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Two new polyketides from the roots of Stemona tuberosa
Lei Fang1, Xiu-Qing Song1, Tian-Tian He1
1School of Biological Science and Technology, University of Jinan, Jinan 250022, China.
Abstract:
Two polyketides, stemonones A (1) and B (2) with new skeletons, were isolated from the roots of Stemona tuberosa. Their absolute structures were fully characterized by comprehensive spectroscopic analyses and comparison of experimental electronic circular dichroism (ECD) spectra with calculated ones. The plausible biosynthetic pathways for 1 and 2 were also proposed. Anti-inflammatory assay confirmed that the two compounds showed moderate inhibitory effects on β-glucuronidase release in rat polymorphonuclear leukocytes (PMNs) induced by platelet-activating factor.
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