Reference of 25940-35-6, Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps,and cheap raw materials. 25940-35-6, name is Pyrazolo[1,5-a]pyrimidine-3-carboxylic acid. A new synthetic method of this compound is introduced below.
To a solution of 5-[6-(difluoromethoxy)-3,4-dihydro-2H-l-benzopyran-7-yl]-l-[[2- (trimethylsilyl)ethoxy]methyl]-lH-pyrazol-4-amine (154 mg, 0.374 mmol) in DMA (3.0 mL) was added pyrazolo[l,5-a]pyrimidine-3-carboxylic acid (92.0 mg, 0.564 mmol), 4-DMAP (5.00 mg, 0.0409 mmol), DIPEA (145 mg, 1.12 mmol) and PyAOP (293 mg, 0.562 mmol). The reaction mixture was stirred at 45 C for 18 h. The reaction mixture was allowed to cool to RT and partitioned between ethyl acetate and water. The organic phase was washed with water and brine, dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was purified by silica gel chromatography eluting with ethyl acetate/petroleum ether (1/1) to afford N-[5-[6-(difiuoromethoxy)-3,4-dihydro-2H-l-benzopyran-7-yl]-l-[[2- (1224) (trimethylsilyl)ethoxy]methyl]- lH-pyrazol-4-yl]pyrazolo[ 1 ,5-a]pyrimidine-3-carboxamide (170 mg, 82%) as an off-white solid. LC/MS (Method F, ESI): [M+H]+ = 557, RT = 1.26 min.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,25940-35-6, its application will become more common.
Reference:
Patent; F. HOFFMANN-LA ROCHE AG; GENENTECH, INC.; ROMERO, F. Anthony; ZAK, Mark; ZHAO, Guiling; GIBBONS, Paul; LI, Wei; CHENG, Yun-Xing; YUEN, Po-Wai; CHENG, Limin; (275 pag.)WO2018/122212; (2018); A1;,
Pyrimidine | C4H4N2 – PubChem,
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