Page 150 - phytochemistry I - PharmD Clinical

C-C glycosides:
• Aloin glycosides is another group of glycosides present in aloes. They

have a sugar molecule linked to the C10 of an anthrone or an anthranol
moiety by a C-C covalent bond.
• Aloins are very resistant to hydrolysis, and are not easily oxidized (like
other anthrones and anthranols) to the corresponding anthraquinones.
• The most important representative glycosides are barbaloin and
chrysaloin. Barbaloin is the C10-C-glucoside of aloe-emodin anthrone,
while chrysaloin is the C10-C-glucoside of chrysophanol anthrone.

1. Cascara

The bark of Rhamnus purshiana belonging to the family rhamnaceae. It
is collected one year before use.
Chemical constituents:

a. Anthracene C- glycoside comprising Cascaroside A and B
(Barbaloin), Cascaroside C and D (Chrysaloin),

b. Homo dianthrone of emodin, aloe-emodin and chrysophenol.
c. Emodin, aloe-emodin and chrysophenol as free aglycone.

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