Chemical Constituents from the Roots and Rhizomes of Asarum heterotropoides var. mandshuricum and the In Vitro Anti-Inflammatory Activity

摘要

Anti-inflammatory compounds were investigated from the ethanol extract of the roots and rhizomes of Asarum heterotropoides var. mandshuricum, a traditional Chinese medicine called Xixin and used for pain and inflammatory. Nine new compounds were isolated, including six new lignans, neoasarinin A–C (>1–>3), neoasarininoside A and B (>4 and >5), and asarinin B (>7), and one new monoterpene, asarincin A (>8), two new amides, asaramid II and III (>10 and >11), and one new natural monoterpene, asaricin B (>9), along with 37 known compounds (>6, >12–>47). Their structures and absolute configurations were elucidated on the basis of spectroscopic methods and chemical analyses. This is the first report of the absolute configuration of asarinin A (>6). The 8-O-4′ neolignans (>1–>5) were reported in the genus Asarum for the first time. The 15 compounds >17, >19, >22–>25, >28, >31, >36, >40, >42, >43, >45–>47 were isolated from the genus Asarum, and compounds >16, >32, >33, >37 and >39 were isolated from A. heterotropoides var. mandshuricum for the first time. Thirty-seven of the isolates were evaluated for anti-inflammatory activity against the release of β-glucuronidase in polymorphonuclear leukocytes (PMNs) induced by the platelet-activating factor (PAF), and compounds >1, >4, >7, >8, >14, >17–>19, >22, >24, >25, >29, >30, >32, >33, >40–>43, >45, and >46 showed potent anti-inflammatory activities in vitro, with 27.9%–72.6% inhibitions at 10⁻⁵ mol/L. The results of anti-inflammatory assay suggested that lignans obtained from the CHCl3 extract might be the main active components of Xixin.