Ibogaine from Tabemanthe iboga

Further variants on the terpenoid indole alkaloid skeleton (Figure 6.82) are found in ibogaine from Tabemanthe iboga, vincamine from Vinca minor, and ajmaline from Rauwolfia serpentina. Ibogaine is simply a C9 Iboga type alkaloid, but is of interest as an experimental drug to treat heroin addiction. In a number of European countries, vincamine is used clinically as a vasodilator to increase cerebral blood flow in cases of senility, and ajmaline for cardiac arrhythmias. Ajmaline... 

Ibogaine was isolated in 1901 from Tabemanthe iboga roots by Dybowski and Landrin and by Haller and Heckel. The most abundant alkaloid in the shrub s root bark, ibogaine exhibts the indole nucleus structure common to most psychedelics. Its stereochemistry (the dotted lines are at angles to the rest of the molecule) was established in the late 1960s ... 

Ibogaine, the most studied of the alkaloids present in the roots of Tabemanthe iboga, is representative of another cluster of indolic molecules that have been included among psychedelics. Ibogaine is a naturally occurring compound of special interest because it comes from an entirely different botanical family than anything discussed above—a contribution to the mystery of psychedelics from equatorial Africa. 

Through a biomimetic approach, tabersonine is also the semisynthetic precursor of vincamine, a Eburna alkaloid isolated from Vinca minor, and is used for cerebral insufficiency in Europe. Tabemanthe iboga has a long history of use as a stimulant in tropical Africa its main active principle is ibogaine, a controlled substance in many countries (Fig. 40). It is being actively investigated in the United States for its potential to induce opium addiction withdrawal. 

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