cas 331943-04-5, N-De(4-sulfonaMidophenyl)-N'-(4-sulfonaMidophenyl) Celecoxib

Articles about 331943-04-5Total 6 be found

Synthesis and Spectral Characterization of Impurities of a COX-2 Selective Drug, Celecoxib
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Lee, Young Hee,Vishwanath, Manjunatha,Lanka, Srinu,Lee, Eunhwa,Park, Yongbin,Lee, Sunhwan,Sim, Jaeuk,Lee, Seohoo,Lee, Kiho,Viji, Mayavan,Lee, Heesoon,Jung, Jae-Kyung
p. 479 - 480
(2019)
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Selective, Metal-Free Approach to 3- or 5-CF3-Pyrazoles: Solvent Switchable Reaction of CF3-Ynones with Hydrazines
A detailed study of the reaction of trifluoroacetylated acetylenes and aryl (alkyl) hydrazines was performed, aimed to the regioselective synthesis of 3- or 5-trifluoromethylated pyrazoles. It was found that the regioselectivity of reaction depends dramatically on the solvent nature. Highly polar protic solvents (hexafluoroisopropanol) favor the formation of 3-trifluoromethylpyrazoles. In contrast, when the reaction was performed in polar aprotic solvents (DMSO), the formation of their 5-CF3-substituted isomers was preferentially observed. Alternatively, the regioselective assembly of 3-CF3-substituted pyrazoles can be performed via two-step one-pot procedure. The reaction of trifluoromethylated ynones with aryl (alkyl) hydrazines in the presence of acidic catalysts leads to formation of the corresponding hydrazones. The latter can be smoothly transformed into 3-CF3-pyrazoles by treatment with a base. This solvent-switchable procedure was used for the preparation of such important drugs as Celebrex and SC-560 as well as their isomers in gram scale. The possible reaction mechanism is discussed.
Muzalevskiy, Vasiliy M.,Rulev, Alexander Yu.,Romanov, Alexey R.,Kondrashov, Evgeniy V.,Ushakov, Igor A.,Chertkov, Vyacheslav A.,Nenajdenko, Valentine G.
p. 7200 - 7214
(2017/07/26)

Solvent- and transition metal catalyst-dependent regioselectivity in the [3+2]cyclocondensation of trifluoromethyl-α,β-ynones with hydrazines: Switchable access to 3- and 5-trifluoromethylpyrazoles
The regioselectivity of the [3+2]cyclocondensation of trifluoromethyl-α,β-ynones with hydrazines can be readily tuned to preferentially afford either 3- or 5-trifluoromethylpyrazoles through variation of the reaction conditions. Under catalysis with copper(II) acetate (2.0 mol%), cyclocondensation proceeded smoothly to yield 3-trifluoromethylpyrazoles with high regioselectivity. In contrast, when the reaction was conducted in dimethyl sulfoxide under catalyst-free conditions, the formation of 5-trifluoromethylpyrazoles was predominantly observed.
Hsieh, Min-Tsang,Kuo, Sheng-Chu,Lin, Hui-Chang
p. 683 - 689
(2015/03/18)

One-pot copper-catalyzed synthesis of N-functionalized pyrazoles from boronic acids
A straight-forward route to prepare a diverse set of N-aryl pyrazoles via a one-pot copper-catalyzed boronic acid coupling and cyclization protocol is presented. A variety of aryl and heteroaryl N-functionalized pyrazoles not easily accessible by other means were formed in good yield from readily available boronic acid precursors in an operationally simple procedure.
Beveridge, Ramsay E.,Fernando, Dilinie,Gerstenberger, Brian S.
scheme or table
p. 5005 - 5008
(2011/01/12)

An improved and scalable process for celecoxib: A selective cyclooxygenase-2 inhibitor
An improved, scalable and commercially viable process is developed for an active pharmaceutical ingredient, celecoxib.
Reddy, Anumula Raghupathi,Sampath, Alla,Goverdhan, Gilla,Yakambaram, Bojja,Mukkanti, Kagga,Reddy, Padi Pratap
experimental part
p. 98 - 101
(2010/04/22)

SYNTHESIS OF DIARYL PYRAZOLES
A process for the qualitative preparation of 3-haloalkyl-1H-pyrazoles suitable for efficient, high payload commercial application.
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(2010/02/04)