STRUCTURE,MOLECULAR WEIGHT AND BIOACTIVITIES OF(1→3)-β-D-GLUCANS AND ITS SULFATED DERIVATIVES FROM FOUR KINDS OF LENTINUS EDODES

Lentinan samples,(1→3)-β-D-glucans containing 4.6-15.2 wt% proteins,coded as L-I_1 L-I_2 L-I_3 and L-I_4(L-I)were isolated from four kinds of Lentinus edodes.These glucans were treated with acetone to remove the protein in orderto obtain free protein glucans coded as LNP-I_1,LNP-I_2.LNP-I_3 and LNP-I_4(LNP-I).The free-protein polysaccharideswere sulfated to give derivatives(S-LNP-I)with degree of substitution(DS)from 0.4-0.8.The structural features andweight-average molecular weight(M_w)of the samples were investigated by using infrared spectroscopy,elemental analysis,^(13)C-NMR,size exclusion chromatography combined with laser light scattering(SEC-LLS)and viscometry.The effects ofstructure and conformation of the polysaccharides on antitumor activities were assayed in vivo(Sarcoma 180 solid tumors)and in vitro(Sarcoma 180,HL-60,MCF-7 and Vero tumors).The results indicated that the predominant species of thesamples L-I and LNP-I in 0.2 mol/L NaCl aqueous solution existed as triple-helical chains with high rigidity and in dimethylsulfoxide(DMSO)as single-flexible chains.Interestingly,the antitumor activities of LNP-I are lower than those of the nativeglucans(L-I),whereas their sulfated derivatives have higher inhibition ratio against Sarcoma 180 than LNP-I.The resultsreveal that the binding of protein,sulfated modification and the triple helix conformation are important factors in theenhancement of the antitumor activities of polysaccharides on the whole.

Mechanistic Investigation on Rhodium(III)-Catalyzed Cycloaddition of 2-Vinylphenol Derivatives with Ethyne or Carbon Monoxide by DFT Study

Rhodium-catalyzed cycloaddition reaction was calculated by density functional theory M06-2X method to directly synthesize benzoxepine and coumarin derivatives.In this work,we conducted a computational study of two competitive mechanisms in which the carbon atom of acetylene or carbon monoxide attacked and inserted from two different directions of the six-membered ring reactant to clarify the principle characteristics of this transformation.The calculation results reveal that:(i)the insertion process of alkyne or carbon monoxide is the key step of the reaction;(ii)for the(5+2)cycloaddition reaction of acetylene,higher energy is required to break the Rh−O bond of the reactant,and the reaction tends to complete the insertion from the side of the Rh−C bond;(iii)for the(5+1)cycloaddition of carbon monoxide,both reaction paths have lower activation free energy,and the two will generate a competition mechanism.

Use of Ultrasound and Microwave Irradiation for Clean and Efficient Synthesis of 3,3’-(Arylmethylene)bis (2-hydroxynaphthalene-1,4-dione) Derivatives

Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic irradiation for 5 min at room temperature and microwave irradiation for 15 min at 70°;C. Two of the nine derivatives, compounds 3-e and 3-i, obtained from 3-bromo-hydroxybenzaldehyde and 5-methylfuran-2-carbaldehyde, respectively, are previously unpublished. The structures of all compounds were established on the basis of their spectral data and mass analysis. The attractive features of this synthesis protocol include mild conditions, high atom-economy and excellent yields with the elimination of water as the only by-product.

2D-QSAR Studies on Phenoxybenzoic Acid Derivatives: A Novel Class of 5a-Reductase Inhibitors

The quantitative structure-activity relationship （QSAR） of 14 phenoxybenzoic acid derivatives was studied by ab initio method at the HF/6-31G level using Guassian03 software. The optimized structures together with some characteristic and electric parameters of the title compounds were obtained; some stereo-parameters were calculated by HyperChem software. Stepwise multiple regression and principal component regression methods are adopted to establish multi-parametric models between biological activity and parameters. The results indicated that the lager Ehomo, M, V and LogP, the smaller Etumo and S, and the higher biological activity. A theoretical direction was provided to synthesize some compounds with high activity.

An efficient way to coupling amine with derivatives of steric N-Boc-pyrrolidine-2-carboxylic acid

An efficient way to coupling amine with the derivatives of steric N-Boc-pyrrolidine-2-carboxylic acid was reported in this paper. We have found that the synthesis of derivatives is problematic with the commonly used DCC/HOBT method. As a substitute, the mixed anhydride method was adopted. A series of 6-（3-nitroguanidino）hexanamidopyrrolidine derivatives were prepared with this method.

Synthesis, Crystal Structure and Biological Activity of 6-Arylmethyl-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one Derivatives as Antitumor Agents

In order to explore the novel anti-tumor agents,ten 6-arylmethyl-3-aryl-777-thiazolo[3,2-b],2,4-triazin-7-ones were designed and synthesized,and the structures were characterized by ^1H-NMR,MS,IR and X-ray single-crystal diffraction analysis.The biological activity results showed that the target compounds exhibited certain inhibitory activity of osteosarcoma cells U2OS-EGFP.Compounds 6a,6g and 6j exhibited more than 70%inhibition ratio at the concentration of 50μmol·L^-1,and especially,the IC5o value of compound 6j was 11.58μmol·L^-1.The crystal of 6h was obtained and analyzed;some related weak interactions were discussed.The molecular docking results showed that the target compounds were supposed to be ERK1/2 inhibitors.

Synthesis,Crystal Structure and Biological Activity of 2-[(Pyridin-2-yl)methylthio]-1H-benzimidazole Derivatives

In order to discover the novel anti-tumor agents, a series of 2-[（pyridin-2-yl）methylthio]-1 H-benzimidazole derivatives were designed and synthesized, and the structures were characterized by IR, MS, and proton NMR. 2-[（3,4-Dimethoxypyridin-2-yl）methylthio]-1 Hbenzimidazole was investigated with X-ray crystallography, and the molecule is in orthorhombic system, space group P212121, with a = 9.1828（16）, b = 11.625（2）, c = 13.463（2） ？, Z = 4, R = 0.0231 and wR = 0.0596. The antitumor activities of target compounds were evaluated against human liver cancer cell line HepG2, and human liver normal cell line HL7702 using MTT assay. The target compounds have demonstrated weak or moderate anti-tumor activity against HepG2, while all the target compounds exhibit no cytotoxic effects on HL7702.

Big Third-order Nonlinear Optical Properties of Two Poly[(3-alkylthiophene-2, 5-diyl)-(benzylidenequinomethane-2, 5-diyl)] Derivatives

Two novel poly[(3-alkylthiophene-2,5-diyl)-(benzylidenequinomethane-2,5-diyl)s] derivatives, poly[ (3-butylthiophene-2,5-diyl)-( p-N,N-dimethylamino) benzylidenequinomethane-2,5-diyl) ] ( PBTDMABQ) and poly [( 3-octylthiophene2,5-diyl) -(p-N, N-dimethylamino ) benzylidenequinomethane-2, 5-diyl)] (POTDMABQ), were synthesized.The band gaps of the two polymers are calculated as 1. 75 eV for PBTDMABQ and 1. 69 eV for POTDMABQ,respectively. The homogenous films of the two polymers were prepared and their third-ordernonlinear optical properties were studied by the backward degenerate four-wave mixing at 532 nm. Byusing the relative measurement technique, the third-order nonlinear optical susceptibilities ofPBTDMABQ and POTDMABQ are calculated as 5. 62 X 10^(-9) and 1. 22 X 10^(-8) ESU, respectively. It isfound that substituted alky groups have strong effects on the band gap and nonlinear opticalproperties of the two polymers. The relatively big third-order nonlinear optical susceptibilitiesand small band gap of POTDMABQ resulted mainly from the longer alkyl with strong electron-donatingability can enhance the delocation degree of conjugated π electronics.

A Facile Synthesis of 9,10-Dimethoxybenzo[6,7]- ox-epino[3,4-<i>b</i>]quinolin-13(6<i>H</i>)-one and Its Derivatives

A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.

Solar Thermochemical Reactions IV: Unusual Reaction of Nitrones with Acetonitrile Derivatives Induced by Solar Thermal Energy

The behaviour of cyanothioacetamide 1 and the acetonitrile derivatives 6 and 10, respectively, towards the nitrones 2a-i induced by free solar thermal energy is reported. Structures and reaction mechanisms are also discussed.

NEW SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF

Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the isomerization of butenes at 273K. and the activity increasedwith the pre-treatment temperature up to 923K.

Theoretical Study on Two C_(16)H_(12)O_4 Isomers of Derivatives of Pagodane

Two C16H12O4 isomers of derivatives of pagodane were firstly reported and studied by using DFT method. Geometries, energies, and vibrational frequencies have been calculated for the two C16H12O4 isomers with pagodane-like structures at the B3LYP/6-31G^＊＊ level of theory. Symmetries of isomer 1 and 2 are D2h and D2d, respectively. Heats of formation for the two C16H12O4 isomers have been estimated in this paper. According to the heats of formation, the two C16H12O4 isomers are more stable than pagodane. Heats of formation as well as the vibrational analysis indicate that the two C16H12O4 isomers enjoy sufficient stability to allow for the experimental preparation.

A new pyrrolidone derivative from Pistacia chinensis

A new N-phenyl-pyrrolidone derivative had been isolated from Pistacia chinesis Bunge. Its structure was elucidated as 4-hydroxy-5-（2-oxo-1-pyrrolidinyl）-benzoic acid, named pistaciamide on the basis of the 1D-NMR, DEPT, HMQC and HMBC spectroscopic techniques. 2007 Xi Kui Liu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Asymmetric Synthesis and Crystal Structure of a Bioactive Morpholine Derivative

A novel morpholine derivative was synthesized by Michael addition/internal nucleophilic substitution of 4-（L）-menthyloxy（1R,2S,5R）-butenolide with phenyl-glyalcohol under mild condition, and its structure was determined by X-ray diffraction. The target compound belongs to orthorhombic, space group P212121 with a = 5.7729（7）, b = 11.5032（14）, c = 25.161（3）A, Mr = 319.35, Z = 4, V = 1670.8（4）A^3, Dc = 1.270 g/cm3, μ（MoKα） = 0.094 mm^-1, F（000） = 680, Flack = 0.01（2）, R = 0.0398 and wR = 0.0914.

Crystal Structure,Photoluminescence and Theoretical Studies of Diethyl 4,5-di(thienyl)-3,6-bis(trimethylsilyl)phthalate

The crystal structure of the title compound, diethyl 4,5-di（thienyl）-3,6-bis（trime- thylsilyl）phthalate （C26H3404S2Si2, Mr = 530.83）, has been determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pccn with a = 43.008（5）, b = 10.9000（12）, c = 11.9357（14） A, V= 5595.3（11） A3, Z = 8, F（000） = 2256, Dc= 1.260 mg/m3, p = 0.305 mm-1, T = 113（2） K, S = 1.090, R = 0.0413 and wR = 0.0969 for 5952 observed reflections with 1 〉 2o（/）. The benzene ring system is planar and makes dihedral angles of 63.7（2） and 72.5（4） with the two thienyl rings A （C（23）-C（26）, S（2）） and B （C（19）-C（22）, S（1））, respectively. The UV-vis absorption and fluorescence of the title compound were discussed. The molecular structure of the title compound has been optimized using DFT method at the B3LYP/6-31G（d） level. The computational results showed that the optimized geometer parameters are consistent well with the experiment data. The vertical ionization potential, vertical electron affinity and frontier orbitals were also discussed.

1,5-Dimethy-4-[(3-nitro-benzylidene)-amino]-2-pheyl-1,2-dihydro-pyrazol-3-one

The title compound C18H16N4O3 （Mr = 336.35） has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. The Schiff base compound is a derivative of 4-aminoantipyrine. As expected, the molecular structure adopts a trans configuration about the central C=N double bond. It crystallizes in orthorhombic, space group P2dc with a = 7.632（1）, b = 7.816（1）, c = 28.082（5） A,β = 96.18（1）°, V= 1665.48（51） A^3, Z= 4, Dc = 1.341 g/cm^3, F（000） = 704,μ = 0.094 mm^-1, the final R = 0.0448 and wR = 0.1058. Of the total 3748 collections, 3105 were unique. In the molecule there exist two different planes of pyrazoline and C（11）-C（16） phenyl ring, which are approximately coplanar （r.m.s. de deviation from the combined mean plane is 0.03 A） with the dihedral angle between them of 9.8%.

Synthesis,Structural Characterization and Properties of Bis(1,5-diamino-1Htetrazolium)3,3'-bis(nitramino)-4,4'-azofurazan

An energetic salt of bis（l,5-diamino-lH-tetrazolium）3,3＂-bis（nitramino）-4, 4x-azo- furazan （C6H10N2206） was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan （DAF） as the starting material. The structure of the title compound was confirmed by NMR, IR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in orthorhombic, space group P21/c with a = 10.739（2）, b = 6.4765（12）, c = 14.138（3） A, fl= 108.787（3）°, V= 930.9（3） A3, Z = 1, Mr= 486.36, Dc = 1.735 g.cm3, μ= 0.15 mm-1, F（000） = 496, R = 0.042 and wR = 0.121. The thermal stability was analyzed by subsequently differential scanning calorimetry （DSC）. And the enthalpy of formation and detonation was calculated theoretically, showing the first decomposition temperature was 142.1℃, the enthalpy of formation was 1614.23 kJ.mol1 and the detonation velocity and detonation pressure were 8.781 km.s-1 and 30.7 GPa, respectively.

New Thymol Derivate from Centipeda minima

1 Introduction Centipeda minima（Compositae） is an annual herbaceous plant found in moist places throughout the plains mainly in the southern regions of the People＇s Republic of China, Eastern tropical Asia, Australia and the Pacific Islands. It is a commonly used Chinese folk medicine for colds, whooping cough, nasal allergy, malaria and asthma. A number of sesquiterpene lactones, flavonoids and triterpenes have previously been isolated from C. minima. During our study on searching for biological active components from this plant,

Decreased serum platelet derived growth factor BB levels in acute and increased in chronic pancreatitis

AIM: To examine circulating growth factor concentrations in patients with acute pancreatitis (AP) and chronic pancreatitis (CP), and walled-off pancreatic necrosis (WOPN).

Synthesis and Crystal Structure of 2,6-Bis(2-pyridinylmethyl)-3,5-bis(2-hydroxyl-5-chlorophenyl)pyrazine

The title compound,2,6-bis（2-pyridinylmethyl）-3,5-bis（2-hydroxyl-5-chlorophe nyl）-pyrazine（C26H12Cl2N4O2C2H8O2,Mr=551.41）,has been synthesized and characterized by LC-ESIMS,NMR,UV and IR spectroscopy as well as by X-ray single-crystal diffraction.The compound behaves as a substituted pyrazine.The hydrogen atoms on C（2） and C（3） are substituted by 2-pyridinyl,whereas those on C（1） and C（4） are substituted by 2-hydroxyl-5-chlorophenyl.It crystallizes in the monoclinic system,space group P21/c with a=8.9433（12）,b=32.003（4）,c=10.5209（18）,β=111.199（2）°,V=2807.5（7）3,Z=4,Dc=1.305 mg/m3,F（000）=1144 and μ=0.094 mm-1.A total of 13235 reflections were collected in the range of 2.17～25.01o by using a phi and omega scan mode,of which 4923 were unique（Rint=0.0692） and 2872 observed reflections with Ⅰ 〉2σ（Ⅰ） were used in the structure solution and refinement.