Euphormins A and B, New Pyranocoumarin Derivatives from Hayata, and Their Anti-Inflammatory Activity.

Euphormin-A () and euphormin-B (), two new pyranocoumarin derivatives, and forty known compounds (-) were isolated from Hayata (Euphorbiaceae). The chemical structures of all compounds were established based on spectroscopic analyses. Several isolates were evaluated for their anti-inflammatory activity. Compounds , , , , , and significantly inhibited against superoxide anion generation and elastase release by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Furthermore, compounds and displayed the most potent effects with IC values of 0.68 ± 0.18 and 1.39 ± 0.12 µM, respectively, against superoxide anion generation when compared with the positive control (2.01 ± 0.06 µM).