反应详情

9H-β-carboline-3-carboxylic acid ethyl ester (20 g, 833 mmol) was slowly added to concentrated nitric acid (400 mL). The reaction mixture was stirred at 70°-75° C. for 2 h. After cooling to room temperature the resulting mixture was poured onto ice (1 kg). The precipitated compound was collected, and recrystallized from pyridine (650 mL). This afforded the title compound (14.9 g, 63%). M.p. 339°-341° C.

1. additionwas poured onto ice (1 kg)
2. customThe precipitated compound was collected
3. customrecrystallized from pyridine (650 mL)