Page 153 - phytochemistry I - PharmD Clinical

Chemical Constituents:
Sennosides A, Sennoside B,Sennoside C and Sennoside D
Aloe-emodin and rhein glycosides.

Storage effect on anthracene glycosides:

• Prolonged storage causes oxidation of anthrones and anthranols to
give the relatively less drastic anthraquinones. Thus, the degree of
drastic activity of drug decrease with time. Anthrones and
anthranols are more potent than their corresponding oxanthrones.
Oxanthrones in turn are more active than their corresponding
anthraquinones.

• The order of decreasing activity:

Anthrones and anthranols > Dianthrones > Anthraquinones

• Glycosides of anthranols and anthrone (Aloe and Rhubarb) elicit
a more drastic action than other anthraquinone leading to
discomforting gripping action. The drug of choice is cascara and
senna.

• The action of senna is due to presence of the glycosides (sennoside
A and B).

• Cascara and senna have been approved by the U.S. Food and Drug
Administration for adults and children older than 2 years for bowel
preparation and constipation.

Uses of anthracene glycosides:

Cathartic (Promoting active movement of bowels). It rectifies the habitual
constipation where it is does not only act as a laxative but restores natural
tone the colon.

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