A Tri‐µ‐O‐S‐O Manganese Dimer: Synthesis,Structral and EPR Study

A Tri‐µ‐O‐S‐O coordinative manganese dimer: [Mn₂(SO₄)₂(phen)₄]·CH₃OH (phen1,10‐phenanthroline) ( 1 ) was yielded by the reaction of 1,10‐phenanthroline and MnSO₄·H₂O in a mixed solvent of methanol and acetonitrile under room temperature and was structurally characterized. Single crystal analysis shows that complex 1 has polymeric structure based on binuclear Mn(II) units bridged by O‐S‐O groups of two SO₄²⁻ anion. The UV spectrum of the complex clarifies that each metal‐organic building unit parallels with each other through the Π‐Π interactions of face‐to‐face separations of two 1,10‐phen planes among the complex, forming a layered structure. And the electronic paramagnetic resonance (EPR) signal clearly indicates that those manganese atoms in complex 1 are in +2 oxidation states.     

Synthesis of 14-aryl or alkyl- 14H-dibenzo[a,j]xanthenes promoted by Mg(HSO4)2

14-Aryl or alkyl-14H-dibenzo[a,j]xanthenes were prepared by condensation of 2-naphthol and aldehydes in the presence of Mg（HSO₄）₂ as an efficient,cheap,readily available and eco-friendly catalyst.This procedure has the advantages of high yields,easy work-up,short reaction times,and green conditions.     

New Synthetic Route of Two Active Isomeric Metabolites of Erlotinib and Their Bioactivity Studies against Several Tumor Cell Lines

The synthesis and differential antiproliferative activity of two active isomeric metabolites of erlotinib were investigated. This synthetic process had demonstrated to avoid the unstable 4‐chloroquinazoline intermediates and long procedures. New intermediates and final compounds were identified by ¹H NMR, ¹³C NMR and ESI‐TOF MS, and their purities were determined by high performance liquid chromatography. In vitroproliferative assay indicated that these two metabolites possessed antiproliferative activity against some conventional tumor cell lines and EGFR tyrosine kinase over‐expression tumor cell lines as compared to erlotinib control, and their antitumor activity in cellular level was first reported here.     

离子色谱法同时测定茶叶中多种阴离子

研究了离子色谱法同时测定茶叶中F<'->、Cl<'->、NO<,2><'->、NO<'-><,3>、H<,2>PO<'-><,4>和SO<'2-><,4>6种无机阴离子含量的方法.茶叶样品中6种阴离子经95℃超声浸提20 min后,以浓度为1.92 mmol/L Na<,2>CO<,3>和1.80 mmol/L NaH...     

Voltammetric study on interaction of cysteine with type I-collagen in the aqueous medium

Interaction of cysteine with type I-collagen from bovine achilles tendon in the aqueous solutions has been examined using square wave voltammetry (SWV) and cyclic voltammetry (CV) techniques. In the absence of cysteine, type I-collagen gives a reversible peak at ?0.114 V in Britton-Robinson (B-R) buffer (pH 4.0). The electrochemical parameters (I _p/f, E _p/f, E _p/pH, I _p/pH, I _p/v, I _p/v^1/2) of type I-collagen have been also studied. In addition, it has been determined that there is a linear relationship between current and concentration of type I-collagen. On the other hand, cysteine exhibits a reversible peak at ?0.383 V due to the reduction of mercurous cysteine thiolate. By using a hanging mercury drop electrode in aqueous solutions, SWV and CV voltammograms obtained for type I-collagen in the presence of cysteine indicate that there is an interaction between type I-collagen and cysteine. In the presence of cysteine, peak current of type I-collagen decreases and a new peak is observed at ?0.121 V for cysteine which is bonded to type I-collagen.     

Quantum‐chemical,IR, NMR,and X‐ray diffraction studies on 2‐(4‐chlorophenyl)‐1‐methyl‐ 1H‐benzo[d]imidazole

The title molecule, 2‐(4‐chlorophenyl)‐1‐methyl‐1H‐benzo[d]imidazole (C₁₄H₁₁ClN₂), was prepared and characterized by ¹H NMR, ¹³C NMR, IR, and single‐crystal X‐ray diffraction. The molecular geometry, vibrational frequencies, and gauge including atomic orbital (GIAO) ¹H and ¹³C NMR chemical shift values of the title compound in the ground state have been calculated by using the Hartree‐Fock (HF) and density functional theory (DFT/B3LYP) method with 6‐31G(d) basis sets, and compared with the experimental data. The calculated results show that the optimized geometries can well reproduce the crystal structural parameters, and the theoretical vibrational frequencies and GIAO ¹H and ¹³C NMR chemical shifts show good agreement with experimental values. The energetic behavior of the title compound in solvent media has been examined using B3LYP method with the 6‐31G(d) basis set by applying the Onsager and the polarizable continuum model (PCM). Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, and nonlinear optical (NLO) properties of the title compound were investigated by theoretical calculations. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

2-氰基-3-(4-甲基苯并[d]噻唑-2-氨基)-3-苯基丙烯酸酯类化合物的合成及抗病毒活性

以氰乙酸乙酯(氰乙酸)为起始原料,经酯化、缩合、氯化,然后与2-氨基-4-甲基苯并[d]噻唑反应,合成了20个新化合物4.所有化合物结构经过IR,1H NMR,13C NMR和元素分析确证.初步生物活性测试表明:在500μg·mL-1浓度下,该类化合物4具有一定的抗黄瓜花叶病毒(CMV)及抗烟草花叶病毒(TMV)室内活体治疗活性,其中化合物4b,4o,4q对CMV具有较好的活体治疗活性(抑制率分别为45.81%,43.20%,43.09%),化合物4d,4f,4h,4l对TMV具有较好的活体治疗活性(抑制率分别为45.68%,45.19%,45.86%,44.32%),对照药宁南霉素的活体治疗活性分别为56.31%,54.63%.     

Structural Characterization and Toxicity Prediction of Some Organic Compounds

A new molecular structural characterization(MSC)method called molecular vertexes correlative index(MVCI)was constructed in this paper.The index was used to describe the structures of 45 compounds and a quantitative structure-activity relationship(QSAR)model of toxicity(–lgEC50)was obtained through multiple linear regression(MLR)and stepwise multiple regression(SMR).The correlation coefficient(R)of the model was 0.912,and the standard deviation(SD)of the model was 0.525.The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The Leave-One-Out(LOO)Cross-Validation(CV)correlation coefficient(RCV)was 0.816 and the standard deviation(SDCV)was 0.739,respectively.For the external validation,the correlation coefficient(Rtest)was 0.905 and the standard deviation(SDtest)was 0.520,respectively.The results showed that the index was superior in molecular structural representation.The stability and predictability of the model were good.     

Highly Regioselective Synthesis of 3′-O-Acyl-Trifluridines Catalyzed by Pseudomonas cepacia Lipase

3'-O-Acyl-trifluridines were prepared successfully through an enzymatic approach for the first time. Among the ten commercially available lipases tested, Pseudomonas cepacia lipase displayed the highest regioselectivity towards the acylation of 3'-hydroxyl of trifluridine. Furthermore, the effects of some crucial factors on the enzymatic myristoylation of trifluridine were examined. The optimal reaction medium, molar ratio of trifluridine to vinyl myristate and reaction temperature were found to be anhydrous THF, 1:7 and 50 °C, under which the reaction rate, substrate conversion, and 3'-regioselectivity were 63.9 mM/h, >99.0%, and 99%, respectively. Additionally, the enzyme recognition of the chain length of the acyl donors was investigated. The results showed that 3'-regioselectivity of the enzyme maintained 99% with the increment of acyl chain length (C6, C10, and C14). The reason might derive from the strong hydrophobic interaction between 5-CF(3) group of the base moiety and Leu 287 located in the medium-sized pocket of the active site.     

Ultrasonication-assisted extraction and preconcentration of medicinal products from herb by ionic liquids

Ionic liquid-based extraction of medicinal or useful compounds from plants was investigated as an alternative to supercritical fluid, cloud point and conventional organic solvent extractions. The method integrated extraction and preconcentration. Medicinal products were first extracted by an ionic liquid solution, part of which was then converted to a hydrophobic form by anion metathesis for preconcentration. The remaining soluble ionic liquid acted as a dispersive agent to enhance the efficiency of preconcentration. Protein in the extract was precipitated spontaneously without addition of further solvents. Ultrasonication assisted this method for extraction and preconcentration of cryptotanshinone, tanshinone I and tanshinone II A from Salvia Miltiorrhiza Bunge. 0.233 mg g⁻¹, 0.695 mg g⁻¹ and 0.682 mg g⁻¹ of each, respectively, were extracted using [OMIM][Cl], and preconcentrated in a [OMIM][PF₆] phase at respective concentrations of 148.1, 507.1 and 486.1 μg mL⁻¹. The method exhibited potential applicability with other medicinal products.