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Published on: September 16, 2013
Isolation and characterization of the acid and base degradation products of andrographolide
Abstract:
Andrographolide was subjected to degradation under acidic and basic conditions. Three degradation products including two novel compounds, 8,9-didehydroandrographolide (AG-A) and 15-seco-andrographolide (AG-B2), and a known product, 14-deoxy-11,12-didehydroandrographolide (AG-B1), were isolated by chromatography and identified on the basis of their NMR and MS data. The degradation product, AG-A, may result from the isomerization of andrographolide under acidic conditions whereas the base degradation products, AG-B1 and AG-B2, were formed most likely due to the dehydration of allyl alcohol and the hydrolysis of andrographolide at the lactone ring, respectively.
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