Quinone derivatives from the rhizomes of Acorus gramineus and their biological activities.

A further phytochemical investigation of the rhizomes of Acorus gramineus afforded three new quinone derivatives (1-3), together with two known compounds (4 and 5). The identification and structural elucidation of these new compounds were based on 1D and 2D NMR (COSY, HMQC, HMBC and NOESY) and MS data. The absolute configurations were established on the basis of their circular dichroism (CD) data. To investigate the anti-neuroinflammatory effects of the isolated compounds (1-5), the nitric oxide (NO) production was evaluated in the lipopolysaccharide-activated microglia cell line, BV-2. Compounds (1-5) were also tested for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) in vitro by using the SRB assay.