Aspidosperma limae

The three alkaloids named in the title (XXXII, XXXIII, and XXXIV) are respectively the A -formyl, -acetyl, and -propionyl derivatives of aspidospermidine (Section II, E). Demethoxypalosine (XXXIV) has been isolated from Aspidosperma limae (40) and A. discolor (40a) and was characterized as an iVa-acyldihydroindole by its UV-spectrum (Table III) and IR-absorption at 5.89 p. A strong band in the IR-spectrum at 13.1 p indicated an unsubstituted benzene ring. The foregoing information was confirmed and the substance was shown to belong to the aspidospermine group by NMR- and mass spectrometry. In the NMR-spectrum (Table IV) the 17-proton absorption is found at 8.13 well downfield from the three-proton multiplet due to the other aromatic protons which is centered at 7.07 8. This shift is due to the proximity of the carbonyl group of the iVa-propionyl group. In the aliphatic part of the spectrum, absorptions which are characteristic of the... 

From the leaves of Pleiocarpa tubicina, in addition to bases described in Sections III, G, and VI, C, there has been isolated an alkaloid, tubotaiwine, of structure CCXXIV (119). The same substance also occurs in the root bark of Aspidosperma limae (120). 

The 11-methoxy derivatives (CCLXa) and (CCLXb) recently isolated from Aspidosperma limae (37a) have the same absolute configurations. 

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