Synthesis of allyl O-[sodium(alpha-D-glycero-D-talo-2- octulopyranosyl)onate]-(2-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosi de, a core constituent of the lipopolysaccharide from Acinetobacter calcoaceticus NCTC 10305.
Reaction of methyl 2,6-anhydro-2,3-dideoxy-D-manno-2-octenoate 1 with 3-chloroperoxybenzoic acid gave the 2,3-anhydro derivative 2, which was converted into the per-O-acetylated anomeric methyl glycosides of D-glycero-D-galacto-2-octulopyranosylonic acid in good yield. Subsequent inversion of the configuration at C-3 and deprotection afforded sodium (methyl beta-D-glycero-D-talo-2-octulopyranosid)onate. Alternatively, 2 was transformed into methyl (alpha-D-glycero-D-talo-2- octulopyranosyl bromide(onate derivatives. Reaction with methanol or allyl 2-acetamido-2-deoxy- 3,4-O-(1,1,3,3-tetraisopropyldisiloxan-1,3-diyl)-beta-D-g lycopyranoside, promoted by silver triflate, gave good yields of the corresponding orthoester derivatives. Me3Si triflate-catalyzed orthoester rearrangement and removal of the protecting groups afforded sodium O-(methyl alpha-D-glycero- D-talo-2-octulopyranosid)onate and the disacchanide, allyl O-[sodium(alpha-D-glycero-D-talo-2- octulopyranosyl)onate]-(2-->6)-2-acetamido-2-deoxy-beta-D-gl ucopyranoside in high yield.
Gass
J
J
Institut für Chemie, Universität für Bodenkultur, Wien, Austria.
Strobl
M
M
Loibner
A
A
Kosma
P
P
Zähringer
U
U
D016954:Acinetobacter calcoaceticus / Q000737:chemistry*; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D008070:Lipopolysaccharides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009904:Optical Rotation
D004187:Disaccharides; D007202:Indicators and Reagents; D008070:Lipopolysaccharides; C082428:allyl O-(glyero-talo-2-octulopyranosy)onate-(2-6)-2-acetamido-2-deoxyglucopyranoside