Synonyms: (2E,4E,6E,8E)-3,7-dimethyl-9-(2,6,6-trimethyl-3-oxo-1-cyclohexenyl)nona-2,4,6,8-tetraenoic acid;4-oxo-Retinoic acid;all-trans 4-Keto Retinoic Acid;(E)-3,7-Dimethyl-9-(2,6,6-trimethyl-3-oxo-1-cyclohexen-1-yl)-2,4,6,8-nonatetraenoic acid;4-Ketoretinoic acid;4-Oxo-all-trans-retinoic acid;Retinoic acid, 4-oxo-;Ro 12-4824