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81.
The metabolites of trimeprazine were identified in urine of rats by gas chromatography-mass spectrometry. After the oral administration of trimeprazine, the urinary metabolites were extracted with diethyl ether before or after hydrolysis with beta-glucuronidase. The identified metabolites were N-demethyltrimeprazine,3-hydroxytrimeprazine,N-demethyl-3-++ +hydroxytrimeprazine and trimeprazine sulphoxide. 相似文献
82.
Mechanism of sorption of phenols from aqueous solutions onto surfactant-modified montmorillonite 总被引:6,自引:0,他引:6
Equilibrium and kinetic studies on the sorption of phenol, m-nitrophenol (m-NP), and o-cresol from water onto montmorillonite modified with cetyltrimethylammounium bromide (CTAB) were conducted. Experiments were carried out as a function of solution pH, sorbate concentration, and temperature (25-55 degrees C). It was shown that the sorption capacity decreased in the order phenol>o-cresol>m-NP. The Langmuir, dual-mode sorption, and Redlich-Peterson models were tested to fit the sorption isotherms of single-solute systems, whereas the Langmuir competitive model was used to describe bisolute sorption equilibria. Thermodynamic parameters (DeltaH degrees and DeltaS degrees ) and the mean free energy (E) for the sorption of phenols were determined from the temperature dependence of the distribution constant and the Dubinin-Radushkevick equation, respectively. A simplified kinetic model was proposed to confirm the sorption mechanism. 相似文献
83.
Yoshikatsu Ito Meng Ji-Ben Shin Suzuki Yoshitaka Kusunaga Teruo Matsuura Keiichi Fukuyama 《Tetrahedron letters》1985,26(17):2093-2096
In contrast to simple imidazoles, 1-methy1–2,4,5-triphenylimidazole () produced stable oxetane photoadducts - with good efficiency upon irradiation in the presence of benzophenone derivatives - in acetonitrile solution. Irradiation in the solid-phase was also studied. The oxetanes - readily underwent cycloreversion by acid catalysis or by heating. 相似文献
84.
85.
Tae?Shin?Chung Young?Mee?Na Shin?Won?Kang Ok-Sang?JungEmail author Young-A?Lee 《Transition Metal Chemistry》2005,30(5):541-545
Hydrogen peroxide oxidation of platinum(II) compounds containing labile groups such as Cl, OH, and alkene moieties has been carried out and the products characterized. The reactions of [PtII (X)2 (N–N)] (X = Cl, OH, X2 = isopropylidenemalorate (ipm); N–N 2,2-dimethyl-1,3-propanediamine [(dmpda), N-isopropyl-1,3-propanediamine (ippda)] with hydrogen peroxide in an appropriate solvent at room temperature affords [PtIV (OH)(Y)(X)2(N–N)] (Y = OH, OCH3). The crystal structures of [PtIV(OH)(OCH3)(Cl)2(dmpda)]·2H2O (P-1 bar, a = 6.339(2) Å , b = 9.861(1) Å, c = 11.561(1) Å, a = 92.078(9)°, β = 104.78(1)°, γ=100.54(1)°, V = 684.3(2) Å3, Z = 2R = 0.0503) and [PtIV(OH)2(ipm)(ippda)]·3H2O (C 2/c, a = 27.275(6) Å, b=6.954(2) Å, c = 22.331(4) Å, β = 118.30(2)°, V = 3729(2) Å3, Z = 8, R = 0.0345) have been solved and refined. The local geometry around the platinum(IV) atom approximates to a typical octahedral arrangement with two added groups (OH and OCH3; OH and OH) in a transposition. The platinum(IV) compounds with potential labile moieties may be important intermediate species for further reactions. 相似文献
86.
Moonhor Ree Jong-Seong KimJae Jung Kim Byeang Hyean KimJuyoung Yoon Heesoo Kim 《Tetrahedron letters》2003,44(45):8211-8215
The synthesis of novel cavitands containing four fluorophores [tert-butoxycarbonyl protected 2,2′-bis(furyl)benzidine (t-BOC FurylBz) or 5,5′-bis(4-aminophenyl)-2,2′-bifuryl (t-BOC PFDA)] and ionophoric functional groups on the upper rim is reported. The cavitands bearing the four fluorophores emit blue light photoluminescence. In particular, the cavitand containing PFDA moieties exhibits a high photoluminescence quantum yield. 相似文献
87.
Binyuan Liu Yang Li Boo-gyo Shin Li Zhang Weidong Yan 《Polymer Degradation and Stability》2007,92(5):868-875
The thermal properties and degradation behaviors of poly(norbornene-2,3-dicarboxylic acid dialkyl esters) (PNB-dialkyl esters) (alkyl = Me (PNB-Me), Et (PNB-Et), Pr (PNB-Pr), and Bu (PNB-Bu)) were investigated by thermogravimetric analysis (TGA) in dynamic conditions and by infrared (IR) spectroscopy. The PNB-dialkyl esters show good thermal stability up to 350 °C, and the thermal stability decreases in the order Me > Et > Pr > Bu with the increase in size of side chain. The effect of side-chain size on the thermal degradation behaviors of PNB-dialkyl esters is evidenced by one-step thermal degradation profile for PNB-Me while two-step thermal degradation profile for PNB-Et, PNB-Pr, and PNB-Bu. Transformation is deduced to undergo β-hydrogen elimination and formation of anhydride group in the first stage of thermal degradation reaction according to TGA and IR results for PNB-Et, PNB-Pr, and PNB-Bu. The apparent activation energy and thermal degradation model of PNB-dialkyl esters are estimated by means of Ozawa-Flynn-wall method and Phadnis-Deshpande method, respectively. 相似文献
88.
Jin R Jureller JE Kim HY Scherer NF 《Journal of the American Chemical Society》2005,127(36):12482-12483
Femtosecond laser excited second harmonic (SH) activity from single Ag nanoparticles is reported. A correlation of SH single-particle measurements with high-resolution imaging of particle morphology by TEM was achieved by creating position markers on an optical and electron transparent substrate (Si3N4 thin film, approximately 100 nm). We compared the SH activity of single Ag nanoparticles (nanospheres versus nanorods) and cluster structures (composed of two or multiple particles, e.g., dimers and trimers). The direct correlation of single-particle structures and SH activity, spectral and power dependence, strongly suggests one-photon resonant driven nonlinear oscillator response mechanism. 相似文献
89.
Somatostatin (SST) is a well-known neuropeptide that is expressed throughout the brain. In the cortex, SST is expressed in a subset of GABAergic neurons and is known as a protein marker of inhibitory interneurons. Recent studies have identified the key functions of SST in modulating cortical circuits in the brain and cognitive function. Furthermore, reduced expression of SST is a hallmark of various neurological disorders, including Alzheimer’s disease and depression. In this review, we summarize the current knowledge on SST expression and function in the brain. In particular, we describe the physiological roles of SST-positive interneurons in the cortex. We further describe the causal relationship between pathophysiological changes in SST function and various neurological disorders, such as Alzheimer’s disease. Finally, we discuss potential treatments and possibility of novel drug developments for neurological disorders based on the current knowledge on the function of SST and SST analogs in the brain derived from experimental and clinical studies.Subject terms: Molecular neuroscience, Drug development 相似文献
90.
Chan Sik Cho Tae Kyung Kim Tae‐Jeong Kim Sang Chul Shim Nam Sik Yoon 《Journal of heterocyclic chemistry》2002,39(2):291-294
Nitroarenes are reductively cyclized with 3‐amino‐1‐propanols in dioxane/H2O in the presence of a ruthenium catalyst and tin(II) chloride dihydrate together with isopropanol to afford the corresponding quinolines. A reaction pathway involving initial reduction of nitroarenes to anilines, propanol group transfer from 3‐amino‐1‐propanols to anilines, N‐alkylation of anilines by 3‐anilino‐1‐propanols and heteroannulation of 1,3‐dianilinopropanes is proposed. 相似文献