Antimitotic activity of glaupalol-related coumarins from Glaucidium palmatum

Two new coumarins, glaumacidines A (1) and B (2), and the related coumarins (3–7) have been isolated from the rhizomes of Glaucidium palmatum (Glaucidiaceae). The absolute configurations of 1 and 2 and trans- and cis-glaupadiols (3 and 4, respectively) were elucidated by spectroscopic data, chemical derivatization, and exciton chirality method. Glaupalol (5) enhanced the polymerization of tubulin and affected synergistically with paclitaxel on inhibition of KB cell proliferation.