A NEW METHOD FOR SYNTHESIZING 2-ALKOXYCARBONYLETHYLTIN TRICHLORIDES AND THEIR DIMETHYLSULFOXIDE COMPLEXES

Abstract: A new method based on transesterification reactions for synthesizing 2-alkoxycarbonylethyltin trichlorides(1) and their dimethylsuloxide complexes (2) was reported. 1 and 2 were characterized by elemental analysis,IR and VNMR spectra. The possible mechanism for their trans esterifications was suggested.

A NEW APPROACH TO SYNTHESIZING 2－ALKOXYCARBONYL －2－METHYL ETHYL TIN TRICHLORIDES AND THEIR COMPLEXES WITH DBSO AND HMPA

A new approach based on transesterification reaction to synthesizing 2-alkoxycarbonyl-2 -methyl ethyl tin trichlorides and their complexes with dibenzylsulfoxide (DBSO) and hexamethylphosphoramide (HMPA )was reported. They were characterized by elemental analysis,IR and HNMR spectra. The possible mechanism for transesterifications was suggested.

Synthesis of Triphenyltin 2-(1,2-Ethylenedithio) Methylene-3-Oxo-5-Aryl-4-Pentenoate

Under esterification conditions, 2-(1,2-ethylenedithio) methylene-3-oxo-5-aryl-4-pentenoic acid 3 afforded the decarboxylated products 4. The triphenyltin 2-(1, 2-ethylenedithio) methylene-3-oxo-5-aryl-4-pentenoates 5 were obtained in high yields when 3 reacted with triphenyltin hydroxide.

Grey-relation Analysis of Traffic System and Urbanization in Jilin Province of China

It has been long believed there should be some relations between traffic system and urbanization,but the in-teraction between them,especially on the regional level,has been not in consideration due to the difficulty in quantitative analysis.Based on the development of Jilin Province during 1981-2003,the paper analyzed the relation with the grey-relation model which was adjusted to fit specific problem,and came to some conclusions.Firstly,there exists ob-vious and strong correlation between traffic system and urbanization.Secondly,urbanization responds to the develop-ment of traffic system mainly on the level of urbanization,such as population and developed area,however,less on urbanization quality.Thirdly,traffic system influences urbanization as a whole except for several peculiar factors,which means we should optimize the whole traffic system to promote urbanization.Based on those conclusions,the paper illustrated the mechanism of traffic system,promoting urbanization scale and urbanization quality.

SYNTHESIS AND ANTI－HIV－1 ACTIVITY OF HETEROPOLY COMPLEXES OF TUNGSTOTITANOPHOSPHATES CONTAINING RARE EARTH ELEMENTS

ＳＹＮＴＨＥＳＩＳ ＡＮＤ ＡＮＴＩ－ＨＩＶ－１ ＡＣＴＩＶＩＴＹ ＯＦ ＨＥＴＥＲＯＰＯＬＹ ＣＯＭＰＬＥＸＥＳ ＯＦ ＴＵＮＧＳＴＯＴＩＴＡＮＯＰＨＯＳＰＨＡＴＥＳ ＣＯＮＴＡＩＮＩＮＧ ＲＡＲＥ ＥＡＲＴＨ ＥＬＥＭＥＮＴＳＳＹＮＴＨＥＳＩＳＡ...

PREPARATION AND CHARACTERIZATION OF NIOBIUM－CONTAINING DIMOLYBDO－15－TUNGSTODIPHOS－PHORIC SALT

Preparation of P2W15M15Mo2NbO627- was reported in the paper. It was characterized by elementry analysis, IR,UV, polarography, 183 W-NMR and XPD spectra. All results showed the structure of the heteropoly anion was the Dawson type.

Magnetic properties of heteropolyoxometalates

The progress of the study on the magnetic properties of heteropolyoxometalates during the late decade is reviewed. Some anions of heteropolyoxometalates containing magnetic atoms, such as [M4（H2O）4(PW9O342]10- and [M4（H2O）4(P2W15O562]16-[M= Co（ Ⅱ ）, Zn（ Ⅱ ）, Cu（ Ⅱ ）, Mn（ Ⅱ ）,Ni（ Ⅱ ）], and [GaW9O37M3（H2O）3]n-[M= Fe（ Ⅲ ）, Cu（ Ⅱ ）, Co（ Ⅱ ）], showed ferromagnetic and antiferromagnetic properties. The combination of heteropoly anions and organic π-donor of TTF+ （tetrathiofulvalene cation） results in a variety of magnetic properties. Furthermore, there is an interaction between the inorganic and organic components. The electrocrystallization technique can prepare the organic-inorganic salts of this kind, which will become the new member of molecular magnetic materials.Heteropoly blue is a kind of the mixed-valence complexes and its reduction electrons can be delocalized over anionic framework. The further study on the magnetic properties of heteropolyoxometalates

DNA Methylation Affects Gene Alternative Splicing in Plants： An Example from Rice

Dear Editor,Alternative splicing （AS） of pre-mRNA is an evolutionarily conserved mechanism to increase transcriptomic and proteomic complexity, and hence phenotypic diversity, via the production of multiple mRNA isoforms from a single gene （Reddy et al., 2013）. AS is regulated by various cis-acting regulatory elements and RNA-binding proteins （Reddy et al., 2013）.

Roles of histones and nucleosomes in gene transcription

This article reviews the latest research developments in the field of eukaryotic gene regulation by the structural alterations of chromatin and nucleosomes. The following issues are briefly addressed: (i) nucleosome and histone modifications by both the ATP-dependent remodeling complexes and the histone acetyltransferases and their roles in gene activation; (ii) competitive binding of histones and transcription factors on gene promoters, and transcription repression by nucleosomes; and (iii) influences of linker histone HI on gene regulation. Meanwhile, the significance and impact of these new research progresses, as well as issues worthwhile for further study are commented.

Salt glands in Glycine soja L.China

A scanning electron microscope observation is carried out on Glycine soja L., which grows around the estuary of the Yellow River, in Kenli County, Shandong Province. It is first discovered that there are salt glands, in the shape of balls, on the surface of the stems and leaves of G. soja L., and distributed at the intercellular layer. With a handle at the base, the salt glands are not equal in size, and show a layer-upon-layer structure. They have a diameter of 21 .6 μm, a handle length of 1.2 μm, their secretory pore’s diameter is 5.6 μm. There are two ways to secrete salt ions: younger glands secrete salt ions through the secretory pore, and mature glands by breaking themselves.

Supermolecular layered double hydroxides

Research progresses in the layered double hydroxides [M2+(1-x)M3+x(OH)2]x+An-x/n.mH2O intercalatedwith metal coordinate ions or oxometalates in the last ten years are reviewed. These layered double hydroxides are mainly intercalated with polyoxometalate (POM) ions, a LiAl-LDH photochemical assembly containing TiO2 and CH3(CH2)12COO- anions, together with Zn(TPPC) (porphy-rin derivate) and macrocyclic ligand-containing porphyrin derivate anions. Emphasis is put on the synthesis methods for intercalation of the anions into the interlayer regions, the characterization techniques and structures for the layeredcompounds and the newest research progress in the fields such as catalysis. The review also forecasts the prospects of the field.

CP embedding agent and its application to the serial section of the body wall tissue of insects

The key of tissue section technique is the selection and application of the embedding agent. Based on the specific characteristics of the tissue and outer skeleton of insects, a new kind of embedding agent, colophony and paraffin (CP), was used without destroying the integrity of insect organs. The tissue can be sliced continuously by the use of CP embedding technique. It solves the 3 difficult problems in the serial section of the organ and tissue of insect, namely stiff materials, thin section and continuity of sections. These difficult problems are not solved by any unitary tissue section technique that is used now, including the paraffin section technique. By using the CP embedding technique, any parts or organs (like antenna, leg and wing) and even the whole body of insects (mini body) can be sliced up continuously. It will open up wide possibilities for the study of inner structure, the interrelations among organs, the micro-characteristics and the physiological functions of insects

Synthesis and characterization of two novel coordination polymers based on the rigid 1H-1,2,3-triazole-4,5-dicarboxylic acid ligand

Two novel three-dimensional (3-D) coordination polymers, [Pb(HTDA)]n (1) and [Co5(TDA)2(H2TDA)2(H2O)8]n (2) [H3TDA = 1H-1,2,3-triazole-4,5-dicarboxylic acid], have been prepared by hydrothermal reactions and characterized by elemental analysis, infrared spectroscopy and single-crystal X-ray diffraction. Compound 1 is constructed from rod-shaped secondary building units (SBUs) and exhibits a 3-D network with (410·65)(410·63·82) topology. Compound 2 is built up from ligands bridging three different cobalt ions and exhibits a 3-D network with (4·82)3(4·82·103) topology. In addition, the thermal stabilities of the two compounds, the photoluminescence properties of compound 1 and the magnetic properties of compound 2 have been studied.

Synthesis, characterization and oxidative activity of heteropolyanion pillared layered compound

TRANSITION element trisubstituted and Ln bi-（1:11）series heteropolyanion with Keggin struc-ture are excellent catalyst with oxidizing properties.But they have some shortcomingssuch as poor stability and impossible recycle use when they are used in homogeneous oxidation.Anions（An-）,among hydroxides（LDHS）-like layers,having a general formula[M1-x2+Mx3+-

Visible-light photocatalytic H_2 evolution over a series of transition metal substituted Keggin-structure heteropoly blues

The visible light photocatalytic H 2 evolution activities of a series of transition-metal substituted Keggin-structure heteropoly blues K 6 SiW 11 O 39 M(H 2 O)·nH 2 O (M=Co,Ni,Cu and Zn) were systematically studied with Pt nanoparticles as co-catalyst.The H 2 evolution rates were 150,98,65 and 48 mol h-1g-1 for SiW 11 Cu,SiW 11 Ni,SiW 11 Co and SiW 11 Zn,respectively,meaning that the order of photocatalytic activity of these heteropoly blues from transition-metal substituted polyoxometalates was:SiW 11 Cu > SiW 11 Ni > SiW 11 Co > SiW 11 Zn.The catalysts could be efficiently reused for at least 5 cycles.

Syntheses and lyotropic liquid crystal properties of a series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30

A series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30, Na16[As4W30M4(H2O)2O112]·XH2O (M = Zn,Cu,Co,Ni,Mn and Cd), have been synthesized for the first time and structurally characterized by elemental analysis, IR and 183W NMR spectra. The crystal structure of Na16[As4W30Cu4(H2O)2O112]·63H2O was determined to be a triclinic system, of P1 symmetry, a = 1.2721(3) nm, b = 2.451 6(5) nm, c = 2.6450(5) nm,

Heat-shock protein 90 in Candida albicans

Researches on Candidal heat-shock protein 90 (HSP90) in recent years are summarized. Candida albicans is a commensal pathogen in human and animals. in immunocompromised individuals it behaves as an opportunist pathogen, giving rise to superficial or systemic infections. Systemic candidosis is a common cause of death among immunocompromised and debilitated patients, in which the mortality is as high as 70%. HSP90 is now recognized as an immunodominant antigen in C. albicans and plays a key role in systemic candidosis as a molecular chaperone. The 47-ku peptide is the breakdown product of HSP90. Patients who has recovered from systemic candidosis produce high titre of antibodies to 47-ku antigen, whereas the fatal cases have little antibody or falling titre? The three commonest epitopes of candidal HSP90 have been mapped, epitopes C, B and H. Epitopes C and H are immunogenic. The antibody probes of both epitopes may be developed into a new serological test agents for systemic candidosis due to rather

Progress in studies of angio-statin and its anti-tumor effects

Angiostatin is a 38 ku circulating angiogenesis inhibitor purified from the serum and urine of mice bearing a murine Lewis lung carcinoma. It is regarded as an internal fragment of plasminogen containing the first 4 Kringle structures. In vitro, angiostatin specifically inhibits endothe-lial cell proliferation. In vivo, it inhibits angiogenesis and suppresses the growth of such primary tumors as Lewis lung carcinoma and hemangioendotheliolma in mice.

Microdissection of chromosome 7B of common wheat and cloning of low-copy specific DNA sequences

The 7B chromosome of common wheat was microdissected from pollen mother cells of the 7B monosomic line of common wheat cv. Chinese Spring (CS). After proteinase K and DNA topoisomerase Ⅰtreatments, the isolated chromosomes were subjected to 1—3 rounds of DOPPCR amplification, which produced continuous DNA fragments ranging from 150 to 700 bp. Genomic Southern hybridization confirmed that the PCR products were originated from the wheat genome. Cloning of portion ( 】 200 bp) of the 3rd round DOP-PCR products (50 μL) could generate about 20 000 recombinant clones. Characterization of 50 randomly chosen clones indicated that 21 clones produced discrete PCR products with the size of 240—600 bp. Dot-blot hybridization showed that among the 21 clones, 11 (～ 55%) were of low-copy nature while 10 (～45%) were repetitive. Southern hybridization with the complete set of the CS 'nullisomic-tetrasomic (NT)' lines demonstrated that all the 6 low-copy clones were specific to either chromosome 7B or the 7th

Synthesis and characterization of trisubstituted heteropolytungstogermanates containing group 3A elements

Six new compounds, alpha,beta-KaHb[GeW(9)M(3)(H2O)(3)O-37]. xH(2)O(M = Al, Ga, In; a + b = 7) and alpha-K9H5[Ge2W18Ga6(H2O)(3)O-74]. 20H(2)O, were synthesized from the lacunary precursors a and beta-GeW9O3410- and characterized by elemental analysis, spectroscopy and electrochemistry. Tungsten-183 NMR spectra of the title complexes consist of two lines with intensity ratio 2:1 as expected for trisubstituted heteropoly anions. The intensity ratio of alpha-Ga compound is 1:2, which is different from others(a:1). With the help of FAB mass spectrum, we concluded that it is a dimer with D-3h structure in aqueous, and the others exist by monomers with C-3v structures.