2‐Oxy‐galaktal und die Darstellung der Kojisäure (2‐Oxymethyl‐5‐oxy‐γ‐pyron) aus Galaktose

Sugar enolones: synthesis, reactions of preparative interest, and γ-pyrone formation

“…6) formulated a hexose-3,2-enolone to mechanistically rationalise the conversion of Maurer's "tetra-acetyl glucosone hydrate" into diacetylkojic acid (Refs. 7,8), and Lemieux and Wolfrom (Ref. 9) postulated a 3,4-enolone intermediate of type II to account for the ready formation of maltel from the streptose portion of Streptomycin on treatment with alkali.…”

Chemo-enzymatic three-step conversion of glucose to kojic acid

“…Chemically, kojic acid has been prepared from tetraacetylgalactosone hydrate under acetylating conditions with pyridine and acetic anhydride to yield diacetylkojic acid, followed by deacetylation with ammonia in methanol. 30 Preparation of acylated kojic acids has been reported previously also, for example, by oxidation of C2 in tetra-1,3,4,6-O-acetyl-Dgalactose and the corresponding glucose analogue; 31 dibenzoylkojic acid has been prepared from the glucosone derivative 1-chloro-3,5-dibenzoyl-glucoson-4,5-ene by boiling the starting material in acetic acid and sodium acetate. 32 For broader use and supply, the development of efficient chemical synthesis of kojic acid would be desirable.…”