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Clinical pharmacy PharmD program Third level Phytochemistry-1 (PG-504)
6-Desoxyhexose L-Fucose L-Rhamnose
Occurrence in Gum tragacanth. Gum Arabic
nature
General Tests:Aniline acetate paper: yellow stain (pentose give red).
L-Rhamnose
It is a 6-desoxy-L-mannose, present in
plant kingdom as glycoside.
It can be prepared from lemon flavin,
obtained from Quercus tinctoria, by acid
hydrolysis, neutralization, decolorization,
concentration and finally crystallization.
b) 2,6-Didesoxy-sugars
The carbohydrates parts of cardiac glycosides
are in most cases belonging to 2, 6-desoxy-hexoses.
In case of 2, 6-desoxy-hexoses the hydroxyl-groups
at C-2 and at C-6 are reduced. Examples of the 2, 6-
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