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Synthesis and NMR characterization of (Z,Z,Z,Z,E,E,?)-heptaprenol.

ABSTRACT: We describe a practical, multigram synthesis of (2Z,6Z,10Z,14Z,18E,22E)-3,7,11,15,19,23,27-heptamethyl-2,6,10,14,18,22,26-octacosaheptaen-1-ol [(Z(4),E(2),?)-heptaprenol, 4] using the nerol-derived sulfone 8 as the key intermediate. Sulfone 8 is prepared by the literature route and is converted in five additional steps (18% yield from 8) to (Z(4),E(2),?)-heptaprenol 4. The use of Eu(hfc)(3) as an NMR shift reagent not only enabled confirmation of the structure and stereochemistry of 4, but further enabled the structural assignment to a major side product from a failed synthetic connection. The availability by this synthesis of (Z(4),E(2),?)-heptaprenol 4 in gram quantities will enable preparative access to key reagents for the study of the biosynthesis of the bacterial cell envelope.

SUBMITTER: Hesek D

PROVIDER: S-EPMC3469273 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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Synthesis and NMR characterization of (Z,Z,Z,Z,E,E,ω)-heptaprenol.

Hesek Dusan D Lee Mijoon M Zajíček Jaroslav J Fisher Jed F JF Mobashery Shahriar S

Journal of the American Chemical Society 20120810 33

We describe a practical, multigram synthesis of (2Z,6Z,10Z,14Z,18E,22E)-3,7,11,15,19,23,27-heptamethyl-2,6,10,14,18,22,26-octacosaheptaen-1-ol [(Z(4),E(2),ω)-heptaprenol, 4] using the nerol-derived sulfone 8 as the key intermediate. Sulfone 8 is prepared by the literature route and is converted in five additional steps (18% yield from 8) to (Z(4),E(2),ω)-heptaprenol 4. The use of Eu(hfc)(3) as an NMR shift reagent not only enabled confirmation of the structure and stereochemistry of 4, but furth ...[more]

PMID: 22861066

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