Eight new flavonoids daemoflavans A-H, including two dimeric proanthocyanidins (1 and 2), four flavans (3-6), two 2-arylbenzofurans (7 and 8), along with nine known compounds (9-17), were isolated from the fruit of Daemonorops draco. Their structures, including the absolute configurations, were elucidated by extensive spectroscopic data, ECD analysis, and X-ray crystal diffraction. Besides, the X-ray crystal data of a known compound dracoflavan B1 (9) was firstly reported. Daemoflavan G (7) represents a rare example of C-5 methylated 2-arylbenzofuran in natural products. Among the known compounds, 15, 16, 17 were reported from this species for the first time. All the compounds were evaluated for their cytotoxicity against HepG2 cell line. Among them, compounds 1, 9 and 10 exhibited modest cytotoxic activity with IC50 values of 12.4, 12.0 and 13.2 μM, respectively.
Keywords: Cytotoxicity; Daemonorops draco; Dragon's blood; Flavonoid.
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