20-O-Isobutyryl-3-O-propionylingenol 74690-92-9 Ingenol-3-propionate-20-isobutyrate Ingenol-pib Propanoic acid, 2-methyl-, (1a,2,5,5a,6,9,10,10a-octahydro-5,5a-dihydroxy-1,1,7,9-tetramethyl-11-oxo-6-(1-oxopropoxy)-1H-2,8a-methanocyclopenta(a)cyclopropa(e)cyclodecen-4-yl)methyl ester, (1aR-(1aalpha,2beta,5beta,5abeta,6beta,8aalpha,9alpha,10aalpha))-