Reversible inhibitor of vesicular trafficking between endoplasmic reticulum and Golgi apparatus. Modifies Golgi ADP-ribosylation factor (ARF)1 GTPase activity and inhibits exocytosis (IC 50 ~ 20 mM). Has similar, but not identical, action to brefeldin A (1,6,7,8,9,11ab,12,13,14,14aa-Decahydro-1b,13a-dihydroxy-6b-methyl-4H-cyclopent(f)oxacyclotridecin-4-one ).