Carotenoids and related compounds. Part XXX. Stereochemistry and synthesis of phytoene

Abstract

Studies on models synthesised by stereochemically controlled routes have been used to elucidate the configurations of the central triene chromophores in the phytoenes (7,8,11,12,7′,8′,11′,12′-octahydro-ψ,ψ-carotenes). The common natural phytoene has been shown to be cis about the 15,15′-double bond only, and the main phytoene from Flavobacterium dehydrogenans to be the all-trans-isomer. Both these isomers have been synthesised, and their stereomutation has been studied.