39071-33-5 Euphorbia factor I Hexadecanoic acid, (1a,2,5,5a,6,9,10,10a-octahydro-5,5a,6-trihydroxy-1,1,7,9-tetramethyl-11-oxo-1H-2,8a-methanocyclopenta(a)cyclopropa(e)cyclodecen-4-yl)methyl ester, (1aR-(1aalpha,2alpha,5beta,5abeta,6beta,8aalpha,9alpha,10aalpha))-