Synonyms: Butanoicacid,(1aR,1bS,4aS,7aS,7bS,8R,9R,9aS)-1,1a,1b,4,4a,5,7a,7b,8,9-decahydro-4a,7b-dihydroxy-3-(hydroxymethyl)-1,1,6,8-tetramethyl-5-oxo-9aH-cyclopropa[3,4]benz[1,2-e]azulene-9,9a-diylester (9CI); Butanoic acid,1,1a,1b,4,4a,5,7a,7b,8,9-decahydro-4a,7b-dihydroxy-3-(hydroxymethyl)-1,1,6,8-tetramethyl-5-oxo-9aH-cyclopropa[3,4]benz[1,2-e]azulene-9,9a-diylester, [1aR-(1aa,1bb,4aa,7aa,7ba,8a,9b,9aa)]-;9aH-Cyclopropa[3,4]benz[1,2-e]azulene, butanoic acid deriv.; 4a-Phorbol 12,13-dibutyrate; 4a-Phorbol dibutyrate