公开(公告)号：AU590439B2

公开(公告)日：1989-11-02

申请号：AU7681987

申请日：1987-08-12

Applicant: TOSOH CORP

Inventor： WAKAMATSU HIDETOSHI ,  IRINO SHIGEAKI ,  HARADA TSUNEO ,  OYAMA KIYOTAKA ,  TOKUDA AKIRA

IPC: A23L27/30 ,  C07K1/14 ,  C07K5/072 ,  C07K5/075 ,  C07K5/06

Abstract: A process for producing dry alpha -L-aspartyl-L-phenylalanine methyl ester having an improved solubility by drying wet crystals of alpha -L-aspartyl-L-phenylalanine methyl ester, characterized in that the wet crystals of alpha -L-aspartyl-L-phenylalanine methyl ester are granulated so that the specific surface area during the drying operation is at least 4 m /g, followed by drying.

公开(公告)号：JPH10101633A

公开(公告)日：1998-04-21

申请号：JP25615596

申请日：1996-09-27

Applicant: TOSOH CORP

Inventor： KATSUURA KIMIO ,  IRINO SHIGEAKI ,  TOKUDA AKIRA

IPC: C07C231/20 ,  C07C237/12 ,  C07K1/14

Abstract: PROBLEM TO BE SOLVED: To provide a method for effectively producing an optically active amino acid ester having a high optical purity and useful as a raw material for a medicine in high yield by treating a D-isomer of a specific ester additive of an amino acid in a specified condition. SOLUTION: This method for producing an optically active amino acid ester having a high optical purity comprises a step for obtaining a D-isomer of an amino acid additive of a compound of the formula by mixing and reacting an optically active amino acid ester such as (homo) phenylalanine and phenylglycine containing the D- isomer with a N-substituted-α-Laspartyl-L-phenylalanine alkyl ester of the formula [R1 is a (substituted) phenyl; R2 is an aliphatic oxycarbonyl or a (substituted) benzyloxycarbonyl; R3 is an alkyl] in an aqueous solution to provide an adduct of the D-isomer of the amino acid ester with the compound of the formula, (i) a step for separating the adduct from the aqueous phase by using a water-incompatible solvent and extracting the adduct, (ii) a step for purifying the separated adduct by washing an organic solvent layer containing the adduct as the slurry, (iii) a step for recovering the D-amino acid ester having high optical purity as an acidic solution by performing acidolysis of the adduct with an acid aqueous solution to provide the objective optically active amino acidester.

公开(公告)号：JPS6344593A

公开(公告)日：1988-02-25

申请号：JP18775886

申请日：1986-08-12

Applicant: TOSOH CORP

Inventor： WAKAMATSU HIDETOSHI ,  IRINO SHIGEAKI ,  HARADA TSUNEO ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: A23L27/30 ,  C07K1/14 ,  C07K5/06 ,  C07K5/075

Abstract: PURPOSE:To readily obtain the titled compound, having improved solubility since type II crystals are hardly contained and useful as sweeteners at a low cost, by drying alpha-L-aspartyl-L-phenylalanine methyl ester under specific condition. CONSTITUTION:Wet crystals of alpha-L-aspartyl-L-phenylalanine methyl ester are dried using dry air at

公开(公告)号：JPS6345298A

公开(公告)日：1988-02-26

申请号：JP18866386

申请日：1986-08-13

Applicant: TOSOH CORP

Inventor： WAKAMATSU HIDETOSHI ,  IRINO SHIGEAKI ,  HARADA TSUNEO ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: A23L27/30 ,  C07K1/14 ,  C07K5/06 ,  C07K5/075

Abstract: PURPOSE:To obtain type-II crystal of alpha-L-aspartyl-L-phenylalanine methyl ester having excellent storage stability without using high-temperature drying, by contacting alpha-L-aspartyl-L-phenylalanine methyl ester containing type-I crystal with a polar organic solvent. CONSTITUTION:alpha-L-aspartyl-L-phenylalanine methyl ester containing type-I crystal (having high hygroscopicity and liable to cause discoloration and decomposition during storage) can be easily converted to stable type-II crystal, by contacting the compound with a polar organic solvent (preferably 1-4C alcohol).

公开(公告)号：JPS6345296A

公开(公告)日：1988-02-26

申请号：JP18866186

申请日：1986-08-13

Applicant: TOSOH CORP

Inventor： WAKAMATSU HIDETOSHI ,  IRINO SHIGEAKI ,  HARADA TSUNEO ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: A23L27/30 ,  C07K1/14 ,  C07K5/072 ,  C07K5/075

Abstract: PURPOSE:To obtain an aspartame having excellent storage stability without using high-temperature drying process, by heat-treating an alpha-L-aspartyl-L- phenylalanine methyl ester crystal having a specific water content under a specific condition. CONSTITUTION:Stable alpha-L-aspartyl-L-phenylalanine methyl ester can be produced by heat-treating an alpha-L-aspartyl-L-phenylalanine methyl ester crystal containing 5-15% water (based on wet crystal) at 50-80 deg.C for >=30min, preferably 30 min-48hr. When the above crystal is granule produced by granulator, the diameter of the granule is preferably 0.1-10.0mm.

公开(公告)号：JPS6333396A

公开(公告)日：1988-02-13

申请号：JP17556886

申请日：1986-07-28

Applicant: TOSOH CORP

Inventor： WAKAMATSU HIDETOSHI ,  IRINO SHIGETETSU ,  HARADA TSUNEO ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: A23L27/30 ,  C07K1/00 ,  C07K5/072 ,  C07K5/075

Abstract: PURPOSE:To industrially and advantageously obtain the titled compound useful as a sweetener, etc., having improved solubility, by passing wet crystals of alpha-L-aspartyl-L-phenylalanine methyl ester through a region of specific water content at a specific temperature under normal pressure for drying. CONSTITUTION:Wet crystals of alpha-L-aspartyl-L-phenylalanine methyl ester (Aspartame) are subjected to solid-liquid separation with a centrifugal separator, passed through a screen, and granulated with a granulation machine. Then the granules are passed through a region of 5-15% based on the weight of wet crystals of alpha-L-aspartyl-L-phenylalanina methyl ester, water content at

公开(公告)号：JPH01111894A

公开(公告)日：1989-04-28

申请号：JP26804987

申请日：1987-10-26

Applicant: TOSOH CORP

Inventor： HARADA TSUNEO ,  FUKUDA KENICHI ,  SHIMIZU HIROSHI ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: C07K1/14 ,  C07K1/24 ,  C07K5/06 ,  C07K5/072 ,  C07K5/075 ,  C25B3/00 ,  C25B9/00 ,  C25B9/08 ,  C25D3/00

Abstract: PURPOSE:To efficiently remove org. acids with an anion-exchange membrane by supplying an aq. soln. of dipeptide ester(APM) contg. the org. acids into the intermediate chamber of an electrolytic cell, and electrolytically purifying the APM. CONSTITUTION:An aq. alpha-APM soln. contg. org. acids is supplied into the central section 7 of the electrolytic cell enclosed with an anion-exchange membrane 3 and a cation-exchange membrane 2 or plural anion-exchange membranes. When electrolysis is started, gaseous H2 is generated from a cathode 4, and gaseous chlorine is generated from an anode 5. The anions of the 1,3-benzyl-6- carboxymethyl-2,5-diketopiperazine(DKP), alpha-L-aspartyl-L-phenylalanine(AP), etc., are moved to an anode chamber 8 from the intermediate chamber 7, or the central chamber 7, through the anion-exchange membrane 3. The cations are moved to a cathode chamber 6. As a result, the inorg. ion and org. ion are efficiently removed.

公开(公告)号：JPS6463565A

公开(公告)日：1989-03-09

申请号：JP22049987

申请日：1987-09-04

Applicant: TOSOH CORP

Inventor： HARADA TSUNEO ,  TOKUDA AKIRA ,  KOYAMA KIYOTAKA

IPC: C07C271/54 ,  C07C67/00 ,  C07C239/00 ,  C07C269/04 ,  C07C271/22

Abstract: PURPOSE:To obtain the title compound of reduced impurities from benzyl chloroformate and L-aspartic acid, by allowing the title compound or its salt to exist beforehand in the reaction system at the start to facilitate the control of the reaction. CONSTITUTION:When N-benzyloxycarbonyl-L-aspartic acid (Z-Asp) is prepared from benzyl chloroformate (Z-Cl) and L-aspartic acid (Asp), Z-Asp or its salt is allowed to exist beforehand in the reaction system at the start of the reaction in an amount of 0.5-50mol.% based on L-Asp, and the reaction mixture is kept at 0-60 deg.C, 9.5-13.5pH to facilitate the reaction control to give Z-Asp of reduced impurities, which is used as a starting substance of alpha-L-aspartyl-L- phenylalanine methyl ester (artificial sweetener).

公开(公告)号：JPH10101628A

公开(公告)日：1998-04-21

申请号：JP25615396

申请日：1996-09-27

Applicant: TOSOH CORP

Inventor： KATSUURA KIMIO ,  IRINO SHIGEAKI ,  TOKUDA AKIRA

IPC: C07B57/00 ,  C07C227/34 ,  C07C229/36

Abstract: PROBLEM TO BE SOLVED: To efficiently obtain an optically active amino acid (derivative) in high optical purity by previously preparing an optically active amino acid (derivative) in an optical purity not lower than a convergent value of mutual solubility between optical isomers and crystallizing an optically active amino acid (derivative) which excessively exists. SOLUTION: One or more kinds of optically active amino acids (derivatives) selected from a group of phenylglycine (derivative), phenylalanine (derivative), homophenylalanine (derivative) and naphthylalanine (derivative) are previously prepared in an optical purity not lower than a convergent value of mutual solubility between optical isomers and an optically active amino acid (derivative) which excessively exists is crystallized to provide the objective optically active amino acid (derivative) having high optical purity. Furthermore, the convergent value of mutual solubility between optical isomers indicates a ratio (optical purity in mother liquid) of target optical isomer to optical isomers in mother liquid equilibrated when crystals of racemic substance and optically active substance simultaneously exist and the value is constant without depending on a ratio of crystals of the racemic substance and the optically active substance.

公开(公告)号：JPH10101626A

公开(公告)日：1998-04-21

申请号：JP25615496

申请日：1996-09-27

Applicant: TOSOH CORP

Inventor： KATSUURA KIMIO ,  IRINO SHIGEAKI ,  TOKUDA AKIRA

IPC: C07B57/00 ,  C07B63/00 ,  C07C227/34 ,  C07C229/36

Abstract: PROBLEM TO BE SOLVED: To provide a method for producing an optically active amino acid having a high optical purity of at least >=99% or its hydrochloride. SOLUTION: In this method for producing an optically active amino acid having high optical purity or its hydrochloride by crystallization from an optically active amino acid containing an optical isomer, crystallization of an optically active substance is carried out in pH region exhibiting an isoelectric point by utilizing pH dependence of convergence of mutual solubility between optical isomers and then, pH of recovered mother liquid is lowered to