Method for purifying .alpha.- L-aspartyl-L-phenylalanine lower alkyl ester
AssigneesSagami Chemical Research Center, Ajinomoto Co., Inc., Toyo Soda Mfg. Co.
InventorsMasashige Kubo, Yuji Nonaka, Keiichi Kihara
Life of this patent
Estimating the term…
Abstract
A method for purifying an .alpha.-L-aspartyl-L- phenylalanine lower alkyl ester containing impurities. The .alpha.-L-aspartyl-L-phenylalanine lower alkyl ester is brought into contact with a Cl-type anion exchange resin in an aqueous medium to have the impurities adsorbed by the anion exchange resin. The impurities contained in the .alpha.-L-aspartyl-L-phenylalanine lower ester, particularly diketopiperazine and .alpha.-L-aspartyl-L-phenylalanine are selectively and easily removed. The desired matter thus can be easily recovered and disposal of waste liquid, etc. can also be carried out without difficulty.
Claims4
A method for purifying an .alpha.-L-aspartyl-L-phenylalanine lower alkyl ester containing impurities including .alpha.-L-aspartyl-L-phenylalanine and 3-benzyl-6-carboxymethyl-2,5-diketopiperazine, and which comprises contacting the .alpha.-L-aspartyl-L-phenylalanine lower alkyl ester with a Cl-type anion exchange resin in an aqueous solvent, thereby adsorbing the impurities in the anion exchange resin and recovering the .alpha.-L-aspartyl-L-phenylalanine lower alkyl ester in a purified state.
Dependencies are inferred from the claim text.