Two new eudesmanolides from Inula racemosa and their bioactivities.

Abstract: Two new eudesmane-type sesquiterpene lactones, 1-one-4-epi-alantolactone (1) and 4α,13-dihydroxy-5,7(11)-eudesmadien-12,8-olide (2), were isolated from the roots of Inula racemosa, together with six known compounds (3–8). The cytotoxic activities against five human cancer cell lines had been tested and compounds 3, 6, 7 and 8 exhibited moderate cytotoxic activities. Compounds 4 and 8 showed potent in vitro activities against the release of β-glucuronidase in rat polymorphonuclear leukocytes (PMNs) induced by platelet-activating factor (PAF), with the inhibitory ratios 65.4% (P <0.01) and 80.5% (P <0.001), at concentration of 10μM, respectively. [Copyright &y& Elsevier]