Eserine synthesis pathway

Eserine (physostigmine) has a pyrroloindole skeleton. This alkaloid is used as an anticholinesterase drug, which is fairly important in the treatment of Alzheimer s disease. Eserine is synthesized in Physostigma venenosum and stored in the seeds of this leguminous plant. The synthesis pathway starts with tryptamine, which is transformed into eserine (Eigure 45). 

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A.6 Quinine, quinidine, and cinchonine synthesis pathway 123 2.2.4.7 Eserine synthesis pathway 124... 

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