A process for preparing (1'R,3S)-3-(1'-hydroxyethyl)-azetidin-2-one or a derivative thereof represented by formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or a hydroxyl-protective group, is disclosed, comprising reacting (2S,3R)-2-aminomethyl-3-hydroxybutyric acid or a derivative thereof represented by formula (II): ##STR2## wherein R.sup.1 is as defined above, with a sulfenamide represented by formula (III): ##STR3## wherein R.sup.2 represents ##STR4## and R.sup.3 and R.sup.4 each represent a hydrogen atom or a cyclic or acyclic hydrocarbon group, provided that they do not simultaneously represent a hydrogen atom, or R.sup.3 and R.sup.4 are taken together with the adjacent nitrogen atom to form a heterocyclic group, and triphenylphosphine. The reaction yield is high, and the sulfenamide (III) used as a lactamization reagent is cheap and can be recovered after the reaction.
本发明揭示了一种制备(1'R,3S)-3-(1'-羟基乙基)-氮杂
环戊酮或其衍
生物的方法,其
化学式表示为(I):##STR1##其中R.sup.1代表氢原子或羟基保护基,包括将(2S,3R)-2-
氨甲基-3-羟基
丁酸或其衍
生物,其
化学式表示为(II):##STR2##其中R.sup.1如上所定义,与
化学式为(III)的磺酰胺反应,其
化学式表示为:##STR3##其中R.sup.2代表##STR4##R.sup.3和R.sup.4分别代表氢原子或环烷基或非环烷基,但不能同时表示氢原子,或R.sup.3和R.sup.4与相邻的氮原子结合形成杂环基团,同时还使用
三苯基膦。反应产率高,磺酰胺(III)作为内酰胺化试剂便宜且反应后可以回收利用。