1034025-94-9Relevant academic research and scientific papers
A 2, 4, 5-trifluorophenylacetic acid method for the preparation of
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, (2016/10/08)
The invention discloses a preparation method 2,4,5-trifluorophenylacetic acid. The method is characterized by consisting of four reaction steps of: A, reaction of 2,4,5-trifluoronitrobenzene (I) and diethyl malonate which are condensed to prepare 2,5-difloro-4-nitrobenzophenone diethyl malonate; B, hydrolysis, acidification and decarboxylic reaction of dibasic ester; C, reduction reaction of nitryl; and D, diazotization fluoridation of amino. The four reaction steps can be sequentially carried out according to A, B, C and D, or A, C, B and D, or A, C, D and B. According to the preparation method provided by the invention, condensation of 2,4,5-trifluoronitrobenzene (I) and diethyl malonate is easy to realize by means of high substituting activity of nitryl p-fluorine, and the raw material 2,4,5-trifluoronitrobenzene (I) is low in cost and easy to obtain and can be easily prepared by nitration and fluorination of 2,4-dichlor fluorbenzene. Compared with the prior art, the preparation method provided by the invention has the characteristics of low-cost and easily obtained raw materials, mild reaction condition, high total yield, low production cost and the like, and is comparatively suitable for industrialized production.
BENZAMIDE DERIVATIVES AS EP4 RECEPTOR AGONISTS
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Page/Page column 43, (2008/12/06)
A compound of formula (I) or a pharmaceutically acceptable derivative thereof, wherein, R1, R2, R3, R4, R5, m, n and X are as defined in the specification; a process for preparing such compounds; a pharmaceutical composition comprising such compounds; and the use of such compounds in medicine.
