Hasubanan type alkaloids from Stephania longa.

Thirteen new hasubanan type alkaloids, stephalonines A-I (1-9), norprostephabyssine (15), isoprostephabyssine (16), isolonganone (18), and isostephaboline (21), as well as nine known ones, were isolated from the whole plants of Stephania longa, a well-known traditional Chinese medicine. Their structures were elucidated on the basis of spectroscopic data and chemical methods.