C-13-nmr chemical shift assignments for the lactone-type diterpenoid a
lkaloids heteratisine [1], 6-acetylheteratisine [3], and 6-benzoylhete
ratisine [2] have been revised on the basis of the study of their 1D,
2D, and selective INEPT nmr spectra. Unambiguous C-13-nmr chemical shi
ft assignments for the related alkaloids heterophyllidine [4], heterop
hylline [5], and heterophyllisine [6], which have not been reported pr
eviously, are reported in this study. Complete H-1-nmr chemical shift
assignments are also reported.