.alpha.-Retinene 116-31-4 2,4,6,8-Nonatetraenal, 3,7-dimethyl-9-(2,6,6-trimethyl-1- cyclohexen-1-yl)-, (all-E)- Axerophthal E-Retinal NSC20811 Retinal Retinal, all-trans- Retinene 1 Vitamin A1 aldehyde all-trans-Retinaldehyde all-trans-Vitamin A aldehyde trans-Retinal