposed bridging or chelating behavior of the ligand. The three compounds gave a trigonal bipyramidal geometry in the solid state and tetrahedral geometry in solution. Single crystal of 1 showed polymeric trigonal bipyramidal geometry. Synthesized compounds obtained were screened for their antimicrobial and antitumor activities against A2780 cell line. Results revealed that only 2 showed significant antibacterial activity. However, all the three compounds exhibited promising antifungal and anticancer activities.     

Synthesis,structural, and spectral studies of diorganotin(IV) complexes with 2–hydroxy-5-methylbenzaldehyde-N(4)-cyclohexylthiosemicarbazone

Three new diorganotin(IV) complexes, [Me₂Sn(L)] (2), [Bu₂Sn(L)] (3), and [Ph₂Sn(L)] (4) [where H₂L (1) = 2-hydroxy-5-methylbenzaldehyde-N(4)-cyclohexylthiosemicarbazone] have been synthesized by reacting the corresponding diorganotin(IV) dichloride with H₂L (1) in absolute methanol in the presence of potassium hydroxide. All the compounds have been characterized by CHN analyses, UV–vis, FT-IR, ¹H, ¹³C, and ¹¹⁹Sn NMR spectroscopy. The molecular structures of H₂L (1) and 2 have been confirmed by single crystal X-ray diffraction analysis. H₂L (1) is found to be in the thiol tautomeric form. The X-ray structure of 2 showed that H₂L is a tridentate ligand and binds to the tin(IV) atom via the phenolic oxygen, azomethine nitrogen, and thiolate sulfur. Complex 2 has a triclinic structure and the coordination geometry of tin(IV) is distorted trigonal bipyramidal. The sulfur and oxygen are in axial positions while the azomethine nitrogen of 1 and two methyl groups occupy the equatorial positions. The C-Sn-C angles determined from ¹J(¹¹⁹Sn, ¹³C) for 2, 3, and 4 are 124.35°, 123.11°, and 123.82°, respectively. The values of δ(¹¹⁹Sn) for 2, 3, and 4 are ?153.4, ?180.59, and ?158.3 ppm, respectively, indicating five-coordinate tin(IV). From NMR data a distorted trigonal-bipyramidal configuration at each tin is proposed.     

Design,synthesis, and anticancer activity evaluation of novel aziridine-1,2,3-triazole hybrid derivatives

Some new 1-aryl-4-[(aziridine-1-yl)diaryl-methyl]-5-methyl-1H-1,2,3-triazole derivatives 7j–s were synthesized by the one-pot reaction of diaryl-(1-aryl-5-methyl-1H-1,2,3-triazol-4-yl)methanol compounds 6j–s formed from 1-aryl-5-methyl-1H-1,2,3-triazole-4-carboxylic acid derivatives. The new compounds 7j–s and 6j–s are investigated by ¹H and ¹³C NMR, MS, and IR. The anticancer activity of the synthesis target compounds was evaluated against human leukemia (HL-60) cells and human hepatoma G2 cells. Some of the compounds were highly efficient. The ¹H-NMR signals of the aziridine-ring cis-H/trans-H protons were found to be two group peaks at 1.800–1.884 and 1.183–1.327?ppm.     

Dérivés Alléniques de l'Étain,du Plomb et du Mercure. Signes Relatifs des Constantes de Couplage Métal-Proton á Travers Deux et Quatre Liaisons

Satellites corresponding to metal-proton coupling constants through two and four bonds are observed in PMR spectra of Pb, Sn and Hg allenic derivatives. The relative signs of these coupling constants are deduced from analysis of the satellite spectra: ²J(X? H) and ⁴J(X? H) are of opposite signs for X = ²⁰⁷Pb, ¹¹⁹Sn, ¹¹⁷Sn and of same sign for X = ¹⁹⁹Hg. Probable absolute signs of reduced coupling constants are discussed in relation to published data: ²K(X? C? H) is probably positive for X = ²⁰⁷Pb, ¹¹⁹Sn, ¹¹⁷Sn and ¹⁹⁹Hg. ⁴K(X? C?C?C? H) is probably negative for X = ²⁰⁷Pb, ¹¹⁹Sn, ¹¹⁷Sn and positive for X = ¹⁹⁹Hg.     

Synthesis,Structure–Activity Relationship of Some New Triorganotin(IV) Derivatives of Dipeptides as Anti-Inflammatory Agents

Abstract

New triorganotin(IV) derivatives of dipeptides with general formulae, R₃Sn(HL), where R = Me and Ph, and HL is the monoanion of histidinylalanine and histidinylleucine, have been synthesized and characterized on the basis of infrared (IR), multinuclear NMR (¹H, ¹³C, and ¹¹⁹Sn), and ¹¹⁹Sn Mössbauer spectroscopic studies. These derivatives exhibit distorted trigonal-bipyramidal geometry around tin in which dipeptide anion acts as bidentate ligand coordinating through carboxyl oxygen and amino nitrogen. Ph₃Sn(HHis-Ala),

Ph₃Sn(HHis-Leu), and previously reported Ph₂Sn(His-Ala), Me₂Sn(His-Ala), n-Oct₂Sn(His-Ala), Me₂Sn(His-Leu), n-Oct₂Sn(His-Leu), Ph₃Sn(HTyr-Phe), Ph₂Sn(Tyr-Phe), Bu₂Sn-(Tyr-Phe), and n-Oct₂Sn(Tyr-Phe) along with standard drugs, viz. phenyl butazone and indomethacin were screened for in vivo anti-inflammatory activity and acute toxicity (LD₅₀). Diorganotin(IV) derivatives are more active than triorganotin(IV) derivatives. Me₂Sn(His-Leu) shows the highest activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

1,1‐Organoboration of bis(trimethylstannyl)ethyne with trimethylsilyl‐ and dimethylsilyl‐dialkylboryl‐substituted alkenes: organometallic‐substituted allenes

The reactions of bis(trimethylstannyl)ethyne, Me₃Sn–C?C–SnMe₃ ( 4 ), with trimethylsilyl‐ or dimethylsilyl‐dialkylboryl‐substituted alkenes 1 – 3 afford organometallic‐substituted allenes 5 , 6 and 8 , 9 in high yield. In the case of (E)‐2‐trimethylsilyl‐3‐diethylboryl‐2‐pentene ( 1) , a butadiene derivative 7 could be detected as an intermediate prior to rearrangement into the allene. All reactions were monitored by ²⁹Si and ¹¹⁹Sn NMR, and the products were characterized by an extensive NMR data set (¹H, ¹¹B, ¹³C, ²⁹Si, ¹¹⁹Sn NMR). Copyright © 2003 John Wiley & Sons, Ltd.     

Synthesis of tri-n-butyltin taurocholate,taurodeoxycholate and glycocholate

The bile acids, taurocholic, taurodeoxycholic and glycocholic acid, were reacted with bis(tri-n-butyltin) oxide (TBTO) to form 1:1 derivatives. The water of reaction was removed with 2, 2-dimethoxypropane or by azeotropic distillation with benzene. The compounds were characterized by ¹³C and ¹¹⁹Sn NMR, IR, elemental analysis, molecular weight determination, DTA, TGA, and conductance measurements. The data indicated that tri-n-butyltin glycocholate forms a covalent ester, tin being tetracoordinated. The taurocholic and taurodeoxycholic acid derivatives contain one molecule of coordinated water. They partially dissociate in polar solvents. The taurocholic and glycocholic acid derivatives were tested in vitro as anticancer agents and exhibited ED₅₀ in the 0.2–0.4 ppm (mg kg^?1) range against KB epidermoid tumor and P-388 leukemia using NCI protocols.     

1H, 13C and 199Hg NMR Studies of the Complexation of HgCl2 by Imidazolidine-2-Thione and its Derivatives

Abstract

Mercury(II) complexes of imidazolidine-2-thione and its derivatives have been synthesized and their ¹H, ¹³C and ¹⁹⁹Hg NMR spectra measured. HgCl₂ forms L₂HgCl₂ type complexes (where L = imidazolidine-2-thione and its derivatives). The NH group of the ligand is shifted downfield by about +1.37 ppm in the ¹H NMR after complexation. The C-2 carbon in the ¹³C NMR is shifted by—6.50 ppm for mono N-substituted ligands, but by—5.30 ppm for N,N''-disubstituted ligands. The ¹⁹⁹Hg NMR resonance is shifted by about—60 ppm for N-substituted ligands, but—140 ppm shifts were observed for N',N'-disubstituted ligands.     

The chemistry,properties, and characterization of organotin(IV) complexes of 2-(N-naphthylamido)benzoic acid

2-(N-naphthylamido)benzoic acid was synthesized by the reaction of phthalic anhydride with naphthylamine in glacial acetic acid at room temperature. Complexes 1–9 were synthesized under reflux in good yield with general formula R_{4? n} SnL _n (R = Me, n-Bu, Ph, n-Oct, Bz and n = 2, 3), which were studied by microanalysis, IR, NMR (¹H, ¹³C, ¹¹⁹Sn), and mass spectrometry. Cytotoxicity of the synthesized compounds was checked against Brine-shrimp larvae. In vitro activities against some Gram-positive and Gram-negative bacteria and fungi were also determined. Antimicrobial activities show that species with tetrahedral geometry in solution are more toxic.     

Synthesis,spectral and antimicrobial studies of chlorodiorganotin(IV)[3(2′-hydroxyphenyl)-5-(4-substitutedphenyl) pyrazolinates]

Chlorodiorganotin(IV)pyrazolinates of the type R₂SnCl(C₁₅H₁₂N₂O?·?X) [where C₁₅H₁₂N₂O?·?X?=?3(2′-Hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X?=?H (a); CH₃ (b); OCH₃ (c); Cl (d) and R?=?Me, Pr ⁿ and Ph}] have been synthesized by reaction of R₂SnCl₂ with the sodium salt of pyrazolines in 1?:?1 molar ratio, in anhydrous benzene. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement and spectral studies [IR and multinuclear NMR (¹H, ¹³C and ¹¹⁹Sn)]. The bidentate behavior of the ligands was confirmed by IR, ¹H and ¹³C NMR spectral data. Trigonal bipyramidal structure around tin(IV) for R₂SnCl(C₁₅H₁₂N₂O?·?X) is suggested. The free pyrazoline and some chlorodiorganotin(IV) pyrazolinates have been screened for their antibacterial and antifungal activities. Some chlorodiorganotin(IV) pyrazolinates exhibit higher antibacterial and antifungal effect than free pyrazoline and some antibiotics.     

Group IV organometal derivatives of pyridine. I—A 1H and 13C NMR investigation of trialkylmetal derivatives of pyridine

The proton and carbon-13 NMR spectra of thirteen trialkylmetal derivatives of pyridine, several of which were previously unknown, have been recorded and analysed. The proton NMR spectra show variations in proton chemical shifts but not in proton-proton coupling constants when the metal substituent is changed; the ring proton-metal coupling constants ⁿJ(M? H) in the tin and lead derivatives correspond closely with the corresponding proton-proton couplings ⁿJ(H? H) in pyridine. The carbon-13 chemical shifts of the carbons bound to the metal can apparently be correlated with the electron-donating ability of the trialkylmetal group. In the trimethylstannylpyridines the value of ¹J(Sn? C_ring) varies greatly with the position of the Me₃Sn group.     

Synthesis,characterization, and insecticidal activity of new tin (IV) complexes

A three-component reaction of dimethyltin dibromide with imidazo[1,2-a]pyridine, pyridine derivatives, or isoquinoline and allyl bromide in refluxing ethanol affords the ionic complex, bis(1-allylcycloiminium) dimethyltetrabromostannate (II). The reaction involves N-allylation of cycloimine accompanied by the coordination of two bromide ions with the tin atom of dimethyltin dibromide. The complexes have been characterized by infrared and ¹H NMR, ¹³C NMR, and ¹¹⁹Sn NMR studies. The X-ray crystal structure analysis of a complex reveals the tin atom to be hexacoordinated and the dimethyltetrabromostannate (II) anion having octahedral geometry. Some of the complexes tested for their insecticidal activity are found to exhibit strong activity against Tribolium castaneum insect with LC₅₀ ranging from 0.4 to 0.8 ppm.     

Synthesis,characterization, and in vitro antibacterial and antifungal studies of tin(IV) thiohydrazide complexes

Reaction of tin dichloride and tin tetrachloride with cyclohexylamine-N-thiohydrazide (ChaThz) [L¹] and 1,3-propanediamine-N-thiohydrazide (PdaThz) [L²] results in [Sn(ChaThz)₂] (1), Sn(ChaThz)₂Cl₂] (2), [Sn(PdaThz)₂] (3), and [Sn(PdaThz)₂Cl₂] (4), in which the thiohydrazide coordinates to tin through imine nitrogen and thioamide sulfur. The ratio metal?:?ligand was 1?:?2 for all complexes. The tin(IV) thiohydrazide complexes were characterized by elemental analysis, IR, UV-Vis, ¹H-NMR, ¹¹⁹Sn NMR, and mass spectral studies. Using the disc diffusion method, the ligands and metal complexes were screened for in vitro antibacterial activities against four pathogenic bacteria, Escherichia coli, Staphylococcus aureus, P. aeruginosa, and Bacillus cereus and for antifungal activities against Aspergillus flavus, A. carbonarius, A. niger, and A. fumigatus. While the tin(IV) complexes exhibited moderate antifungal activities, their parent ligands showed much higher and long-lasting broad spectrum of bioactivity against fungal growth. This was particularly the case for L¹ whose fungal inhibitory activity by the end of the experimental period was comparable and, for the most part, more pronounced than that of AmB. This higher activity of L¹ was maintained specifically against S. Aureus but in general, bacteria were more susceptible to complexes than ligands.     

Diorganotin complexes of carboxylates: synthesis and characterization

Diorganotin complexes of monoisopropyl and monomethyl nadiate, succinate, and phthalate were synthesized and characterized by elemental analysis, FT-IR, ¹H NMR, ¹³C NMR, and ¹¹⁹Sn NMR spectroscopic techniques. The spectroscopic investigation demonstrated that carboxylate is bidentate in the diorganotin complexes. On the basis of ¹ J(¹¹⁹Sn–¹³C) and ² J(¹¹⁹Sn–¹H) values, C–Sn–C bond angles were also calculated. The newly synthesized complexes were also screened for their antibacterial activities against Gram-positive and Gram-negative pathogenic strains of bacteria.     

Substituent chemical shifts of the organotin moiety in compounds of the type RSnMenCl3 − n (n = 0 to 3; R = n-alkyl)

The ¹³C and ¹¹⁹Sn NMR spectra of 33 organotin compounds of the type RSnMe_nCl_{3 ? n} and related types are discussed. The substituent effects of the groups SnMe₃, SnMe₂Cl, SnMeCl₂ and SnCl₃ (and of some related groups) on the carbon chemical shifts in the alkyl group R have been determined; the SnMe₃ group causes a small upfield shift of the carbon attached to it, while the other groups cause downfield shifts. The shifts show a monotonic change on replacing methyl groups in Me₃Sn by chlorine atoms. The effects on carbons further removed from the tin atom are discussed. Variation in R causes little change in ⁿJ(Sn? C) or δ(¹¹⁹Sn).     

Synthesis and spectroscopic studies of diorganotin(IV) adducts based on cyclotriphosphazene scaffolds with exocyclic pyrazolyl substituents

Functionalized cyclotriphosphazenes with four pyrazolyl substituents have been employed for the synthesis of two new organotin complexes. These new compounds have been characterized by elemental analysis and IR, ¹H, ³¹P and ¹¹⁹Sn NMR spectroscopy. On the basis of these data, pyrazolylcyclotriphosphazene is bis-bidentate neutral ligand coordinating to two SnMe₂Cl₂ molecules in the resulting adducts. Coordination occurs only via the pyrazolyl nitrogens; cyclotriphosphazene ring nitrogens are not involved in coordination. The ¹¹⁹Sn NMR data are consistent with increasing of coordination number of tin(IV) in solution.     

Synthesis,spectroscopic characterization,crystal structure,and anti-bacterial activity of diorganotin(IV) complexes with 5-bromo-2-hydroxybenzaldehyde-N(4)-ethylthiosemicarbazone

Three new diorganotin(IV) complexes, [Me₂Sn(BDET] (2), [Bu₂Sn(BDET)] (3), and [Ph₂Sn(BDET)] (4), were synthesized by reacting R₂SnCl₂ (R = Me, Bu, and Ph) with 5-bromo-2-hydroxybenzaldehyde-N(4)-ethylthiosemicarbazone [H₂BDET, (1)] in the presence of KOH in absolute methanol. The newly synthesized complexes were characterized by elemental analysis, molar conductivity, UV–vis, FT-IR, ¹H, ¹³C, and ¹¹⁹Sn NMR spectroscopies. The molecular structure of 4 was confirmed by X-ray crystallography. X-ray crystallography revealed that the doubly deprotonated O,N,S-tridentate thiosemicarbazone coordinates to tin(IV), resulting in a distorted trigonal bipyramidal geometry. Their ¹H, ¹³C, and ¹¹⁹Sn NMR spectra support a five-coordinate tin(IV) in solution for all complexes, in accord with the solid-state X-ray structure determined for 4. Compounds 1–4 were evaluated for their antibacterial activities against Staphylococcus aureus, Enterobacter aerogenes, Escherichia coli, and Salmonella typhi. The results exhibited that 2–4 were active with comparable potency compared to the standard drug. Antibacterial studies also indicated that the complexes have potential for biological evaluation.     

Synthesis,Characterization, and Structures of Tetrakis(2-Pyridyl)Tin Compounds

Abstract

Reactions of 2-bromopyridine and 2-bromo-6-methylpyridine with n-BuLi and tin tetrachloride afforded Sn(2-py)₄ (1a) and Sn(6-Me-2-py)₄ (1b), respectively. The identities of the two compounds were unambiguously proved by microanalyses, NMR (¹H, ¹³C, ¹¹⁹Sn) spetroscopy, and single-crystal X-ray diffraction studies.     

Fourier transform NMR investigations of organotin compounds : VIII. Propenyl- and isopropenyl-tin compounds; detection and identification of isomers using 119Sn and 13c NMR

Starting from the equilibrium mixture of cis- and trans-1-bromo-1-propene, isomeric mixtures of compounds Me_n Sn(CH=GHMe)_4-n (n = 0–3) have been prepared and studied. While proton NMR only allows distinction between the methyltin signals of the various isomers (except where n = 3), the ¹³C spectra show separate signals for almost all isomeric carbons even when n = 0. In the ¹¹⁹Sn spectra the signals due to the various isomers are separated by ca. 20 ppm for a given value of n; the peak areas can be used to estimate the proportions of cis- and trans-propenyl residues present in the mixtures. Addition of 2-bromo-propene to the starting 1-bromo-1-propenes leads to the formation of further isomers, which can in all cases be observed and identified in the ¹¹⁹Sn spectra; ¹¹⁹Sn shifts can be calculated using the shifts for the Me₃SnC₃H₅ isomers as increments.