Benzyl 3-dehydr-oxy-1,2,5-oxadiazolo[3',4':2,3]oleanolate.

The title compound, C(37)H(50)N(2)O(3), is a benzyl ester derivative of oleanolic acid, a penta-cyclic triterpene, with a five-membered oxadiazole ring fused to the ring A. The triterpene A and C rings adopt slightly distorted half-chair conformations, whereas the remaining three six-membered rings are in chair forms.