Stemmadenine

Stemmadenine is a terpene indole alkaloid. Stemmadenine is believed to be formed from preakuammicine by a carbon-carbon bond cleavage. Cleavage of a second carbon-carbon bond is thought to form dehydrosecodine. The enzymes forming stemmadenine and using it as a substrate remain unknown to date. It is thought to be intermediate compound in many different biosynthetic pathways  such as in Aspidosperma species. Many alkaloids are proposed to be produced through intermediate stemmadenine. Some of them are: It is also present as product in plant like in Tabernaemontana dichotoma seeds.
 * Catharanthine and Tabersonine in Catharanthus roseus
 * Subincanadines D-F in Aspidosperma subincanum

Pharmacology
It has hypotensive and weak muscle relaxant properties.