Synthesis,molecular, crystal and electronic structure of [RuCl2(PPh3)2(C3N2H4)2]

The reaction of [RuCl₂(PPh₃)₃] complex with pyrazole has been examined. A new ruthenium complex – [RuCl₂(PPh₃)₂(C₃N₂H₄)₂] has been obtained and characterised by IR and UV–Vis measurements. Crystal and molecular structure of the complex has been determined.     

Synthesis,characterization and crystal structure of bis(acetylacetonato)dimethanolnickel(II): [Ni(acac)2(MeOH)2]

Bis(acetylacetonato)dimethanolnickel(II) was isolated as turquoise needle-like crystals by recrystallization of bis(acetylacetonato)nickel(II) from methanol solution and fully characterized by ¹H and ¹³C NMR, FT-IR spectroscopy, and single crystal X-ray diffraction. The X-ray structure analysis gives essentially a triclinic unit cell of bis(acetylacetonato)dimethanolnickel(II) containing one centrosymmetric molecule of the formula Ni[(O₂C₅H₇)₂(OHCH₃)₂]. The Ni(II) ion is located at the inversion centre of a tetragonally distorted octahedral coordination sphere. The equatorial plane of the tetragonally distorted octahedral coordination sphere includes four O-donor atoms of two acetylacetonato ligands and the axial positions are occupied by two oxygen atoms of two methanol ligands.     

Synthesis and Characterization of Poly[bis(3-aminophenyl) diselenide] and Poly[bis(3-aminophenyl) diselenide-co-aniline]

Summary Bis(m-aminophenyl)diselenide was synthesized by diazotation of m-nitroaniline followed by incorporation of potassium selenium cyanate, and the reduction of the nitro groups by addition of tin and concentrated HCl. This dihydrochloride monomer was polymerised using ammonium persulphate in 0.25 M HCl as oxidizing agent. Copolymers of aniline with bis(m-aminophenyl)diselenide were prepared by oxidation of diselenide and aniline mixtures, at several mole ratios of aniline in the feed (f₁), with the same oxidizing agent. In the all the range of polymers analysed there are more diselenide comonomer units than aniline units. The polymer and copolymers were characterized by FTIR, elemental analysis, thermal stability and electrical conductivity, showing a high thermal stability, with a weight loss of 10% at 400 °C and there is an important effect of groups diselenide on the electrical properties, because conductivities are highly modified when the substitution is in m-position in the aniline ring. Therefore, it is necessary to add a high mole ratio of aniline in the feed to obtain copolymers with conductivities within the semi-conduction range.     

Synthesis,crystal structures and spectral characterization of trans-bisaquabis(o-vanillinato)copper(II), cis-aquabis(o-vanillinato)copper(II) and aqua[bis(o-vanillinato)-1,2-ethylenediimin]copper(II)

trans-Bisaquabis(o-vanillinato)copper(II) (I), cis-aquabis(o-vanillinato)copper(II) (II) and aqua[bis(o-vanillinato)-1,2-ethylenediimin]copper(II) (III) complexes were synthesized and characterized by means of elemental analysis, IR and UV–vis spectroscopy, thermal analysis and X-ray diffraction techniques. The coordination geometry around Cu(II) is a octahedral with coordination number of six for I and is a square-pyramidal with coordination number of five for both II and III. In all three compounds, a three-dimensional structure is formed via C–H⋯O hydrogen-bond interactions and intermolecular π–π and π-ring interactions. The compounds I and III have two-dimensional hydrogen-bonded step-chain structure in xz-plane, while compound II has a zigzag chain structure in xy-plane. On the basis of the first DTA_max of the anhydrous complexes of I and II, the thermal stability sequence is trans-isomer > cis-isomer. This fact should be related with the binding of the ligand.     

Structural correlations in nickel(II)–thiodiacetato complexes: molecular and crystal structures and properties of [Ni(tda)(H2O)3]

Triaqua(thiodiacetato)nickel(II) has been synthesized and studied by X-ray crystallography, thermal, spectral and magnetic methods. The compound crystallizes in the triclinic system, space group , in contrast to the related compound [Ni(tda)(H₂O)₃] · H₂O (orthorhombic) reported long time ago. As in other four Ni–tda derivatives, the metal atom exhibits an octahedral coordination and tda ligand adopts a fac-tridentate chelating role. The studied compound is closely related to [Zn(tda)(H₂O)₃]. In addition, a structural comparison of the binary and ternary Ni–tda derivatives reveals that auxiliary N-donor ligands bind the metal atom using the trans-positions towards the Ni–O(carboxylato) bonds, but not in trans to the Ni–S(thioether) bond.     

The synthesis,spectroscopic investigation,crystal and molecular structure of the [ReBrCl2(SbPh3)3] complex

The [ReBrCl₂(SbPh₃)₃] complex has been obtained in the reaction of [Bu^t₄N]₂[ReBr₃Cl₂(NO)] with an excess of triphenylstibine. The halide ions and stibine molecules of [ReBrCl₂(SbPh₃)₃] are arranged in a meridional fashion. The substitution reactions of the nitrosyl ligand are very rare so the formation of the [ReBrCl₂(SbPh₃)₃] compound in this reaction is particularly interesting.     

Photoluminescence and photochemistry of Pt(II)(PPh3)2(C6O6) induced by rhodizonate IL excitation

The complex Pt(II)(PPh₃)₂(C₆O₆) was prepared by the reaction of Ag₂C₆O₆ with cis-Pt(PPh₃)₂Cl₂ in acetonitrile. Pt(PPh₃)₂(C₆O₆) is characterized by a lowest-energy IL (rhodizonate) excited state. The complex shows an IL fluorescence, but is also photoactive. The photolysis leads to the conversion of rhodizonate to croconate in the coordinated state: Pt(II)(PPh₃)₂(C₆O₆) → Pt(II)(PPh₃)₂(C₅O₅) + CO.     

Synthesis,crystal structures and properties of two Pd(II) and Pt(II) complexes involving 3,5-diphenylpyrazole and NO2 donor ligands

A pyrazolate bridged binuclear Pd(II) complex [Pd₂(μ-dppz)₂(Hida)₂] · CH₃OH · 2H₂O (1) (dppz = 3,5-diphenylpyrazolate) with monoprotonated iminodiacetate (Hida) and a mononuclear Pt(II) complex containing Hdppz and 2,6-pyridinedicarboxylate (2,6-dipic) [Pt(Hdppz)(2,6-dipic)] · CH₃OH (2) have been synthesized and characterized by elemental analysis, ¹H NMR, ESI-MS and single crystal X-ray diffraction studies. The molecular packing for 1 shows a 2D network while that for 2 constitutes a left-handed 1D helix. Moderate luminescence property and antimicrobial activity against Bacillus subtilis have been noted for both.     

Second-sphere Coordination of [Pt(bipy)(NH3)2]2+ by Dibenzo-crown Ethers. Solution Spectroscopic Studies and the Crystal and Molecular Structures of [Pt(bipy)(NH3)2.dibenzo-30-crown-10] [PF6]2.0.6 H2O and [Pt(bipy)(NH3)2.dibenzo-24-crown-8] [PF6]2

In addition to hydrogen bonding and Coulombic forces, charge transfer interactions stabilise the 1:1 adducts formed between [Pt(bipy)(NH₃)₂] ²⁺ and a series of dibenzo-3n-crown-n (n = 6–12) ethers as evidenced by ¹H NMR and UV-visible spectra in solution and by X-ray crystal structures (for n = 8 and 10) in the solid state. Mutual diamagnetic (ring current) shielding by the aromatic systems of host and guest results in dramatic upfield shifts of certain aromatic proton resonances on adduct formation, especially when n = 10 or 11. A broad charge-transfer absorption band at 350 nm attains its maximum intensity at n = 11 though stability constant measurements indicate optimum binding when n = 10. X-ray diffraction studies reveal that, when n = 8, only one of the crown ether benzo-rings interacts with the bipyridyl ligand in a charge-transfer sense. However, when n = 10, the macrocycle is sufficiently large and flexible to allow both benzo-rings to enter into stabilising interactions with the bipyridyl ligand such that the platinum complex is encapsulated by the host in a U-shaped cavity.     

Investigations of the Binding of [Pt2(DTBPA)Cl2](II) and [Pt2(TPXA)Cl2](II) to DNA via Various Cross-Linking Modes

We have constructed models for a series of platinum-DNA adducts that represent the binding of two agents, [Pt₂(DTBPA)Cl₂](II) and [Pt₂(TPXA)Cl₂](II), to DNA via inter- and intra-strand cross-linking, and carried out molecular dynamics simulations and DNA conformational dynamics calculations. The effects of trans- and cis-configurations of the centers of these di-nuclear platinum agents, and of different bridging linkers, have been investigated on the conformational distortions of platinum-DNA adducts formed via inter- and intra-strand cross-links. The results demonstrate that the DNA conformational distortions for the various platinum-DNA adducts with differing cross-linking modes are greatly influenced by the difference between the platinum-platinum distance for the platinum agent and the platinum-bound N7–N7 distance for the DNA molecule, and by the flexibility of the bridging linkers in the platinum agent. However, the effects of trans/cis-configurations of the platinum-centers on the DNA conformational distortions in the platinum-DNA adducts depend on the inter- and intra-strand cross-linking modes. In addition, we discuss the relevance of DNA base motions, including opening, shift and roll, to the changes in the parameters of the DNA major and minor grooves caused by binding of the platinum agent.     

[Ag2(aca)2]n and [Ag4(aca)4(NH3)2] (acaH = 9-anthracenecarboxylic acid): Synthesis,X-ray crystal structures,antimicrobial and anti-cancer activities

[Ag₂(9-aca)₂]_n and [Ag₄(9-aca)₄(NH₃)₂] (9-acaH = 9-anthracenecarboxylic acid) have been prepared and structurally characterized. [Ag₂(9-aca)₂]_n consists of polymeric ribbons of linked disilver(I) syn–syn bridged dicarboxylate units. [Ag₄(9-aca)₄(NH₃)₂] is tetrameric and centrosymmetric, with two syn–syn bridging carboxylates linked to the bimetallic Ag–Ag core and a further two syn–anti bridged carboxylate ligands in the equatorial plane, being coordinated to one Ag in the bimetallic core and to a second Ag, with the latter also bonded to an NH₃ ligand. In vitro studies show that both complexes are extremely cytotoxic against selected human fungal and bacterial pathogens, and each complex also greatly inhibits the growth of two mammalian cancer cell lines.     

Unexpected formation of dihaloplatinum(II) and platinum(IV) complexes in the reaction of [PtMe2(bu2bpy)] with 1,2-dibromotetrachloroethane: Crystal structure of trans-[PtMe2BrCl(bu2bpy)]

The platinum(II) complex [PtMe₂(bu₂bpy)] (bu₂bpy = 4,4′-di-tert-butyl-2,2′-bipyridine) (1) reacted with 1,2-dibromotetrachloroethane in a 2:1 mole ratio of Pt(II): (CBrCl₂)₂ to afford trans-[PtMe₂BrCl(bu₂bpy)] (2) and [PtCl₂(bu₂bpy)] (3). The ¹H NMR spectroscopy shows that the Pt–Me bond cleavage is mainly involved after a fast oxidative addition reaction. Complex trans-[PtMe₂BrCl(bu₂bpy)] (2) has been characterized by X-ray diffraction which shows that platinum adopts an octahedral geometry.     

液晶材料反-4-[反-4-(3,4,5-三氟苯基)环己基]环己基-1-乙烯的合成

以3,4,5-三氟溴苯和单乙二醇缩4,4'-双环已基二酮为起始原料,经格氏反应、脱水、氢化、脱保、转型、Wittig反应、水解、转型和Wittig反应最终合成了标题化合物.其中酮的转型反应中选取20%(m(AlCl3)/m(顺式))量的AlCl3,反应时间1.5 h;脱水反应最佳溶剂选二甲苯,反应时间4 h.纯化后目标...     

Spontaneous magnetization in [1-(4-cyanobenzyl)pyridinium][Pt(mnt)2]: synthesis,crystal structure and magnetic property

A new complex [1-(4-cyanobenzyl)pyridinium][Pt(mnt)₂] (1), in which mnt²⁻ = maleonitriledithiolate, has been prepared and characterized. In the solid state, anions and cations of 1 form completely segregated stacking column, and the [Pt(mnt)₂]⁻ anion column behaves as one-dimensional (1-D) spaced magnetic chains. 1 spontaneously magnetizes at low temperature, which may arises from spin canting.     

Synthesis and structure of vaulted trans-Bis[1-(2-phenoxy)-imidazol-2-ylidene-C2,O]platinum(II) complex

trans-Bis[1-(2-phenoxy)-imidazol-2-ylidene-C²,O]platinum(II) complex bearing a dodecamethylene bridge (1) was synthesized and characterized by ¹H, ¹³C NMR, COSY, NOESY, FT-IR, high-resolution mass spectroscopy, and single crystal X-ray diffraction. X-ray and 2D-NMR analyses revealed that complex 1 has a characteristic syn-conformation in both the solid and solution states, where cofacial phenoxy-NHC ligands are folded and fixed under strong restriction by the vaulted structure. A crystal of 1 obtained from EtOH exhibits weak blue phosphorescence under UV excitation at 320 nm.     

Facile synthesis and characterization of novel bis(2-S-alkylpyridines) and bis(3-aminothieno[2,3-b]pyridines) incorporating 1,3-diarylpyrazole moiety

3-(4-Hydroxyphenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde (1) is condensed with acetophenone to afford the corresponding unsaturated carbonyl compound 4 whose potassium salt is reacted with 1,4-dibromobutane to afford the bis-unsaturated carbonyl compound 3. Both carbonyl compounds 3 and 4 are reacted with 2-cyanoethanethioamide, through Michael addition reaction followed by cyclocondensation, to prepare the starting materials bis(pyridine-2(1H)-thione) derivative 5 and pyridine-2(1H)-thione derivative 8. Two synthetic routes to synthesize the target materials 7 and 14 are described to get the most efficient method for preparation and maximum yield%. The first route came from the direct alkylation of the bis(pyridine-2(1H)-thione) derivative 5 using iodomethane (6a) and benzyl chloride (6b) to afford the corresponding bis(2-S-alkylpyridine) derivatives 7a,b. The reaction of 5 with halo-containing compounds 10a–d to synthesize the target materials bis(3-aminothieno[2,3-b]pyridine) derivatives 14a–d failed under various reaction conditions. The second route involves the reaction of pyridine-2(1H)-thione derivative 8 with 6a,b and 10a–d to afford the corresponding 2-S-alkylpyridine derivatives 9a,b and 3-aminothieno[2,3-b]pyridine derivatives 13a–d, through the formation of 2-S-alkylpyridine derivatives 12a–d followed by a Thrope-Ziegler reaction, whose potassium salts reacted with 1,4-dibromobutane to afford the corresponding target materials 7a,b and 14a–d, respectively. The structures of target molecules were elucidated using elemental analyses and spectral data.     

Synthesis and crystal structure of mer-nitroaquatriamminenitrosylruthenium(II) nitrate [RuNO(NH3)3(NO2)(H2O)](NO3)2

The reaction between mer-[RuNO(NH₃)₃(NO₂)(OH)]Cl·0.5H₂O and an excess of 16 M HNO₃ leads to the protonation of the starting complex and crystallization of the complex with a coordinated water molecule and nitrite anion. The crystal structure of the product has been determined. The coordinated water molecule tends to be a weak acid with a measured pK_a of 2.4.     

Novel Zinc(II) Complexes [Zn(atc-Et)2] and [Zn(atc-Ph)2]: In Vitro and in Vivo Antiproliferative Studies

Cisplatin and its derivatives are the main metallodrugs used in cancer therapy. However, low selectivity, toxicity and drug resistance are associated with their use. The zinc(II) (Zn^II) thiosemicarbazone complexes [Zn(atc-Et)₂] (1) and [Zn(atc-Ph)₂] (2) (atc-R: monovalent anion of 2-acetylpyridine N4-R-thiosemicarbazone) were synthesized and fully characterized in the solid state and in solution via elemental analysis, Fourier transform infrared (FTIR), ultraviolet-visible (UV-Vis) and proton nuclear magnetic resonance (¹H NMR) spectroscopy, conductometry and single-crystal X-ray diffraction. The cytotoxicity of these complexes was evaluated in the HepG2, HeLa, MDA-MB-231, K-562, DU 145 and MRC-5 cancer cell lines. The strongest antiproliferative results were observed in MDA-MB-231 and HepG2 cells, in which these complexes displayed significant selective toxicity (3.1 and 3.6, respectively) compared with their effects on normal MRC-5 cells. In vivo studies were performed using an alternative model (Artemia salina L.) to assure the safety of these complexes, and the results were confirmed using a conventional model (BALB/c mice). Finally, tests of oral bioavailability showed maximum plasma concentrations of 3029.50 µg/L and 1191.95 µg/L for complexes 1 and 2, respectively. According to all obtained results, both compounds could be considered as prospective antiproliferative agents that warrant further research.     

Synthesis and cytotoxicity of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes

A series of leaving group derivatives of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes were synthesized and tested for cytotoxicity. The enantiomeric purity was determined by 1H NMR spectroscopy on the final diamines after derivation with (1R)-myrtenal. For coordination to platinum, the diamines were reacted with K2PtI4. The treatment of diiodoplatinum(II) complexes (4F-Ph/iProp-PtI2) with Ag2SO4 resulted in the sulfatoplatinum(II) complexes (4F-Ph/iProp-PtSO4), which can be easily transformed to dichloroplatinum(II) complexes (4F-Ph/iProp-PtCl2) with 2 n HCl. The importance of the leaving groups and the configuration at the diamine ligand on the antiproliferative effects was evaluated on the hormone-dependent MCF-7 and the hormone-independent MDA-MB 231 breast cancer cell lines as well as the LNCaP/FGC prostate cancer cell line. (R,R)-4F-Ph/iProp-PtCl2 was identified as the most active platinum(II) complex. The 3-methyl group increased antiproliferative effects relative to the [1,2-diamino-1-(4-fluorophenyl)butane]platinum(II) complexes described in an earlier study.