Coronaridine subtype

Coronaridine subtype alkaloids are widely spread in Tabernaemontana. The iboga skeleton is particularly susceptible to oxidation at aminomethylenes C-3 and C-5 and at benzylic C-6. Very often, the fundamental compounds are accompanied by the oxidation products at these positions. 

Tabernaemontana eglandulosa is a small liane distributed in the forests of cehtral Africa. The root bark yielded many coronaridine-subtype alkaloids, whereas the leaves afforded the already discussed (145, 20/ )-velbanamine (160), some new pseudotabersoninelike alkaloids, and many other structurally new compounds discussed later. 

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