title: Stoichiometric C6-oxidation of hyaluronic acid by oxoammonium salt TEMPO⁺Cl⁻ in an aqueous alkaline medium.
abstract: This paper reports the selective oxidation of hyaluronic acid (HA) by stoichiometric quantity of 2,2,6,6-tetramethylpiperidine-1-oxoammonium chloride (TEMPO(+)) in aqueous alkaline medium. High efficiency of the HA oxidation and quantitative yield of carboxy-HA per starting TEMPO(+), as well as unusual behavior of the oxidation system generating an oxygen upon alkali-induced oxoammonium chloride decomposition are demonstrated. The scheme for HA oxidation involving both TEMPO(+) and oxygen produced upon the TEMPO(+)Cl(-) decomposition and/or air oxygen is proposed. For comparison, the data on stoichiometric oxidation of such substrates as dermatan sulfate, water-soluble potato starch, methyl 2-acetamido-2-deoxy-β-d-glucopyranoside and ethanol are presented.
authors.affiliation: Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa 450075, Russian Federation. Electronic address: ponedelkina@rambler.ru.
authors.forename: Irina Yu
authors.initials: IY
authors.lastname: Ponedel'kina
authors.affiliation: Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa 450075, Russian Federation.
authors.forename: Elvira A
authors.initials: EA
authors.lastname: Khaibrakhmanova
authors.affiliation: Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa 450075, Russian Federation.
authors.forename: Tatyana V
authors.initials: TV
authors.lastname: Tyumkina
authors.affiliation: Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa 450075, Russian Federation.
authors.forename: Irina V
authors.initials: IV
authors.lastname: Romadova
authors.affiliation: Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa 450075, Russian Federation.
authors.forename: Victor N
authors.initials: VN
authors.lastname: Odinokov
keywords: 2,2,6,6-Tetramethylpiperidine-1-oxoammonium chloride; 2,2,6,6-Tetramethylpiperidine-1-oxyl (CID 2724126); Hyaluronic acid; Hyaluronic acid (CID 3084049); Hydroxylamine TEMPOH; Oxidation; Radical TEMPO