| 摘要 |
PURPOSE:To efficiently obtain the subject compound for intermediate of drug, pesticide or optically active polymer, by using 5-substituted hydantoin of racemic modification derived from aldehydes in low cost as a raw material and diazotizing D-alpha-ureidocarboxylic acid obtained from said 5-substituted hydantoin. CONSTITUTION:A D-alpha-ureidocarboxylic acid (e.g., D-alpha-ureidopropionic acid) expressed by formula I [R1, R2 is H, (substituted) alkyl, (substituted) aryl; *shows stereospecific configuration of (R) to asymmetric carbon atom] is subjected to diazotization treatment in acidic aqueous solution of mineral acid and in the presence of halogenic ion (preferably halogenized alkali metal salt is previously added and furthermore diazotized using nitrous acid alkali metal salt of >=2 equiv. to D-alpha-ureidocarboxylic acid) to obtain D-alpha-halogenocarboxylic acid (e.g., D-alpha-chloropropionic acid) expressed by formula II (X is Cl or Br). The compound expressed by formula I is obtained from the compound expressed by formula III. |
