[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][CH:11]([C:14](=O)[CH2:15][C:16](=O)[CH2:17][C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].[CH3:26][NH:27][NH2:28]>CO>[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][CH:11]([C:14]2[N:27]([CH3:26])[N:28]=[C:16]([CH2:17][C:18]3[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=3)[CH:15]=2)[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2]4-(3-Oxo-4-phenyl-butyryl)-piperidine-1-carboxylic acid tert-butyl ester (0.118 g) was dissolved in MeOH (4 mL) and added to a refluxing solution of methyl hydrazine (0.019 g) in methanol (2 mL). After 45 minutes at reflux the reaction mixture was cooled to room temperature and solvents evaporated under reduced pressure to give the crude product as a clear oil which was purified by column chromatography on silica using Et2O as eluent to give 4-(5-benzyl-2-methyl-2H-pyrazol-3-yl)-piperidine-1-carboxylic acid tert-butyl ester (0.032 g) as a clear oil; NMR (CDCl3): 1.46 (s, 9H), 1.46-1.54 (m, 2H), 1.82 (br d, 2H), 2.64 (tt, 1H), 2.78 (br t, 2H), 3.77 (s, 3H), 3.90 (s, 2H), 4.18 (br d, 2H), 5.72 (s, 1H), 7.16-7.29 (m, 5H); MS: 356 (MH+).
Wird geladen…