title: Efficient chemical synthesis of both anomers of ADP L-glycero- and D-glycero-D-manno-heptopyranose.
abstract: A series of anomeric phosphates and ADP-activated L-glycero- and D-glycero-D-manno-heptopyranoses has been prepared in high overall yields, which provided model compounds and substrates in the elucidation of biosynthetic pathways and glycosyl transfer reactions of nucleotide-activated bacterial heptoses. The alpha-anomers of the heptosyl phosphates were obtained in high yield and selectivity using the phosphoramidite procedure, whereas the beta-phosphates were formed preferentially employing acylation of reducing heptoses with diphenyl phosphorochloridate. An efficient route to the formation of the nucleotide diphosphate sugars was elaborated by coupling of the O-acetylated phosphates with AMP-morpholidate followed by alkaline deprotection to furnish ADP-L- and D-glycero-alpha-D-manno-heptose in 84 and 89% yield, respectively. Deacetylation of the O-acetylated beta-configured ADP heptoses was conducted at strictly controlled conditions (-28 degrees C at pH 10.5) to suppress formation of cyclic heptose-1,2-phosphodiesters with concomitant release of AMP. Isolation of the unstable beta-configured ADP-heptoses by anion-exchange chromatography and gel-filtration afforded ADP L- and D-glycero-beta-D-manno-heptose in high yields.
authors.affiliation: Institute of Chemistry, University of Agricultural Sciences, Muthgasse 18, A-1190 Vienna, Austria.
authors.forename: Alla
authors.initials: A
authors.lastname: Zamyatina
authors.forename: Sabine
authors.initials: S
authors.lastname: Gronow
authors.forename: Michael
authors.initials: M
authors.lastname: Puchberger
authors.forename: Andrea
authors.initials: A
authors.lastname: Graziani
authors.forename: Andreas
authors.initials: A
authors.lastname: Hofinger
authors.forename: Paul
authors.initials: P
authors.lastname: Kosma
mesh_terms: D000107:Acetylation; D000244:Adenosine Diphosphate / Q000737:chemistry*; D000249:Adenosine Monophosphate / Q000737:chemistry; D002240:Carbohydrate Sequence; D002241:Carbohydrates / Q000737:chemistry; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D011756:Diphosphates / Q000737:chemistry; D006539:Heptoses / Q000138:chemical synthesis* / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008070:Lipopolysaccharides / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010710:Phosphates / Q000737:chemistry; D013696:Temperature
chemical_list: D002241:Carbohydrates; D011756:Diphosphates; D006539:Heptoses; D008070:Lipopolysaccharides; D010710:Phosphates; C062615:glycero-alpha-manno-heptopyranose; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate