title: Synthesis and NMR characterization of (Z,Z,Z,Z,E,E,ω)-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),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 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),ω)-heptaprenol 4 in gram quantities will enable preparative access to key reagents for the study of the biosynthesis of the bacterial cell envelope.
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Dusan
authors.initials: D
authors.lastname: Hesek
authors.forename: Mijoon
authors.initials: M
authors.lastname: Lee
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Zajíček
authors.forename: Jed F
authors.initials: JF
authors.lastname: Fisher
authors.forename: Shahriar
authors.initials: S
authors.lastname: Mobashery
mesh_terms: D045782:Hemiterpenes; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D000439:Pentanols / Q000138:chemical synthesis* / Q000737:chemistry; D013450:Sulfones / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D045782:Hemiterpenes; D000439:Pentanols; D013450:Sulfones; C009034:prenol