Retinoids and Related Compounds. X. : Synthesis of Geometrical Isomers of (±)-2- and (±)-3-Hydroxyretinals and Identification of the Chromophone of the Fly Visual Pigment

Abstract

The geometrical isomers of (±)-3-hydroxyretinals were synthesized and characterized. Subsequently, simultaneous separation of eight isomers of 2- and 3-hydroxyretinals by high-performance liquid chromatography (HPLC) was accomplished and, in addition, complete separation of eight syn-anti isomers of 3-hydroxyretinaloximes by HPLC was achieved. Under these analytical conditions, the chromophore of the fly (Drosphila melanogaster) visual pigment was identified as 11-cis-3-hydroxyretinal (10).