Strictosidine is formed by the Pictet–Spengler reaction condensation of tryptamine with secologanin by the enzyme strictosidine synthase. Thousands of strictosidine derivatives are sometimes referred to by the broad phrase of monoterpene indole alkaloids. Strictosidine is the base molecule for numerous pharmaceutically valuable metabolites including quinine, camptothecin, ajmalicine, serpentine, vinblastine and vincristine. Strictosidine is formed by the Pictet–Spengler reaction condensation of tryptamine with secologanin by the enzyme strictosidine synthase. Thousands of strictosidine derivatives are sometimes referred to by the broad phrase of monoterpene indole alkaloids. Strictosidine is the base molecule for numerous pharmaceutically valuable metabolites including quinine, camptothecin, ajmalicine, serpentine, vinblastine and vincristine. Biosynthetic pathways help to define the subgroups of strictosidine derivatives.