With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.59702-07-7,1-Methylpiperazin-2-one,as a common compound, the synthetic route is as follows.
59702-07-7, Example 16. Preparation of Compound Nos. 136. 136a and 136b To a solution of l-[4-[(3-cyclopentyl-lH-pyrazol-5-yl)amino]-6,7-dihydro-5H- cyclopenta[d]pyrimidin-2-yl]pyrrolidine-2-carboxylic acid hydrochloride (500 mg, 1.19 mmol) in DMF (6 mL) was added l-methylpiperazin-2-one (205 mg, 1.79 mmol), HOBt (16 mg, 0.11 mmol), EDC’HCl (320 mg, 1.67 mmol), and DIPEA (618 mg, 4.79 mmol), and the reaction mixture was stirred at RT for 18 h. The reaction mixture was diluted with water (50 mL) and extracted with EtOAc (2×50 mL). The combined organic layers were washed with water (8×50 mL) and dried over anhydrous sodium sulfate. Removal of solvent under reduced pressure gave a crude product that was purified by reverse phase HPLC followed by chiral HPLC to afford 20 mg of 4-[(2S)-l-[4-[(3-cyclopentyl-lH-pyrazol-5-yl)amino]-6,7- dihydro-5H-cyclopenta[d]pyrirmdin-2-yl]pyrrolidine-2-carbonyl]-l-methyl-piperazin-2-one (Compound No. 136b). 1H NMR (CD3OD, 400 MHz) 1.60-1.90 (m, 8H), 1.92-2.20 (m, 8H), 2.30-2.42 (m, 1H), 2.60-2.80 (m, 6H), 2.97-3.12 (m, 1H), 3.22-3.56 (m, 3.61-4.30 (m, 4H), 5.02 (brs, 1H), 5.75 (brs, 1H).
As the paragraph descriping shows that 59702-07-7 is playing an increasingly important role.
Reference：
Patent; MEDIVATION TECHNOLOGIES, INC.; CHAKRAVARTY, Sarvajit; RAI, Roopa; GREEN, Michael, John; ANSARI, Amantullah; AGARWAL, Anil, Kumar; (216 pag.)WO2016/3827; (2016); A2;,
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