Synonyms: 5H-Cyclopropa[3,4]benz[1,2-e]azulen-5-one,1,1a,1b,4,4a,7a,7b,8,9,9a-decahydro-4a,7b,9,9a-tetrahydroxy-3-(hydroxymethyl)-1,1,6,8-tetramethyl-,[1aR-(1aa,1bb,4aa,7aa,7ba,8a,9b,9aa)]-; 5H-Cyclopropa[3,4]benz[1,2-e]azulen-5-one, 1,1aa,1bb,4,4a,7aa,7b,8,9,9a-decahydro-4aa,7ba,9b,9aa-tetrahydroxy-3-(hydroxymethyl)-1,1,6,8a-tetramethyl- (8CI); 4a-Phorbol; Isophorbol; a-Phorbol