title: alpha,beta-Dibenzyl-gamma-butyrolactone lignan alcohols: total synthesis of (+/-)-7'-hydroxyenterolactone, (+/-)-7'-hydroxymatairesinol and (+/-)-8-hydroxyenterolactone.
abstract: Two trans-alpha,beta-dibenzyl-gamma-butyrolactone lignans carrying a hydroxyl group at the beta-benzylic carbon atom and a alpha-hydroxy alpha,beta-dibenzyl-gamma-butyrolactone lignan were synthesized in racemic form using the tandem conjugate addition reaction to construct the basic lignan skeleton. Subsequent reaction steps involved either a catalytic reduction of the regenerated keto group to the alcohol, or a hydrogenolysis to benzylic methylene followed by lactone enolate formation and oxidation to give the alpha-hydroxybutyrolactones. These procedures were applied for the synthesis of 7'-hydroxyenterolactones and 7'-hydroxymatairesinols, and 8-hydroxyenterolactones, respectively. The diastereomeric mixtures of these compounds were separated either by HPLC techniques or column chromatography and the structures were elucidated using NMR spectroscopy.
authors.affiliation: Organic Chemistry Laboratory, Department of Chemistry, P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 University of Helsinki, Finland. taru.makela@helsinki.fi
authors.forename: T H
authors.initials: TH
authors.lastname: Mäkelä
authors.forename: S A
authors.initials: SA
authors.lastname: Kaltia
authors.forename: K T
authors.initials: KT
authors.lastname: Wähälä
authors.forename: T A
authors.initials: TA
authors.lastname: Hase
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D000972:Antineoplastic Agents, Phytogenic / Q000138:chemical synthesis / Q000737:chemistry; D002845:Chromatography; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D017705:Lignans / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry*; D013237:Stereoisomerism; D014197:Trees / Q000737:chemistry
chemical_list: D000438:Alcohols; D000972:Antineoplastic Agents, Phytogenic; D007783:Lactones; D017705:Lignans; D010936:Plant Extracts; C419306:hydroxymatairesinol