1373038-56-2Relevant articles and documents
Synthesis method of parecoxib sodium isomeric impurities
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, (2019/01/23)
The invention provides a synthesis method of parecoxib sodium isomeric impurities. Structures of the parecoxib sodium isomeric impurities are shown in formulae I and II in the description. The synthesis method comprises the following steps: the compound as shown in the formula I is subjected to reaction with the compound as shown in formula II or the compound as shown in formula III under the action of alkali, and a compound as shown in formula IV is generated; the corresponding parecoxib sodium isomeric impurities are generated by reduction reaction, diazotization, sulfonylation, amino substitution reaction and acylation reaction; the total reaction yield is higher than 22%, and purity of a target product is higher than 99%.
Preparation method of parecoxib sodium impurity
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, (2018/11/03)
The invention discloses a preparation method of parecoxib sodium impurity 3-[(4- phenyl)-5-methyl-3-isoxazole] benzene sulfonamide. The parecoxib sodium impurity is formed by performing cyclizing, sulfonation, ammonolysis, bromination and coupling on 1-phenyl-1, 2-propanedione serving as a raw material. 1H-NMR, 13C-NMR, DEPT, gCOSY, HMQC and HMBC maps confirm that the structure of the parecoxib sodium impurity, the preparation method is novel, the parecoxib sodium impurity is detected, and the purity of related substance is greater than or equal to 98 percent.
Application of [3+2]-cycloaddition in the synthesis of valdecoxib
Reddy, Anumula Raghupathi,Goverdhan, Gilla,Sampath, Aalla,Mukkanti, Khagga,Reddy, Padi Pratap,Bandichhor, Rakeshwar
, p. 639 - 649 (2012/01/13)
A large scale synthesis of valdecoxib 1 is described. Our work features potential application of [3+2]-dipolar cycloaddition involving enamine and in situ-generated nitrile oxide derivatives. Dr. Reddy's Laboratories Ltd.