反应详情

A mixture of Step 4 intermediate (130 mg, 0.491 mmol) and concentrated hydrochloric acid (4 mL) was heated at 60° C. for 2 h. The excess of hydrochloric acid was evaporated under reduced pressure and the residue obtained was purified by silica gel column chromatography using 5% methanol in chloroform to obtain 94 mg of the product as a white solid; 1H NMR (δ ppm, 300 MHz, DMSO-d6) 3.21 (s, 3H), 3.65-3.72 (m, 8H), 6.29 (s, 1H), 12.62 (br s, 1H); APCI-MS (m/z) 252.38 (M+H)+.

1. customThe excess of hydrochloric acid was evaporated under reduced pressure
2. customthe residue obtained
3. customwas purified by silica gel column chromatography