bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and biological activity of new heterocyclic compounds 5‐[(1,l‐dimethyl)ethyl]‐3‐aryl‐(1H‐1,2,3‐triazol‐1‐yl)‐5‐isoxazolidinols
Authors: Guo‐Feng Zhao , Gui‐Yu Jin , Zhong‐Fa Liu , Jun Ren , Yu‐Chang Li
Published: September 2010

In this paper new heterocyclic compounds 5‐[(1,1‐dimethyl)ethyl]‐3‐aryl‐(1H‐l,2,3‐triazol‐1‐yl)‐5‐isoxazolodinols were obtained by the reaction of vinyl triazole derivatives with hydroxylamine hydrochloride under the action of sodium carbonate. The biological tests indicate that they had plant‐growth regulating activity.
Synthesis, halogenation and structural characterization of (Z)‐1‐[2‐(triphenylstannyl)vinyl]‐1‐cyclododecanol
Authors: Kuit Huang , Fang‐Xin Fu , Hua‐De Pan
Published: September 2010

Synthesis and characterisation of (Z)‐1‐[2(triphenylstannyl)vinyl]‐l‐cyclododecanol, c‐(CH2)11C(OH)CH=CHSnPh3, are reported, together with its halogenation by I2, Br2 and ICI to yield derivatives of the types c‐(CH2)11C(OH)CH=CHSnPhs−nXn (n=1, 2; X=I, Br, Cl, respectively). The molecular structures of two compounds have been determined by X‐ray diffraction analysis. The tin atom exhibits a distorted tetrahedral geometry in the crystal of (Z)‐l‐[2–(triphenylstannyI)vinyl]‐l‐cyclododecanol, but a trigonal bipyramidal geometry in the monoiodo‐derivative (Z)‐l‐[2]‐(diphenyliodo‐stannyl)vinyl)‐1‐cyclododecanol and other derivatives, in which significant intramolecular coordinative interaction HO→Sn ia observed. And the formation of a five‐membered tin containing ring is significant for their antitumour activities.
Synthesis of a novel cyclodextrin dimer linked by a macrocyclic polyamine
Authors: Yong Liu , Guo‐Ping Xue , Cheng‐Tai Wu
Published: September 2010

The first example of cyclodextrin dimer appending a macrocyclic polyamine spacer on the primary faces was synthesized via two approaches: 1, a direct reaction of 1,7‐bis(2′‐aminoethyl)‐4,10‐dimethyl‐1,4,7,10‐tetraazacyclododecane (1) with an excess of 6‐deoxy‐6‐O‐tosyl‐β‐cyclodextrin; 2, a condensation of 1 with two equivalents of 6‐deoxy‐6‐formyl‐β‐cyclodextrin, which wan followed by a reduction with NaBH4.
EPR Study on the complex formed by charge‐transfer process between ground‐state acceptor chloranil and nine donors
Authors: Ji‐Liang Shi , Cheng‐Ming Zhou , Hu‐Nan Yi , Zhi‐Hai Qiu , Yao‐Hong Fu , Xi‐Kui Jiang
Published: September 2010

EPR study showed that the semi‐quinone radical anion of chloranil (TCQ) was formed in a charge‐transfer process between ground state chloranil as acceptor and each one of the following ground state donors, i.e., N, N‐diethyl aniline (DEA), phenothiazine (PTZ), carbazole (CBZ), pyrene (PY), ferrocene (FRO), triphenylphosphine (TPP), triethylamine (TEA), anthracene (AN) and N, N‐diethyl‐3‐aminophenyl ester of palmitic acid (DPP). Our results indicate that there is a tunneling effect for the ground‐state charge‐transfer process between chloranil and the donor.
Aggregation of deuteroporphyrin IX diesters in aqueous‐organic binary solution
Authors: Guo‐Zhen Ji , Hui Hu , Guang‐Min Zhang , Wei‐Min Fu , Dao‐Dao Zhang
Published: September 2010

The aggregation properties of a series of deuteroporphyrin IX diesters in the THF‐Buffer (0.1 mol·L−l Tris‐HCl) aquiorgano solvent have been studied by means of UV‐Vis and fluorescence spectrometers. Experimental data show that the dimerization of porphyrins is mainly determined by π‐π interaction in pure organic solution while further aggregation of porphyrins with long hydro‐carbon chains is more likely driven by hydrophobic‐lipophilic interaction in aqueous‐organic binary solution. The appearance of the aggregates induces a red shift in absorption spectra and fluorescence quenching in fluorescence spectra. The chain‐length effect and chain‐foldability effect have also been observed.
Photocatalytic decomposition of oil films floating on water using TiO2 supported on hollow glass microbeads by sunlight
Authors: Shi‐Fu Chen , Xue‐Li Cheng
Published: September 2010

The feasibility of photocatalytic decomposition of oil films floating on water using TiO2 supported on hollow glass microbeads was studied. The results showed that 100% of ethylbenzene and 78% of dodecane can be photocatalytically removed after 8 h illumination with sunlight. The TiO2 supported on the hollow glass microbeads was not easily detached from the beads. After 150 h illumination there was no significant loss of the photocatalytic activity of TiO2. Some intermediate products of photocatalytic decomposition of dodecane were detected.
EXAFS and FTIR structural characterization for the crystal of monomeric tetraphenylporphyrinato gadolinium: [Gd(TPP)acac·8H2O·3TCB]
Authors: Jian‐Zhuang Jiang , Tian‐Dou Hu , Jing‐Lei Xie , Ce Li , Jing‐Zhi Zhang
Published: September 2010

The coordination number of the gadolinium atom and bond distances in the crystal of monomeric porphyrinate, [Gd(TPP)acac·8H2O·3TCB] (TCB: 1,2,4‐trichlorobenzene, acac: anion of acetylacetone), were determined by EXAFS method. The Gd atom is eight‐coordinated to the four nitrogen atoms of a tetraphenylporphyrin ring, to the two oxygen atoms of one acetylacetonato anion and to two water molecules with Gd—N=0.232 nm, Gd—O=0.243 nm.
Synthesis of novel N‐aminoethyl cyclic polyamines
Authors: Yong Liu , Guo‐Ping Xue , Cheng‐Tai Wu
Published: September 2010

Two novel cyclic polyamine derivatives bearing double aminoethyl groups have been synthesized. The synthetic intermediate, N‐p‐toluenesulfonyl‐aziridine, was prepared employing an improved procedure.
Synthesis and photoreaction of polymethylenediamine bis(4‐methyl‐7‐coumarinyl)oxyacetic amides
Authors: Da‐Ming Du , Ling‐Ping Zhou , Yong‐Mei Wang , Ji‐Ben Meng
Published: September 2010

A series of polymethylenediamine bis(4‐methyl‐7‐coumarinyl)oxyacetic amides have been synthesized and their intramolecular photochemical cyclodimerizations have been investigated. It was found that only syn‐HT configuration products were obtained when these bisamides were directly irradiated in dimethyl sulfoxide solution and the yields of the products decreased with the increase of the chain length. The structures of long chain amides and their intramolecular photocyclization products were determined by IR, MS, 1H NMR and elemental analysis.
Synthesis and fluorescent properties of bis‐salicyloyl hydrazide metal complexes of some group IV ions
Authors: Dong‐Dong Mn , Jian‐Feng Zhai , Zhi‐Wen Wang , Yu‐Quan Shen
Published: September 2010

Four novel organometallic compounds containing tin(IV), titanium(IV) and zirconium (IV) ions were synthesized and strong fluorescent emission was observed from two tin(IV) complexes.
Photoinduced energy transfer and charge transfer on squarylium cyanine dyes
Authors: Wei Zhao , Bao‐Wen Zhang , Yuan‐Jun Hou , Yi Cao
Published: September 2010

A series of squarylium cyanine dyes (Sqs) were synthesised to explore their applications in functional devices. Preliminary investigation on the mechanism involved in these devices was carried out. Spectroscopic behavior of Sqs with porphyrin (P), 8‐hydroxyquinolium aluminum (Alq) and ruthenium bipyridyl complex (Ru(bipy)) in solution, in film and on nanocrystalline TiO2 was investigated, respectively. A mechanism including photoinduced energy transfer and charge transfer processes was suggested in the corresponding practical devices. By means of doping, a red organic electroluminescent device (ELD) using Sq‐doped Alq as the emission layer (EML) has been developed, and the total light to electricity efficiency of nanocrystalline TiO2 electrode based on using Sq‐doped Ru(bipy) M photosensitizer has been improved greatly in the whole visible region, particularly in the red area above 600 nm.
Coupling matrix element of electron self‐exchange reactions in solution
Authors: Yu‐Xiang Bu , Cheng‐Bu Liu , Cong‐Hao Deng
Published: September 2010

On the basis of the common feature among the electron transfer process and the ion hydration process as well as the relevant experimental kinetic data of electron trader reaction, a new accurate hydration potential function scheme for the determination of electron transfer coupling matrix element is presented. The coupling matrix element between two hydrated ions of the reacting system in solution is calculated. The results and the applicability of this scheme are discussed.
A novel synthesis of coumarin derivatives
Authors: Mohey El‐Deen, Ibrahim
Published: September 2010

The chemical. behaviors of 3‐ethynylcoumarin towards benzyl bromide, diazonium chloride, hydrogen chloride, ethyl magnesium bromide and its self‐coupling are reported.
Synthesis of porphyrin nitrogen mustards with potential anti‐tumor activities in chemotherapy and photodynamic therapy
Authors: Zhi‐Long Chen , Jing‐Rong Chen , Wei‐Qin Wan , De‐Yu Xu
Published: September 2010

2,7,12,18‐Tetramethyl‐13,17‐di[3′‐N, N‐di(2″‐chloroethyl)aminopropyl]porphin and its 3,8‐di(1′‐alkyloxyethyl)‐analogous or porphyrin‐nitrogen mustards were synthesized for the first time. Their structures were determined by spectroscopies and elemental analyses. Most of the compounds possess both the chemotherapeutic and photodynamic effects on tumor and deserve further investigation.
Samarium diiodide induced asymmetric synthesis of γ‐butyrolactone using chiral auxiliaries derived from isosorbide and isomannide
Authors: Ming‐Hua Xu , Gue‐Qiang Lin , Li‐Jun Xia
Published: September 2010

The asymmetric reductive coupling reaction of various acrylates derived from D‐isosorbide and D‐isomannide with acetophenone mediated by samarium diiodide to give both enantiomers of the optically active γ‐butyrolactone was described. The best enantiomeric excess of the products was 60%.
Synthesis and ferromagnetic interaction in oxamido‐bridged heterodinuclear copper(II)‐chromium (III) complexes
Authors: Li Yan‐Tuan , Yan Cui‐Wei , Liao Dai‐Zheng
Published: September 2010

Four μ‐ oxamido heterodinuclear complexes, [Cu (oxae) Cr (L)2 ] (NO3) 3, where oxae denotes the N, N'bis (2‐aminoethyl) oxamido dianion and L represents 1,10‐phenanthroline (phen); 5‐nitro‐1,10‐phenanthroline (NO2‐phen); 5‐methyl‐1, 10‐phenanthroline (Me‐phen) and 2, 2′‐bipyridine (bpy), have been synthesized and characterized by elemental analyses, magnetic moments (at room temperature) and molar conductivity measurements and spectroscopy. It is proposed that these complexes have extended oxamido‐bridged structures consisting of a copper (II) ion and a chromium (III) ion, which have a square planar environment and octahedral environment, respectively. The cryomagnetic properties of the [Cu(oxae)Cr(bpy)2(NO3)3(1) and [Cu(oxae)Cr(phen)2](NO3)3(2) complexes have been measured over the range of 4.2–300 K. The leastsquares fit of the experimental data based on the spin Hamiltonian, Ĥ = ‐ 2JŜ1·Ŝ2, the exchange integrals (J) were evaluated as +36.9 cm−1 for 1 and +35.8 cm−1 for 2. The reds have connived that the spin coupling between the adjacent copper (II) and chromium (III) ions through oxamido‐bridge in both 1 and 2 is ferromagnetic.
Synthesis and crystal structure of dinuclear nickel (II) complex
Authors: Liu Sheng‐Hua , Chen Liao‐Rong , Fu En‐Qin , Wu Cheng‐Tai
Published: September 2010

The crystal structure of Ni (II) complex with 3‐hydroxyl‐1,5‐diazacycloheptane‐N, N′‐diacetate was determined by X‐ray diffraction method. Crystal data for Ni2 (C9H14 N2O5 )2·2H2O: monoclinic, space group P21/n, a =1.1717(5), b =0.9794(3), c = 1. 2971(2) nm, β=96.62(3), V = 1. 4786(7) nm3, Dc = 1. 377 g/cm3, Z = 2, μ =13.321 cm−1 (Mo‐Ka), F (000) = 640. The final R and Rω are 0.075 and 0.089 respectively. The Ni(II) ion forms 2:2 complex with ligand. Two ligands are bridged by two Ni(II) atoms which are bridged by two 0 atom. Every Ni(II) is coordinated by two N atoms and four O atoms The coordination polyhedron of the Ni(II) ion is a distorted octahedron.
Rational synthesis structural characterization and the third‐order nonlinear optical properties of two new M‐Cu‐S (M = Mo or W) clusters
Authors: Yu Rong‐Min , Lu Shao‐Fang , Chen Hong‐Bing , Huang Xiao‐Ying , Huang Jian‐Quan , Wu Bo‐Chang , Si Jin‐Hai
Published: September 2010

By the additional reaction of binuclear compounds (Me4N)2M2S4 (TDT)2 (M = Mo, W; H2TDT= H2CH3GH3S2) with mononuclear cuprous complex, two new M‐Cu‐S clusters Mo2 Cu2 S4 (TDT)2‐(PPh3)2CH3CH2OH (1) and W2Cu2S4 (TDT)2 (PPh3 )2 · 0. 5CH3 CH2 OH·0. 5H2O (2) have been prepared and characterized by IR, UV‐Vis, 31P NMR spectroscopy, cyclic voltammetry and single crystal X‐ray structure analysis. Both compounds crystallize in space group P 21/ n with lattice parameters a = 1.0956(3), b = 2. 2072(3), c =2.4340(3) nm, β=100.36(2)°, V= 5.790(3) nm3 and Z = 4 for 1 and a = 1.0965(9), b = 2.2135(3), c = 2.4317(4) nm, β = 99. 63(8)°, V = 5.819(8) nm3 and Z = 4 for 2. Both molecular structures contain a cubane‐like cluster core [M2Cu2S4] (M= Mo, W) and their skeletons are almost the same except for M atoms. The syntheses, structures and spectrum characterizations of these two clusters are discussed. The third‐order nonlinear optical (NLO) property of the two clusters was studied by the technique of forward degenerate four‐wave mixing (DFWM) for the first time and these clusters exhibited relatively large nonlinear optical coefficients.
Trans‐cis isomerization of 4‐(2‐(9‐anthryl)vinyl)pyridine. Molecular structures and 1H NMR kinetic studies
Authors: Choi Ya‐Yin , Wong Wai‐Yeung , Wong Wing‐Tak
Published: September 2010

Both cis‐ and trans‐isomers of 4‐(2‐(9‐anthryl) vinyl) pyridine were isolated and their molecular structures established by X‐ray crystallographic method. Variable temperature 1H NMR spectroscopy was used to study the trans to cis isomerization of the title compound. The kinetic study of the reaction was based on the ratio of the NMR integration heights in toluene‐d8 of the double doublet due to the cis‐isomer at δ 8.51 to that of the multiplet at δ 8. 15 which was kept constant during the whole experiment. The isomerization process was found to be first order and the Arrhenius activation parameters E8, ln A, Δ H≠ and ΔS≠ were calculated as 27.84 kJ/mol, 6.71, 25.23 kJ/mol and −197.89 J/(K·mol), respectively. Besides, conformational analyses of both compounds based on molecular modeling were carried out and the results were used to compare with the experimental data.
Influence of bond valence on bond covalency in calcium doped lanthanum chromite
Authors: Wu Zhi‐Jian , Meng Quig‐Bo , Zhang Si‐Yuan
Published: September 2010

The influence of bond valence on bond covalence in Lal‐xCaxCrO3(x = 0.0, 0.1, 0.2, 0.3) has been studied by using semi empirical method. This method is the extortion of the dialectic description theory proposed by Phillips, Van Vetches, Levine and Tanaka (PVLT). In the calculation of bond valence, two schemes were adopted. The first is the equal‐valence scheme, and the second is Bond Valence Sums (BVS) scheme. Bath schemes suggest that for the title compound bond covalence be mainly influenced by bond valence, and insensitive to the Ca doping level. Generally speaking, larger bond valences usually result in higher bond covalence's.
Study on the energy transfer between UO2+2 and Eu3+ in sol‐gel derived titania matrix by luminescence spectroscopy
Authors: Fu Lan‐She , Zhang Hong‐Jie , Wang Shu‐Bin , Meng Qing‐Guo , Yang Kui‐Yue , Ni Jia‐Zuan
Published: September 2010

The TiO2 gel doped with UO2+2 and Eu3+ has been prepared by a sol‐gel method. The quenching of the UO2+2 emission by Eu3 + and the energy transfer from the excited state of UO2+2 to the ground state of Eu3+ have been investigated. The energy transfer has been studied by the measurement of luminescence lifetime τ, calculation of energy transfer efficiency WET and energy transfer rate ηET. The experimental results indicated that the quenching is combined static and dynamic mechanism, but the static mechanism is dominant.
Anodic synthesis and XPS analysis of La1‐x.NaxCu2O4
Authors: Zhao Liang‐Zheng , Zhang Jin‐Riao , Xu Cui‐Ying , Liu Shi‐Hong
Published: September 2010

The single phase La1‐xNaxCu2O4 crystals were synthesized by an electrochemical method from molten KOH/NaOH/KNO3 at 280–300°C while La2‐y NayCuO4 were prepared by precipitation from the same molten salt. The resulting crystals were characterized by using SEM, XRD, EDX and XPS. XPS analysis revealed that the La3d satellite structures of La1‐x NaxCu2O4 were quite different from those of La2‐y NayCuO4. These differences have been attributed tyo the changes in crystal structures, bond lengths and covalent character of the metal‐ligand bonds.
Synthesis and characterization of chromia‐pillared layered tetratitanate
Authors: Hou Wen‐Hua , Chen Ya‐Shao , Guo Can‐Xiong , Yan Qi‐Jie , Chen Yi , Chen Jing
Published: September 2010

The first chromia‐pillared layered tetratitanate was prepared by the reaction of layered tetramethylammonium tetratitanate with chromium (III) acetate [Cr(OAc)3] aqueous solution and subsequent calcination of the resultant solid product in air at 400°C. The obtained chromia‐pillared layered tetratitanate has an interlayer distance of 1.06 nm and a high thermal stability up to 600°C. It was also found that calcination in N2 led to the chromia‐pillared layered tetratitanate with relatively higher Brunauer‐Emmett‐Teller (BET) specific surface area (93.9 m2·g−1) and smaller average pore diameter (4.44 nm) than that in air (82.0 m2·g−1, 7.61 nm). Both Brönsted and Lewis acid sites (mainly Lewis type) are present on the chromia‐Pillared layered tetratitanate (500°C, N2, 8 h) and strong enough to still remain a small proportion of pyridine upon outgassing at 250°C. Moreover, ammonia temperature‐programmed desorption (NH3‐TPD) result showed that there were three NH3 desorption peaks at 160, 200 and 315°C, respectively. The corresponding acid amount is 41.3, 73.9 and 290.7 μmol·g−1. The total acid amount is 405.9 μmol·g−1.
Comparison of spline wavelet and orthogonal wavelet in processing analytical chemistry signals
Authors: Zheng Xiao‐Ping , Mo Jin‐Yuan
Published: September 2010

Spline wavelet and orthogonal wavelet are two widely used wavelet methods. In this paper, comparison of these two methods has been made, including their algorithm, properties and results of signal processing in analytical chemistry signals. It is found that spline wavelet is more effective than orthogonal wavelet in processing high noise signals. The curves obtained from spline wavelet are closer to the theoretical ones than those obtained from orthogonal wavelet and the errors of spline wavelet are smaller than those of orthogonal wavelet.
Mechanism of reduction of benzylidenemalononitrile by 1‐benzyl‐1,4‐dihydronicotinamide
Authors: Wang Hong‐Yi , Liu You‐Cheng , Zhu Xiao‐Qing , Guo Qing‐Xiang
Published: September 2010

The reduction of benzylidenemdononitrile by 1‐benzyl‐1,4‐dihydronicotinamide undergoes via a one‐step hydride transfer mechanism rather than a multistep mechanism involving initial electron transfer.
A highly enantioselective synthesis of 5‐(l‐menthyloxy )‐4‐substituted‐3‐chloro‐2(5H )‐furanones
Authors: Geng Zhe† , Huang Bin , Chen Qing‐Hua
Published: September 2010

In this paper, stereocontrolled tandem Michael addition‐elimination reaction of the novel chiral source, 5‐(l‐menthyloxy)‐3,4‐dichloro‐2(5H)‐furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5–(l‐menthyloxy)‐4‐substituted‐3‐chloro‐2(5H)‐furanones, were obtained in good yields with d. e. ⩾ 98% under mild conditions.
A simple and versatile method for the synthesis of soluble C60‐based polystyrene derivatives
Authors: Xiao L‐Xiang , Chen Yu , Shen Jian‐Zhong , Cai Rui‐Fang , Huang Zu‐Enxs
Published: September 2010

A new simple and useful method for the synthesis of soluble C60‐styrene copolymer is demonstrated Covalent attachment of C60 onto the polystyrene backbone has been confirmed by UV‐VIS absorption spectra, 13C NMR and SEM.
New spectroscopic methods for environmental measurement and monitoring
Authors: Steinfeid Jeffirey I.
Published: September 2010

The ability to monitor a broad range of chemical species in the atmosphere, geosphere, and hydrosphere is a key technology for addressing global environmental issues. This report surveys several high sensitivity spectroscopic techniques for this purpose, including Frequency‐Modulation‐Enhanced Remote Sensing, Intra Cavity Laser Absorption Spectroscopy, Cavity Ring Down Spectroscopy, and Raman Spectroscopy.
Solubility of stearic acid in supercritical CO2‐acetonitrile mixtures
Authors: Mao Can , Lu Jie , Han Bu‐Xing , Yan Hai‐Ke
Published: September 2010

The solubility of stearic acid in supercritical CO2with acetonitrile (CH3CN) cosolvent was measured at 318. 15 K in the pressure range hm 9.5 to 16.5 MPa, and the cosolvent concentration ranges from 0. 0 to 5.5 mol%. The solubility increases with acetonitrile concentration and pressure, and it also increases with the apparent density of CO2d1(moles of CO2in per liter of fluid) at higher co solvent concentrations. At lower d1, however, the solubility of the acid at lower acetonitrile concentrations is lower than that in pure CO2provided that d1is fixed, which is discussed qualitatively based on the clustering of the components in the system.
From pharmacophore to leads: Bioactive compound discovery via computer‐aided techniques
Authors: Yuan Shen‐Gang , Luo Shi‐Wei , Chai Ge‐Qing , Yao Jian‐Hua , Chen Hai‐Feng , Zheng Chong‐Zhi
Published: September 2010

Based on the concept of Green Chemistry, a new procedure of finding bioactive compounds and their synthetic routes by computer‐aided techniques was proposed. The procedure consists of pharmacopoeia search against a 3D structural database of natural products for lead discovery and computer‐aided synthesis design for avoiding un useful synthetic experiments. This work demonstrated that computer aided drug design and synthesis design would help us to make the consideration of environmental concerns systematically, rather than having to deal later with the unnecessary waste chemicals. Thus, it is shown that chemical computer‐aided design (CAD) is an indispensable part of Green Chemistry.
An undecanuclear iron (III) oxo‐hydroxo aggregate with near nanometer size: Synthesis and crystal structure of [Fe11O6(OH)6(O2CPh)3(O2CPhMe‐p)12]
Authors: Wei Yong‐Ge , Zhang Shi‐Wei , Liu Ye‐Qi , Shao Mei‐Cheng
Published: September 2010

The title compound is formed by controlled hydrolytic polymerization in nonaqueous solution of simple oxo‐bridged binuclear ferric salts under the presence of carboxylate ligands. The rhombohedral crystalline form of the cluster with six imidazole molecules, which has crystallographically required C3y symmetry, will be reported. The largest Fe—Fe distance in the undecairon oxo‐hydroxo cluster is about 0.68 nm and the cluster has a diameter near 2 nm, which implies that this cluster reach‐ a nanometer‐sized dimension.
Synthesis, structure and characterization of the trinuclear copper (I) complex [Cu3(μ3‐Br)2(dppm)3]Br
Authors: Yang Rui‐Na , Sun Yu‐An , Hu Xiao‐Yuan , Jin Dou‐Man
Published: September 2010

The novel trinuclear copper(I) complex [Cu3(μ3,‐Br)2(dppm)3]Br has been obtained by reaction of bis(diphenyl‐phosphino)methane (dppm) with cupric bromide. The title complex was characterized by single‐crystal X‐ray analysis, elemental analysis, molecular weight determination, 31P NMR and its conductivity was also measured. The [ Cu3 (dppm)3 Br2 ]+ cation consists of a triangular array of copper atoms, with dppm ligands (Ph2 PCH2 PPh2) bridging each edge of the triangle and two triply bridging Br groups bound to the two faces of the Cu3 unit. Crystallographic data: monoclinic, space group P21/c, a = 1.4739(4), b = l.7708(5), c = 2.8395(8) nm, β= 97.16(3)°, V = 7.353nm3, Z = 4, F(000)= 3296, Dcalc, = 1.472 g/cm3, μ = 26.478 cm−1, R=0.06, RW = 0.08, 4654 reflections observed with I3≥(I).
Structure and base properties of calcined hydrotalcites
Authors: Liu Hai‐Chao , Yang Xi‐Yao , Ran Guo‐Peng , Min En‐Ze , Liu Jian‐Ke , Ying Pin‐Liang , Xin Qin , Li Can
Published: September 2010

Five hydrotalcites with Mg/Al molar ratio range of 3–15 were prepared. The structure and basicity of Mg‐Al mixed oxides (Mg(Al)O) transformed from hydrotalcites were investigated by TPD, XPS, XRD, FT‐IR and NMR techniques. The results of elemental analysis and XPS indicate that Al is enriched in the surface regions of Mg(Al)O, and its amount increases with the Mg/Al molar do and the Calcination temperature. 27Al‐MAS‐NMR results show that Al exists in two chemical environments: tetrahedral aluminium (Al(t)) and octahedral aluminium (Al(o)) in Mg(Al)O. The amount of Al(t) increases with the Mg/Al molar ratio and the calcination temperature. It is assumed that A(t) may be mainly from the surface Al. Temperature‐programmed desorption (IPD) of CO2 shows that the number of basic sites of Mg(Al)0 samples increases with the Mg/Al molar ratio, and the maximum number of basic sites is obtained for hydrotalcite calcined at 773 K. Infrared spectra of adsorbed CO2 and B(OCH3)3 reveal that there are two kinds of basic sites: weak basic OH− sites and strong basic O2 sites on the Mg(Al)0 samples, the base strength depends on the Mg/Al molar do and calcination temperature.
LCAC‐SW quantum scattering dynamic study on the ion‐pair formation process
Authors: Ma Wan‐Yong , Feng Da‐Cheng , Cai Zheng‐Ting , Deng Cong‐Hao
Published: September 2010

LCAC‐SW method has been extended to study the reaction dynamics for ion‐pair formation processes. M+ X2→Mt + X2 reaction system involves two potential energy surfaces, i.e., the covalence state (M + X2) and the ionic state (M + X2) and their crossing effect. The working equations for calculating state‐to‐state probability have been derived based on the above two‐state model, Satisfied results d collinear state‐to‐state probabilities for K+ I2 → K+ + I2 ion‐pair formation system have been obtained.
Synthesis and structure of catena cadmium complex with 2‐hydroxo‐1‐naphthaldehyde thiosemicarbazono tetradentate ligand
Authors: Zhang Wen‐Xing , Li Jian , Si Shu‐Feng , Li Jim‐Jun , Ma Chang‐Qin , Jiang De‐Hua
Published: September 2010

The title ligand (H2L) and its complex [CdL(py)2]py (L= C12H9N3OS dianionic) have been synthesized and characterized. The complex structure determination indicates that Cd( II ) atom has a distorted octahedral coordination geometry. As an unusual tetradentate ligand, one L2 chelates one Cd( II ) atom using the O, S atoms and one N atom of the hydrazino group while its another N atom links to the neighbouring Cd atom. The bridging hydrazono groups extend the compound into a catena chain. The naphthoxy rings of each neighboring unit are alternatively arranged at opposite sides of the chain, and the ring planes on the same side are parallel.
A novel heteropolymetalate containing Fe4(OH)4 segment: Crystal structure of [Me4N]10[Fe4(OH)4(PW10O37)2]15H2O
Authors: Wu Jin‐Chuan , Chen Min‐Qin , Li Ming‐Xing , Xie Gao‐Yang , Jin Song‐Lin
Published: September 2010

[Me4N]10[Fe4(OH)4(PW10O37)2] 15H2O was synthesized by the reaction of FeCl3 6HzO, with A‐Na8HPW9O34 and Me4NBr. Crystal data: M = 6225.75, space group P21/c with he monoclinic parameters: a = 1.3228(5), b=3.5634(3), c = 1.5226(2) nm, β = 94.20(2), V = 7.1576nm3, Z = 2,Dc = 2.888 g/cm3, Mo Ka radiation (λ = 0.071069 nm), μ = 168.534 cm−1, F(000) = 5576, final R = 0.0428 and Rw = 0.1204 for 7086 observed reflections with I 2s̀(I). The structure of the title compound is the first structurally characterized heteropolymetalate with hydroxo‐bridging metal aggregation Fe4(OH)4 encapsulated in the dimer of Keggin polyoxoanion.
Enthalpy‐entropy compensation effect in gas chromatographic enantiomeric separation
Authors: Zhou Liang‐Mo , Nie Meng‐Yan , Wang Qing‐Hai , Zhu Dao‐Qian , Shen He‐Qing
Published: September 2010

In this paper, the enthalpy‐entropy compensation effect in the enantiomeric separation by modified cyclodextrins (CD) and diamide chiral stationary phase (GP) gas chromatography was investigated using the method of plotting Δ( ΔH) versus Δ(ΔG) 7hm combined with t‐test statistic analysis. The investigated racemates cover α‐phenylethylamine and its analogs, 2‐alkylamines, chiral acyclic alcohols, halogenated arylethanediol‐1, 2‐diperfluoropropionates, amino acid and its analogs, and two series of compounds containing chloro and bromo substituents. From the compensation analysis results, the effects of the diluent composition in the investigated chiral stationary phases, the size and the died pups on investigated cyclodextrins, the derivatization methods and the groups attached to the stereocenters on enantiomeric separation mechanisms were all discussed.
Syntheses of imidazolium‐bridged cyclodextrin dimers and their catalytic properties in the hydrolytic cleavage of p‐nitrophenyl alkanoates
Authors: Luo Mei‐Ming , Xie Ru‐Gang , Yuan De‐Qi , Lu Wei , Xia Ping‐Fang , Zhao Hua‐Ming
Published: September 2010

Two imidazolium‐bridged cyclodextrin dimers 3a and 3b were prepared by reacting 6‐deoxy‐6‐N‐imidazolyl‐β‐CD (2) with bis(bromomethyl) benzene. The catalytic properties of 2, 3a and 3b in the hydrolytic cleavage of p‐nitrophenyl alkanoates, in the form of acetate (PNPA), butanoate (PNPB), hexanoate (WH) and octanoate ( PNPO), were examined. CD dimers showed middling rate enhancements around neutrality. Catalytic rate constants ( kc) in the presence of 3a or 3b did not vary much with chain length of esters. In contrast, dissociation constants (Kd) and selectivity factors (kc/Kd) for “long‐chain” esters were much smaller and significantly larger than those for “short‐chain” ones respectively, indicating CD dimers 3a and 3b have good dimensional recognition ability and substrate selectivity in the hydrolytic cleavage of p‐nitrophenyl alkanoate. Their kinetic consequences are briefly interpreted.
Use of 3–(2′‐formyl‐1′‐chlorovinyl)coumarin in the syntheses of pyrazol, salicylaldazine and pyrimidine derivatives
Authors: El‐Deen Ibrahim M.
Published: September 2010

3–(Pyrazol‐5‐yl)coumarin (3) was prepared from condensation of 3–(2′‐formyl‐l‐chlorovinyl)‐coumarin (1) with hydrazine hydrate at room temperature, followed by cyclyzation with base. Salicylaldazine was prepared from methoxylation of 1 to give acetal7, followed by condensation of 7 with hydrazine hydrate at 80°C: Treatment of acetal 7 with thiourea yielded the corresponding 4‐substituted‐2‐thioxo‐2H‐pyrimidine[3, 4‐b]‐coumarin (12).
Convenient one‐pot synthesis of functionalized cyclopentene via Sm/TMSCI/t‐BuOH system mediated hydrodimerization cyclization of gem‐diactivated alkene
Authors: Wang Lei , Zhang Yong‐Min
Published: September 2010

Functionalized cyclopentenes could be prepared through Sm/TMSCl/t‐BuOH mediated hydrodimerization cyclization of gem‐diactivated alkene in one‐pot at room temperature. The trans‐ or trans, transform isomer is in the majority and the major product was isolated from its stereoisomers through the fractional crystallization method.
Allyl chloride/AIC13/ether cationic initiating systems for polymerization of 1,3‐pentadiene
Authors: Peng  , Yuan Wu. , Liu Jia‐Lin , Zhang Wen‐Chuan
Published: September 2010

Various ethers were used to mediate the polymerization of 1,3‐pentadiene (PD) initiated by AlCl3 and by allyl chloride (AllyCl)/AlCl3. The introduction of the ethers exert considerable effects on polymer yield and molecular weight due to its interaction with the propagating carbocation. The carbocation reactivity is reduced by this interaction which is subject to the ether's nucleophilicity determined by the steric hindrance of groups adjacent to oxygen. The reduction of carbocation reactivity gives rise to a decrease of polymer yield owing to inhibition of propagation but results in an augmentation of molecular weight due to suppression of various side reactions such as terminations. By using suitably nucleophilic ethers such as diphenyl ether, the polymerization can be mediated to give an high molecular weight polymer in high yield.
Photocatalytic reduction of dichromate by titanium dioxide supported on hollow glass microbeads
Authors: Chen Shi‐Fu , Cheng Xue‐Li
Published: September 2010

The photocatalytic reduction of dichromate using TiO2/beads as a photocatalyst was studied. The results showed hat 3.8 × 104 mol/dm3 of dichromate can be completely reduced into Cr3+ after illumination far 35 min with a 375 W medium pressure mercury lamp. The effects of factors such as the amount of TiO2/beads, initial concentration of dichromate, initial pH, nitrogen and oxygen atmosphere, and concentration of Fe3+ on the photocatalytic reduction of dichromate were investigated. A possible mechanism of the photocatalytic reaction was proposed. After illumination for 200 h, no significant loss of photocatalytic activity of TiO2/beads was observed.
Asymmetric allylation of aldehydes and alkylation using “carbon‐centered” chiral organosilicon compounds
Authors: Wang Dong
Published: September 2010

The effects of the chiral substituents attached to silicon on the stereoselectivity of the reactions of C‐centered chiral silicon compounds wm examined. The investigation was focused on the asymmetric C—C bond formation reaction of chiral allylsilanes and α‐silylallyl anions with aldehydes. The functionalities of the substituents on silicon can be manipulated to improve the stereoselectivities of the reactions remote from silicon atom.
Mixed activation and mixed inhibition of the oxidoreductase activity of Rhus vernicifera laccase by different Pd2+ ion concentration
Authors: Tu Chu‐Qiao , Liang Hong , Wang Guang‐Hui
Published: September 2010

Kinetic experiments were performed to study the effects of Pd2+ ion on the oxidation of 5,6‐dibromo‐2, 3‐dicyanohydroquinone catalyzed by Rhus vernicifera laccase under condition of pH 4.5 and 30 ± 0.1°C. The results showed that the mixed activation could be observed when Pd2 ion was at low concentrations. The competitive and non‐competitive activation constants were 9 × 10−‐6 and 2 × 10−‐6 mol/L, respectively. With the increase of Pd2+ ion concentration, the activation was gradually converted into mixed inhibition, and the competitive and non‐competitive inhibition constants were 6 × 10−‐6 and 32 × 10−‐6 mol/L, respectively.
Synthesis characterization and magnetic properties of μ‐iodanilato dinuclear oxovanadium(IV) complexes
Authors: Li Yan‐Tuan , Yan Cui‐Wei , Zhou Qi‐Zhi , Liao Dai‐Zheng
Published: September 2010

Five oxovanadium(IV) dinuclear complexes described by the overall formula [(VO)2(IA)L2SO4, where IA repents the dianion of iodanilic acid and L denotes 2, 2′‐bipyridine (bpy); 4,4′‐dimethy12,2′‐bipyridine (Meo‐bpy); 1,10‐phenanthroline (phen); 4,7‐diphenyl‐l, 10‐phenanthroline (Ph2‐phen) and 5‐nitro‐1, 10‐phenanthroline (NO2‐phen), have been synthesized and characterized by elemental analyses, molar conductivity and roomtemperature magnetic moment measurements, IR and electronic spectral studies. It is proposed that these complexes have IA‐bridged structures and consist of two oxovanadium(IV) ions each in a square pyramidal environment. The complexes (VO)2(IA) (bpy)2]SO4, (1) and[(VO)2( IA) (phen)2 ]SO4 (2) were further characterized by variable temperature (4.2–300 K) magnetic susceptibility measurements and the observed data were fitted to the modified Bleaney‐Bowers equation by the least‐squares method, giving the exchange integral J = ‐ 2.15 m−1 for 1 and J = ‐ 9.88 cm−1 for 2. This result indicates that there is a weak antiferromagnetic spin‐exchange interaction between the two VO2+ ions within each molecule.
Synthesis, electrochemistry and fluorescence of four new Ru(phen)2/3+ derivatives
Authors: Wang Peng , Zhu Guo‐Yi
Published: September 2010

Four typical LB monolayer film materials, Ru(phen)2/3 + complexes with one ligand attached to different long chain alkyl amides, were designed and synthesized. Their chemical structures were identified by the techniques of FT‐IR, 1H NMR and ESI‐MS. Also, UV‐Vis, electrochemistry and fluorescence of these complexes are reported.
Structure determination of glycopeptide of p‐momorcharin
Authors: Li Yi‐Li , Ma Kan , Wu Hou‐Ming , Ye Guo‐Jie , Jin Shan‐Wei , Wang Yu
Published: September 2010

The structure of the N‐linked oligosaccharide chain of β‐momorcharin, a ribosome‐inactivating protein from the seeds of Momordica charantia Linn (Cucurbitaceae) was determined. A glycopeptide liberated by pronase digestion of the glycoprotein was subjected to amino acid and neutral carbohydrate analysis to establish the composition of amino acid and sugar residues. The sequences and glycosylation linkages of the sugar and amino acid residues in the glycopeptide were determined as Manal‐6(Xylβ1‐2)‐Manβ1‐4GlcNAcβ1‐4(Fucal‐3)‐GlcNAc‐Asn‐Leu by 2D‐NMR spectroscopy and FAB‐MS data.
Synthesis and characterization of organotitanium substituted heteropolytungstosilicates and their biological activity
Authors: Wang Xiao‐Hong , Sun Zhen‐Gang , Liu Jing‐Fu
Published: September 2010

Tris, di‐( organotitanium) substituted tungstosilicates α,β ‐ (CpTi)3(SiW9037)17– and γ‐[(CpTi)2(SiW10O38)] 6– were prepared by the reaction of C2TiC12 (Cp= η‐C5H5) with a,β‐SiW9 O9/34(noted α,β Siv9,), γ‐SiWO8/36 (noted γ‐SiW10) The products were characterized by means of elemental analysis, IR, 1H NMR, 183W NMR and polarography. 183W NMR spectra of the complexes support the stoichiometry of the new heteropolyanions and the probable retention of the A‐XW9 or γ‐SiWlO units. And the organotitanium substituted compounds showed promising in vitro antitumor activity in two of human tumor cell lines.
A practical stereoselective synthesis of (S)‐( ‐ )‐ofloxacin
Authors: Yang Yu‐She , Ji Ru‐Yun , Chen Yu‐Xian
Published: September 2010

A very efficient and practical procedure for preparation of ( S)‐( ‐ )‐ofloxacin has been developed (10 steps, overall yield ⩾45%). The key step of this approach is the regioselective nucleophilic substitution of 2‐position fluorine atom of 2,3,4 tirfluoronitrobenzene by (S)‐glycerol acetonide.
Highly selective hydrohalogenation reaction of substituted 23‐allenoates
Authors: Ma Sheng‐Ming , Wang Guang‐Wei
Published: September 2010

The hydrohalogenation reaction of 1‐alkyl substituted 1,2‐allenyl carboxylic acid esters (1) with MX (M= Na, or Li, X= Cl, Br, I) afforded a mixture of β,γ‐unsaturated 3‐halo–3‐alkenoates (2) and Q,P unsaturated 3‐halo‐2‐alkenoates (3) in HOAc, while using a mixture of HOAC‐CF3CO2H (1:1) or CF3C2H as the reaction medium the corresponding reaction cleanly produced β,γ ‐unsaturated 3‐hale3‐alkenoates (2) as the sole products in high yields. The subsequent coupling reactions were studied.
Samarium mediated pinacol coupling of carbonyl compounds in the presence of a catalytic amount of iodine under aqueous media
Authors: Wang Lei , Zhang Yong‐Min
Published: September 2010

In the presence of a catalytic amount of iodine, metallic samarium mediated pinacol coupling of carbonyl compounds has been carried out under saturated aqueous Nl&Cl‐THF conditions at mom temperature. It gives corresponding 1,2‐diols in god yields.
On the accuracy of the potential harmonic functions
Authors: Yi‐Xuan Wang, , Lin‐Wei Li, , Wen‐Sheng Bian, , Cheng‐Bu Liu, , Cong‐Hao Deng,
Published: September 2010

The matrix elements of the correlation function between symmetric potential harmonics am simplified into the analytical summations of the grand angular momenta by dy using the recurrence and coupling relations of the potential harmonics. 'The correlation‐function potential‐harmonic and generalized‐Laguerre‐function method (CFPHGLF), recently developed by us, is applied to the S states of the helium‐like systems for Z = 2 to 9. The results exhibit good convergence with the bases in tern of both the angular and radial directions. The final eigen‐energies agree excellently with the best s‐limits of the variational configuration interaction (CI) method for the involved low‐lying S states. The accuracy of the potential harmonic (PH) expansion scheme is discussed relative to the exact Hylleraas CI results (HCI), and Hartree‐Fock results. Moreover, suggestion is given for the future improvement of the PH scheme.
Interactions of oxidative radicals with N‐phosphoryl dipeptide derivatives
Authors: Gao‐Sheng Chu, , Jia‐Fu Chen, , Zhi‐Cheng Zhang, , Si‐De Yao,
Published: September 2010

The interactions of oxidative radicals (Br2−‐, HO− etc.) with N‐phosphoryl dipeptide derivatives (NDM‐TrpOMe and NDT‐MetOMe) have been investigated by using pulse radiolysis at different pH values. It has been found that Br2−‐ and HO− radicals oxidize the Met‐site and Trp‐site in the dipeptide derivatives via formation of the three‐electron‐bonded intermediate and indolyl radical simultaneously. Then the intramolecular electron transfer along the peptide backbone occurs. The rate constants of electron transfer, k, have been determined and the reaction mechanism has been deduced.
Catalytic reduction of NOx by CO on hydrotalcites‐derived mixed oxides CoAlM and MgAlM (M=Cr, Mn, Fe, Co, Ni, Cu)
Authors: Yu Liu, , Xue‐Zhong Wang, , Xiang‐Guang Yang, , Yue Wu,
Published: September 2010

Two series of mixed oxides, GIAlM and MgAlM (M= G, Mn, Fe, Co, Ni, Cu), were prepared by calcining their corresponding hydrotalcite‐like compounds (HTLc). The ratio of Mg: Al: M (or Co: Al: M) was 3:1:1. The catalytic activity of all samples for the reaction of NO + CO was investigated. The results showed that the activity of CoAlM was much higher than that of MgAlM. The structure and the property of redox were characterized by XRD and H2‐TPR. The results indicated that only MgO phase was observed after calcining MgAlM hydrotalcites, and the transition metals became more stable. The spinel‐like phase appeared in all of CoAlM samples after the calcination, and the transition metals were changed to be more active, and easily reduced. The activities of three series of mixed oxides CoAlCu obtained from different preparation methods, Different ratio of Co: Al: Cu and at different calcination temperatures. were studied in detail for proposing the mechanism of reaction. The ability of adsorption of NO and CO were investigated respectively for supporting the mechanism.
Rare earth complexes with noncyclic polyethermethionine Schiff base
Authors: Ke‐Min Yao, , Gui Lu, , Lian‐Fang Shen,
Published: September 2010

A novel Schiff base (TAMET) was synthesized by the condensation of tetraglycol aldehyde with methionine and a mild oxidant CrO3. (C5H5N)2 was selected for the reaction. Seven new rare earth complexes with this Schiff base have been synthesized and characterized by elemental analysis, TG‐DTA, molar Conductivity, magnetic susceptibility and IR, especially 1H NMR spectra. Information was obtained from reflectance spectra and the coordination of sulfur atom to rare earths was discussed. The experimental results show that these compounds have some biological activity and could dispose of O2−‐.
Preparation and characterization of phenyl carbamate derivative β‐cyclodextrin bonded phase for chiral HPLC
Authors: Hui Chen, , Xian‐Yu Lu, , Ru‐Yu Gao, , Qin‐Sun Wang,
Published: September 2010

A partially substituted β‐cyclodextrin chiral stationary phase was prepared by the reaction of phenyl isocyanate. The enantiomers of a series of O,O‐diethyl(p‐methylbenzenesulfonamido)‐aryl(or alkyl)‐methylphosphonates were studied on the prepared phenyl carbamate derivative β‐cyclodextrin bonded phase and a commercial (S)‐(+)‐1–(1‐naphthyl) ethylcarbamate derivative β‐cyclodextrin bonded phase on normal phase chromatographic condition. Results show that the prepared phenyl carbamate derivative β‐cyclodextrin bonded phase has better enantiomeric selectivity to the series of compounds. A chiral recognition mechanism was suggested for the separation of these novel organic phosphorus enantiomers.
Design, synthesis and bioactivity of novel herbicides targeted ALS (VII): Quantitative structure‐activity relationships of herbicidal sulfonylureas
Authors: Guang‐Fu Yang, , Hua‐Zheng Yang,
Published: September 2010

The quantitative relationship between the structures of 20 sulfonylureas and their herbicidal activities against rape was analyzed using physicochemical parameters and regression analysis. The results showed that the electronic properties of the molecules are the dominant factor to the activity and there is apparently an optimum electronic property (Σs̀ or pKa) for the molecules to fit the receptor. Combined with the preview QSAR results for herbicidal triazolopyrimidine‐2‐sulfonamides, we can conclude that the structure‐activity relationships of these two sets of compounds are identical, which suggested that these two sets of compounds acted on the same target site.
Primary structure of β‐momorcharin, a ribosome‐inactivating protein from the seeds of Momordica Charantia Linn (Cucurbitaceae)
Authors: Guo‐Jie Ye, , Bao‐Yuan Lu, , Shan‐Wei Jin, , Rui‐Qing Qian, , Yu Wang,
Published: September 2010

The complete amino acid sequence of β‐momorcharin, a ribosome‐inactivating protein from the seeds of Momordica charantia Linn (Cucurbitaceae) has been determined. This has been done by the sequence analysis of peptides obtained by enzymatic digestion with trypsin, chymotrypsin and S.aureus V8 protease, as well as by chemical cleavage with BNPS‐skatole. The protein consists of 249 amino acid residues containing one asparagine ‐ linked sugar group attached to the site of Asn 51 and has a calculated relative molecular mass of 28,452 Da without addition of the carbohydrate. Comparison of this sequence with those of trichosanthin and other ribosome‐inactivating proteins from different species of plants shows a significant homology with each other. Regarding the similarity of their biological properties, an active domain of these proteins has been predicted here.
Kinetic model of induced codeposition of Ni‐Mo alloys
Authors: Yue Zeng , Muig Ma , Xiao‐Ming Xiao , Ze‐Lin Li , Shi‐Xun Lian , Sbao‐Min Zhou
Published: September 2010

The kinetic model of induced codeposition of nickel‐molybdenum alloys from ammonium citrate solution was studied on rotating disk electrodes to predict the behavior of the electrode‐position. The molybdate (MoO42−) could be firstly electro‐chemically reduced to MoO2, and subsequently undergoes a chemical reduction with atomic hydrogen previously adsorbed on the inducing metal nickel to form molybdenum in alloys. The kinetic equations were derived, and the kinetic parameters were obtained from a comparison of experimental results and the kinetic equations. The electrochemical rate constants for discharge of nickel, molybdenum and water could been expressed as k1,(E) = 1.23 × 10−9 CNexp( ‐ 0.198 FE/RT) mol/(dm2 · s), k2 (E) = 3.28 × 10−10 CMoexp ( ‐ 0.208FE/ RT) mol/(dm2 · s) and k3(E) = 1.27 × 10−6 exp ( ‐0.062FE/ RT) mol/(dm2 · s), where CN and CMo, are the concentrations of the nickel ion and molybdate, respectively, and E is the applied potential vs. saturated calomel electrode (SCE). The codeposition process could be well simulated by this model.
Binding equilibrium study between Mn(II) and HSA or BSA
Authors: Hong Liang , Chu‐Qiao Tu , Hong‐Zhi Zhang , Xing‐Can Shen , Yong‐Qia Zhou , Pan‐Wen Shen
Published: September 2010

The binding of Mn(II) to human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by equilibrium dialysis at physiological pH (7.43). The Scatchard analysis indicates that there are 1.8 and 1.9 strong binding sites of Mn(II) in HSA and BSA, respectively. The successive stability constants which are reported for the first time are obtained by non‐linear least‐squares methods fitting Bjerrum formula. For both Mn(II)‐HSA and Mn(II)‐BSA systems, the order of magnitude of K1 was found to be 104. The analyses of Hill plots and free energy coupling show that the positive cooperative effect was found in bom Mh(II)‐HSA and Mn(II)‐BSA systems. The results of Mn (II) competing with Cu (II) Zn(II), Cd(II) or Ca(II) to bind to HSA or BSA further support the conjecture that there are two strong binding sites of Mn(II) in both HSA and BSA. One is most probably located at the tripeptide segment of N‐terminal sequence of HSA and BSA molecules involving four groups composed of nitrogen atoms, and the fifth coordination atom is the carboxyl oxygen of Asp1. The coordinated atoms of the other are most probably almost all oxygen atoms.