The 13C NMR spectra of some tertiary and quaternary aporphine alkaloids are recorded and the signals assigned. The substituent shielding effects together with the effects of N- and O-methylation, and the twisting of the biphenyl system, are analysed and utilized in the spectral interpretation.

The alkaloids of seven of the eight species of Fagara growing in Argentina have been investigated. All the bases isolated and characterized were quaternary and belonged either to the simple phenylethylamines or to the benzylisoquinolines. In the last group one benzylisoquinoline, several aporphines, two berberines and two benzophenanthridine alkaloids were identified (Table 1). Two of them, tembetarine and N-methylcorydine were found for the first time in plants. Some considerations are made on the distribution of these alkaloids among Fagara and Zanthoxylum species.

S. M. Albónico, A. M. Kuck and V. Deulofeu, J. Chem. Soc. C, 1967, 1327 DOI: 10.1039/J39670001327

The relationship between the optical rotatory dispersion and absolute configuration of quaternary 1-benzyltetra-hydroisoquinolines and aporphines has been shown to be the same as that for the tertiary bases.

AbstractAus der Rinde von Fagara naranjillo (Griseb.) Engler wird eine neue quartäre Benzylisochinolin‐Base, (+)‐Tembetarin (I), isoliert. Sie leitet sich durch N‐Methylierung von der entsprechenden tertiären Base, dem (+)‐Reticulin, ab. I wird durch Oxydation in eine Aporphin‐Base, das (+)‐Laurifolin (IX), übergeführt.