| 摘要 |
(4S)-6-fluoro-spiro-[chroman-4,4'-imidazolidin -2',5'-dione is prepd. Thus, 13ml methane sulfonic acid is added to the mixt. contg. 4.35g 4-(2'-bromoethoxy) fluorobenzene and 4.7g N-acetylalpha- hydroxyglycine with stirring. The reaction mixt. produced is stirred at 20≦̸C for 18hr to give 3.8g N-acetyl-2-(2'-bromoethoxy)-5- fluorophenylglycine (m.p.=170-178≦̸C, yield=56%). |
