Tabernaemontana eglandulosa

The ninth type, tacaman (class III skeleton) has been added by Verpoorte and van Beek in order to account for the isolation of a few tacamines (see below), new indole alkaloids which until now were found only in Tabernaemontana eglandulosa. 

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. 

Tabernaemontana eglandulosa gave also a very small amount of a mixture of the known (20/ )-pseudovincadifformine (162) and its new (205) epimer 163. The amount isolated was too small for a separation of the epimers, and they were recognized by comparison of the spectral data ( H NMR) with those of a racemic mixture of 162 and 163, synthesized by Kuehne (Scheme 9). (204). 

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