UV-Vis Spectrum and the Third-order Nonlinear Optical Properties of the Chiral Camphorderived β-diketonate Platinum Complexes

UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G＊ level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down.

THE CHIRAL SELECTIVITY IN ACROSS－MEMBRANE TRANSPORT OF 1，2－DIAMINOCYCLOHEXANE PLATINUM（II）COMPLEXES AND THE CONTRIBUTION OF LEAVING GROUPS

The uptake kinetics of platinum(II)complexes of 1,2 -diaminocyclohexane(dach)isomers(1R,2R-dach, 1R,2S-dach. 1S,2S-dach) with various leaving groups, Chloride(CI), oxalate (OX),squaric acid(SA), and demethylcantharic acid (DA) was studied in the plasma isotonic buffer. The experimentalresults show that across-membrane transport of all the platinum complexes studied follows a firstorder Kinetic process and a passive diffustion mechanism. The uptake rate constants of these platinum(II)complexes decrease in the following sequence with the k value(h-1):CI>SA>OX>DA. It isnoteworthy that the k values of the platinum(II)complexes with same leaving group reduce as: 1R,2R-dach>1R,2S-dach>1S,2S-dach. Based on these results, it is firstly suggested that the erythocytemembrane recognizes the chirality of these platinum complexes.

Synthesis, characterization and biocidal properties of platinum metal complexes derived from 2,6-diacetylpyridine (bis thiosemicarbazone)

The coordination compounds of PdII, PtII, RhIII and IrIII metal ions with a Schiff base ligand (L) i.e. 2,6- diacetylpyridine bis(thiosemicarbazone) have been synthesized and characterized by elemental analyses, molar conductance, magnetic susceptibility measurements, IR, NMR and electronic spectral studies. On the basis of molar conductance and elemental analyses the complexes were found to have composition [M(L)]Cl2 and [M’(L)Cl]Cl2, where M = Pd(II), Pt(II) and M’ = Rh(III), Ir(III). The spectral studies reveal that the complexes possess monomeric composition. Complexes of PdII and PtII were found to have four coordinated square planar geometry whereas the complexes of RhIII and IrIII posses six coordinated octahedral geometry. The ligand field parameters were calculated using various energy level diagrams. In vitro synthesized compounds and metal salts have been tested against some species of plant pathogenic fungi and bacteria in order to assess their antimicrobial properties.

SYNTHESIS AND CHARACTERIZATION OF DVE-CO-MA DERIVATIVES OF CIS- PLATINUM COMPLEXES

Copolymer of divinyl ether and maleic anhydride (DVE-co-MA) derivatives of cis-platinum complexes were synthesized and characterized by elementary analysis, IR and XPS ( X-ray photoelectron spectroscopy). The behavior of the products in biological environment was also studied. UV-visible and fluorescence spectra show that these polymer derivatives are able to exchange ligands with selected nucleophilic groups in biological environment.

Preparation of Platinum(II) Complexes with 1-β-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide and its Deoxy-analogue

The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF.

Silica-supported Polysiloxanes with Dithiacrown Ether Groups and Their Platinum Complexes

The present paper represents the syntheses of polypropyloxymethyldithia 15-crown-5 and 18-crown-6 supported on silica and their platinum complexes. The platinum complexes are effective catalysts for the hydrosilylation of olefins with triethoxysilane. The influences of temperature, amount of platinum complexes used and the nature of olefins used on the catalytic activity of the complexes are also investigated in this paper.

Synthesis, Spectral and Antimicrobial Studies of Bis (Cyclopentadienyl) Titanium (IV) Bis (O,O’-Dialkyl and Alkylenedithiophosphate) Complexes

A new complexes of Cp2Ti[S2P(OR)2]2 (where R = Et, Pr-n, Pr-i, Bu-i and Ph) and Cp2Ti[S2POGO]2 (where G = -CH2CMe2CH2-, -CH2CEt2CH2- and -CMe2CMe2-) were prepared by the dropwise addition of the appropriate O,O’-dialkyl or -alkylenedithiophosphoric acid to biscyclopentadienyl titanium dichloride in 1:2 molar ratio and refluxed in benzene solution. These novel deep red colored complexes were characterized by elemental analyses, molecular weight measurements and spectroscopic techniques (IR., NMR 1H, 13C and 31P NMR). These titanium (IV) dithio complexes have also been screened for their antibacterial activities.

Current Status for Oral Platinum (IV) Anticancer Drug Development

Platinum-based chemotherapeutic drugs such as cisplatin, carboplatin and oxaliplatin are widely applied for the treatment of various types of tumors. However, poor solubility, serious side effects, and more importantly, the intrinsic and acquired resistance limit their clinical applications. These factors motivate scientists to design and synthesize novel and more potent analogues lacking disadvantages of clinical platinum drugs. Platinum (IV) complexes are one of representatives. In this review, we summarized the investigations undertaken into Platinum (IV) antitumor compounds since Rosenberg first noted their antitumor activity. The synthesis method and mechanism of action of Platinum (IV) complexes are outlined, as well as their chemical and pharmacological properties. Recent advances in Platinum (IV) anticancer agents that have been in clinical trials and photoactivatable Platinum (IV) complexes are also summarized, and the purpose here is to provide insight into the requirements for the antitumor activity of Platinum (IV) complexes and a basis for progressing in a new platinum compound.

Adsorption and reduction of platinum(Ⅳ) chloride complex ions on activated carbon

The adsorption kinetics of platinum（IV） chloride complex ions on the activated carbon Norit GF40 was investigated. Experiments were carried out at different initial concentrations of Pt（IV） chloride complex ions, temperature, rate of mixing and pH. It was found that the value of activation energy of the studied process is equal to 19.7 kJ/mol. From the ICP MS analysis it was confirmed that platinum ions （Pt（IV） and Pt（II）） are removed from the solution due to the adsorption and are further reduced to the metallic state. Such mechanism was confirmed by XPS analysis which showed that on the carbon surface three forms of platinum species, i.e. Pt（0）, Pt（II） and Pt（IV）, exist. The presence of platinum in the solution at different oxidation states was also confirmed spectrophotometrically by identification of their characteristic absorption bands. The metallic form of Pt present on the surface of activated carbon was observed in the form of small spherical islands with the diameter not exceeding 500 nm. Those islands consist of smaller, flake-shape particles with a thickness of about 35 nm.

Studies of the Intramolecular Aromatic-ring Stacking Interactions in the Ternary Platinum(Ⅱ) Complexes

The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.

Platinum complexes as phosphorescent emitters in highly efficient organic light-emitting diodes

Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes （OLEDs） were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.

Synthesis, Characterization and Cytotoxicity of Ammine/Methylamine Platinum(Ⅱ) Complexes with Carboxylates

Seven novel platinum （Ⅱ） complexes [ Pt（Ⅱ） （NH3） （CH3NH2）X2] （Ⅰ-Ⅶ ） （ X： CH3COO^-, CH2CICOO^- , CHCI2COO^- , C6H5-COO^- , p-CH3O--C6H4-COO^- , p-NH2-C6H4-COO^- , p-NO2--C6H4- COO^-） were prepared and characterized by means of elemental analysis, molar conductivity, thermal analysis, IR, UV, and ^1H NMR spectrometries. The cytotoxicity against HCT-8, BGC-823, MCF-7, EJ, and HL-60 cell lines increases in the following sequence： cisplatin 〉 Ⅳ 〉 Ⅴ 〉 Ⅵ 〉 Ⅶ 〉 Ⅰ 〉 Ⅱ 〉 Ⅲ. Moreover, the complexes （ Ⅰ --Ⅻ） display substantially greater activities agaist EJ and HL-60 cell lines than those against the cell lines from other carcinomas. They can induce a concentration-dependent accumulation of HL-60 cells in the G2/M phase of the cell cycle as cisplatin. There is no significant correlation between total DNA platination levels and cytotoxicity of the complexes.

Synthesis, spectral characterization and biological activities of Organotin(IV) complexes with <i>ortho</i>-vanillin-2-hydrazinopyridine (VHP)

Five new organotin(IV) complexes of ortho-vanillin-2-hydrazinopyridine hydrazone with formula [RnSnCl4–n(VHP)] [R = Me2, n = 2 (2);R = Ph2, n = 2 (3);R= nBu2, n = 2 (4);R = nBu, n = 2 (5) and R = 1, n = 0 (6)] have been synthesized by direct reaction of ortho-vanillin-2-hydrazinopyridine hydrazone [(VHP), (1)], base and organotin(IV) chloride(s) in absolute methanol. The hydrazone ligand [(VHP), (1)] and its organotin(IV) complexes (2-6) have been characterized by UV-Visible, FT-IR and 1H NMR spectral studies. Spectroscopic data suggested that in the complexes (2-4), the ligand (1) acted as a neutral bidentate ligand and is coordinated to the tin(IV) atom via the azomethine nitrogen and pyridyl nitrogen atoms, whereas the ligand (1) acted as a uninegative tridentate ligand and coordinated to the tin(IV) atom through phenolic-O, azomethine-N and pyridyl-N atoms in complexes (5-6). The toxicity of the ligand (1) and its organotin (IV) complexes (2-6) were determined against Artemia salina. Organotin(IV) complexes showed moderate activity against Artemia salina. The ligand (1) and its organotin(IV) complexes (2-6) were also tested against four types of bacteria namely Bacillus cereus, Staphylococcus aureus, Escherichia coli and Enterobacter aerogenes. All organotin(IV) complexes and the free ligand (1) showed better antibacterial activities against bacteria. Among the organotin(IV) complexes (2-6), diphenyltin(IV) complex (3) showed higher activity against the four types of bacteria.

Synthesis, spectral, 3D molecular modeling and antibacterial studies of dibutyltin (IV) Schiff base complexes derived from substituted isatin and amino acids

New dibutyltin(IV) complexes of Schiff base derived from 5-chloroindoline-2,3-dione, indoline- 2,3-dione with amino acids (tryptophan, alanine and valine) were synthesized and characterized by elemental analysis, IR, electronic spectra, conductance measurements, and biological activity. The analytical data showed that the Schiff base ligand acts as bidentate towards metal ions via the azomethine nitrogen and carboxylate oxygen by a stoichiometric reaction of M:L (1:2) to form metal complexes. NMR (1H, 13C and 119Sn) spectral data of the ligands and metal complex agree with proposed structures. The conductivity values between 14 - 27 ohm-1cm2mol-1 in DMF imply the presence of non-electrolyte species. 3D molecular modeling and analysis of bond lengths and bond angles have also been conducted for a representative compound, [Bu2Sn(L2)2], to substantiate the proposed structures. Antibacterial results indicate that the metal complexes are more active than the free ligands.

A Graphene-Based Aerogel Was Prepared as Solid Adsorbent for the Enrichment of Platinum (IV) at Trace Concentration

A three-dimensional graphene-based composite was prepared by a simple one-step in-site reduced-oxide method under atmospheric pressure. The obtained hydrogel was modified with 4-amino-benzenesulfonic acid and connected with ethylenediamine, and freeze-dried into an aerogel, which was characterized. Then the surface interaction with platinum (Pt, IV) was explored. The obtained aerogel showed good adsorption for Pt (IV) at acid conditions, giving a rising to the adsorption rate > 98% while pH ≥ 6. Using hexadecyl trimethyl ammonium bromide of 2% (m/V) as an eluent to desorb the Pt (IV) from the surface of the aerogel, a desorption rate of 81.1% was obtained in this process. Urea, buffer aquation and other surfactants were used in the desorption experiment to understand the adsorption mechanism between the aerogel and Pt (IV). In this work, hydrogen bond, van der Waals force and electronic interaction force mainly drove the adsorption process. For obtaining more purified Pt (IV), we used 0.5% CTAB to desorb Pd (II). A new three-dimensional graphene-based composite was prepared and the surface interaction between Pt (IV) and composite was experimented for understanding the adsorption mechanism and exploring its potential application in sample preparation in low concentration.

Quantum-Chemical Interpretation of the Spectroscopy of Highly Luminescent 1,3,5-Triazapentadiene Complexes of Platinum（Ⅱ）

The quantum-chemical calculations were performed to determine the nature of the equilibrium geometry of the ground and excited states of the 1,3,5-triazapentadiene complexes of platinum（Ⅱ） and theirs nature and structure of molecular orbitals.

New Square-Pyramidal Oxovanadium (IV) Complexes Derived from Polydentate Ligand (L1)

New series of oxovanadium (IV) complexes isolated from 2,4,6-tris-(2-pyridyl)-1,3,5-triazine (L1) are incorporated and portrayed using spectroscopic (IR, UV-Vis, ESR, mass spectrometric), magnetic moment, thermal and cyclic voltammetry measurements. The results demonstrate that L1 acts in various styles of chelation with [V3O3(L1)(SO4)3(EtOH)1/2(H2O)3/2] 1), [VO(L1)(2,4-pentadionate)]·Cl·4HCl 2), [V2O2(L1)(SO4)2(EtOH)5/2] 3), [V2O2(L1)(SO4)2(EtOH)3/2(H2O)1/2] 4), [VO(L1)SO4 (H2O)3/2]·2.5H2O 5) and [V2O2(L1)(SO4)2(H2O)]·H2O 6). The values of magnetic moments and spectral studies suggest a square-pyramidal geometry around the V (IV) ion for all complexes. The molar conductance values suggest that the complexes are non-electrolyte, except the [VO(L1) (2,4-pentadionate)] Cl·4HCl. Molecular modeling calculates the bond length, bond angle, chemical reactivity, energy components (Kcal/mol) and binding energy (Kcal/mol) for the isolated complexes. The in vitro antibacterial studies of these complexes screened against pathogenic bacteria prove them as growth inhibiting agents. Antitumor activity is carried out in vitro on human mammary gland (breast) MCF-7 and cervical cancer cell-HeLa has shown that [VO(L1)SO4(H2O)3/2]·2.5 H2O and [VO(L1)(2,4-pentadionate)] Cl·4HCl complexes display the highest powerful activity between all of the investigated complexes.

SYNTHESIS AND CATALYTIC ACTIVITY OF PLATINUM COMPLEX OF ACRYLATE TERPOLYMER WITH Se, N BIDENTATE LIGAND

Acrylate terpolymer- bound Se, N bidentate ligand was synthesized fromthe side chain chlorine of copolymer and β- dimethylamino -β - hydroxyl diethyl selenoether. The polymer - supported platinum complex exhibited highcatalytic activity in the hodrosilylation of olefins with triethoxysilane.

Se(IV)在北山花岗岩上的吸附

采用批式法研究了粉碎的甘肃北山花岗岩样品(BS03, 600 m)对Se(IV)的吸附作用. 实验结果表明: 在pH 3-7范围内, Se(IV)的吸附分配比(Kd)基本不随pH变化; 当pH > 7时, Se(IV)在北山花岗岩上的Kd随pH的增大而减小. Se(IV)在北山花岗岩上的吸附不随离子强度变化. 北山地下水条件下的Ca2+(4.10×10-3 mo·lL-1)和SO42- (3.17×10-3 mo·lL-1)对Se(IV)的吸附没有影响. 此外, Se(IV)/Eu(III)/北山花岗岩三元吸附体系的实验结果表明, Se(IV) (1.46×10-5 mo·lL-1)和Eu(III) (3.33×10-6 mo·lL-1)在北山花岗岩上的吸附作用相互之间没有表观影响. 通过假定HSeO3-在广义的吸附位点≡SOH上发生了生成≡SHSeO3和≡SSeO3-的两个表面配位反应, 定量解释了Se(IV)的吸附实验结果.

八种稀土金属配合物和铂配合物抗HIV活性的研究

为了寻找治疗艾滋病的新药,研究了8种稀土金属(镧、铒、镝、钆、镨、镱、钐、钕)配合物和铂配合物的抗HIV活性。我们以C8166细胞系为指示细胞,测定样品对HIV-1IIIB诱导的细胞合胞体形成的抑制作用,并以MTT方法测定它们对细胞存活率的影响,以研究稀土和铂配合物对细胞的毒性。根据公式,计算出其CC50和EC50值,并进一步计算出其TI值。结果表明,镧配合物、钐配合物和铂配合物的EC50值分别为0.006μg/ml、74.28μg/ml和21.54μg/ml,它们的治疗指数分别为63、21和45,具有一定的抗HIV-1活性。其它的配合物具有很低或者不具有抗HIV-1活性。