O=C1C2C(=CC=CC=2)C(=O)[N:3]1[CH2:12][CH2:13][N:14]1[C:22]2[C:17](=[CH:18][C:19]([C:23]([O:25][CH2:26][CH3:27])=[O:24])=[CH:20][CH:21]=2)[CH:16]=[N:15]1.NN.C1COCC1>C(O)C.C1COCC1>[NH2:3][CH2:12][CH2:13][N:14]1[C:22]2[C:17](=[CH:18][C:19]([C:23]([O:25][CH2:26][CH3:27])=[O:24])=[CH:20][CH:21]=2)[CH:16]=[N:15]1Ethyl 1-[2-(1,3-dioxoisoindolin-2-yl)ethyl]-1H-indazole-5-carboxylate (step A, 980 mg, 2.7 mmol) was dissolved in ethanol/THF (1:1, 35 mL) under nitrogen. Hydrazine (365 uL) was added and the reaction stirred 17 hours. THF (75 mL) was added and the resulting solids were filtered off. The filtrate was concentrated to an orange solid, which was purified by flash chromatography (dichoromethane/5% methanol/0.5% triethylamine). The product fractions were combined and concentrated to an orange solid (404 mg, 66%). LRMS (ES): 234.1 ([M+H]+, 100%).
Loading…
