2,4-Pentanedione, 3-(3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4,6,8-nonatetraenylidene)-, (all-E)- 3-(3,7-Dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4,6,8-nonatetraenylidene)-2,4-pentanedione (all-E)- 3-Retinylidene-2,4-pentanedione, trans- 6991-16-8