title: A method for determination of the absolute configuration of chiral glycerol residues in natural products using TEMPO oxidation and characterization of the glyceric acids formed.
abstract: A method has been developed for determination of the absolute configuration of glycerol residues in natural products. It is required that the glycerol moiety contain a primary nonsubstituted hydroxymethyl group or that such a group can be obtained by modification without racemization. The method employs TEMPO oxidation of the primary hydroxyl group, hydrolysis, butanolysis with chiral 2-butanol, and acetylation. The acetylated (+)-2-butyl esters of the glyceric acid formed by oxidation are analyzed by gas-liquid chromatography. The esterification can also be performed with other chiral alcohols, e.g., (-)-2-octanol. The method is general and applicable to both primary and secondary substituted glycerols. It has recently been used for determination of the chiral glycerol-1-phosphate residue of the Escherichia coli O28 O-antigen, and now we report the absolute configurations of the glycerol moieties in Streptococcus pneumoniae type 18A and Streptococcus agalactaie type III. All studied glycerol residues were found to have the D-configuration.
authors.affiliation: Department of Organic Chemistry, Stockholm University, Stockholm, S-106 91, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Rundlöf
authors.forename: G
authors.initials: G
authors.lastname: Widmalm
mesh_terms: D002240:Carbohydrate Sequence; D003497:Cyclic N-Oxides; D004926:Escherichia coli / Q000737:chemistry; D005988:Glyceric Acids / Q000737:chemistry; D005990:Glycerol / Q000737:chemistry*; D008070:Lipopolysaccharides / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010766:Phosphorylation; D011134:Polysaccharides / Q000737:chemistry; D013237:Stereoisomerism; D013292:Streptococcus agalactiae / Q000737:chemistry; D013296:Streptococcus pneumoniae / Q000737:chemistry; D013682:Teichoic Acids / Q000737:chemistry
chemical_list: D003497:Cyclic N-Oxides; D005988:Glyceric Acids; D008070:Lipopolysaccharides; D011134:Polysaccharides; D013682:Teichoic Acids; D005990:Glycerol; C003959:TEMPO