Synthesis, Structural Investigations and Biological Screening of Diorganotin(IV) Complexes Derived from 5,5-Diethyl Sodium Barbital

Some biologically important tin(IV) complexes derived from 5,5-diethyl sodium barbital have been synthesized and characterized through various analytical and spectroscopic techniques such as IR, 1H-, 13C-NMR and 119mSn mssbauer. On the basis of these spectroscopic techniques, octahedral geometry has been assigned to all the novel compounds. These complexes, soluble in DMSO and DMF, were screened against a wide range of microorganisms. The results proved that the diphenyltin(IV) and dibutyltin(IV) complexes exhibit excellent activity against all types of microorganisms, while the rest of the compounds show significant activity that can be used during the biological study.     

Synthesis,structure and cytotoxic activity of binuclear phenyltin(IV) complexes with N,N′‐bis(2‐hydroxybenzyl)‐1,2‐ethanebis(dithiocarbamate) ligand

Two new dinuclear phenyltin(IV) complexes derived from N,N′‐bis(2‐hydroxybenzyl)‐1,2‐ethanebis(dithiocarbamate) ligand, [2‐HOC₆H₄CH₂N(CS₂SnPh₃)CH₂]₂ ( 1 ) and [2‐HOC₆H₄CH₂N(CS₂SnClPh₂)CH₂]₂ ( 2 ) have been synthesized and characterized by elemental analysis, IR and NMR (¹H, ¹³C and ¹¹⁹Sn) spectra. The crystal structures of complexes 1 and 2 were determined by X‐ray single crystal diffraction and show that the dithiocarbamate ligand is coordinated to the tin atom in the anisobidentate manner and the tin atom is five‐coordinated. The coordination geometry of tin atom is best described as an intermediate between trigonal bipyramidal and square pyramidal with τ‐values of 0.63 and 0.53, respectively. Intermolecular hydrogen bonds (O H···S and O H···Cl) in 1 and 2 connect neighboring molecules into a one‐dimensional supramolecular chain with the centrosymmetric cyclic motifs. Complex 1 has potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while complex 2 displays weak cytotoxic activity. Copyright © 2011 John Wiley & Sons, Ltd.     

Tin(IV) Complexes of 1,5-Diphenylthiocarbazone and Thiosemicarbazide: Synthesis,X-Ray Characterization,and Biological Activity

Abstract

The reaction of Me₂SnCl₂ with dithizone or thiosemicarbazide produced two novel di-organotin derivatives in good yields, which were characterized by X-ray diffraction. The crystal structures show that the compounds present a distorted pentacoordinated tin(IV) metal center. The antimicrobial activity of the new compounds was studied against Gram-negative (Escherichia coli, Klebsiella pneumonia, Salmonella enteritidis) and Gram-positive (Staphylococcus aureus) bacteria, and the yeast Saccharomyces cerevisiae. It was observed that the coordination of tin metal has a pronounced effect on the microbial activities of the ligands. All the tin complexes have shown higher antimicrobial effect than the free ligands.

GRAPHICAL ABSTRACT     

基于类salen配体的二苯基锡配合物的合成、抗肿瘤活性及其与DNA相互作用

利用类salen配体二苯乙二酮苯甲酰腙或二苯乙二酮水杨酰腙与二苯基二氯化锡反应,合成了2个二苯基锡配合物[(C_6H_5(O)C=N—N=C(Ph)—(Ph)C=N—N=C(O)—C_6H_5)_2SnPh_2(CH_3OH)]·3CH_3OH (1)和 [(o-OH—C_6H_4(O)C=N—N=C(Ph)—(Ph)C=N—N=C(O)—(o-OH—C_6H_4))_2SnPh_2(CH_3OH)]·CH_3OH (2),通过IR、~1H NMR、~(13)C NMR、~(119)Sn NMR、元素分析、HRMS 以及X射线单晶衍射等表征了配合物结构。测试了配合物1、2的热稳定性及其对癌细胞的体外抑制活性,发现配合物2对癌细胞NCIH460、HepG2、MCF7表现出略优的抑制活性。利用紫外可见吸收光谱、荧光猝灭光谱研究了配合物2与ct-DNA之间的相互作用,结果表明配合物以嵌入模式与DNA结合。     

Synthesis,Characterization, Theoretical Studies,and Antimicrobial/Antitumor Potencies of Salen and Salen/Imidazole Complexes of Co (II), Ni (II), Cu (II), Cd (II), Al (III) and La (III)

Although salens and imidazoles are well-studied motifs among bioactive and therapeutic agents, their properties when combined in transition metal complexes are not well developed. To explore the structure/reactivity of this class of compounds, a salen-based ligand, namely (2,2′-{1,2-ethanediylbis[nitrilo(E)methylylidene]}diphenol, S), and its binary (MS) and ternary (MSI) complexes (I = imidazole; M = Co (II), Ni (II), Cu (II), Cd (II), Al (III), and La (III)) have been synthesized and fully characterized by standard physicochemical and theoretical methods. Evidence from structural analysis tools along with DFT modeling revealed an unusual monobasic tridentate salen binding mode, involving the phenolic oxygen, the nitrogen of the azomethine group, and NH group formed via phenol-to-cyclohexadienone tautomerization, giving rise to a general molecular formula of MSI complexes as [M(S)(I)₂(Cl)] for M (II) = Co, Ni, Cu and Cd or [M(S)(I)(Cl)₂] for M (III) = Al and La, respectively. The antimicrobial activities of S, MS, and MSI were screened against several bacterial and fungal strains. Of all tested complexes, CdS and CuSI were the most effective antimicrobials, giving larger inhibition zones than the reference antibiotics. The antimicrobial efficacy for the MS complexes follows the order: CdS > gentamicin > CuS > NiS > CoS > LaS > AlS > S, whereas MSI complex, potencies are ordered as CuSI > gentamicin > CdSI >NiSI > CoSI > LaSI > AlSI > S. In vitro cytotoxicity screening of MSI complexes disclosed that both CuSI and CdSI exhibited higher activity against human liver (Hep-G2) and breast (MDA-MB231) carcinoma cell lines than the reference (cisplatin) drug. The satisfactory bioactivities observed for several of these compounds supports the underlying design idea for combining important bioactive motifs for possible therapeutic benefit.     

Thermal Studies of Di- and Triphenyltin(IV) Complexes of Salicylhydroxamic Acid

Thermal decomposition of di- and triphenyltin(IV) complexes derived from potassium salicylhydroxamate (KSHA) of compositions Ph2SnCl(SHA), Ph2Sn(SHA)2 and Ph3Sn(SHA) has been studied by TG, DTG and DTA. Based upon thermal mass losses the transitory formation of diphenyltin oxide, Ph2SnO as the possible intermediate from the decomposition pattern of all the three complexes has been proposed. Both DTG and DTA give well-defined peaks in the appropriate regions. These studies reveal the formation of SnO2 as the ultimate product. This revised version was published online in July 2006 with corrections to the Cover Date.     

New Dithiocarbamate Compounds from Organotin(IV)

Abstract

A series of new organotin(IV) dithiocarbamate compounds of type R_nSn (S₂CNR′R″)_4-n (n = 2, 3; R = dimethyl, dibutyl, diphenyl, triphenyl and tert-butyl; R′ = methyl, ethyl, benzyl; R″ = isopropyl, ethyl, ethanol) have been successfully synthesized. Elemental analysis showed that the percentage of the elements conformed to the general formula of these compounds. The important peaks of the infrared spectra for the stretching mode ν(C?N), ν(C?S), and v(Sn-S) for the compounds were observed in the area of 1440–1480 cm^?1, 940–1000 cm^?1, and 340–90 cm^?1, respectively. The ¹³C NMR spectra showed the most important peak for N¹³CS₂ chemical shifts were observed in the range 190–210 ppm. X-ray single crystal studies for several structures of these compounds showed that the chelating mode of the dithiocarbamate groups to the central tin atoms were either bidentate or anisobidentate.

GRAPHICAL ABSTRACT     

Crystallographic report: Bis[tri(o‐chlorobenzyl)tin(IV)] piperazinylbisdithiocarbamate

The centrosymmetric structure of (o‐C₆H₄CH₂)₃SnS₂CN(CH₂CH₂)₂NCS₂Sn(CH₂C₆H₄‐o)₃ features chelating dithiocarbamate ligands, so that a trigonal bipyramidal C₃S₂ coordination geometry for tin results. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis,Characterization, Thermal Analysis,DFT, and Cytotoxicity of Palladium Complexes with Nitrogen-Donor Ligands

Three new palladium complexes ([Pd(DABA)Cl₂], [Pd(CPDA)Cl₂], and [Pd(HZPY)Cl₂]) bearing dinitrogen ligands (DABA: 3,4-diaminobenzoic acid; CPDA: 4-chloro–o-phenylenediamine; HZPY: 2-hydraziniopyridine) were synthesized, characterized, and tested against breast cancer (MCF-7), prostate carcinoma cell line (PC3) and liver carcinoma cell line (HEPG2). [Pd(DABA)Cl₂] complex exhibited the highest inhibition percentage, lying between 68–71%. The hydrolysis mechanism of each palladium complex, the key step preceding the binding to the biological target, as well as their photophysical properties were explored by means of DFT and TDDFT computations. Results indicate a faster hydrolysis process for the Pd(DABA)Cl₂ complex. The computed activation energies for the first and second hydrolysis processes suggest that all the compounds could reach DNA in their monohydrated form.     

Synthesis, Characterization and Biological Activity of Diorganotin（IV） Complexes of N-（3,5-Dibromosalicylidene）-α-amino Acid

The diorganotin（Ⅳ） complexes of N-（3,5-dibromosalicylidene）-α-amino acid, R2Sn（2-O-3,5-Br2C6H2CH= NCHRCOO）（where R=H, Me, i-Pr, Bz; R＇=n-Bu, Cy）, were synthesized by the reactions of diorganotin dichlorides with in situ formed potassium salt of N-（3,5-dibromosalicylidene）-α-amino acid and characterized by elemental analysis, IR and NMR （^1H, ^13C and ^119Sn） spectra. The crystal structures of n-Bu2Sn（2-O-3,5-Br2C6H2CH= NCHRCOO）（R=i-Pr, Bz） and Cy2Sn（2-O-3,5-Br2C6H2CH=NCHRCOO）（R=Me, Bz） were determined by X-ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry to form five- and six-membered chelate rings with the tridentate ligand. Bioassay results indicated that the compounds possess better in vitro antitumour activity against three human tumour cell lines, HeLa, CoLo205 and MCF-7, than cis-platin and moderate anti-bacterial activity against two bacteria, E. coli and S. aureus.     

Diphenyltin(IV) dithiocarbamate macrocyclic scaffolds as potent apoptosis inducers for human cancer HEP 3B and IMR 32 cells: synthesis,spectral characterization,density functional theory study and in vitro cytotoxicity

Binuclear diphenyltin(IV) dithiocabamate macrocyclic complexes [(Ph₂Sn^IV)₂‐μ²‐bis{(κ²S,S‐S₂CN(R)CH₂CONHC₆H₄)₂O}] (R = ⁱPr ( 1 ), ^sBu ( 2 ), ⁿBu ( 3 ), Cy ( 4 ), 2‐furfuryl ( 5 ) or benzyl ( 6 )) were synthesized through a self‐assembly process involving novel diamino precursors 4,4′‐bis(2‐(alkylamino)acetamido)diphenyl ethers ( L¹ , L² , L³ , L⁴ , L⁵ , L⁶ ), CS₂ and Ph₂SnCl₂. These were characterized using microanalysis and relevant spectroscopic methods. The geometry of all compounds was optimized using the density functional theory method. In vitro cytotoxic activity was evaluated against HEP 3B (hepatoma) and IMR 32 (neuroblastoma) using the MTT assay. Notably, complexes 1 , 2 , 3 , 4 , 5 , 6 were found to be extremely active against both cell lines and cytotoxicity data confirmed their 16‐fold better potency compared to cisplatin, a well‐known antineoplastic drug. Flow cytometric analysis of annexin V–propidium iodide‐stained cells demonstrated the ability of L⁵ , 4 and 6 to induce apoptosis in HEP 3B and IMR 32 cells, required for major therapeutic implication in cancer therapy. The extraordinary potency of binuclear complex 4 can be correlated with higher LUMO energy together with the greatest value of residual charge on the Sn(IV) centre among the compounds under investigation. Copyright © 2015 John Wiley & Sons, Ltd.     

水杨醛双缩二氨基硫脲二丁基锡配合物的合成及杀菌活性研究

利用1,5-水杨醛双缩二氨基硫脲席夫碱与二丁基氧化锡为原料,在苯-甲苯混合溶剂中回流反应合成了有机锡席夫碱配合物,用元素分析、红外光谱、核磁共振谱对目标化合物结构进行了结构表征,并用X-射线单晶衍射对其结构进行了确证.晶体结构分析表明,标题配合物的晶体属三斜晶系,P-1空间群,每个独立单元中含有两个分子结构单元,晶胞参数:a=1.29705(6)nm,b=1.36654(7)nm,c=1.68517(8)nm,α=72.059(1)o,β=87.339(1)o,γ=63.435(1)o,V=2.5270(2)nm3,Z=4,Dcalc =1.433 g/cm3,μ=1.119 mm-1,F(000)=1112,R1=0.0563,wR2=0.1530.分子间经典的N-H...N氢键使分子相互缔合形成二聚体,后者再通过范德华作用力结合堆积形成完全的晶体结构.杀菌活性测定结果表明,标题化合物及其类似物的杀菌活性具有较大的选择性,对苏云金杆菌(B.thuringiensis)和枯草杆菌(B.Subtilis)的杀菌能力较高,而对大肠杆菌(E.Coli)和金黄色葡萄球菌(S.Aureus)的杀菌能力较低.     

Synthesis, Characterization and Properties of Organotin Complexes Dibutyltin（Ⅳ） Bis（heteroaromatic carboxylate） and Crystal Structure of Dibutyltin（Ⅳ） Bis（2-thiazolylcarboxylate）

The six organotin complexes dibutyltin(IV) bis(heteroaromatic carboxylate) were synthesized by the reaction of (n‐Bu)2SnO with heteroaromatic carboxylic acid in 1:2 molar ratio. These complexes have been characterized by elemental analysis, IR, ¹H, ¹³C and ¹¹⁹Sn NMR. The crystal structure of dibutyltin(IV) bis(2‐thiazolylcarboxylate) was determined by X‐ray single crystal diffraction. This compound is a weakly bridged dimer through weak interaction Sn···O between molecules. The tin atoms took six‐coordinate skew‐trapezoidal bipyramidal geometry. The crystal of complex 3 belongs to monoclinic symmetry with space group P2₁/c, a=1.863(2) nm, b=2.220(3) nm, c=1.0395(10) nm, β=90.275(16)°, Z=8, V=4.292(8) nm³, D_c=1.514 Mg/m³, μ=1.406 mm^‐1, F(000)=1968, S=0.999, R=0.0549, wR=0.1011.     

Thermal Studies of the Dibutyltin(IV) Complexes of Schiff Bases Derived from Amino Acids

The thermal decomposition using TG, DTG and DTA, of seven complexes of the types Bu₂SnL(I) and Bu₂SnL(II) (where H₂L(I)=Schiff base derived from acetylacetone and glycine [H₂L-1(I)] or L-leucine [H₂L-4(I)] or methionine [H₂L-5(I)] or phenylglycine [H₂L-6(I)]; H₂L(II)=Schiff base derived from o-hydroxynaphthaldehyde and β-alanine [H₂L-2(II)] or DL-valine [H₂L-3(II)] or L-leucine [H₂L-4(II)] is shown to fall into one of two categories, viz, (1) Bu₂SnL(I) complexes that decompose without melting to give SnO as the final tin containing product, (2) Bu₂SnL(II) complexes that melt and then decompose to give SnO. Mathematical analysis of TG data using Coats-Redfern equation, Horowitz-Metzger equation, and Fuoss method shows that the first order kinetics is applicable in all the complexes except Bu₂SnL-2(II). Kinetic parameters such as the energy and entropy of activation and pre-exponential factor are reported. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis,characterization and cytotoxic activity of diorganotin (IV) complexes with 4H-pyrido[1,2-a]pyrimidin-4-one derivatives

The coordination behaviour of the diorganotin (IV) compounds R₂SnCl₂ (where R = Me, Ph) with 4H-pyrido [1,2-a] pyrimidin-4-one derivatives (L) has been described. The complexes R₂SnCl₂ · L obtained have been characterized physicochemically and spectroscopically. The pyrimidin-4-one ligands were found to coordinate with R₂SnCl₂ species in a monodentate fashion, mainly via the oxygen atom of the 4-one group or possibly via the nitrogen atom of the (SINGLE BOND)C(DOUBLE BOND)N linkage (the less sterically hindered nitrogen of the pyrimidine derivative) to give pentacoordinate tin complexes. Of the complexes selected to be screened against five tumour cell lines, some exhibited significant in vitro activity.     

Synthesis,Crystal Structure,Theoretical Calculations,Antibacterial Activity,Electrochemical Behavior,and Molecular Docking of Ni(II) and Cu(II) Complexes with Pyridoxal-Semicarbazone

New Ni (II) and Cu (II) complexes with pyridoxal-semicarbazone were synthesized and their structures were solved by X-ray crystallography. This analysis showed the bis-ligand octahedral structure of [Ni(PLSC-H)₂]·H₂O and the dimer octahedral structure of [Cu(PLSC)(SO₄)(H₂O)]₂·2H₂O. Hirshfeld surface analysis was employed to determine the most important intermolecular interactions in the crystallographic structures. The structures of both complexes were further examined using density functional theory and natural bond orbital analysis. The photocatalytic decomposition of methylene blue in the presence of both compounds was investigated. Both compounds were active toward E. coli and S. aureus, with a minimum inhibition concentration similar to that of chloramphenicol. The obtained complexes led to the formation of free radical species, as was demonstrated in an experiment with dichlorofluorescein-diacetate. It is postulated that this is the mechanistic pathway of the antibacterial and photocatalytic activities. Cyclic voltammograms of the compounds showed the peaks of the reduction of metal ions. A molecular docking study showed that the Ni(II) complex exhibited promising activity towards Janus kinase (JAK), as a potential therapy for inflammatory diseases, cancers, and immunologic disorders.     

二对甲基苄基锡芳甲酰腙配合物的合成、晶体结构及生物活性

将二对甲基苄基二氯化锡分别与2-[(4-硝基-苯甲酰基)-亚肼基]-3-苯基-丙酸或2-[(噻吩-2-羰基)-亚肼基]-3-苯基-丙酸反应,合成了2个以Sn_2O_2四元环为中心对称的二对甲基苄基锡配合物(C1、C2),通过元素分析、IR、~1H NMR、~(13)C NMR、~(119)Sn NMR、HRMS以及X-射线单晶衍射等表征了配合物的结构。测试了配合物C1、C2对癌细胞NCI-H460、HepG2、MCF7的体外抑制活性,结果表明,配合物C1、C2对3种癌细胞都有较好的抑制作用,C1略优于C2。通过紫外光谱、荧光光谱、粘度法测试配合物C1与小牛胸腺DNA的相互作用方式,结果均显示配合物C1与小牛胸腺DNA的作用是插入结合,并且作用效果较强;凝胶电泳研究表明,配合物C1能够有效地将超螺旋DNA pBR322切割成缺刻型DNA。     

Synthesis and Characterization of Diphenyltin(IV) Dicarboxylates Containing Germanium

Twelve new germanium substituted diphenyltin dipropionates with the general formula (R¹GeCHR²‐CHR³COO)₂SnPh₂ where R¹ = N(CH₂CH₂O)₃, (C₆H₅)₃ and (CH₃C₆H₄)₃, R² = H, CH₃, C₆H₅, p‐CH₃C₆H₄, p‐CH₃OC₆H₄, p‐ClC₆H₄, and R³ = H, CH₃ have been synthesized by the reaction of diphenyltin oxide with a germanium substituted propionic acid. All the compounds were characterized by elemental analysis, IR, multi‐nuclear (¹H, ¹³C, ¹¹⁹Sn) NMR and Mössbauer spectroscopies as well as mass spectrometry. The in vitro antibacterial activity of selected compounds is also reported.