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11.
Matsuhisa A Taniguchi N Koshio H Yatsu T Tanaka A 《Chemical & pharmaceutical bulletin》2000,48(1):21-31
Arginine vasopressin (AVP) has a dual action mainly in the periphery, i.e., vasoconstriction and water reabsorption via V1A and V2 receptors; it may play a role in a number of diseases, including congestive heart failure (CHF), hypertension, renal disease, edema, and hyponatremia. We have attempted to develop a new series of orally active AVP antagonists for both V1A and V2 receptors based on the hypothesis that the blockade of both V1A and V2 receptors might be beneficial to CHF patients. In this report, a series of compounds structurally related to 4'-(1,4,5,6-tetrahydroimidazo[4,5-d][1]benzoazepine-6- carbonyl)benzanilide and 4'-(5,6-dihydro-4H- thiazolo[5,4-d][1]benzoazepine-6-carbonyl)benzanilide were synthesized and examined for AVP antagonist activity for both V1A and V2 receptors. As a result, it was found that the 4'-(1,4,5,6-tetrahydroimidazo[4,5-d][1]benzoazepine-6-carbon yl)-2- phenylbenzanilide derivatives showed potent binding affinity for both V1A and V2 receptors. Especially, 4'-(2-methyl-1,4,5,6- tetrahydroimidazo[4,5-d][1]benzoazepine-6-carbonyl)-2-phe nylbenzanilide monohydrochloride (18, YM087 = conivaptan hydrochloride) exhibited potent binding affinity and AVP antagonist activity, after intravenous administration, for both V1A and V2 receptors. Furthermore, YM087 exhibited the most potent oral activity for the V2 receptor. Details of the synthesis and pharmacological properties of this series are presented. 相似文献
12.
A mass spectrometric study of about 30 triazine derivatives from amino acids and peptides is reported. These derivatives incorporated the C-terminal of amino acids and peptides in the ring. In contrast to the mass spectra of amino acids and peptide esters reported previously, they always showed characteristic fragments, denoting the presence of the terminal triazine ring. By using this peak as a marker, it is easy to estimate the C-terminal of peptides. In dipeptides, the N-terminal and C-terminal are determined simultaneously. 相似文献
13.
H Aibata K Torizumi T Okada S Kiji R Yamada K Shimada K Taniguchi Y Aoki 《Radioisotopes》1987,36(11):594-596
In order to evaluate the gastric emptying and postprandial mixing of bile with food, the scintigraphies of hepatobiliary and gastrointestinal tracts by using three different kinds of radioisotopes were performed simultaneously (99mTc-E.HIDA for hepatobiliary scintigraphy, 111In-DTPA containing orange juice and 131I-albumin containing scrambled egg for gastrointestinal scintigraphy). This method was available for observation of gastric emptying of liquid and solid foods and also examination of the mixing effect of bile and food quantitatively. 相似文献
14.
A variety of diaryl acetylenes were obtained in good yields when lithium hexamethyldisilazide was added to a solution of arylmethyl sulfone, aryl aldehyde, and chlorodiethylphosphate in THF. In this one‐shot process, a number of transformations such as aldol reaction, phosphorylation of aldolate, and double elimination of the resulting β‐substituted sulfone proceeded successively to afford the desired acetylenes. The one‐shot process was accelerated by the substitution of halogen atoms on the phenyl groups, and unsymmetrically substituted diaryl acetylenes were obtained without contamination of the dehalogenated products. Diaryl acetylenes with other substituents such as CF3, ethoxycarbonyl, dimethylamino, TMS‐acetylene groups, as well as pyridinyl and thienyl moieties were also accessible with this method. However, methoxy‐substituted compounds were obtained in moderate yields under the same conditions, but the yields were increased when lithium diisopropylamide was used instead. 相似文献
15.
T. Yamamoto A. Taniguchi S. Dev E. Kubota K. Osakada K. Kubota 《Colloid and polymer science》1991,269(10):969-971
Organosols of NiS, PdS, and MnS in N,N-dimethylformamide were prepared by reaction of the metal acetate with H2S. Organosols of mixed-metal sulfides (Zn
x
Cd1–x
S, Hg
x
Cd1–x
S, Hg
x
Cu1–x
S, Cd
x
Mn1–x
S, Hg
x
Mn1–x
S, Hg
x
Cd1–x
S, and Mn
x
Zn1–x
S) were similarly obtained by reaction of mixtures of the metal salts with H2S. The organosol of Zn0.5Cd0.5S contained particle with two particle size distributions centered at 6.5 nm and 29 nm, as revealed by Ar laser-scattering analysis. The metal sulfides are recovered by addition of Et2O to the organosols. Zn
x
Cd1–x
S thus obtained shows magnetic susceptibility in the range 0.5×10–6–2.3×10–6 emug–1 depending on thex value. Addition of polymers to the organosols affords semiconducting films of metal sulfide-polymer composites. 相似文献
16.
Three-component reactions of aldehydes, ammonia, and allylboronates were found to provide homoallylic primary amines in high yields with high chemo- and stereoselectivities. A two-step, one-pot, stereoselective synthesis of an uncommon alpha-amino acid, alloisoleucine, was achieved utilizing this reaction. 相似文献
17.
[reaction: see text]. An In(OTf)(3)-catalyzed addition of a beta-ketoester to acetylene in the presence of molecular sieves produces a alpha-vinylated ketoester in good to excellent yield. The vinylation reaction proceeds without any loss of elements in starting molecules under solvent-free conditions and allows the use of welding-grade acetylene, providing a practical method for synthetic utilization of acetylene gas. 相似文献
18.
Pavel Smirnov Hisanobu Wakita Masaharu Nomura Toshio Yamaguchi 《Journal of solution chemistry》2004,33(6-7):903-922
The structure and complex formation of concentrated aqueous gallium(III) bromide (GaBr3) solutions have been investigated over a temperature range 80–333 K by Raman spectroscopy, X-ray absorption fine structure (XAFS), and X-ray diffraction. The Raman spectra obtained at various [Br?]/[Ga3+] molar ratios and temperatures have shown that complex formation between Ga3+ and Br? occurs as a predominant species, with [GaBr4]? at [Ga3+] as high as 1~2 M (M = mol?dm ?3) and [Br?]/[Ga3+] ratios > ~2, and that cooling of the solutions favors the formation of the aqua Ga3+. The intermediate species were not seen in the Raman spectra. The XAFS data have revealed that the aqua complex has a sixfold coordination as [Ga(H2O)6]3+ with a Ga3+–H2O distance of (1.96 ± 0.02) Å, whereas the [GaBr4]? complex has a Ga3+–Br? distance of (2.33± 0.02) Å, and that vitrification of the aqueous GaBr3 solution at liquid nitrogen temperature shifts the equilibrium toward the aqua complex. The X-ray diffraction data at different subzero temperatures have shown a tendency of decreasing Ga3+–Br? and increasing Ga3+–H2O interactions with lowering temperature, confirming the preference of aqua Ga3+ in the supercooled liquid state as well as in the glassy state. The Ga3+–H2O distance of ~1.8 Å for the tetrahedral coordination was found in a 2.01 M gallium(III) bromide solution with a [Br?]/[Ga3+] ratio of 3.7 and gradually increased to a value of 1.92 Å for octahedral geometry with decreasing temperature, suggesting that equilibrium shifts from [GaBr4]? to [Ga(H2O)6]3+ through intermediate species, [GaBr n ](3?n)+ (n = 2 and 3). The Ga3+–Br? and Br?–Br? distances within [GaBr4]? with an almost tetrahedral symmetry are (2.35± 0.02) and (3.82± 0.03) Å, respectively. The Ga3+ has the second hydration shell at (4.03± 0.03) Å and the hydration of Br? is characterized with a Br?–H2O distance of (3.35± 0.02) Å at all temperatures investigated. 相似文献
19.
Ramesh P Okazaki T Taniguchi R Kimura J Sugai T Sato K Ozeki Y Shinohara H 《The journal of physical chemistry. B》2005,109(3):1141-1147
Double-wall carbon nanotubes (DWNTs) have been selectively synthesized over Fe/Co loaded mesoporous silica by catalytic chemical vapor deposition of alcohol. Several silica materials with desired pore diameter and morphology have been investigated for the DWNT growth. The diameter distribution and selectivity of the DWNT are found to depend on the reaction temperature, pore size, and thermal stability of the support material. A high-yield synthesis of DWNTs has been achieved at 900 degrees C over high-temperature stable mesoporous silica. The outer diameter of DWNTs is found to be in the range of 1.5-5.4 nm with a "d" spacing of 0.38 +/- 0.02 nm between inner and outer layers, which is much larger than those of multiwall carbon nanotubes. 相似文献
20.
Nakayama M Tanaka A Sato Y Tonosaki T Ogura K 《Langmuir : the ACS journal of surfaces and colloids》2005,21(13):5907-5913
Manganese and molybdenum mixed oxides in a thin film form were deposited anodically on a platinum substrate by cycling the electrode potential between 0 and +1.0 V vs Ag/AgCl in aqueous manganese(II) solutions containing molybdate anion (MoO(4)2-). A possible mechanism for the film formation is as follows. First, electrooxidation of Mn2+ ions with H2O yields Mn oxide and protons. Then, the protons being accumulated near the electrode surface react with MoO(4)2- to form polyoxomolybdate through a dehydrated condensation reaction (by protonation and dehydration). The condensed product coprecipitates with the Mn oxide. Cyclic voltammetry of the Mn/Mo oxide film-coated electrode in aqueous 0.5 M Na2SO4 solution exhibited a pseudocapacitive behavior with higher capacitance and better rate capability than that of the pure Mn oxide prepared similarly, most likely as a result of an increase in electrical conductivity of the film. Electrochemical quartz crystal microbalance and X-ray photoelectron spectroscopy clearly demonstrated that the observed pseudocapacitive behavior results from reversible extraction/insertion of hydrated protons to balance the charge upon oxidation/reduction of Mn3+/Mn4+ in the film. 相似文献