KINETICS AND MECHANISM OF PHOTOINDUCED POLYMERIZATION BY α,α-DIMETHOXY-α-PHENYL ACETOPHENONE

α,α-dimethoxy-α-Phenyl acetophenone (DMPA) is an efficient and thermally stable photoinitiator. Here its spectral characteristics in the transient state were shown. The transient species were identified as a benzoyl radical and a dimethoxyi benzyl radical that played a primary initiation role in polymerization. The kinetics and mechanism of the bulk polymerization of MMA were investigated. The exponent of DMPA concentration and k_p/k_1^(1/2) value were found to be 0.5 and 0.066 mol(-1/2)l^(1/2)s^(-1/2), respectively. The existence of oxygen led to obtain the polymer with higher molecular weight, which can be attributed to the occurrence of the subsequent polymerization induced by active polymer end group. In the photocrosslinking reaction, the dependence of DMPA content on initial rate has been found. A principal reason is that the sample contained higher percentage of DMPA has higher light-absorbed efficiency. In solid film, higher concentration of DMPA is permitted to be used because there is little excited state self-quenching effect in the rigid medium.

Protective Effect of Dimethyl-4,4'-Dimethoxy-5,6,5',6'-Dimethylene Dioxybiphenyl-2,2'-Dicarboxylate (DDB) against Carcinogen-Induced Rat Liver Nuclear DNA Damage

The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (a) pyrene to nuclear DNA. Unscheduled DNA synthesis (UDS) induced by aflatoxin BI (10^(-7) mol.L-1) in freshly isolated rat hepatocytes was also inhibited by DDB (10^(-6)-10^(-3)mol.L-1). Oral administration of DDB at 200 mg.kg-1 once daily for 3 d induced a significant increase of liver cytosol glutathione-S-transferase and microsomal UDPG-transferase activity in mice. These results indicate that DDB is able to directly or indirectly antagonize certain carcinogen-induced DNA damages.

Protective Effects of Dimethyl-4,4'-Dimethoxy-5,6,5',6'-Dimethylene Dioxybiphenyl-2,2'-Dicarboxylate on Damages of Isolated Rat Hepatocytes Induced by Carbon Tetrachloride and D-galactosamine

The protective effect of biphenyl dimethyl dicarboxylate (DDB) on chemically induced damages was studied in isolated suspended rat hepatocytes. The experimental results showed that DDB (200μg/106 cells) efficiently protected the hepatocytes against carbon tetrachloride (CC14 10 mrnol.L-1) and D-galactosamine (1 mmol.L-1) induced damages. Membranal lipid peroxidation (malondialdehyde, MDA formation) and glutamic pyruvic transaminase (GPT) release from the hepatocytes were markedly decreased. The damage of the cell surfaces of the hepatocytes were also reduced as seen under a scanning electron microscope (SEM). Pretreatment with DDB (300 mg-kg-1) orally ameliorated the reduction of liver glycogen and blood glucose caused by ip injection of D-galactosamine (800 mg-kg-1) in mice. When normal rats were given DDB 300 mg-kg-1 once daily for 10 d, the free ribosomal protein and RNA in the liver increased significantly. These results indicate that DDB is of beneficial effects on both damaged and normal hepatocytes.

Synthesis and Molecular Structure of (E)-1- (Morpholino)-2-(thiomethyl)-2-phenylvinylphosphonate

The title compound 2 (C15H22NO4PS, Mr = 343.38) was prepared by the reaction of α-benzoylthioformmorpholine 1 with trimethyl phosphite. The crystal is of monoclinic, space group P21/c with a = 14.906(2), b = 8.4711(12), c = 13.343(2) ?, β = 96.761(4)o, Z = 4, V = 1673.1(5) ?3, Dc = 1.363 g/cm3, μ(MoKα) = 3.06 cm-1, F(000) = 728, the final R = 0.0590 and wR = 0.1740 for 3036 observed reflections (I > 2σ(I)). X-ray analysis revealed that the interatomic distance of C(5)–C(6) is 1.353(4) ?, indicating it is a normal C=C double bond. The P(1) atom takes a distorted tetrahedral geometry, and the morpholine ring adopts a chair conformation. The morpholino group is located at the 1-position of vinylphosphonate, and the phenyl and thiomethyl groups at the 2-position.

An Efficient Process for Preparing 4-Methyl-2-phenyl Piperazine Hydrochloride and its Derivatives

An improved method for preparation of 4-methyl-2-phenyl piperazine and its derivatives with higher yield and inexpensive reagents was developed, the products were characterized by 1H-NMR and MS.

Synthesis and Crystal Structure of Salicylyl-4-phenyl Thiosemicarbazide Lead with a Two-dimensional Network

A two-dimensional lead complex, [Pb（C14N3O2H12S）（NO3）]n·nH2O, was prepared by the reaction of salicylyl-4-phenyl thiosemicarbazide and lead nitrate. The compound （C14H13N4O6PbS, Mr = 572.53） crystallizes in the monoclinic space group P21/c with a = 11.2984（2）, b = 15.6628（7）, c = 11.1118（2）A,β= 113.564（2）°, V = 1802.43（10）A3, Dc= 2.110 g/cm3, Z = 4,μt（MoKα） = 9.515 mm-1, F（000） = 1084, the final R = 0.0394 and wR = 0.0701 for 2552 observed reflections with I 〉 2σ（I）. The Pb（Ⅱ） ion displays a distorted octahedron in which the hypothesized stereochemically active lone pair occupies the apex. The compound exhibits a two-dimensional network structure formed by the zigzag one-dimensional chains joined by two μ-O of two nitrate groups in overlapping. A large ring exists in the two-dimensional layers. The TGA of the title compound has been studied.

Growth inhibitory effect of 4-phenyl butyric acid on human gastric cancer cells is associated with cell cycle arrest

AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 μmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry.RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a doseand time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.

Photoluminescence and Electroluminescence Properties of 2,5-Bis[2,2′-bis(5-phenyl)-1,3,4-oxadiazole] Thiophene(T-OXD) and T-OXD/Poly(9-vinylcarbazole) Blends

The photoluminescence(PL) and the electroluminescence(EL) properties of a novel organic compound, 2,5-bis(2,2′-bis(5-phenyl)-1,3,4-oxadiazole(T-OXD), were studied in chloroform and in a solid thin film. The PL and the EL properties of T-OXD/poly(9-vinylcarbazole)(PVK) blends were also studied, which contained various contents of T-OXD. The PL maximum emission peaks of T-OXD/PVK blends show gradual bathochromtic-shift with the increase of the T-OXD content. The EL spectra of T-OXD/PVK devices are similar to their PL spectra, and all the EL maximum emission peaks show bathochromtic-shift compared with the corresponding PL spectra, which is ascribed to the formation of electroplex. The turn-on voltages for ITO/T-OXD:PVK/Al devices decreased from 13.5 V of the device cotaining 0.1% T-OXD(mass fraction) to 5 V of the device containing 5% T-OXD, which suggests that T-OXD improves the energy level match between T-OXD and PVK and enhances the emission efficiency. The experimental results indicate that T-OXD can be used as a good electron transporting material.

Synthesis, Crystal Structure and Quantum Chemistry of Tris[(2-methyl- 2-phenyl)propyl](2,4-dinitro-phenolato)tin

The tris[（2-methyl-2-phenyl）propyl]（2,4-dinitro-phenolato）tin was synthesized by the reaction of bis[tri（2-methyl-2-phenyl）propyltin] oxide with 2,4-dinitrophenol. The compound was characterized by IR, 1H NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 0.9649（0）, b = 1.0087（8）, c = 3.4867（4） nm, β = 90.965（7） , Z = 4, V = 3.3933（7） nm3, Dc = 1.369 Mg·m-3, （MoKa） = 0.796 mm-1, F（000） = 1440, R = 0.0345 and wR = 0.0821. The tin atom has a distorted tetrahedral geometry. The 2D network structure of the complex is formed by hydrogen bonds and π-π effects. The stabilities, orbital energies and composition characteristics of some frontier molecular orbitals of the complexes have been investigated with the aid of G98W software.

A Novel Fluorescence Probe 9-(4-(1,2-diamine)benzeneN^1-phenyl)acridine for Nitric Oxide Determination

A novel fluorescent probe 9-（4-（1,2-diamine）benzene-N1-phenyl）acridine（DABPA） was synthesized for the detection of nitric oxide（NO） and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelectron transfer mechanism, the fl uorescence intensities of DABPA were investigated with the different concentrations of NO. Under the optimal experimental conditions, the fl uorescence intensity of DABPA had a good linear relationship（R2=0.9977） with NO concentration in the range from 1×10-7 to 1.5×10-6 mol/L with a detection limit of 1×10-8 mol/L. The cytotoxicity induced by DABPA was evaluated by the MTT（3-（4,5-dimethylthiazol-2-yl）-2,5diphenyl tetrazolium bromide） assay for biological application. Furthermore, the probe DABPA had also been successfully applied to real-time image NO produced in PC12 cells in the presence of L-arginine.

采用大孔吸附树脂纯化发酵液中D-3-苯基乳酸

为从发酵液中分离纯化D-3-苯基乳酸(D-3-phenyl lactic acid,PLA),利用重组大肠杆菌E.coli p ET-28aldhY52V转化底物苯丙酮酸(phenylpyruvic acid,PPA)合成PLA,采用离子交换法对PLA纯化工艺进行了初步研究。通过对6种常用阴离子交换树脂对PLA的静态吸附容量测定,确定了D315具有较强的PLA吸附性能。在固定床上样条件优化结果表明,上样流速为4 BV/h、径高比为1∶7时,上样吸附效果较好。利用二阶段洗脱工艺:第一阶段用100 mmol/L HCl进行洗脱,第二阶段用200 mmol/L Na Cl在5 BV/h流速下洗脱。洗脱验证结果表明,第一阶段洗脱液中PLA/PPA的质量浓度比值由初始的4.2上升到10.3,PLA收率为66.4%。研究结果为进一步采用离子交换法纯化发酵液中PLA的工艺优化提供了借鉴。

Reactivity of 3-Cyanoacetylindole Derivatives: Synthesisof 3-Hydrazonopyrazolyl and 3-Thiadiazolyl Indole Derivatives

The coupling reaction of 3-cyanoacetyl-2-methylindole 1a with the aromatic diazonium salts gave the corresponding arylhydrazones 2a-e. Compounds 2 were used for synthesis of 4-aminopyrazole-5-carbonitrile 4a-e and 5-amino-4-arylazo-3-pyrazoles 5a-e derivatives. Also, treatment of 3-cyanoacetyl-2-phenylindole 1b with phenyl isothiocyanate gave the corresponding thioacetanilide 7. The later compound 7 was utilized as the key intermediate for the synthesis of some new thiadiazole derivatives 9a-r. The structures of all new compounds were elucidated on the basis of elemental analysis and spectral data.

Crystal Structure of Isoquinoline Derivatives

The chiral compound 5H-imidazol[2,3-b]isoquinoline-l-ethanol-5-one-1,2, 3, 10b-tetrahydro- β（S）-phenyl-3（S）-phenyl was synthesized from the direct condensation of 2- cyanophenyacetonitrile with optically active （S）-（＋）-2-phenylglycinol in chlorobenzene under dry, anaerobic conditions. ZnCl2 was used as a Lewis acid catalyst in this reaction, and the structure of this compound was determined by X-ray diffraction, NMR, MS and IR. Crystal data of the title compound： C25H22N2O2, Mr = 382.45, P 21 21 21, a = 5.341（5）, b = 16.735（5）, c = 22.129（5） A, γ = 90°, V = 1978（2）A^3, Z = 4, Dc = 1.284 g/cm^3, the final R = 0.0321 for 2269 observed reflections with I 〉 2 σ（I） and Rw = 0.0771 for all data.

A Phenolic Glucoside from Alangium plantanifolium

A novel phenolic glucoside was isolated from stem barks of Alangium plantanifolium, its structure was elucidated to be 1-O-[2-(1-hydroxy-6-oxocyclohex-2-ene-1-carboxymethyl) -phenyl]-4, 6-O-[(S)-4, 4', 5, 5', 6, 6'-hexahydroxydi-phenoyl]-beta -D-glucopyranose 1 by spectroscopic methods including 2D NMR techniques.

RESOLUTION OF RACEMIC DIMETHYL 4,4′-DIMETHOXY-5, 6, 5′, 6′-BISMETHYLENEDIOXYBIPHENYL-2, 2′-DICARBOXYLATE (BIPHENYL DIESTER) ——A NEW ANTIHEPATITIC DRUG

Synthetic biphenyl diester, dimethyl 4, 4’-dimethoxy-5, 6, 5′, 6′-bismethylenedioxybi-phenyl-2, 2′-dicarboxylate is a new antihepatitic drug. Pharmacological studies showed that biphenyl diester has relatively strong SGPT lowering activity. It has been used clinically for the treatment of chronic hepatitis and lowering the elevated SGPT caused by certain chemicals and medicaments. Owing to the presence of four ortho substituents on the 2, 2′ and 6, 6′position in the biphenyl skeleton, the molecule can exist in two atropisomers.

Potential anti-tubercular agents:Hexahydro-3-phenyl indazol-2-yl(pyridin-4-yl)methanones from anti-tubercular drug isoniazid and bis(substituted-benzylidene)cycloalkanones

A series of indazol-2-yl（pyridin-4-yl）methanones, 4 were acquired from 2,6-bisbenzylidene cyclohex- anones, 3 and anti-tubercular drug （isoniazid）, and their anti-tubercular impacts were screened. Among the test compounds used against Mycobacterium tuberculosis H37 Ra cell line in the microplate alamar blue assay, the compounds 4g-j revealed moderate anti-tubercular activity with MIC 12.5 μg/mL, comparable to standard drugs （streptomycin, MIC, 6.25 μg/mL, pyrazinamide, isoniazid and ciprofloxacin with MICs of 3.125 μg/mL）.

Catalytic dechlorination and detoxification of 1-(2-chlorophenyl) ethanol by Pd/Fe

1-(2-chlorophenyl) ethanol (CPE) is of health and environmental concern due to its toxicity and its use as an inter-mediate in pharmaceutical manufacturing. The current work deals with the catalytic reductive dechlorination and detoxification of CPE by Pd/Fe bimetal. CPE was effectively dechlorinated to 1-phenyl ethanol (PE) accompanied by the equivalent release of chloride. The extent of CPE dechlorination increased with temperature,Fe dosage and Pd loading. A decrease in solution pH increased CPE dechlorination,resulting presumably from an increase in hydrogen production. Under the specific conditions of 20 g/L Pd/Fe,0.10% Pd (w/w) and initial pH 5-6,the CPE dechlorination was completed within 145 min. The dechlorination fol-lowed a pseudo-first-order kinetics with an activation energy of 56.7 kJ/mol. The results of toxicity testing showed that CPE was very toxic to Chlorella,whereas PE showed little toxicity. The toxicity of the reaction solution declined gradually and the pro-moting effects on Chlorella intensified consequently with the dechlorination process. Thus,the reductive dechlorination of CPE to PE by Pd/Fe was a detoxification process. It may be used to effectively reduce the toxicological effects of CPE-contaminated wastewater,thereby enhancing the performance of subsequent biological processes in wastewater treatment.

Organic dyes containing fused acenes as building blocks： Optical, electrochemical and photovoltaic properties

Two D-π-A dyes based on fused acenes（carbazole, cyclopenta[2,1-b：3,4-b＇]dithiophene（CPDT） and dithieno[3,2-b：2＇,3＇-d]pyrrole（DTP）） were synthesized, characterized using UV-vis absorption spectroscopy and electrochemistry, density function theory（DFT） calculations, and used as sensitizers in dyesensitized solar cells（DSSCs）. The two sensitizers were compared thoroughly over physicochemical properties and DSSC performance. Although the DTP dye has slightly blue-shifted and weaker incident photon-to-collected electron（IPCE） conversion efficiency responses, the much increased open-circuit photovoltage values and improved charge-transfer kinetics relative to the CPDT systems result in superior power conversion efficiencies. This work reveals the potential of DTP as a bridge in the design of sensitizers.