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Is (9Z)-"meso"-zeaxanthin optically active?

B F Lutnaes·O R Gautun·S Liaaen-Jensen
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Abstract

The question raised in the title was answered. (3R, 3'S)-meso-Zeaxanthin was submitted to iodine catalyzed photochemical stereoisomerisation. The enantiomeric (9Z) and (9'Z) geometrical isomers were isolated by semipreparative HPLC and separated as diastereomeric dicarbamates on a chiral column only. Cleavage of the carbamate could not be effected. CD-Spectra of (1"S, 1"S)- and (1"R, 1"R)-dicarbamates of geometrical isomers of (3R, 3'R)- and (3R, 3'S)-meso-zeaxanthin were systematically studied and the contribution from the carbamate moieties revealed. It was concluded that (9Z, 3R, 3'S)-"meso"-zeaxanthin, in spite of having no symmetry elements, is optically inactive. The result has been rationalised in line with the current hypothesis on the origin of carotenoid CD spectra.

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Chromatography, High Pressure LiquidCircular DichroismStereoisomerismXanthophyllsZeaxanthinsbeta CaroteneJournal ArticleResearch Support, Non-U.S. Gov't

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B F Lutnaes, O R Gautun, S Liaaen-Jensen. 2001-05-05. Is (9Z)-"meso"-zeaxanthin optically active?. https://doi.org/10.1002/chir.1023

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