(4S,10S)-1,4,6a,6b,9,9,12a-heptamethyl-13-oxo-10-[(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)oxy]-1,2,3,4,4a,5,6,6a,6b,7,8,8a,9,10,11,12,12a,12b,13,14b-icosahydropicene-4-carboxylic acid