World Journal of Organic Chemistry
ISSN (Print): 2372-2150 ISSN (Online): 2372-2169 Website: Editor-in-chief: Subrata Shaw
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World Journal of Organic Chemistry. 2020, 8(1), 1-4
DOI: 10.12691/wjoc-8-1-1
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Formation Mechanism of the Colored Compounds Derived from Eserine (Physostigmine)

Francisco Sánchez-Viesca1, and Reina Gómez1

1Organic Chemistry Department, Faculty of Chemistry, National Autonomous University of Mexico, Mexico City (CDMX), Mexico

Pub. Date: January 07, 2020

Cite this paper:
Francisco Sánchez-Viesca and Reina Gómez. Formation Mechanism of the Colored Compounds Derived from Eserine (Physostigmine). World Journal of Organic Chemistry. 2020; 8(1):1-4. doi: 10.12691/wjoc-8-1-1


Physostigmine (eserine) is an indole alkaloid isolated from a plant of Western Africa. It is interesting due its striking properties: a potent venom and a drug for open-angle glaucoma treatment. It gives two color reactions, a dark red due to rubreserine, a three ring o-quinone, and a seven ring phenoxazone with a splendid blue color. Though the structures of these compounds have been determined, there is no reaction mechanism related to their formation. We provide the reaction pathway and the electron flow for each reaction. Especially interesting is the case of eserine blue, to know how the molecule is integrated through many reaction intermediates and electron shifts.

Calabar bean eserine blue indole alkaloid physostigmine reaction intermediates reaction mechanisms

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