Strychnine (SN)

Strychnine is a terpene indole alkaloid belonging to the Strychnos family of Corynanthe alkaloids, and it is derived from tryptamine and secologanin. The enzyme, strictosidine synthase, catalyzes the condensation of tryptamine and secologanin, followed by a Pictet-Spengler reaction to form strictosidine. While the enzymes that catalyze the following steps have not been identified, the steps have been inferred by isolation of intermediates from Strychnos nux vomica. The next step is hydrolysis of the acetal, which opens the ring by elimination of glucose (O-Glu) and provides a reactive aldehyde. The nascent aldehyde is then attacked by a secondary amine to afford geissoschizine, a common intermediate of many related compounds in the Strychnos family. Strychnine may be introduced into the body orally, by inhalation, or by injection. It is rapidly absorbed from the gastrointestinal tract.