Amsonia tabernaemontana

Tabersonine (XCII), an amorphous base which occurs in the seeds of Amsonia tabernaemontana (65, Volume VII, p. 134), in some Stem-madenia species (66, 66a), and in Tabernaemontana alba (66a), is a member of a distinct group of aspidospermine-type alkaloids which bear an extra carbon atom in the form of a carbomethoxyl group linked to position 3. The other members of this group are described briefly in Section II, P and in detail in Chapter 12. 

Aspidospermine-Aspidofractine-Eburnamine Group. The leaves of Pandaca minutiftora contain (+)-vincadifformine, which also occurs in the leaves of Amsonia tabernaemontana, together with ten other alkaloids [tabersonine, (+)-l,2-dehydroaspidospermidine, (—)-quebrachamine, lochnericine, ( ) and (—)-vincadine, (-)and ( )-epivincadine, (+)-14,15-dehydrovincadine, and (+)-14,15-dehydroepivincadine] the roots contain the first four alkaloids and ebumamonine. 

Eburnamine-Aspidospermine Group. 14,15-Dehydrovincamine and its C-16-epimer have been obtained " from Crioceras longiflorus, and their 11-methoxy-analogues, the C-16 epimeric 14,15-dehydrovincines, have been obtained from Craspidospermum verticillatum. A mixture of (—)- and ( )-vincadine has been isolated from Amsonia tabernaemontana. 

Amsonia elliptica Roem. et Schult. Amsonia tabernaemontana Walt Aspidosperma album Vahl. (R. Benth. ex M. Pichon)... 

Eburnamine has been recognized in Gonioma kamassi E. May 15) and the same compound, isoeburnamine, eburnamonine, the indoles, base A (mp 229°-230°), base B (mp 246°-247.5° decomp.), base V (mp 224°-225° decomp.), and the dihydroindole, base G (mp 115°-116.5°) have been obtained from Amsonia tabernaemontana Walt. (Amsonia salicifolia Pi chon) 16). 

For the industrial semisynthesis of vincamine, tabersonine is used. This alkaloid among others is found in the seeds of Amsonia tabernaemontana. Petiard et al. (722) reported callus cultures of this plant, but no further... 

Strictosidine (104) is produced by the plant Rhazya stricta. A crude enzyme preparation from the plant was used to produce labelled strictosidine this, when incubated with Catharanthus enzyme, again gave the three alkaloids (105), (106), and (107). ° Cell-free preparations of cell-suspension cultures of Amsonia tabernaemontana, Rhazya orientalis, and Vinca minor were also observed to convert (102) plus (103) into strictosidine (104) with fair efficiency the formation of vincoside (109) was never observed. ... 

Tabersonine has been reportedly found in plants belonging to Apocynaceae, e.g., Amsonia tabernaemontana, Amsonia sinensis, Voacanga thouarsii, and Melodinus reticulatus, apart from C. roseus. Tabersonine is extracted from voacanga seeds for commercial purposes [10-12] (Fig. 20.5b). 

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