Page 119 - phytochemistry II -pharmD general
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Gallotannins
Pentagalloyl glucose, has five identical ester linkages that involve aliphatic
hydroxyl groups of the core sugar.
Alkalies, acids, or enzymes like tannase hydrolyze the ester linkages to give
gallic acid and glucose
Pentagalloyl glucose
Ellagitannins
✓ Formed by intramolecular C-C oxidative coupling between two gallic
acids
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