WF11605, an antagonist of leukotriene B4 produced by a fungus. II. Structure determination.

The structure of WF11605, a novel tetracyclic triterpene glucoside, was determined to be 1. The plane structure of deacetyl-WF11605 aglycone was elucidated as 2 through the concerted application of a series of 2D NMR techniques. The relative configurations were established by X-ray crystallographic analysis of bis(p-bromobenzoyl) derivative 3 and absolute stereochemistry by CD exciton chirality method.