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1.
A series of N-substituted 2-[(2-imidazolylsulfinyl)methyl]anilines (3) was synthesized and evaluated for its biological activity against gastric H+/K(+)-ATPase prepared from rabbit stomach and gastric acid secretions in Heidenhain pouch dogs. Monoalkyl substituents on the nitrogen atom of the aniline moiety markedly inhibited the enzyme activity to the same degree as omeprazole, a representative H+/K(+)-ATPase inhibitor. Most of these compounds, administered at 3 mg/kg i.v. inhibited histamine-stimulated gastric acid secretion. The inhibitory activity of these derivatives on the enzymes at pH 6.0 was more potent than that at pH 7.4, and was distinctly correlated to stability in aqueous solution at pH 5.0.  相似文献   
2.
High-average-power and high-energy lasers with good beam quality are fundamental tools for pumping high-peak and high-average-power ultrafast Ti:sapphire laser systems. Laser-diode (LD) pumped solid slate lasers with phase conjugation offer a unique combination of efficiency, reliability, and compactness. We present the design details and performance characteristics of a 360-W 1-kHz LD pumped Nd:YAG phase-conjugated laser. We also discuss the basic design aspects and present our preliminary experimental investigations on ultrashort-pulse laser systems.  相似文献   
3.
We developed a compact equipment working at 94 GHz to replace the commonly used network analyzer for nondestructive testing of materials. The compact equipment was designed to measure the variations in the amplitude and phase of the reflected signal from the material relative to a reference signal. A good accuracy of the amplitude and phase measurement of the equipment was obtained in the confirmative experiments. The distribution of a drop of water in a wood plate is clearly visible in the millimeter wave images obtained by the amplitude and phase measurement.  相似文献   
4.
The aqueous solution of mixture of sodium decyl sulfate (SDeS) and decyltrimethylammonium bromide (DeTAB) has been found to form equilibrium multilamellar vesicles (MLV) spontaneously. We measured the surface tension of the aqueous solution of 1:1 mixture of SDeS and DeTAB as a function of temperature T at various molalities m under atmospheric pressure. The surface density, the entropy of adsorption and the entropy of vesicle formation are evaluated and compared with those of the decyltrimethylammonium decyl sulfate (DeTADeS) aqueous solution system to investigate the role of small counterions in the mechanism of equilibrium vesicle formation. The saturated surface density Gamma (H,C ) vs T curve of the SDeS/DeTAB system sits below that of the DeTADeS system. Therefore, sodium and bromide ions are negatively adsorbed and nevertheless, they neutralize the electric charge of the decyl sulfate ion DeS(-) and the decyltrimethylammonium ion DeTA(+) to some extent to weaken the electrostatic attraction between the polar head groups in the adsorbed film. The net surfactant concentration required for vesicle formation was larger in the SDeS/DeTAB system. Hence, the electrostatic attraction between the polar head groups of the surfactant ions which is one of the major driving forces for vesicle formation is weakened by the presence of the counterions Na(+) and Br(-). Small but distinct changes in the surface density and the entropies of MLV formation of the SDeS/DeTAB system from those of the DeTADeS system were also found.  相似文献   
5.
1,4-Bis(dimethylsilyl)benzene reacted with [Pt3H(PEt3)3(μ-PPh2)3] at room temperature to yield trinuclear Pt complex [Pt3(SiMe2C6H4SiMe2H)(PEt3)2(μ-PPh2)3] (1a). Heating a solution containing an equimolar mixture of [Pt3H(PEt3)3(μ-PPh2)3] and 1a at 60 °C produced a hexanuclear Pt complex [(PEt3)2(μ-PPh2)3Pt3(SiMe2C6H4SiMe2)Pt3(PEt3)2(μ-PPh2)3] (2a). Complex 1a was characterized by X-ray crystallography and NMR spectroscopy, while the structure of 2a was determined by X-ray crystallography of single crystals containing 2a and [Pt3H2(PEt3)2(μ-PPh2)4] in 1:1 ratio. [Pt3(SiMe2fcSiMe2H)(PEt3)2(μ-PPh2)3] (fc = Fe(η5-C5H4)2) (1b) and [(PEt3)2(μ-PPh2)3Pt3(SiMe2fcSiMe2)Pt3(PEt3)2(μ-PPh2)3] (2b) were obtained similarly from the reactions of 1,1′-bis(dimethylsilyl)ferrocene with [Pt3H(PEt3)3(μ-PPh2)3] and characterized by NMR spectroscopy and elemental analyses.  相似文献   
6.
[reaction: see text] The Peterson reaction between (t-BuO)Ph(2)SiCH(2)CN and various aldehydes furnishes the corresponding beta-monosubstituted alpha,beta-unsaturated cyanides with high Z selectivity (Z:E = 92:8 to >98:2).  相似文献   
7.
8.
Diazepinoquinoxalines 3, 4 and imidazolobenzopteridines 5, 6a-d, 7a-d, 8, 9 were synthesized from 3-allylamino-6,7-dimethyl-2-quinoxalinecarboxamide ( 1 ) and 2-allylamino-6,7-dimethyl-3,4-dihydrobenzo[g]pteridin-4-one ( 2 ) by the intramolecular cyclization using phenylselenenyl chloride.  相似文献   
9.
Meso and racemic isomers of 1,1′-bis(α-hydroxyalkyl)ferrocene derivatives, and trans and cis isomers of 7-oxa[3]ferrocenophanes have been isolated. The configurations of these isomers have been determined both by spectroscopy and from their reaction behavior. It has been found that the ring-closure and ring-opening interconversion reactions between 1,1′-bis(α-hydroxyalkyl)ferrocenes and 7-oxa[3]ferrocenophanes are stereospecific. PMR spectra of the diols and ethers have been examined at 100 MHz in CF3COOH, and the existence of α-[1′-(α-hydroxyalkyl)ferrocenyl]carbonium ions has been demonstrated in this acid. A mechanism for the various interconversion reactions is proposed on the basis of their stereospecific reactivity and from the PMR spectra of the carbonium ions.  相似文献   
10.
The main object of this paper is the module A of regular differential forms on a. finitely generated algebra or a local analytic algebra A over a field k, which was defined in [9].A is a finitely generated module over the De Rham-algebra A with an exterior differentiation d. In the reduced, pure dimensional, characteristic zero case A can be described as a submodule of the module Q(A)AA of meromorphic differential forms, and it has the image of A as submodule. Now in this case one can compare the De Rnam-cohomology of A with the cohomology of A, which is of interest in studying analytic or algebraic singularities.  相似文献   
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