Page 148 - phytochemistry I - PharmD Clinical

tautomeric forms (isomers) and converted to one another in solution
by tautomerism.
Glycosides of anthranols, dianthrones, and oxanthrones have significant
therapeutic action.

Chemical test for anthraquinone glycosides:

Borntrager’s test:
This test is specific for aglycone, therefore hydrolysis with HCl in
case of O-glycosides must be performed.
Powdered plant material is mixed with organic solvent and filtered.
Aqueous base (NaOH or NH4OH) is added to the organic layer. A
pink or violet color in the base layer indicates the presence of
anthraquinone nucleus.
Modified borntrager’s test:
In case of C-glycosides, it must be first hydrolysed using ferric
chloride/HCl for (oxidative hydrolysis).
This test distinguished anthraquinones from anthones and
anthranols
Anthones and anthranoles give negative Borntragers test unless
oxidized to anthraquinones using mild oxidant as hydrogen
peroxide.
Monomers of anthracene derivatives:
These monomers are the aglycones formed after hydrolysis of
anthraquinone glycosides. They all differ in the substituents and these

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