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.