With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.115761-79-0,1-(2,4-Difluorophenyl)piperazine,as a common compound, the synthetic route is as follows.
A mixture of 2- (5-amino-2- (furan-2-yl) -7H-pyrazolo [4, 3-e] [1, 2, 4] triazolo [1, 5-c] pyrimidin-7-yl) -4-methylpentanoic acid (35.5 0.1 mmol) , 1- (2, 4-difluorophenyl) piperazine (19.8 mg, 0.1 mmol) , HATU (46 mg, 0.12 mmol) and DIPEA (25.8 mg, 0.2 mmol) in DMF (3 mL) was stirred overnight. The reaction mixture was poured into H2O (15 mL) and extracted with EtOAc (20 mL x 3) . The combined organic layers were washed with brine, dried over Na2SO4, concentrated and purified by column chromatography (petroleum ether/EtOAc = 10: 1 3: 1) to give the target compound (40 mg, 74.6%) .1H NMR (400 MHz, DMSO-d6) delta 8.21 (s, 1H) , 8.15 (s, 2H) , 7.95 (m, 1H) , 7.23 (d, J = 3.2 Hz, 1H) , 7.21 -7.12 (m, 1H) , 7.02 -6.91 (m, 2H) , 6.74 (m, 1H) , 5.64 (dd, J = 9.6, 4.4 Hz, 1H) , 3.74 (m, 1H) , 3.62 (m, 2H) , 3.49 (m, 1H) , 2.94 (m, 2H) , 2.75 (m, 1H) , 2.39 (m, 1H) , 2.31 -2.19 (m, 1H) , 1.91 -1.80 (m, 1H) , 1.27 (mz, 1H) , 0.95 (d, J = 6.4Hz, 3H) , 0.83 (d, J = 6.4Hz, 3H) ppm. MS: M/e 536 (M+1)+.
115761-79-0, As the paragraph descriping shows that 115761-79-0 is playing an increasingly important role.
Reference：
Patent; BEIGENE, LTD.; ZHANG, Guoliang; SUN, Hanzi; ZHOU, Changyou; (253 pag.)WO2020/20097; (2020); A1;,
Piperazine – Wikipedia
Piperazines – an overview | ScienceDirect Topics