| 摘要 |
NEW MATERIAL:3-Methoxy-4-hydroxy-4-methoxycarbonyl-5-methoxycyclopenta none of formula I. USE:Synthetic intermediate for perfumery and pharmaceutical. PREPARATION:The compound of formula I is produced by reacting a 4,5- monounsaturated pyranuroic acid triacetate methyl ester with methyl alcohol in the presence of a base (e.g. triethylamine) at -10-100 deg.C, preferably 0-40 deg.C for 5-30hr. The amount of the base is 2-20mol., preferably 3-5mol. per 1mol. of the compound of formula II. The compound of formula II can be produced by treating alpha-D-galactopyranuroic acid with acetic anhydride-4-dimethylami nopyridine system and esterifying the reaction product by conventional method.
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