Tabersonine is a terpene indole alkaloid found in the medicinal plant Catharanthus roseus and also plants in the genus Voacanga (both taxa belonging to the alkaloid-rich family Apocynaceae). Tabersonine is hydroxylated at the 16 position by the enzyme tabersonine 16-hydroxylase to form 16-hydroxytabersonine. Tabersonine is the first intermediate leading to the formation of vindoline one of the two precursors required for vinblastine biosynthesis.

Biosynthesis

Tabersonine is an indole alkaloid whose immediate precursor in Catharanthus roseus (Madagascar periwinkle) is the compound dehydrosecodine. This is cyclised by the enzyme tabersonine synthase:

The biosynthetic pathway to vindoline and vinblastine continues when tabersonine is hydroxylated by the enzyme tabersonine 16-hydroxylase, giving 16-hydroxytabersonine:

See also