| 摘要 |
PURPOSE: To obtain a new compound improved in preservation stability without impairing the physiological, pharmacological and antioxidative activities, etc., of the ascorbic acid, thus applicable to medicines, cosmetics, foods, etc. CONSTITUTION: This compound, 2-O-(2'-oxymethyl-5'-hydroxy-γ-pyrone)-L-ascorbic acid, is expressed by formula I. This compound is obtained by reaction between a kojic acid derivative of formula II(R1 is benzyl, methoxymethyl, etc.; X is Cl, Br, etc.) such as 2-chloromethyl-5-benzyloxy-γ-pyrone and an ascorbic acid derivative of formula III (R2 is methylene, ethylidene, etc.; R1 is benzyl, t-butyl, etc.) such as 3-O-benzyl-5,6-O-isopropylidene-L-ascorbic acid in the presence of a basic catalyst (pref. dimethylaminopyridine, etc.), followed by elimination of the R1 to R3 groups in the resultant product under acidic or reductive conditions. |
