Biosynthesis Strychnine

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strychnine terpene indole alkaloid belonging strychnos family of corynanthe alkaloids, , derived tryptamine , secologanin. enzyme, strictosidine synthase, catalyzes condensation of tryptamine , secologanin, followed pictet-spengler reaction form strictosidine. while enzymes catalyze following steps have not been identified, steps have been inferred isolation of intermediates strychnos nux-vomica. next step hydrolysis of acetal, opens ring elimination of glucose (o-glu) , provides reactive aldehyde. nascent aldehyde attacked secondary amine afford geissoschizine, common intermediate of many related compounds in strychnos family.


a reverse pictet-spengler reaction cleaves c2–c3 bond, while subsequent mannich reaction forms c3–c7 bond, , michael addition forms c2–c16 bond provide dehydropreakuammicine. hydrolysis of methyl ester , decarboxylation leads norfluorocurarine. stereospecific reduction of endocyclic double bond nadph , hydroxylation provides wieland-gumlich aldehyde, first isolated heimberger , scott in 1973, although synthesized wieland , gumlich in 1932. elongate appendage 2 carbons, acetyl-coa added aldehyde in aldol reaction afford prestrychnine. strychnine formed facile addition of amine carboxylic acid or activated coa thioester, followed ring-closure via displacement of activated alcohol.








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