title: Structural characterization and antimicrobial evaluation of atractyloside, atractyligenin, and 15-didehydroatractyligenin methyl ester.
abstract: We report the first complete structure elucidation of the ent-kaurane diterpenoid glycoside atractyloside (1) by means of NMR and X-ray diffractometry techniques. Extensive one- and two-dimensional NMR experiments were employed to assign the proton and carbon signals of 1, and crystallography experiments established the configurations of all stereogenic centers. Furthermore, we present a novel semisynthetic route for the preparation of the highly cytotoxic aglycone derivative of 1, 15-didehydroatractyligenin methyl ester (3). All compounds were tested for their antibiotic activity against Enterococcus faecalis, Escherichia coli, and several strains of Staphylococcus aureus, including fluoroquinolone-resistant (SA1199B) and two epidemic MRSA (EMRSA-15 and -16) strains. Compound 3 exhibited moderate activity against all of the Staph. aureus strains with an MIC value of 128 mg/L.
authors.affiliation: UCL School of Pharmacy, London, WC1N 1AX, UK. brucoli@pharmacy.ac.uk
authors.forename: Federico
authors.initials: F
authors.lastname: Brucoli
authors.forename: Maria T
authors.initials: MT
authors.lastname: Borrello
authors.forename: Paul
authors.initials: P
authors.lastname: Stapleton
authors.forename: Gary N
authors.initials: GN
authors.lastname: Parkinson
authors.forename: Simon
authors.initials: S
authors.lastname: Gibbons
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D001278:Atractyloside / Q000031:analogs & derivatives / Q000737:chemistry* / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D013293:Enterococcus faecalis / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D019906:Nuclear Magnetic Resonance, Biomolecular; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: C574828:15-didehydroatractyligenin methyl ester; D000900:Anti-Bacterial Agents; C462123:atractyligenine; D001278:Atractyloside