Fluorinated Retinoids and Carotenoids

Methods of preparing fluorinated retinoids with labels located on odd-numbered carbons as well on even-numbered carbons and those containing trifluoromethyl groups are reviewed. The use of such retinoids in studies of protein-bound species is summarized, including the application of F-19 NMR spectroscopy for elucidating the mechanism of cis/trans isomerization, restricted rotation within the protein binding pocket, and identification of specific protein substrate interactions. The fluorine label was also useful for wavelength attenuation of protein-bound species (including formation of NIR absorbing pigments) and for other unique. applications. The more limited studies available on fluorinated carotenoids are also reviewed.