New steroidal alkaloids from Fritillaria imperialis and their cholinesterase inhibiting activities

Abstract

Two new cevanine steroidal alkaloids, impericine (1) and forticine (2) along with known bases delavine (3), persicanidine A (4), and imperialine (5) were isolated from the bulbs of Fritillaria imperialis. The structures of impericine (1) [(20R,22S,25S)-5α-cevanin-23-ene-3β,6β,16β- triol] and forticine (2) [(20S,22S,25S)-5α-cevanine-3β,6β-diol] were determined with the help of spectroscopic studies. These steroidal bases showed anti-acetylcholinesterase and anti-butyrylcholinesterase inhibitory activity. © 2002 Pharmaceutical Society of Japan.