Common in fungi as well as higher plants

ANTHRACENE

derivatives are based on a three ring system.

They are substituted by oxygen as hydrolysed groups like;

The cyclisation of an octaketide produces Emodine - anthrone

eight acetate units linked together.

A number of glycosides with aglycones related to anthracene are present in such drugs as

These drugs are employed as cathartics. The glycosides, upon hydrolysis, yield aglycones that are di-, tri- or tetra- hydroxy anthraquinones or modifications of these compounds.

The free anthraquinone aglycones exhibit little therapeutic activity. The sugar residue facilitates absorption and translocation of the aglycone to the site of action. The anthraquinone and related glycosides are stimulant cathartics and exert their action by increasing the tone of the smooth muscle in the wall of the large intestine.

Glycosides of anthranols and anthrones elicit a more drastic action than do the corresponding anthraquinone glycosides.

FRIEDLI ENTERPRISES
Georges-Louis Friedli, MSc,PhD.
georges-louis@friedli.com