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Andropanolide and isoandrographolide, minor diterpenoids from Andrographis paniculata: structure and X-ray
Swapan Pramanick1, Sukdeb Banerjee, Basudeb Achari
1Indian Institute of Chemical Biology, Kolkata, India.
Abstract:
Phytochemical investigation of the leaves of Andrographis paniculata has led to the isolation of a new labdane type diterpenoid, andropanolide (1), along with seven known diterpenoids including isoandrographolide (2), previously reported as a rearrangement product of andrographolide. The structures and stereochemistry of compounds 1 and 2 were established by X-ray crystallographic analysis.
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