With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.21043-40-3,1-Cyclopentylpiperazine,as a common compound, the synthetic route is as follows.
Step 1: 6-(4-Cyclopentyl-piperazin-1-yl)-1H-pyrrolo[2,3-b]pyridine-2-carboxylic acid ethyl ester A mixture of 1 g (3.7 mmol) 6-bromo-1H-pyrrolo[2,3-b]pyridine-2-carboxylic acid ethyl ester (prepared according to the method described in WO 2003/064423 A1) and 2.8 g (18.6 mmol) 1-cyclopentyl-piperazine (commercially available) was heated to 140 C. for 1 h. The mixture was absorbed on isolute and purified by flash column chromatography on silica eluting with a gradient formed from n-heptane and ethyl acetate (0.1% NEt3). Evaporation of the product fractions yielded 501 mg (39%) of the title compound as white solid. MS: (m/e): 343.4 (MH+)., 21043-40-3
As the paragraph descriping shows that 21043-40-3 is playing an increasingly important role.
Reference：
Patent; Nettekoven, Matthias; Roche, Olivier; US2007/142358; (2007); A1;,
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