| 摘要 |
PURPOSE:To obtain beta-hydroxyamino acid in high yield, without side reactions, and high steric selectivity, by the reaction of a moderately reactive alpha-isocyanoacetic acid dialkylamide with an aldehyde or a ketone, followed by hydrolysis. CONSTITUTION:alpha-Isocyanoacetic acid dialklamide of formula I (R<3>, R<4>=alkyl) obtained by the reaction of alpha-isocyanoacetic acid ester with dialkylamine, e.g. alpha-isocyanoacetic acid dimethylamide, is made to react with an aldehyde or a ketone of formula II (R<1>=H, COOH, alkyl, etc,; R<2>=H, alkyl) in the presence of a base, e.g. NaOH, to prepare 5-substituted or unsubstituted-2-oxazoline-4-carboxylic acid dialkylamide. The compound obtained is hydrolyzed to prepare beta-hydroxyamino acid of formula IV. |
