Semi-synthesis method of aristololactam

[0018] Preparation of AL I: Dissolve about 10 mg of AA I in 50 ml of methanol, slowly add to 30 ml of 0.15 mol / L hydrochloric acid and 200 mg of reduced iron powder, stir and N 2 React under protection for 30 min. The reaction temperature is set at 70-80°C. During the reaction, hydrochloric acid was added dropwise to keep the pH=1. After the reaction is complete, filter while hot, adjust the pH to 5 with ammonia water, add 30 ml of ethyl acetate, shake for 1 minute, and let stand to separate layers. After extraction twice, the ethyl acetate layers were combined, and the ethyl acetate was blown dry with nitrogen to obtain yellow crystals, namely ALI, about 9.5 mg. Using HPLC-UV detection, in terms of chromatographic peak area, the purity of the prepared ALI is not less than 98%.

[0020] Preparation of AL II: Dissolve about 5 mg of AA II in 50 ml of methanol, add 15 ml of 0.15 mol / L hydrochloric acid and 100 mg of reduced iron powder, and react for 30 min under stirring and N2 protection. The reaction temperature is set at 70-80°C. During the reaction, hydrochloric acid was added dropwise to keep the pH=1. After the reaction is complete, filter while hot, adjust the pH to 5 with ammonia water, add 20 ml of ethyl acetate, shake for 1 minute, and let stand to separate layers. After extraction twice, the ethyl acetate layers were combined, and the ethyl acetate was blown dry with nitrogen to obtain yellow crystals, namely AL II, about 4.8 mg. Using HPLC-UV detection, in terms of chromatographic peak area, the purity of the prepared AL II is not less than 98%.