New Flavone C-Glycosides from and Their Anti-Collagenase Activity

Three new flavone glycosides, one known flavone glycoside, and the phenolic derivative apiopaenonside were isolated and identified from the ethyl acetate fraction of the aerial parts of . The planar structures were elucidated through extensive analysis of UV-Vis, IR, and H NMR and C NMR spectral data, including the 2D techniques COSY, HSQC, and HMBC, as well as ESI mass spectrometry. The isolated compounds were established as 5,7,3'-trihydroxy-4'-acetoxyflavone-8---d-xylopyranoside-2''--glucoside (), 5,7,3'-trihydroxy-4'-methoxyflavone-8--d-xylopyranoside-2''--glucoside (), 5,7-dihydroxy-3'-methoxy-4'-acetoxyflavone-8---d-xylopyranoside-2''--glucoside (), 5,7-dihydroxy-3'-methoxy-4'-acetoxyflavone-8---d-xylopyranoside-2''--(4'''-acetoxy)-glucoside (), and apiopaenonside (). Moreover, all isolated compounds were evaluated for anti-collagenase activity. All compounds exhibited moderate inhibitory activity with IC values ranging from 36.06 to 70.24 µM.