Antimitotic activity of lobaric acid and a new benzofuran, sakisacaulon A from Stereocaulon sasakii.

Lobaric acid (1) has been isolated from lichen, Stereocaulon sasakii together with a new benzofuran, sakisacaulon A (2). Lobaric acid (1) inhibited the polymerization of tubulin. Structure-activity relationship of lobaric acid and its derivatives on inhibitory activity of tubulin polymerization was discussed.

Antimitotic activity of two macrocyclic bis(bibenzyls), isoplagiochins A and B from the Liverwort Plagiochila fruticosa.

Two bis(bibenzyls), isoplagiochins A (1) and B (2) have been isolated by the guidance of inhibitory effect of tubulin polymerization from the liverwort Plagiochila fruticosa (Plagiochilaceae). Isoplagiochins A and B inhibited the polymerization of tubulin at IC(50) 50 and 25muM, respectively. Furthermore structure-activity relationship based on their conformations was discussed.