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Constituents:
Cascara contains about 6-9% anthracene derivatives as normal O-
glycosides and C-glycosides.
Anthracene glycosides are a number of glycosides in which the
aglycones are anthracene derivatives, occurring as the
pharmacologically active constituents of several cathartics of plant
origin.
1- Four primary glycosides or cascarosides A, B, C and D.
2- Two aloins : barbaloin and chrysaloin.
3-Aloe-emodin, crysophanol and emodin in the free state.
In the fresh bark, anthraquinones are present in the reduced form, and are
converted by oxidation from their corresponding parent anthraquinone
glycosides during drying and storage.
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