| 摘要 |
<p>PURPOSE:N-acetoacetylanthranylic acid ester is brought into contact with alkali metal lower-alcoholate to achieve high-yield production of the titled substance of high purity used as an intermediate of a remedy for allergic asthma. CONSTITUTION:A compound of formula I (X is 1-5C alkyl, alkoxy, 2-6C alkoxycarbonyl, halogen; n is integer of 0-4; R is lower alkyl) is subjected to reaction in the presence of an alkali metal lower alcoholate such as sodium methylate in an amount of 2-3 times the mole of the compound, preferably in a solvent such as a lower monohydric alcohol to give the compound of formula II. When methanol is used as a solvent, the reaction under reflux at its boiling point (64 deg.C) finishes in 30min.</p> |
