C([O:3][C:4]([C:6]1[CH:7]=[N:8][C:9]2[N:10]([N:12]=[C:13]([NH2:21])[C:14]=2[C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][N:16]=2)[CH:11]=1)=[O:5])C.[OH-].[K+].[ClH:24].CCOCC>C(O)C>[ClH:24].[NH2:21][C:13]1[C:14]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][N:16]=2)=[C:9]2[N:8]=[CH:7][C:6]([C:4]([OH:5])=[O:3])=[CH:11][N:10]2[N:12]=1A solution of 2-amino-3-pyridin-2-yl-pyrazolo[1,5-a]pyrimidine-6-carboxylic acid ethyl ester (1.58 g, 5.58 mmol) and potassium hydroxide (0.95 g, 16.7 mmol) in ethanol (30 mL) was refluxed for 3 h, then cooled down to room temperature. The precipitate was filtered off, washed with ether, suspended in ether, treated with 2M HCl/Et2O (15 mL, 30 mmol), stirred 0.5 h, and filtered, washing with ether to provide an HCl salt of the title compound as a brown solid (0.88 g, 54% yield). MS (ES+) 256. δH (500 Mhz, DMSO-d6) 7.25 (1H, m), 7.94 (1H, t), 8.56 (1H, d), 8.60 (1H, d), 8.83 (1H, d), 9.16 (1H, d).
Wird geladen…
