Processes Patents (Class 548/497)
  • Patent number: 5703106
    Abstract: The present invention provides novel compounds having pharmacological properties represented by the general formula I ##STR1## processes for the manufacture, pharmaceutical compositions and the use of the compounds of formula I and salts thereof.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: December 30, 1997
    Assignee: Japat Ltd.
    Inventors: Thomas Fruh, Thomas Pitterna, Toshiki Murata, Lene D. Svensson, Yoko Yuumoto, Junichi Sakaki
  • Patent number: 5679852
    Abstract: A process for the production of of general formula I diethylenetriaminepentacarboxylic acid monoamide derivatives ##STR1## in which E.sup.1, E.sup.2 and Z have varying meanings.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: October 21, 1997
    Assignee: Schering Aktiengesellschaft
    Inventors: Johannes Platzek, Ulrich Niedballa, Peter Mareski, Bernd Raduchel
  • Patent number: 5635379
    Abstract: Peptides containing in its amino acid chain a D-2-alkylTryptophan residue wherein the alkyl group has between one and three carbon atoms and having pharmacological activity similar to that of analogous peptides containing natural unsubstituted D-Tryptophan residues in place of the D-2-alkylTryptophan. These new peptides are more resistant to oxidative degradation which usually takes place, for example, in the presence of reactive radicals or during high energy sterilization than unsubstituted Tryptophan containing peptides. Specific peptides include His-D-2-alkyl-Trp-Ala-Trp-D-Phe-Lys-NH.sub.2, Ala-His-D-2-alkyl-Trp-Ala-Trp-D-Phe-Lys-NH.sub.2, Pyro-Glu-His-Trp-Ser-Tyr-D-2-alkyl-Trp-Leu-Arg-Pro-Gly-NH.sub.2, Pyro-Glu-His-Ser-Tyr-D-2-alkyl-Trp-Leu-Arg-Pro-NHCH.sub.2 CH.sub.3, D-Pro-Gln-Gln-D-Trp-Phe-D-Trp-2-alkyl-Trp-Met-NH.sub.2, Arg-D-Trp-N-methyl-Phe-D-2-alkyl-Trp-Leu-Met-NH.sub.2, D-Phe-Cys-Phe-D-2-alkyl-Trp-Lys-Thr-Cys-NHCH(CH.sub.2 OH)CHOHCH.sub.3 and D-Phe-Cys-Tyr-D-2-alkyl-Trp-Lys-Val-Cys-Trp-NH.sub.2.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: June 3, 1997
    Assignee: Romano Deghenghi
    Inventor: Romano Deghenghi
  • Patent number: 5622983
    Abstract: Novel unnatural dipeptoids of .alpha.-substituted Trp-Phe derivatives useful as agents in the treatment of obesity, hypersecretion of gastric acid in the gut, gastrin-dependent tumors, colorectal tumors, or as antipsychotics are disclosed. Further the compounds are antianxiety agents, antiulcer agents, antidepressant agents, and are agents useful for preventing the withdrawal response produced by chronic treatment or use followed by chronic treatment followed by withdrawal from nicotine, diazepam, alcohol, cocaine, caffeine, or opiods. Also disclosed are pharmaceutical compositions and methods of treatment using the dipeptoids as well as processes for preparing them and novel intermediates useful in their preparation. An additional feature of the invention is the use of the subject compounds to prepare pharmaceutical and diagnostic compositions.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: April 22, 1997
    Assignee: Warner-Lambert Company
    Inventors: David C. Horwell, Martyn C. Pritchard, Edward Roberts, Reginald S. Richardson, Julian Aranda
  • Patent number: 5608078
    Abstract: Dipeptide compounds and analogs thereof having a phosphonomethyl moiety are disclosed. These compounds inhibit Endothelin Converting Enzyme and are thus useful in treating conditions responsive to inhibition of production of Endothelin.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: March 4, 1997
    Assignee: Merrell Pharmaceuticals Inc.
    Inventors: Hugues d'Orchymont, Marc Bigaud
  • Patent number: 5506362
    Abstract: An .alpha.-amino acid amide is prepared by reaction of an N.sup..alpha. -aryloxycarbonylamino acid with a compound containing a free amino group. This process makes it possible readily to prepare peptides, by direct reaction between the carboxyl group of the N.sup..alpha. -aryloxycarbonyl derivative of an amino acid and the free amino group of a second amino acid or of a peptide fragment, without requiring protection of the carboxyl function of the second amino acid or of the peptide fragment, nor a coupling agent nor a deprotection step.
    Type: Grant
    Filed: June 9, 1994
    Date of Patent: April 9, 1996
    Assignee: Solvay (Societe Anonyme)
    Inventors: Roland Callens, Georges Blondeel
  • Patent number: 5329014
    Abstract: Optically active tryptophan of high purity can be obtained in high yields from a tryptophan fermentation broth, using crystallization of optically active tryptophan hydrochloride in combination with concurrent neutralization crystallization. According to the present invention, optically active tryptophan from a tryptophan containing fermentation broth, is carried out by (a) removing cells from the fermentation broth, adding hydrochloric acid, or a mixture of hydrochloric acid and an inorganic salt which contains chloride ions, to the cell-free broth to effect crystallization, (b) separating optically active tryptophan hydrochloride, (c) dissolving the optically active tryptophan hydrochloride, and (d) subjecting the resulting solution and an alkali solution to concurrent neutralization crystallization, maintaining a pH of the crystallization solution in the range of from 3 to 8.
    Type: Grant
    Filed: July 31, 1991
    Date of Patent: July 12, 1994
    Assignee: Ajinomoto Co., Inc.
    Inventors: Toru Shinohara, Masaru Otani
  • Patent number: 5300653
    Abstract: A method is provided for the separation of at least one aromatic amino acid from an aqueous solution of mixed amino acids including the aromatic amino acid. The aqueous solution is brought into contact with a strongly acidic gel-type cation exchange resin which has been converted into a salt with an alkali metal or an alkaline earth metal, whereby the aromatic amino acid is selectively sorbed by the cation exchange resin. The aromatic amino acid thus sorbed can then be desorbed from the ion exchange resin, preferably with water.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: April 5, 1994
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Shohei Nozaki, Naohiro Murata, Kiyoo Miyazaki
  • Patent number: 5283343
    Abstract: This invention relates to novel melatonin derivatives, such as 2-aryl substituted N-acetyltryptamines, having pharmacological activity, e.g., melatonin antagonist activity, and methods for the synthesis thereof.
    Type: Grant
    Filed: June 18, 1991
    Date of Patent: February 1, 1994
    Assignee: Whitby Research, Inc.
    Inventors: Margarita L. Dubocovich, Vithal J. Rajadhyaksha, James V. Peck, Atef A. Helmy
  • Patent number: 5210215
    Abstract: 3-indolepyruvic acid derivatives substituted on the benzene moiety show good antagonizing activity on excitatory aminoacids and on free radicals, for which reason they are therapeutic agents in cerebral and peripheral degenerative pathologies. Their method of production by passage through the corresponding substituted triptophane.
    Type: Grant
    Filed: September 18, 1990
    Date of Patent: May 11, 1993
    Assignee: Polifarma S.p.A.
    Inventors: Vincenzo Politi, Giovanna De Luca, Giovanni Di Stazio, Mario Materazzi
  • Patent number: 5118815
    Abstract: A method for crystallization of an amino acid characterized by allowing a surfactant and/or an alcohol to exist upon crystallization.
    Type: Grant
    Filed: October 15, 1990
    Date of Patent: June 2, 1992
    Assignee: Ajinomoto Co., Inc.
    Inventors: Yoshinari Shiroshita, Ryuta Toyomasu, Masura Saeki
  • Patent number: 5101036
    Abstract: The invention relates to a process for the preparation of N-hydroxy-alpha-amino acids and the derivatives thereof by reacting a derivative of an alpha-amino acid with an aromatic aldehyde to form a Schiff base, oxidizing the Schiff base to an oxaziridine and converting the oxaziridine into the corresponding N-hydroxy-alpha-amino acid derivative and, if so desired, converting that derivative into the acid or a different derivative, in which an alpha-amino acid amide is used as starting material.
    Type: Grant
    Filed: September 20, 1990
    Date of Patent: March 31, 1992
    Assignee: Stamicarbon B.V.
    Inventors: Johan Kamphuis, Wilhelmus H. J. Boesten
  • Patent number: 5085991
    Abstract: A process for preparing substantially purified aqueous indole solution. In the process of the present invention, crude indole containing an organic impurity is dissolved in an organic solvent which is immiscible with water, the distribution ratio of the impurity to the organic phase, when two-phase liquid system is formed with the organic solvent and an aqueous medium, being greater than that of indole; and the indole solution is contacted with water or an aqueous reaction medium for conducting the reaction to form two-phase liquid system and to distribute indole to the aqueous phase.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: February 4, 1992
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shinji Ogawa, Seiya Iguchi, Hiroshi Kimura, Hideharu Kuwamoto
  • Patent number: 5057615
    Abstract: A process for purifying tryptophan is disclosed. In the process of the present invention, tryptophan is recrystallized in water-containing acetic acid. By the process of the present invention, tryptophan with high purity may be obtained with high yield without condensation or neutralization.
    Type: Grant
    Filed: June 26, 1990
    Date of Patent: October 15, 1991
    Assignee: Mitsui Toatsu Chamicals, Inc.
    Inventors: Yoshitsugu Kono, Hiroyuki Itoh, Ryoichi Taneda, Tsugio Watanabe
  • Patent number: 4978759
    Abstract: The process described makes it possible to obtain optically pure 4-amino-3-hydroxycarboxylic acids by means of a series of stereoselective steps. The starting material is an alpha-amino acid in the L or D configuration, with which Meldrum's acid is reacted. The resulting pyrrolone derivative is reduced prior to opening of the pyrrolidine ring. The invention also relates to the new products obtained by the said process and to the pyrrolone derivatives obtained as intermediates.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: December 18, 1990
    Assignee: Sanofi, S.A. and Institut National de la Sante et de la Recherche Medicale
    Inventors: Patrick Jouin, Dino Nisato, Bertrand Castro
  • Patent number: 4912228
    Abstract: An improvement in the process of extraction of amino acids from aqueous solutions in which the amino acids are extracted with quaternary ammonium extractants. A pretreatment of the amino acid containing aqueous solution with a tertiary amine prior to extraction of the amino acids with the quaternary ammonium extractant, removes some impurities or poisons present therein, leaving the amino acids in the aqueous solution for subsequent extraction with a water insoluble quaternary ammonium extractant. After extraction with the quaternary extractant, the organic phase is stripped of amino acid and the stripped organic is subjected to an acidic scrub before returning to the quaternary extraction stage.
    Type: Grant
    Filed: August 4, 1988
    Date of Patent: March 27, 1990
    Assignee: Henkel Research Corporation
    Inventors: Thomas J. Stierman, Phillip L. Mattison
  • Patent number: 4886888
    Abstract: Amino acids can be purpified and/or concentrated by extracting aqueous mixtures such as fermentation broths by contacting an aqueous mixture containing amino acids with an organic solution containing a water insoluble extractant selected from the group consisting of:1. A quaternary ammonium ion having the formula: ##STR1## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are aliphatic, each having from 1 to 22 carbon atoms, and together have a minimum of 25 carbon atoms, and where at least three of the four R groups are at least a C.sub.4.2. A quaternary phosphonium ion having the formula: ##STR2## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are as defined above. 3. A tertiary sulfonium ion having the formula: ##STR3## where R.sub.1, R.sub.2 and R.sub.3 each are aliphatic with from 1 to 22 carbon atoms, and together have a minimum of 24 carbons and where at least two of these groups are at least a C.sub.6.4. An organic boride ion having the formula: ##STR4## where R.sub.1, R.sub.2, R.sub.3 and R.sub.
    Type: Grant
    Filed: December 22, 1986
    Date of Patent: December 12, 1989
    Assignee: Henkel Corporation
    Inventors: Francis W. Tuominen, Ronald R. Swanson, Phillip L. Mattison, Kenneth D. MacKay, Bradley W. Glorvigen
  • Patent number: 4886889
    Abstract: Disclosed is a process for recovery of amino acids from aqueous mixtures. In particular, it relates to a treatment of said amino acid containing aqueous mixture prior to extraction of the amino acid with a water immiscible organic solution containing a water insoluble extractant for said amino acid. The overall process of the invention which includes the pretreatment and extraction, also includes optional methods of recovering said extracted amino acid from the water immiscible organic solution. Accordingly, the invention also relates to a process for recovery of the amino acid by stripping of the amino acid from the organic solution and precipitation of the amino acid.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: December 12, 1989
    Assignee: Henkel Corporation
    Inventors: Phillip L. Mattison, Ronald P. Wirth, Michael J. Virnig, LeRoy Krbechek
  • Patent number: 4837371
    Abstract: An aqueous solution containing amino acids of which the solubility in water at isoelectric point is low, can be highly concentrated by means of semipermeable membranes in the presence of a water-soluble organic solvent while increasing the solubility by adjusting a pH.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: June 6, 1989
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shinji Ogawa, Seiya Iguchi, Hiroshi Kimura, Yoh Ohmori
  • Patent number: 4837332
    Abstract: Amino acid salt having at least one unblocked amino group and comprising at least one cation which has a nitrogen cationic atom is reacted with 1-(tertiary-alkoxycarbonyl)imidazole in the liquid phase and in the presence of essentially inert organic solvent having a dielectric constant at 25.degree. C. of at least about 4, to produce N-(tertiary-alkoxycarbonyl)-blocked amino acid salt.
    Type: Grant
    Filed: March 7, 1986
    Date of Patent: June 6, 1989
    Assignee: PPG Industries, Inc.
    Inventor: Chih-Yueh Chou
  • Patent number: 4822890
    Abstract: A method for the production of substantially 100% pure N.alpha.-urethane protected amino acids is disclosed. This method eliminates the formation of di-peptide and tri-peptide contaminants. Reaction of blocking reagents at the carboxylate site on a protected peptide is prevented by the application of labile amino acid esters. Subsequent removal of the ester yields, in ultra-high purity, the N.alpha.-protected amino acid. The substantially 100% pure N.alpha.-urethane protected amino acid are also disclosed.
    Type: Grant
    Filed: June 24, 1986
    Date of Patent: April 18, 1989
    Assignee: Hoffmann-La Roche Inc.
    Inventor: David R. Bolin
  • Patent number: 4808728
    Abstract: Tryptophan and esters thereof, and other indoleaminoacids, can be easily transformed into respective alpha-ketoacids through a coupling reaction with aromatic aldehydes, in the presence of a dehydrating agent.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: February 28, 1989
    Assignee: Polifarma S.p.A.
    Inventors: Giovanna De Luca, Giovanni Di Stazio, Andrea Margonelli, Mario Materazzi, Vincenzo Politi
  • Patent number: 4803284
    Abstract: The compound characterized by the structural Formula I: ##STR1## is therapeutically useful as an anti-hypertensive agent. A process for the preparation of the compound having Formula I and their synthetic intermediates is described. One of the synthetic intermediates is the compound characterized by the structural Formula: ##STR2## which is also therapeutically useful as an anti-hypertensive agent.
    Type: Grant
    Filed: August 19, 1987
    Date of Patent: February 7, 1989
    Assignee: Centro de Investigacion y de Estudios Avanzados Del Instituto Politecnico Nacional
    Inventors: Pedro Joseph-Nathan, Martha S. Morales-Rios
  • Patent number: 4778808
    Abstract: A feed additive produced by concentrating an aqueous solution containing tryptophan and impurities both originating in the culture broth of a tryptophan-producing microorganism, with the pH of the aqueous solution being maintained in the range of 4 to 6 and the temperature thereof being maintained in the range of 20.degree. to 80.degree. C. during the process of concentrating.
    Type: Grant
    Filed: March 12, 1986
    Date of Patent: October 18, 1988
    Assignee: Ajinomoto Co., Inc.
    Inventors: Chiaki Sano, Yoshimi Nagano, Kiyoshi Tanaka, Shigeho Ikeda, Masayoshi Naruse
  • Patent number: 4769474
    Abstract: A process for purifying tryptophan so as to contain almost no unreacted indole and a process for recovering unreacted indole with a very high percentage are provided, the purification process comprising passing a reaction fluid of tryptophan prepared from indole as raw material by means of an enzyme function, through a porous type, cation exchange resin layer, to cause the ion exchange part of the resin to absorb tryptophan, while to cause the porous part of the resin to adsorb indole, followed by eluting only the tryptophan with an alkali or acid aqueous solution, and the recovery process comprising subjecting tryptophan to repeated treatments of adsorption onto and elution from the ion exchange part of the resin and regeneration followed by eluting indole adsorbed onto the porous part of the resin with a water-containing organic solvent miscible with water and isolating indole from the resulting elute.
    Type: Grant
    Filed: April 2, 1986
    Date of Patent: September 6, 1988
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Shoichiro Miyahara, Toshio Matsumoto, Tooru Miyahara, Kazunari Nitta
  • Patent number: 4749786
    Abstract: Disclosed is the hydrocarboxylation of defined enamides with CO and a compound ROH to make amido acids or amido esters, either of which can be hydrolyzed to .alpha.-amino acids.
    Type: Grant
    Filed: April 6, 1987
    Date of Patent: June 7, 1988
    Assignee: The Standard Oil Company
    Inventors: Mark C. Cesa, James D. Burrington
  • Patent number: 4721803
    Abstract: In the process of hydrocarboxylating an .alpha.-enamide with CO and an organic hydroxyl compound to produce a N-acyl-.alpha.-amino acid ester, the improvement comprising using as the organic hydroxyl compound reactant, an organic hydroxyl compound which has a chiral center that is essentially all L or D, thereby producing a reaction mixture having essentially no enantiomeric pairs and containing diastereomeric N-acyl-.alpha.-amino acid esters having two chiral centers.
    Type: Grant
    Filed: October 29, 1985
    Date of Patent: January 26, 1988
    Assignee: The Standard Oil Company
    Inventors: Mark C. Cesa, Robert A. Dubbert, James D. Burrington
  • Patent number: 4718994
    Abstract: A method for perparing hydroxy compounds of the aromatic and heteroaromatic series of the general formula: ##STR1## wherein when R.sub.1 .dbd.--COOH, --CH.sub.2 CH(NH.sub.2)COOH then R.sub.2 .dbd.--OH, --H, --COOH; R.sub.3 .dbd.--H, --OH; R.sub.4, R.sub.5 .dbd.--H with no connecting bond; R.sub.6 .dbd.--OH; and when R.sub.1,R.sub.6,R.sub.3 .dbd.--H, R.sub.2 .dbd.--OH; then R.sub.4 .dbd.>NH; R.sub.5 .dbd.--CR.sub.7 .dbd.CHR.sub.4, where R.sub.7 .dbd.--CH.sub.2 --CH.sub.2 --NH.sub.2, --CH.sub.2 --CH(NH.sub.2)COOH, consists in that aromatic and heteroaromatic compounds of the general formula ##STR2## wherein when R.sub.1 .dbd.--COOH, --CH.sub.2 CH(NH.sub.2)COOH, then R.sub.2 .dbd.--OH, --H, --COOH; R.sub.3 .dbd.--H, --OH; R.sub.4,R.sub.5 .dbd.--H with no connecting bond; and when R.sub.1,R.sub.2,R.sub.3 .dbd.--H, then R.sub.4 .dbd.>NH; R.sub.5 .dbd.--CR.sub.7 .dbd.CHR.sub.4, where R.sub.7 .dbd.--CH.sub.2 --CH.sub.2 --NH.sub.2, --CH.sub.2 --CH(NH.sub.2)COOH.
    Type: Grant
    Filed: June 14, 1985
    Date of Patent: January 12, 1988
    Assignee: Latviisky Gosudarstvenny Universaitet Imeni P. Stuchki
    Inventors: Andrei K. Zhagars, Voldemar Y. Grinshtein, Sniedzite A. Ozola, Andris K. Zitsmanis, Avgust K. Arens
  • Patent number: 4710574
    Abstract: Disclosed is the hydrocarboxylation of defined enamides with CO and a compound ROH to make amino acids or amido esters, either of which can be hydrolyzed to .alpha.-amino acids.
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: December 1, 1987
    Assignee: The Standard Oil Company
    Inventors: Mark C. Cesa, James D. Burrington
  • Patent number: 4661606
    Abstract: Amino acids can be purified and/or concentrated by extracting aqueous mixtures such as fermentation broths by contacting an aqueous mixture containing amino acids with an organic solution containing a water insoluble extractant.
    Type: Grant
    Filed: June 6, 1984
    Date of Patent: April 28, 1987
    Assignee: Henkel Corporation
    Inventors: Francis W. Tuominen, Ronald R. Swanson, Phillip L. Mattison, Kenneth D. MacKay, Bradley W. Glorvigen
  • Patent number: 4644067
    Abstract: A process for the extraction of aromatic (e.g., phenyl-containing) amino acids from an aqueous phase (solution) containing them, comprising combining the aqueous phase with a tenside of the formulaR--U--SO.sub.3 XwhereinR is alkyl or cycloalkyl each of 4-18 carbon atoms; or phenyl or naphthyl, each optionally substituted by alkyl groups, and having up to 18 carbon atoms total.U is a carbon-to-sulfur bond or an oxygen atom, andX is an alkali metal ion;acidifying the aqueous phase to a pH value of 2.0-2.5; andextracting the aqueous phase with an alcohol, a ketone, or a carboxylic acid alkyl ester, each containing 4-6 carbon atoms.
    Type: Grant
    Filed: January 11, 1985
    Date of Patent: February 17, 1987
    Assignee: Schering Aktiengesellschaft
    Inventors: Alfred Weber, Detlef Wilke, Johannes Kurzidim, Mario Kennecke
  • Patent number: 4568754
    Abstract: Derivatives of 2-[3-(3-indolyl 2-amino propionyloxy] acetic acid corresponding to the following general formula I: ##STR1## in which R represents a hydrogen atom, a linear or branched alkyl radical including 1 to 12 carbon atoms, or a mono-alicyclic or polycyclic radical containing 5 to 16 carbon atoms, possibly linked by a methylene radical, and their pharmaceutically acceptable addition salts, are useful as medicaments for palliating deficiency of the serotoninergic system.
    Type: Grant
    Filed: March 7, 1984
    Date of Patent: February 4, 1986
    Inventors: Claude Laruelle, Marcel Lepant
  • Patent number: 4535167
    Abstract: Chiral N-protected, N-substituted .alpha.-amino acids are described. These compounds are prepared by condensation of an N-protected .alpha.-amino acid with an aldehyde followed by the selective reductive cleavage of an oxazolidinone intermediate.
    Type: Grant
    Filed: May 23, 1983
    Date of Patent: August 13, 1985
    Assignee: Merck & Co. Inc.
    Inventor: Roger M. Freidinger
  • Patent number: 4535177
    Abstract: Optical isomeric compounds having the general formula ##STR1## are prepared by: reacting by catalytic hydrogenation a compound of the formula ##STR2## with a compound of the formula ##STR3## wherein R, R.sub.1, R.sub.2 and R.sub.3 are as defined herein, to form a mixture of isomers in a ratio of L(S)L(S)>D(R)L(S); and recovering the (S,S) diastereomer by selectively precipitating an acid salt of the (S,S) ester from the solution.
    Type: Grant
    Filed: November 14, 1983
    Date of Patent: August 13, 1985
    Assignee: USV Pharmaceutical Corp.
    Inventors: Frederick A. Golec, Jr., Thomas Goetzen
  • Patent number: 4481362
    Abstract: Biochemical optical resolution of DL-tryptophanes in which DL-tryptophane amides are interacted with the culture products, or their treated products, of a microorganism capable of producing amidase is described. L-tryptophane amides in racemic DL-tryptophane amides are asymmetrically hydrolyzed to form optically active L-tryptophanes at a high yield and almost all D-tryptophane amides remain without being subjected to hydrolysis. The resultant D-tryptophane amides are readily hydrolyzed, after separating L-tryptophanes, to form optically active D-tryptophanes at a high yield.
    Type: Grant
    Filed: May 17, 1983
    Date of Patent: November 6, 1984
    Assignee: Ube Industries, Inc.
    Inventors: Mamoru Nakai, Tokio Ohshima, Tomio Kimura, Tetsuo Omata, Noritada Iwamoto