The structures of laurifonine (17)(6, 7, 8, 9-tetrahydro-2, 3, 12-trimethoxy-7-methyl-5-dibenz [,] azonine) laurifine (18)(its 7-demethyl analogue), and laurifinine (19)(its 2-de--methyl analogue) have been established by chemical and spectroscopic studies. The biogenesis of dibenz [,] azonine bases is discussed.