Synthesis, Bioactivity, and Crystal Structure Analysis of 2-(3-Oxobenzo[d]isothiazol-2(3H)-yl)ethyl Benzoates

Fifteen novel 2-（3-oxobenzo[d]isothiazol-2（3H）-yl）ethyl benzoates were synthesi- zed by the condensation of 2-（2-hydroxyethyl）benzo[d]isothiazol-3（2H）-one with substituted benzoic acids in dichloromethane. All the compounds were characterized by elemental analysis, IR, ESI-MS and 1H NMR. The crystal structures for 2-（2-hydroxyethyl）benzo[d]isothiazol-3（2H）-one （2） and 2-（3-oxobenzo[d]isothiazol-2（3H）-yl）ethyl 2-methoxybenzoate （30） have been determined by X-ray crystal structure analysis. Compound 2 （C9H9NO2S） crystallizes in the monoclinic system, space group Pn with a = 10.552（3）, b = 7.849（2）, c = 10.765（4） A, β = 103.128（4）°, V= 868.3（5） A3, Mr = 195.24, Dc = 1.493 Mg.m-3, μ = 0.33 mm-1, F（000） = 408, Z = 4, R= 0.0314 and wR= 0.0628. Compound 30 （C17H15NO4S） crystallizes in the triclinic system, space group P1 with a = 8.028（2）, b = 9.300（2）, c = 10.430（3）A, V= 752.1（3）A3, Mr = 329.36, D,= 1.454 Mg.m-3, p = 0.24 mm-1, F（000） = 344, Z = 2, R = 0.0377 and wR = 0.0904. The preliminary biological test indicated that the title compounds show better growth inhibitory activity against the gram-positive bacteria than the gram-negative bacteria.

Spectral Properties and Solubilization Location of 2′-Ethylhexyl 4-（N,N-Dimethylamino）benzoate in Micelles

Dual fluorescence and UV absorption of 2′-ethylhexyl 4-（N,N-dimethylamino）benzoate （EHDMAB） were investigated in cationic, non-ionic and anionic micelles. When EHDMAB was solubilized in different micelles, the UV absorption of EHDMAB was enhanced. Twisted intramolecular charge transfer （TICT） emission with longer wavelength was observed in ionic micelles, whereas TICT emission with shorter wavelength was obtained in non-ionic micelles. In particular, dual fluorescence of EHDMAB was significantly quenched by the positively charged pyridinium ions arranged in the Stern layer of cationic micelles. UV radiation absorbed mainly decays via TICT emission and radiationless deactivation. The dimethylamino group of EHDMAB experiences different polar environments in ionic and non-ionic micelles according to the polarity dependence of TICT emission of EHDMAB in organic solvents. In terms of the molecular structures and sizes of EHDMAB and surfactants, each individual EHDMAB molecule should be buried in micelles with its dimethylamino group toward the polar head groups of different micelles and with its 2′-ethylhexyl chain toward the hydrophobic micellar core. Dynamic fluorescence quenching measurements of EHDMAB provide further support for the location of EHDMAB in different micelles.

Synthesis and anti-inflammatory-analgesic activity of 2',4'-difluoro-3-(carbamoyl)biphenyl-4-yl benzoates

Eighteen 2′,4′-difluoro-3-（carbamoyl）biphenyl-4-yl benzoates were synthesized from diflunisal in three steps with total yields from 72% to 86%. All compounds were identified by IR, 1^H NMR, MS and elemental analysis. The anti-inflammatory activity and analgesic activity for 18 compounds were evaluated. The preliminary assay results showed that compounds 4a and 4p exhibited potent anti-inflammatory-analgesic activity.

Synthesis and Crystal Structure of Tert-butyl 4-[(E)-4-(1,3-Dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-butenyl] Benzoate

The title compound tert-butyl 4-[（E）-4-（1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl）- 1-butenyl] benzoate has been synthesized and characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 14.875（3）, b = 8.9796（13）, c = 34.736（6） A°, β = 95.981（4）°, V= 4614.4（14）A°^3, Z= 8, Dc = 1.213 g/cm^3, F（000） = 1792,μ（MoKα） = 0.084 mm^-1, R = 0.0602 and wR = 0.1445 for 4613 unique reflections with 2272 observed ones （I〉 2σ（I））. The results of crystal structure determination show that the title compound has a layer structure, and the two benzene rings in molecule are parallel to each other.

Synthesis, Structure and Photocatalytic Activity of Two 4-(2,6-Di(pyrazin-2-yl)pyridin-4-yl)benzoate-Based Chain Complexes

Two new one-dimensional chains extended by alternate benzenedicarboxylate（BDC） and 4-（2,6-di（pyrazin-2-yl）pyridin-4-yl）benzoate（L-） connectors, {[Cu（L）（BDC）（0.5）]·3.5 H2 O}n （1） and {[Zn（L）（BDC）（0.5）] ·H2 O}n （2）, were solvothermally synthesized. Complex 1 is in triclinic system, space group P1 with a = 9.6456（14）, b = 11.1160（16）, c = 12.0414（18） A, α = 106.266（3）, β = 92.277（3）, γ =108.104（3）°, V = 1166.6（3） A3, Dc = 1.603 g·cm（-3）, Mr = 563.00, Z = 2, F（000） = 578, μ = 0.996 mm（-1）, the final R = 0.0575 and wR = 0.1386 for 3704 observed reflections with I ＆gt; 2σ（I）. Complex 2 crystallizes in monoclinic, space group C2/c with a = 28.607（5）, b = 8.9767（16）, c = 19.705（4） ？, β = 125.396（3）°, V = 4125.0（13） ？3, Dc = 1.674 g·cm（-3）, Mr = 519.79, Z = 8, F（000） = 2120, μ = 1.242 mm（-1）, the final R = 0.0487 and w R = 0.0907 for 2944 observed reflections with I ＆gt; 2σ（I）. Resulting from the narrower band gap and broader response to visible light, the CuII-chain exhibits better photocatalytic performance towards the degradation of rhodamine B and methylene blue than those of ZnII-chain.

SYNTHESIS AND CHARACTERIZATION OF POLY{4-[2-(tert-BUTYLDIMETHYLSILOXY)ETHYL]STYRENE}AND ITS HYDROLYSIS DERIVATIVE

The living cationic polymerization of 4-[2-(tert-butyldimethylsiloxy)ethyl]styrene (TBDMES) was studied in methylcyclohexane (MeChx)/methylchloride (MeCl) (50/50 V/V) solvent mixture at -80 degrees C. The initiator 1,1-diphenylethylene (DPE) capped 2-chloro-2,4,4-trimethylpentane (TMPCl) was formed in situ in conjunction with titanium tetrachloride (TiCl(4)). The Lewis acidity of TiCl(4) was decreased by the addition of titanium(IV) isopropoxide (Ti(OiPr)(4)) to accomplish living polymerization of TBDMES. Hydrolysis of poly(TBDMES) in the presence of tetra-butylammonium fluoride yielded poly[4-(2-hydroxyethyl)styrene] (poly(HOES)). FT-IR, NMR and DSC demonstrated the hydrolysis was complete.

4-(5-氨基-6-羟基-2-苯并噁唑基)苯甲酸的合成

系统地研究了AB型新单体:4-(5-氨基-6-羟基-2-苯并噁唑基)苯甲酸(ABA)的合成方法以及产品析出时pH值条件对其分子形态及红外吸收的影响。以4-(5-氨基-6-羟基-2-苯并噁唑基)苯甲酸甲酯(MAB)为原料,60～100℃于碳酸钾水溶液中水解反应至溶液澄清,用还原性弱酸性盐的水液在pH值6.0析出结晶、制得纯度99.5%以上高质量的新单体、经FT-IR归属剖析确认为游离的酸式单体ABA,收率达85%;具有过程工艺简便,单体稳定性优异、且无残留DMF阻聚杂质以及聚合操作安全等特点,在制备聚合级AB型PBO单体中取得新进展。

2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯的合成探索

以4,5-二硝基邻苯二胺和2-羟基对苯二甲酸单甲酯为起始原料,设计并成功采用一锅法合成出2-羟基-4-(5,6-二硝基-1H-苯并[2,3-d]咪唑-2-基)苯甲酸甲酯(MHDIB)。以50 mL二乙二醇二甲醚为溶剂,1.5 g的2-羟基对苯二甲酸单甲酯和2.5 g SOCl2在80℃反应2 h制2-羟基-4-氯羰基苯甲酸甲酯。室温下快速向反应体系中加入1.56 g 4,5-二硝基邻苯二胺,并于85℃反应1 h后加入3.52 g多聚磷酸,回流反应1 h后水析出粗产品,经乙醇重结晶得到纯度为93.67%的黄色针状产物,产率为17.82%。产物经IR、MS、1H NMR的准确定性和表征,作为AB型新单体的前体可应用于羟基改性PBI纤维即聚2-羟基-1,4-亚苯基-2,6-苯并[2,3-d:5',6'-d']二咪唑(H-PBI)的创新研究。

Effect of Chemical Doping and Ion Implantation on Cond uctivity of Poly(p-phenylene vinylene) Derivatives

The surface conductivity of poly [ 2-methoxy-5-（3＇-methyl） butoxy]-p-phenylene vinylene （PMOMBOPV） films doped with FeCl3 and H2SO4 by chemical method and implanted by N^＋ ions was studied and the comparison of environmental stability of conductive behavior was also investigated. The energy and dose of N^＋ ions were in the rang 15～35 keV and 3. 8×10^15～9. 6×10^16 ions/cm^2, respectively. The conductivity of PMOMBOPV film was enhanced remarkably with the increases of the energy and dose of N^＋ ions. For example, the conductivity of PMOMBOPV film was 3. 2×10^-2S/cm when ion implantation was performed with an energy of 35 keV at a dose of 9. 6 × 10^14 ions/cm^2 , which was almost seven orders of magnitude higher than that of film unimplanted. The environmental stability of conductive behavior for ionimplanted film was much better than that of chemical doped films. Moreover, the conductive activation energy of ion-implanted films was measured to be about 0.17 eV.

SYNTHESIS,CHARACTERIZATION AND ANTIMICROBIAL PROPERTIES OF 4-[(4-HYDROXYBENZYLIDENE)AMINO]PHENOL AND ITS POLYMER

The oxidative polycondensation reaction conditions of 4-[（4-hydroxybenzylidene） amino] phenol （4-HBAP） were studied with H2O2, air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃. The structures of the obtained monomer and polymer were confirmed by FT-IR, UV-Vis, 1H- and 13C-NMR and elemental analysis. The characterization was made by TG-DTA, size exclusion chromatography （SEC） and solubility tests. At the optimum reaction conditions, the yield of poly[4-（4-hydroxybenzylidene amino） phenol] （P-4-HBAP） was found to be 48.3% （for H2O2 oxidant）, 80.5% （for air O2 oxidant） and 86.4% （for NaOCl oxidant）. According to the SEC analysis, the number-average molecular weight （Mn）, weight-average molecular weight （Mw） and polydispersity index （PDI） values of P-4-HBAP was found to be 8950, 10970 g tool^-1 and 1.225, respectively, using H202; and l l610, 15190 g tool^-1 and 1.308 respectively, using air 02 and 7900, 9610 g mol^-1 and 1.216, respectively, using NaOC1. According to TG-DTA analyses, P-4-HBAP was more stable than 4-HBAP against thermal decomposition. The weight loss of P-4-HBAP was found to be 49.27% at 1000℃. The highest occupied molecular orbital （HOMO） and the lowest unoccupied molecular orbital （LUMO） values calculated from electrochemical measurement. Electrochemical energy gaps （Eg＇） of 4-HBAP and P-4-HBAP were found to be -5.46, -5.28; -2.26, -2.67; 3.20 and 2.61 eV, respectively. According to UV-Vis measurements, optical band gap （Eg） of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV, respectively. Also, antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria. The electrical conductivity of the polymer was measured after doping with iodine.

Two 2-(quinonylcarboxamino)benzoates from the lateral roots of Aconitum carmichaelii

Two new 2-（quinonylcarboxamino）benzoates, named aconicarmiquinamides A （1） and B （2）, were isolated from an aqueous extract of the lateral roots of Aconitum carmichaelii. Their structures were determined by spectroscopic data analysis, and confirmed by comparison with synthetic methyl 3.6- bis（ diethylamino ）benzoqunonylcarboxylate （3）.

溶胶-凝胶法制备纳米TiO_2-ZrO_2/Poly(MMA-co-MSMA)复合材料

以钛酸异丙酯（Ti（OPri）4）、锆酸正丁酯（Zr（OC4H9）4）为无机前驱物原料,γ-甲基丙烯酰氧基丙基三甲氧基硅烷（MSMA）为偶联剂,通过原位溶胶-凝胶法成功制备了透明的纳米TiO2-ZrO2/Poly（MMA-co-MSMA）复合材料。通过红外（FTIR）、紫外（UV）、椭圆偏振光谱仪、扫描电镜（SEM）和热重分析仪（TGA）等手段对纳米复合材料进行了表征。研究发现,复合材料的折射率显著提高,随着TiO2-ZrO2无机氧化物含量的增加,633 nm处折射率从1.491升高到1.579。随着无机组分的增加,紫外吸收增强,复合材料中纳米粒子粒径增大,从20~30nm增加到80~90 nm,但复合材料块体始终保持透明。复合材料的热稳定性有明显提高,800℃最高残炭率随着无机物含量的增加而增大,最高达71%。

Functional Amphiphilic Poly(2-oxazoline)Block Copolymers as Drug Carriers:the Relationship between Structure and Drug Loading Capacity

Poly(2-oxazoline)(POx)is a kind of polymeric amides that can be viewed as conformational isomers of polypeptides with excellent cyto-and hemo-compatibility,and is promising to be used as drug carriers.However,the drug loading capacity(DLC)of POx for many drugs is still low except several hydrophobic ones including paclitaxel(PTX).Herein,we prepared a series of amphiphilic POx block copolymers with various functional groups,and investigated the relationship between functional structures and the DLC.Functional POxs with benzyl,carboxyl,and amino groups in the side-chain were synthesized based on a poly(2-methyl-2-oxazoline)-block-poly(2-buty1-2-oxazoline-co-2-buteny1-2-oxazoline)(PMeOx-P(nBuOx-co-ButenOx),PMBEOx)precursor,followed by click reaction between vinyl and the 2-phenylethanethiol,thioglycolic acid and cysteamine.Using thin-film hydration method,eight commonly used drugs with various characteristics were encapsulated within these functional POx polymers.We found that amine-containing drugs were more easily encapsulated by POx with carboxyl groups,while amine functionalities in POx enhanced the loading capacity of drugs with carboxyl groups.In addition,n-n interactions resulted in enhanced DLC of most drugs,except several hydrophobic drugs with aromatic to total carbon ratios less than 0.5.In general,we could successfully encapsulate all the selected drugs with a DLC%over 10%using properly selected functional POxs.The above results confirm that the DLC of polymeric carriers can be adjusted by modifying the functional groups,and the prepared series of functional POxs provide an option for various drug loadings.

Poly[β-(1→4)-2-amino-2-deoxy-D-glucopyranose] based zero valent nickel nanocomposite for efficient reduction of nitrate in water

Chemical reduction of nitrate using metal nanoparticles has received increasing interest due to over-dependence on groundwater and consequence health hazard of the nitrate ion. One major drawback of this technique is the agglomeration of nanoparticles leading to the formation of large floes. A low cost biopolymeric material, poly [β-（1-4）-2-amino-2-deoxy-D-glucopyranose] （β-PADG） obtained from deacetylated chitin was used as stabilizer to synthesize zero valent nickel （ZVNi） nanoparticles. The β-PADG-ZVNi nanocomposite was characterized using infra red （IR）, UV-Vis spectrophotometric techniques and Scanning Electron Microscope （SEM）. The morphology of the composite showed that β-PADG stabilized-ZVNi nanoparticles were present as discrete particles. The mean particle size was estimated to be （7.76 ± 2.98） nm and surface area of 87.10 m2/g. The stabilized-ZVNi nanoparticles exhibited markedly greater reactivity for reduction of nitrate in water with 100% conversion within 2 hr contact owing to less agglomeration. Varying the β-PADG-to-ZVNi ratio and the ZVNi-to-nitrate molar ratio generally led to a faster nitrate reduction. About 3.4-fold difference in the specific reaction rate constant suggests that the application of the β-PADG-stabilizer not only increased the specific surface area of the resultant nanoparticles, but also greatly enhanced the surface reactivity of the nanoparticles per unit area.

Investigation of Intrachain Exciton Diffusion of MEH-PPV in Solution with Different Polarity

Femtosecond time-resolved transient grating technique was adopted to insight into the intra-chain exciton diffusion of MEH-PPV in solution with different polarity. Broadband white-light continuum was introduced as the probe to observe the transient absorption and the femtosecond time-resolved transient grating information simultaneously. The vibrational dephasing behaviors, single exciton relaxation, and population relaxation dynamics of MEH-PPV were systematically investigated. The result shows that the relaxation processes of the sample solution will be accelerated in the solvent with larger polarity.

Charge Transfer Properties in MEH-PPV/PS:MWCNTs Nanocomposites

The effect of composition and annealing temperature on charge transfer properties, in a donor/acceptor nanocomposites based on poly (2-methoxy-5-(2-ethyhexyl-oxy)-p-phenylenevinylene) (MEH-PPV) and MWCNTs functionalized with Polystyrene (PS:MWCNTs), have been investigated. The quenching of photoluminescence (PL) intensity of pure MEH-PPV, by adding different amounts of functionalized carbon nanotubes, exhibits that a photoinduced charge transfer has been occurred. Charge transfer efficiency was obtained for an acceptable concentration of PS:MWCNTs about 0.5 wt% and at annealed temperature of about 80℃. Quenching efficiency studies imply that MEH-PPV/PS:MWCNTs nanocomposites reveal a high degree of PL quenching, reaching a value of η = 76.9%.

Poly （ADP-ribose） polymerase inhibitor reduces heart ischaemia/ reperfusion injury via inflammation and Akt signalling in rats

Background Poly （ADP-ribose） polymerase （PARP） has been proposed to play an important role in the pathogenesis of heart ischaemia/reperfusion （I/R） injury. 3,4-dihydro-5-[4-（1-piperidinyl）butoxy]-l（2H）-isoquinolinone （DPQ）, a potent PARP inhibitor, has cardiac protective effects. Because the underlying mechanisms are not understood, we investigated the effect of DPQ on heart I/R injury and its mechanisms. Methods Studies were performed with I/R rats＇ hearts. DPQ was used to inhibit the activation of PARP. Cardiac function and cellular apoptosis were assessed. The activation of PARP, transcription factor nuclear factor-kappaB （NF-KB）, intercellular adhesion molecule-1 （ICAM-1）, cyclooxygenase-2 （COX-2） and matrix metalloproteinase-9 （MMP-9） were evaluated. We also evaluated expression of Akt and two of its downstream targets, glycogen synthase kinase-313 （GSK- 3β） and forkhead transcription factor FOXO3a. Results Administration of DPQ significantly decreased the activation of PARP and cellular apoptosis from （35±5）% to （20±4）% and simultaneously improved the cardiac function. DPQ reduced the expressions of NF-KB, ICAM-1, COX-2 and MMP-9 in rat heart and facilitated the activations of phosphor-Akt, phosphor-GSK-3β and phosphor-FOXO3a. Conclusion The protective effects of DPQ were associated with the suppression of inflammation and the activation of the Akt signalling pathways suggesting that the inhibition of poly （ADP-ribose） polymerase reduced heart I/R injury in rats.

Synthesis and characterization of poly(p-dioxanone)-based degradable copolymers with enhanced thermal and hydrolytic stabilities

Herein, we presented a novel biodegradable copolymer via the chain extending reaction of poly(pdioxanone)-co-poly(2-(2-hydroxyethoxy) benzoate)(PPDO-co-PDHB) prepolymer with hexamethylene diisocyanate(HDI) as a chain extender. The structures and molecular weight of PPDO-co-PDHB prepolymer and PPDO-co-PDHB-PU chain-extended copolymer are characterized via hydrogen nuclear magnetic resonance spectroscopy(1 H NMR) and viscosity test. The relationship between the molecular structures and properties of the chain-extended copolymers is established. The PPDO-co-PDHB-PU copolymers possess a better thermal stability comparing with the PPDO homopolymer. The study of mechanical properties shows that the elongation-at-break of PPDO-co-PDHB-PU is much higher than that of PPDO. The investigation of hydrolytic degradation behaviors indicates the degradation rate of PPDO can be controlled by adjusting the PDHB compositions, and proves that chain-extended copolymers exhibit an excellent hydrolytic stability being better than that of PPDO.

SYNTHESIS OF A NOVEL CHELATING RESIN WITH HETEROCYCLIC RING OF S AND N

By the reaction of poly(bromoacetyl styrene) (EBPS) with thiaurea (TU), a kind of novel chelating resin with heterocyaclic ring of sulfur and nitrogen, poly[4-(2-amino)thiazoleyl-4- vinylbenzene], was synthesized. Its structure was characterized by FTIR and elemental analysis. The factors which have influence on the reaction such as reaction time, solvents, and molar ratio of reactants were investigated.

The Influence of Aziridine on the Aging of Composite Solid Rocket Propellant

Aging of a solid composite propellant containing HTPB/AP/AL was performed in order to validate the conformance of the accelerated aging data to the Arrhenius law. The main objective of the work was to examine the influence of the aziridine bonding agents family on the propellant aging. Aging of the prepared propellant samples was conducted as follows: 1. Four samples, one free of bonding agents, and three containing aziridine based bonding agents MAPO,HX-752, MAT4 were aged at 65°C. 2. Another four samples based on HX-752, MAT4 with different curing agents were aged at 65°C. The measured mechanical properties of the free bonding agent propellant samples were very far from the specifications and this illustrates the importance of the bonding agents in both the preparation and the aging phases.The prepared bonding agent 'MAT4' gave remarkable improvements of the mechanical properties comparing with HX-752 and MAPO. The aziridine bonding agents family inhibited the rate of decomposition of the propellant during the aging periods and supported the propellant matrix against decomposition at the elevate temperatures. Using of HMDI as curing agent gave slight better mechanical properties to the IPDI.