摘要:
An industrially advantageous method of producing &bgr;-halogeno-&agr;-aminocarboxylic acids is provided. Methods are also provided of producing optically active N-protected-S-phenylcysteines having high optical purity and of intermediates thereof, respectively, in which the above production method is utilized. A method of producing &bgr;-halogeno-&agr;-aminocarboxylic acids or salts thereof is disclosed which comprises halogenating the hydroxyl group of a &bgr;-hydroxy-&agr;-aminocarboxylic acid (in which the basicity of the amino group in &agr;-position is not masked by the presence of a substituent on said amino group) or a salt thereof with an acid with a halogenating agent. A method of producing optically active N-protected-S-phenylcysteines represented by the general formula (3) or salts thereof is further disclosed which comprises applying the above production method to optically active serine or a salt thereof and then carrying out treatment with an amino-protecting agent and reaction with thiophenol under a basic condition.
摘要:
The present invention provides a production method of high quality threo-1,2-epoxy-3-amino-4-phenylbutane derivatives (1) on a commercial scale in a simple, easy and efficient manner and with very high productivity, which comprises treating a threo-1-halo-2-hydroxy-3-amino-4-phenylbutane derivative (2) with a base in a polar organic solvent or a solvent composed of a polar organic solvent and water, and adding the resulting reaction mixture to water to thereby cause the resulting threo-1,2-epoxy-3-amino-4-phenylbutane derivative (1) to crystallize out.