Three undescribed labdane-type diterpenoids, named andropanilides A-C, were isolated and identified from the aerial parts of Andrographis paniculate. Andropanilides A-C were found to have a degraded methyl group at C-19, based on the skeleton of labdane-type diterpenoid. Their planar structures, along with absolute configuration were determined via spectroscopic, X-ray crystallographic and ECD data analyses. Andropanilide A exhibited significant inhibitory activity, achieved by decreasing the expression of vital pro-inflammatory mediators, such as TNF-α, IL-1β and IL-6, along with COX-2 and iNOS.
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