title: Investigation into an efficient synthesis of 2,3-dehydro-N-acetyl neuraminic acid leads to three decarboxylated sialic acid dimers.
abstract: Sialic acid, an important carbohydrate found incorporated on the cell surface of many organisms, has been modified for use in a wide range of biological and pharmaceutical applications. We hypothesized that 4,7,8,9-tetra-O-acetyl-2-deoxy-2,3-dehydro-N-acetyl neuraminic acid methyl ester (4) could be efficiently synthesized in a one-pot reaction by heating peracetylated sialic acid (2) in pyridine and acetic anhydride to induce beta-elimination. When reduced to practice, this reaction produced only modest yields of 4. Six compounds, including three new decarboxylated sialic acid dimers, were also found to have been synthesized in the reaction. In an effort to better understand the chemistry and the mechanisms of this reaction, all of the side products were isolated and fully characterized.
authors.affiliation: Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Evan J
authors.initials: EJ
authors.lastname: Horn
authors.forename: Jonel P
authors.initials: JP
authors.lastname: Saludes
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Gervay-Hague
mesh_terms: D003653:Decarboxylation; D019281:Dimerization; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008956:Models, Chemical; D015394:Molecular Structure; D019158:N-Acetylneuraminic Acid / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000737:chemistry; D009438:Neuraminic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D012794:Sialic Acids / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: C421922:4,7,8,9-tetra-O-acetyl-N-acetyl-2,3-dehydro-2-deoxy-4-neuraminic acid methyl ester; D009438:Neuraminic Acids; D012794:Sialic Acids; C036137:2-deoxy-2,3-dehydro-N-acetylneuraminic acid; D019158:N-Acetylneuraminic Acid