88759-60-8Relevant academic research and scientific papers
Method for preparing levorotatory oxiracetam crystal form II through pH method
-
, (2017/09/01)
The invention relates to a preparation method of a levorotatory oxiracetam crystal form II. The method comprises the steps of adopting S-4-chlorine-3-hydroxybutyrate and sodium azide as starting raw materials for preparing to obtain high-purity (S)-4-hydroxy-2 oxo-1-pyrrolidine acetamide; using acetic acid/ammonium hydroxide for preparing to obtain the (S)-4-hydroxy-2 oxo-1-pyrrolidine acetamide crystal from II through a pH method. The optical purity is 99.9 percent or above, and the product quality of the (S)-4-hydroxy-2 oxo-1-pyrrolidine acetamide crystal from II is greatly improved.
Preparation method for (S)-oxiracetam
-
, (2016/12/01)
The invention provides a preparation method for (S)-oxiracetam. The preparation method comprises the following steps: (1) with S-4-chloro-3-hydroxy butyrate as an initial raw material, subjecting the initial raw material and an azido reaction agent to an azido reaction so as to obtain an intermediate I; (2) subjecting the intermediate I to a reduction reaction so as to obtain an intermediate II; (3) subjecting the intermediate II and halogenated acetate to a condensation reaction so as to obtain an intermediate III; (4) subjecting the intermediate III to a ring closure reaction so as to obtain an intermediate IV; and (4) carrying out an aminolysis reaction on the intermediate IV so as to obtain the target product (S)-oxiracetam. The preparation method can prepare the (S)-oxiracetam product with ideal yield of at least more than 38%, and a novel synthetic route is opened up for (S)-oxiracetam.
