38353-06-9Relevant articles and documents
Rates and equilibrium constants for the covalent hydration of 5-bromo-2(1H)-pyrimidinone in aqueous solution
Tee, Oswald S.,Pika, Jana,Kornblatt, Judith M.,Trani, Michael
, p. 1267 - 1272 (1986)
The kinetics of bromination of the title compound (1) have been measured in aqueous solutions of pH 0-6.The change in the order of reaction which occurs around pH 2.5 is explained by 1 reacting via its covalent hydrate, 3.Furthermore, there is sufficient 3 present at equilibrium that the kinetics of its equilibration with 1 were also measured.From these two studies the extent of covalent hydration of 1 is estimated to be 5percent.Kinetic studies of the bromination of the dimethyl cation 5 and of its equilibration with the pseudobase 6 were also carried out for the purposes of comparison.The present results for 1, 3, 5 and 6 are compared to earlier results for 2-pyrimidinone and analogous derivatives.
Characterization of degradation products of macitentan under various stress conditions using liquid chromatography/mass spectrometry
Yerra, Naga Veera,Pallerla, Pavankumar,Pandeti, Sukanya,Tabet, Jean-Claude,Thota, Jagadeshwar Reddy
, p. 1075 - 1084 (2018/06/11)
Rationale: Stress testing of a drug candidate is an important step in the drug discovery and development process. The presence of degradation products in a drug affects the quality as well as the safety and efficacy of drug formulation. Hence, it is essential to develop an efficient analytical method which could be useful for the separation, identification and characterization of all possible degradation products (DPs) of a drug. Macitentan (MT) is an endothelin receptor antagonist (ERA) drug used to treat high blood pressure in the lungs. Comprehensive stress testing of MT was carried out as per ICH guidelines to understand the degradation profile of the drug. Methods: MT was subjected to various stress conditions such as acidic, basic, neutral hydrolysis, oxidation, photolysis and thermal conditions; and the resulting degradation products were investigated using liquid chromatography/diode-array detection/electrospray ionization high-resolution mass spectrometry (LC/DAD/ESI-HRMS) and tandem mass spectrometry (MS/MS) techniques. An efficient and simple ultra-high-performance liquid chromatography (UHPLC) method has been developed using an Accucore C18 column (4.6?×?150?mm, 2.6?μm) using a gradient elution of 5?mM ammonium formate and acetonitrile as mobile phases. Results: MT was found to degrade under acid and base hydrolysis stress conditions; whereas it was stable under oxidation, neutral hydrolysis, thermal and photolytic conditions. MT formed nine DPs (DP1 to DP9) and one DP (DP10) under acidic and basic hydrolytic conditions, respectively. All the degradation products (DP1 to DP10) were identified and characterized by LC/MS/MS in positive ion mode with accurate mass measurements. Conclusions: MT was found to be labile under hydrolytic conditions. The structures of the DPs were characterized by appropriate mechanisms. The proposed method can be effectively used for the characterization of MT and its DPs.
FACTOR IXA INHIBITORS
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Page/Page column 142, (2015/11/09)
In its many embodiments, the present invention provides a novel class of benzamide compounds represented by Formula (I) or pharmaceutically acceptable salts or solvates thereof, or pharmaceutical compositions comprising one or more said compounds or pharmaceutically acceptable salts or solvates thereof, and methods for using said compounds or pharmaceutically acceptable salts or solvates thereof for treating or preventing a thromboses, embolisms, hypercoagulability or fibrotic changes.