- Beneficial effect of cesium salts on Pd-catalyzed hydroxycarbonylation
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A Pd(0)-catalyzed hydroxycarbonylation of the aryl bromide was effectively carried out in the presence of some Cs salts such as cesium carbonate, cesium bicarbonate, and cesium acetate in wet DMF solution. For the understanding of their function, an oxy-coordinated intermediate arising from a Cs-oxygen-Pd interaction has been postulated, which is likely to be responsible for related Cs assisted catalytic processes. (C) 2000 Elsevier Science Ltd.
- Torisawa, Yasuhiro,Nishi, Takao,Minamikawa, Jun-ichi
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- A [...] intermediate 2 - methyl - 4 - N - (2 - methyl benzoyl) benzoic acid
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The invention relates to a [...] intermediate 2 - methyl - 4 - N - (2 - methyl benzoyl) benzoic acid for the preparation of the new method, the method to 3 - methylaniline as the starting material, acetate acylation, cyano, cyano hydrolysis, the amidation reaction to obtain the intermediate 2 - methyl - 4 - N - (2 - methyl benzoyl) benzoic acid. The material of the invention is easy to obtain, mild reaction conditions, high yield, does not need special equipment, without the use of highly toxic or an expensive reagent, low cost, convenient to industrial production.
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- Characterization of the stress degradation products of tolvaptan by UPLC-Q-TOF-MS/MS
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Tolvaptan (TVT) is a selective, competitive vasopressin receptor 2 antagonist used to treat hyponatremia. TVT was subjected to forced degradation under hydrolysis, oxidation, dry heat and photolysis conditions, in accordance with the ICH guideline Q1A (R2). The degradation products (DPs) formed have been characterized through UPLC-PDA and UPLC-Q-TOF-MS/MS studies. The chromatographic separation was achieved on an Acquity UPLC HSS T3 column (100 × 2.1 mm, 1.7 μm) with a mobile phase containing a gradient mixture of solvents A (0.1% formic acid) and B (acetonitrile) at a flow rate of 0.3 ml min-1 at 30 °C. The detection wavelength was set at 266 nm. The drug degraded under acid hydrolysis, base hydrolysis and oxidative conditions to form a total of 7 DPs. When methanol was used as the co-solvent during stress degradation, four additional DPs were formed which were absent when acetonitrile was used as the co-solvent. Comparison of the fragmentation pattern of the DPs with that of the drug helped in the elucidation of the structures of all the degradation products. The degradation pathway of the drug was established, which was duly justified by the mechanistic explanation. The developed UPLC method was validated as per ICH guidelines.
- Patel, Prinesh N.,Rajesh Kumar,Gananadhamu,Srinivas
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p. 21142 - 21152
(2015/03/30)
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- PROCESS FOR PREPARING BENZAZEPINE COMPOUNDS OR SALTS THEREOF
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This invention provides a process for preparing benzazepine compounds of the formula (1): wherein X1is a halogen atom, R1and R2are a lower alkyl group, or salts thereof as well as intermediate benzoic acid compounds in high yield and high purity on industrial scale, which are useful as an intermediate for preparing a pharmaceutically active 2,3,4,5-tetrahydro-1H-1-benzazepine compound having vasopressin antagonistic activity.
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Page/Page column 38-39
(2008/06/13)
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- Aminocarbonylation route to tolvaptan
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Pd-catalyzed aminocarbonylation between aryl bromide and NH-benzazepinone was effectively carried out to furnish the key intermediate for tolvaptan (up to 85%) in one step.
- Torisawa, Yasuhiro,Furuta, Takuya,Nishi, Takao,Aki, Shinji,Minamikawa, Jun-ichi
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p. 6455 - 6458
(2008/03/14)
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