Indoloquinazoline alkaloids from Euodia rutaecarpa and their cytotoxic activities

Nine indoloquinazoline alkaloids (1–9) were isolated from the dried and nearly ripe fruits of Euodia rutaecarpa (Juss.) Benth. (Euodiae Fructus), along with limonin and β-sitosterol. Their structures were elucidated on the basis of their spectroscopic data. Among them, compounds 1 and 2 were new compounds and characterized as (7R,8S)-7-hydroxy-8-methoxy-rutaecarpine and (7R,8S)-7-hydroxy-8-ethoxy-rutaecarpine, respectively, and 1-hydroxy-rutaecarpine (3) and (7R,8S)-7,8-dihydroxy-rutaecarpine (4) were isolated from Euodiae Fructus for the first time. The nine indoloquinazoline alkaloids were evaluated for their cytotoxic activities against human promyelocytic leukemia HL-60 cells and human gastric carcinoma N-87 cells.