| 摘要 |
PURPOSE:To obtain the subject ester useful as a dietary sweetener by bringing crude alpha-L-aspartyl-L-phenylalanine methyl ester into contact with a mineral acid, etc., in an organic carboxylic acid and subsequently isolating the ester as a mineral acid salt, etc., thereof. CONSTITUTION:Crude alpha-L-aspartyl-L-phenylalanine methyl ester is brought into contact with a mineral acid (preferably sulfuric acid) or an organic sulfonic acid (preferably methane sulfonic acid) in an organic carboxylic acid (preferably acetic acid) or an organic solvent containing the organic carboxylic acid. The alpha-L-aspartyl-L-phenylalanine methyl ester is subsequently isolated as a mineral acid salt or organic sulfonic acid salt thereof. |
