A Chemical Study of Burley Tobacco Flavour (Nicotiana tabacumL.) V. Identification and Synthesis of the Novel Terpenoid Alkaloids 1, 3, 6, 6-Tetramethyl-5, 6, 7, 8-tetrahydro-isoquinolin-8-one and 3, 6, 6-Trimethyl-5,6-dihydro-7H-2-pyrindin-7-one

GLC. allowed the isolation of 1, 3, 6, 6-tetramethyl-5, 6, 7, 8-tetrahydro-isoquinolin-8-one (A) and 3,6,6-trimethyl-5,6-dihydro-7H-2-pyrindin-7-one (D) from Burley tobacco condensate (about 0.1% each). The structures and syntheses of these novel terpenoid alkaloids are described, and a possible way for their formation in tobacco is suggested.