| 摘要 |
PURPOSE:To prepare the titled substance useful as a remedy for uremia and renal insufficiency, or a synthetic intermediate of amino acid, etc., by the thermal hydrolysis of a hydantoin derivative in the presence of a tertiary amine. CONSTITUTION:The tertiary amine salt of the compound of formula II (R1 is lower alkyl, 2-carboxyethyle, methylthiomethyl or 3-indolylmethyl) can be prepared by hydrolyzing the compound of formula I (R2 is lower alkylidene, 2-carboxyethylidene, methylthiomethylidene or 3-indolylmethylidene) in the presence of a tertiary amine (e.g. triethylamine) at 120-150 deg.C. The amount of the tertiary amine is 5-10 moles per 1mol of the compound of formula I . EFFECT:The free tertiary amine which has lower boiling point than water or forms an azeotropic mixture with water can be recovered easily by using water or an aqueous medium as the reaction solvent. |
