Racemization Per Se Or With Resolution Of Optical Isomers Patents (Class 564/302)
  • Publication number: 20140051888
    Abstract: A novel stereochemical mixture of 1,6-diaryl-2,5-diaminohexanes, such as a mixture of stereoisomers of 1,6-diphenylhexane-2,5-diamine, is described. Also described are methods of preparing stereochemically pure 1,6-diaryl-2,5-diaminohexanes, and particularly stereochemically pure 1,6-diphenyl-2,5-diaminohexane. Also described is the use of both the mixture of stereoisomers and the individual stereoisomers.
    Type: Application
    Filed: July 31, 2013
    Publication date: February 20, 2014
    Applicant: AMPAC FINE CHEMICALS LLC
    Inventors: William DUBAY, Jeffrey D. BUTLER, Charles L. LIOTTA
  • Publication number: 20130345475
    Abstract: Many optically active amines are valuable pharmaceuticals and intermediates for the preparation of active compounds. It is frequently the case that only one of the two enantiomers is active or not harmful, so that isolation of this enantiomer from the racemic mixture is necessary. Processes for racemate resolution make it possible to separate racemic mixtures into their enantiomers. Here, it is useful to once again racemize the enantiomer which is not required and recirculate it to racemate resolution and thus improve the yield of the desired enantiomer. The present invention relates to processes for the racemization of optically active amines, in particular arylalkylamines, in the presence of hydrogen and a hydrogenation/dehydrogenation catalyst comprising nickel, cobalt and copper as active components at elevated temperature.
    Type: Application
    Filed: June 20, 2013
    Publication date: December 26, 2013
    Inventor: Marcus Georg SCHREMS
  • Publication number: 20130296608
    Abstract: The present invention relates to a novel stereospecific synthesis of (?)(2S,3S)-1-dimethylamino-3-(3-methoxyphenyl)-2-methyl pentan-3-ol an intermediate in the synthesis of 3-[(1R,2R)-3-(dimethylamino)-1-ethyl-2-methylpropyl]phenol.
    Type: Application
    Filed: January 27, 2011
    Publication date: November 7, 2013
    Applicant: SYMED LABS LIMITED
    Inventors: Dodda Mohan Rao, Pingili Krishnareddy, Pingili Ramachandrareddy, Kirla Haritha, Kolluru Srinivas
  • Publication number: 20110306792
    Abstract: The present invention relates to a process for preparing tolterodine and the L-tartrate thereof. The preparation consists of the following steps: A) ammonolysis reaction between diisopropylamine and compound 2 (3,4-dihydro-6-methyl-4-phenyl-2H-benzopyran-2-one) activated by an activator to afford the amide 3; B) reduction of the amide by a reductant to give compound 1, i.e., racemic tolterodine free base; C) Resolution of the tolterodine free base to afford tolterodine L-tartrate. The present route is very short and suitable for industrial production.
    Type: Application
    Filed: August 18, 2009
    Publication date: December 15, 2011
    Applicant: 2Y-CHEM, LTD.
    Inventors: Gang Wang, Jingzhong Zhang, Xungui He, Yuan Wang
  • Patent number: 8067640
    Abstract: The present invention relates to a novel method for the preparation of diol intermediates having the formula (II) and/or the opposite enantiomer of an acylated diol having the formula (IV) useful for the preparation of escitalopram involving selective enzymatic acylation or deacylation.
    Type: Grant
    Filed: May 17, 2010
    Date of Patent: November 29, 2011
    Assignee: H. Lundbeck A/S
    Inventors: Naoki Taoka, Takahisa Kato, Shogo Yamamoto, Takashi Yoshida, Toshihiro Takeda, Yasuyoshi Ueda, Hans Petersen, Robert Dancer, Haleh Ahmadian, Lars O. Lyngso
  • Publication number: 20110230666
    Abstract: The present patent application relates to an improved process for the separation of enantiomerically pure compounds. Specifically it relates to separation of enantiomerically enriched Rivastigmine, Duloxetine, Escitalopram and their intermediates in high yields.
    Type: Application
    Filed: February 5, 2009
    Publication date: September 22, 2011
    Applicant: SHODHANA LABORATORIES LIMITED
    Inventors: Thota Giridhar, Gudipati Srinivasulu, Kotaru Srinivasa Rao
  • Patent number: 7968748
    Abstract: A process for resolving a compound in racemic form comprising the following steps is described: a) reacting a compound in racemic form with a resolving agent, b) forming a diastereoisomeric complex of the resolving agent and an enantiomer of interest, c) separating the enantiomer of interest from the obtained diastereoisomer, wherein such a process is characterized in that said resolving agent is a compound of Formula (I). A diastereoisomeric complex between the resolving agent of Formula (I) and the enantiomer of interest is also described. The process according to the invention allows acid and basic racemic mixtures to be separated.
    Type: Grant
    Filed: February 1, 2007
    Date of Patent: June 28, 2011
    Assignee: Abiogen Pharma S.p.A.
    Inventors: Elio Napolitano, Rita Fiaschi, Chiara Bechini, Gabriella Brunetto
  • Patent number: 7649114
    Abstract: The invention concerns a method for the isolation of a stereoisomer from a mixture comprising the two stereoisomers of the general formulae (I-A) and (I-A?) and/or the two stereoisomers of the general formulae (I-B) and (I-B?) in which R1, R2 and R3, identical or different, are selected from the group consisting of —H, —F, —Cl, —C1-C6-alkyl, —S—C1-C6-alkyl, —OH, —O—C1-C6-alkyl, —O—C1-C6-alkylenephenyl, —OCO—C1-C6-alkyl, —OCON(C1-C6-alkyl)2 and —O—SiR8R9R10 (in which R8, R9 and R10, identical or different, are —C1-C6-alkyl or -phenyl); R4 is —H or —C1-C6-alkyl; R5 is —C1-C6-alkyl; and R6 and R7, identical or different, are —H or —C1-C6-alkyl; or their salts with organic or inorganic acids; comprising the step (a) manipulating the mixture ratio of the stereoisomers in the mixture so that at least one of the stereoisomers is present in an enantiomeric excess.
    Type: Grant
    Filed: May 29, 2006
    Date of Patent: January 19, 2010
    Assignee: Gruenenthal GmbH
    Inventors: Helmut Heinrich Buschmann, Wolfgang Hell
  • Publication number: 20090292129
    Abstract: A process for resolving a compound in racemic form comprising the following steps is described: a) reacting a compound in racemic form with a resolving agent, b) forming a diastereoisomeric complex of the resolving agent and an enantiomer of interest, c) separating the enantiomer of interest from the obtained diastereoisomer, wherein such a process is characterized in that said resolving agent is a compound of Formula (I). A diastereoisomeric complex between the resolving agent of Formula (I) and the enantiomer of interest is also described. The process according to the invention allows acid and basic racemic mixtures to be separated.
    Type: Application
    Filed: February 1, 2007
    Publication date: November 26, 2009
    Applicant: ABIOGEN PHARMA S.P.A.
    Inventors: Elio Napolitano, Rita Fiaschi, Chiara Bechini, Gabriella Brunetto
  • Publication number: 20090023931
    Abstract: Disclosed is an alanine racemase chiral binaphthol derivative having the ability to recognize amino alcohols selectively on the basis of chirality and transform amino acids from an L-form into a D-form. Methods for the optical resolution of amino acid or amino alcohol and for the optical transformation of D- and L-forms of amino acids using the binaphthol derivative are also provided.
    Type: Application
    Filed: February 8, 2008
    Publication date: January 22, 2009
    Applicant: Ewha University - Industry Collaboration Foundation
    Inventors: Kim Kwan Mook, Tang Lijun
  • Patent number: 7408082
    Abstract: The present invention relates to a novel process for obtaining (1S,4S)N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthaleneamine from a mixture of its isomers. The process involves isomerising the 1-position and the 4-position and effecting separation of the desired isomer by methods such as fractured crystallization. The process can be operated as a continuous process.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: August 5, 2008
    Assignee: NPIL Pharmaceuticals (UK) Limited
    Inventor: John Blacker
  • Patent number: 7256313
    Abstract: The invention relates to processes for preparing 3-aminomethyl-3,5,5-trimethylcyclo-hexylamine (isophoronediamine, IPDA) having a high cis/trans isomer ratio. IPDA having a cis/trans isomer ratio in the range from 63/37 to 66/34 can be obtained in any desired cis/trans isomer ratio, irrespective of temperature, by reacting IPDA with H2 and NH3 in the presence of a hydrogenation catalyst. IPDA having a cis/trans isomer ratio of at least 73/27 which is an important starting material for the synthesis of polyurethanes and polyamides can be obtained by combining this isomerization process with distillative processes.
    Type: Grant
    Filed: August 6, 2003
    Date of Patent: August 14, 2007
    Assignee: BASF Aktiengesellschaft
    Inventors: Frank Funke, Thomas Hill, Jobst Rüdiger Von Watzdorf, Wolfgang Mattmann, Wolfgang Harder, Erhard Henkes, Gerd Littmann, Manfred Julius
  • Patent number: 6800764
    Abstract: A process is provided for preparing chirally pure S-enantiomers of &agr;-amino acids comprising the steps of: a) preparing an organometallic reagent from an alkyl halide of the formula (R)2CH(CH2)nCH2X; b) adding the organometallic reagent to carbon dioxide to afford a carboxylic acid; c) activating the carboxylic acid with an acid chloride, phosphorus trichloride, acid anhydride, or thionyl chloride in the presence of a tertiary amine base; d) reacting the product of step c) with an alkali metal salt of S-4-benzyl-2-oxazolidinone; e) treating the product of step d) with a strong non-nucleophilic base to form an enolate anion; f) trapping the enolate anion with 2,4,6-triisopropylbenzenesulfonyl azide to afford an oxazolidinone azide; g) hydrolyzing the oxazolidinone azide with an aqueous base to afford an &agr;-azido acid; h) reducing the &agr;-azido acid to the &agr;-amino acid; and i) recrystallizing the &agr;-amino acid to the chirally pure &agr;-amino acid.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: October 5, 2004
    Assignee: Wyeth
    Inventors: Anthony Frank Kreft, Madelene Miyoko Antane, Derek Cecil Cole, Dennis Martin Kubrak, Lynn Resnick, Joseph Raymond Stock, Zheng Wang
  • Patent number: 6753338
    Abstract: Methods and compositions are disclosed utilizing the optically pure (−) isomer of amlodipine. This compound is a potent drug for the treatment of hypertension while avoiding the concomitant liability of adverse effects associated with the racemic mixture of amlodipine. The (−) isomer of amlodipine is also useful for the treatment of angina and such other conditions as may be related to the activity of (−) amlodipine as a calcium channel antagonist such as cerebral ischemia, cerebral disorders, arrhythmias, cardiac hypertrophy, coronary vasospasm, myocardial infarction, renal impairment and acute renal failure, without the concomitant liability of adverse effects associated with the racemic mixture of amlodipine.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: June 22, 2004
    Assignee: Sepracor Inc.
    Inventor: James W. Young
  • Patent number: 6649607
    Abstract: The present invention relates to compositions comprising S-tofisopam substantially free of R-tofisopam, and methods for treating or preventing convulsions and/or seizures comprising administration of the composition to subjects in need of treatment therefor. Also provided are compositions and methods for treating or preventing convulsions and/or seizures comprising administering S-tofisopam substantially free of R-tofisopam with another anti-convulsant.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: November 18, 2003
    Assignee: Vela Pharmaceuticals, Inc.
    Inventors: Steven M. Leventer, Robert Kucharik
  • Patent number: 6576795
    Abstract: Optically active amines of the formula I where R1 and R2 are different and R1, R2, R3 are alkyl, cycloalkyl, arylalkyl, aryl, heteroaryl and heterocyclic radicals and R3 may also be hydrogen (H), with the radicals being able to bear substituents selected from the group consisting of alkyl, cycloalkyl, alkoxy, aryloxy, amino, alkylamino and dialkylamino, are racemized by reacting the optically active amine I in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst at elevated temperature, wherein the catalyst comprises the active components copper and zinc oxide and a support material.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: June 10, 2003
    Assignee: BASF Aktiengesellschaft
    Inventors: Frank Funke, Shelue Liang, Andreas Kramer, Rainer Stürmer, Arthur Höhn
  • Patent number: 6548704
    Abstract: Optically active amines of the formula I where R1 and R2 are different and R1, R2, R3 are alkyl, cycloalkyl, arylalkyl, aryl, heteroaryl and heterocyclic radicals and R3 may also be hydrogen (H), with the radicals being able to bear substituents selected from the group consisting of alkyl, cycloalkyl, alkoxy, aryloxy, amino, alkylamino and dialkylamino, are racemized by reacting the optically active amine I in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst at elevated temperature, wherein the catalyst comprises the active components copper and zinc oxide and a support material.
    Type: Grant
    Filed: December 12, 2001
    Date of Patent: April 15, 2003
    Assignee: BASF Aktiengesellschaft
    Inventors: Frank Funke, Shelue Liang, Andreas Kramer, Rainer Stürmer, Arthur Höhn
  • Patent number: 6500986
    Abstract: Racemic amino derivatives of the formula are prepared by a new process which comprises reacting an optically active amide of the formula in which with a strong base, optionally in the presence of an organic diluent and, if desired, reacting the resulting racemic amide. either a) with water in the presence of a base or an acid and optionally in the presence of an organic diluent, or b) if the compound of the formula (I) is an amide in which R3 is hydrogen, with an alkali metal hydroxide or an alkaline earth metal hydroxide.
    Type: Grant
    Filed: August 5, 1996
    Date of Patent: December 31, 2002
    Assignee: Bayer Aktiengesellschaft
    Inventors: Uwe Stelzer, Johannes Rudolf Jansen
  • Patent number: 6458955
    Abstract: Improved processes for preparation of high enantiomeric purity compounds center on resolution using simulated moving bed chromatography of a racemic precursor early in the synthesis. Resolution is effected with high enantiomeric purity, and subsequent reactions of the desired enantiomer performed with high optical specificity to maintain enantiomeric purity. The undesired enantiomer is racemized and recycled to the resolution phase to avoid loss.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: October 1, 2002
    Assignee: UOP LLC
    Inventor: Mark J. Gattuso
  • Patent number: 6455736
    Abstract: Improved processes for preparation of sertraline or sertraline analogs in high enantiomeric purity centers on resolution using simulated moving bed chromatography of isomeric racemic sertraline or sertraline analogs. Resolution is effected with high enantiomeric purity, and the undesired enantiomer may be racemized and recycled to the resolution phase to avoid loss.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: September 24, 2002
    Assignee: UOP LLC
    Inventors: Herman A. Zinnen, Mark J. Gattuso
  • Publication number: 20020120166
    Abstract: Optically active amines of the formula I 1
    Type: Application
    Filed: December 12, 2001
    Publication date: August 29, 2002
    Inventors: Frank Funke, Shelue Liang, Andreas Kramer, Rainer Sturmer, Arthur Hohn
  • Patent number: 6399826
    Abstract: Methods of making and using racemic and optically pure metabolites of sibutramine, and pharmaceutically acceptable salts, solvates, and clathrates thereof, are disclosed. Pharmaceutical compositions and dosage forms are also disclosed which comprise a dopamine reuptake inhibitor, such as a racemic or optically pure sibutramine metabolite, and optionally an additional pharmacologically active compound.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: June 4, 2002
    Assignee: Sepracor Inc.
    Inventors: Chrisantha Hugh Senanayake, Qun Kevin Fang, Zhengxu Han, Dhileepkumar Krishnamurthy
  • Patent number: 6316671
    Abstract: This invention relates to a method of splitting 1-amino-alkan-2-ol compounds of general formula: in which the group R can represent a wide variety of linear, branched or cyclic alkyl groups, comprising up to about 20 to 25 carbon atoms and preferably 1 to 15 carbon atoms. These groups can possibly have one or more double bonds, one or more hetero-atoms such as oxygen or sulfur so long as these are to be found separated from the asymmetric carbon atom by at least one carbon link and do not destroy the aliphatic nature of the group R. These groups can also be substituted by one or more halogen atoms such as chlorine or lower alkoxy groups such as methoxy or ethoxy groups.
    Type: Grant
    Filed: May 28, 1999
    Date of Patent: November 13, 2001
    Assignee: Universite de Rouen
    Inventors: Gerard Coquerel, Lionel Catroux, Yvette Combret
  • Patent number: 6297196
    Abstract: Benzoyl derivatives of the formula (I), process for their preparation and their use as herbicides and plant growth regulators are described. In this formula (I), R1, R2, R3, R4 and R5 are various organic radicals, Q is isothiazole, isoxazole, cyclohexanedione or a &bgr;-ketonitrile radical and A, B, E and X are divalent units containing one or more atoms.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: October 2, 2001
    Assignee: Hoechst Schering AgrEvo GmbH
    Inventors: Andreas Van Almsick, Lothar Willms, Thomas Auler, Hermann Bieringer, Christopher Rosinger
  • Patent number: 6162949
    Abstract: Improved processes for preparation of the (S)-oxetines in high enantiomeric purity centers on resolution using simulated moving bed chromatography of a racemic precursor early in the oxetine synthesis. Resolution is effected with high enantiomeric purity, and subsequent reactions of the desired enantiomer performed with high optical specificity to maintain enantiomeric purity. The undesired enantiomer may be racemized and recycled to the resolution phase to avoid loss.
    Type: Grant
    Filed: February 22, 1999
    Date of Patent: December 19, 2000
    Assignee: UOP LLC
    Inventor: Mark J. Gattuso
  • Patent number: 6160178
    Abstract: Optically active amines are racemized by reaction of the optically active amine in the gas phase at elevated temperature in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst.
    Type: Grant
    Filed: May 3, 1999
    Date of Patent: December 12, 2000
    Assignee: BASF Aktiengesellschaft
    Inventors: Hartmut Riechers, Joachim Simon, Arthur Hohn, Andreas Kramer, Frank Funke, Wolfgang Siegel, Christoph Nubling
  • Patent number: 6153797
    Abstract: In a process for racemizing optically active amines by reacting the optically active amine in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst at elevated temperature, the reaction is carried out in liquid phase and the catalyst comprises the catalytically active constituents copper, silver, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and/or platinum and a support material selected from the group consisting of aluminum oxide, zirconium dioxide, titanium dioxide, carbon and/or oxygen compounds of silicon.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: November 28, 2000
    Assignee: BASF Aktiengesellschaft
    Inventors: Hartmut Riechers, Joachim Simon, Arthur Hohn, Andreas Kramer, Frank Funke, Wolfgang Siegel, Christoph Nubling
  • Patent number: 6060624
    Abstract: A method for racemizing an enantiomer of an alkoxyamine represented by formula I ##STR1## in which R.sub.1 and R.sub.2 are the same or different C.sub.1 to C.sub.20 alkyl group. A feed containing an enantiomer of the alkoxyamine is passed over a nickel or cobalt catalyst in the presence of hydrogen and ammonia. The racemic mixture formed by this method contains substantially no by-products.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: May 9, 2000
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Kathryn Sue Hayes, Eugene George Lutz, Michael Gerard Turcotte
  • Patent number: 6049007
    Abstract: A process for the preparation of racemic amines of the formula I ##STR1## where R.sup.1 and R.sup.2 are different and R.sup.1, R.sup.2, R.sup.3 are alkyl, cycloalkyl, arylalkyl, aryl, heteroaryl and heterocyclic radicals and R.sup.3 can also be hydrogen, where the radicals can bear substituents selected from the group consisting of alkyl, cycloalkyl, alkoxy, aryloxy, amino, alkylamino and dialkylamino, which comprises simultaneously reacting in situ the corresponding optically active amine I and the secondary alcohol of the formula II and/or the unsymmetrical ketone of the formula III ##STR2## and the amine of the formula R.sup.3 NH.sub.2 in the presence of hydrogen and a hydrogenation catalyst or dehydrogenation catalyst at elevated temperature.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: April 11, 2000
    Assignee: BASF Aktiengesellschaft
    Inventors: Hartmut Riechers, Joachim Simon, Arthur Hohn, Andreas Kramer, Frank Funke, Wolfgang Siegel, Christoph Nubling
  • Patent number: 6034278
    Abstract: The invention concerns a new method for producing optically active 1-phenylethylamines, wherein (a) racemic 1-phenylethylamines are reacted with (S)-(-)-N-phenylcarbamate lactic acid in the presence of an aliphatic or aromatic hydrocarbon and in the presence of a lower aliphatic alcohol, wherein the reaction components are measured so that for every mole of racemic amine, between 0.25 and 0.5 mole of (S)-(-)-N-phenylcarbamate lactic acid are present, the reaction mixture is then concentrated at a liquid-phase temperature of up to 40.degree. C.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: March 7, 2000
    Assignee: Bayer Aktiengesellschaft
    Inventors: Walter Merz, Martin Littmann, Udo Kraatz, Christoph Mannheims
  • Patent number: 6002045
    Abstract: A process for racemising an optically-enriched chiral amine of the formula: R.sup.1 --CH(NR.sup.3 R.sup.4)--R.sup.2, wherein R.sup.1 is aromatic or unsaturated alkyl; R.sup.2 is aromatic or alkyl; and R.sup.3 and R.sup.4 are independently selected from hydrogen, alkyl and aryl; and wherein any combination(s) of two of the R groups may form a ring; comprises treatment of the optically-enriched amine with a metal hydroxide in an aprotic polar solvent.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: December 14, 1999
    Assignee: Chirotech Technology Limited
    Inventors: Jane Marie Paul, Gerard Andrew Potter
  • Patent number: 5977409
    Abstract: This invention relates to the use of a family of chiral .alpha.-substituted benzylamine reagents during chemical synthesis. Specifically, the reagents can be used in an auxiliary manner to deliver either a substituted or unsubstituted nitrogen atom while simultaneously bestowing an asymmetric bias toward the formation and separation of the diastereomeric intermediates that result from reaction of the reagents with racemic substrates also having one or more asymmetric atoms. The chiral auxiliary portion of the reagents can then be readily removed at some later and convenient stage of the overall synthetic scheme. The initial nitrogen-delivery reaction, asymmetric separation procedures, and removal of the chiral auxiliary can all be conducted under routine experimental conditions, including the final debenzylation, such that the overall method is adaptable to large-scale chemistry.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: November 2, 1999
    Assignee: University of Toledo
    Inventor: Paul W. Erhardt
  • Patent number: 5889186
    Abstract: Improved processes for preparation of the (S)-oxetines in high enantiomeric purity centers on resolution using simulated moving bed chromatography of a racemic precursor early in the oxetine synthesis. Resolution is effected with high enantiomeric purity, and subsequent reactions of the desired enantiomer performed with high optical specificity to maintain enantiomeric purity. The undesired enantiomer may be racemized and recycled to the resolution phase to avoid undesired losses.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: March 30, 1999
    Assignee: UOP
    Inventor: Mark J. Gattuso
  • Patent number: 5885787
    Abstract: In accordance with a novel process, (R)-amines of the formula ##STR1## in which R.sup.1, R.sup.2 and n have the meanings given in the description, can be prepared by reacting reating N-acyl-amines of the formula ##STR2## in which R.sup.1, R.sup.2, R.sup.3 and n have the meanings given in the description,with lipases which are suitable for cleaving the (R)-enantiomers of N-acyl-amines of the formula (II), in the presence of water and optionally in the presence of an organic diluent, at a pH of between 3.0 and 10.0 and at temperatures of between 0.degree. C. and 80.degree. C.
    Type: Grant
    Filed: August 25, 1997
    Date of Patent: March 23, 1999
    Assignee: Bayer Aktiegesellschaft
    Inventors: Hauke Smidt, Andreas Fischer, Peter Fischer, Rolf D. Schmid, Uwe Stelzer
  • Patent number: 5847215
    Abstract: A process for the racemization of optically active amines of the formula (I), where Ar is an unsubstituted or substituted aryl and R is alkyl, in whicha) (I) is reacted with the ketone (II) in which Ar and R have the same meanings as for (I), to give the condensation product (III), ##STR1## b) (III) is racemized by treatment with base, ##STR2## c) the arylalkylamine (I) is liberated as racemate from racemic (III) by reaction with optically active (I).
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: December 8, 1998
    Assignee: BASF Aktiengesellschaft
    Inventor: Klaus Ditrich
  • Patent number: 5763647
    Abstract: A process for preparing an optically active 1,4-bridged-cyclohexane carboxylic acid derivatives which are clinically important thromboxane A.sub.2 thromboxane of formula (IV): ##STR1## wherein, R is phenyl or phenyl substituted with hydroxy, lower alkoxy, halogen, or lower alkyl; Y is oxygen, methylene, substituted methylene; m is 0 or 1; n is 0, 1 or 2; q is 3 or 4 with the proviso that when m is 1, n is 0 or 1 from an optically active norbornyl amine derivative.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: June 9, 1998
    Assignee: Shionogi & Co., LTD.
    Inventors: Mitsuaki Ohtani, Hisanori Takahashi, Fumihiko Watanabe, Masami Takayama
  • Patent number: 5728885
    Abstract: A method of preparing the enantiomers of O-demethyltramadol and the use of the enantiomers as pain-killing drugs are described.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: March 17, 1998
    Assignee: Gruenenthal GmbH
    Inventors: Helmut Buschmann, Werner Winter, Ivars Graudums, Peter Jansen, deceased, Wolfgang Werner Alfred Strassburger, Elmar Josef Friederichs
  • Patent number: 5723667
    Abstract: A method of producing optically active tert-leucinol (formula I) of high enantiomeric purity ##STR1## by converting racemic (RS)-tert-leucinol into a diastereomeric salt pair by reaction with an optically active acid, removing the salt pair from solution by fractionated crystallization and separating therefrom the optically active acid to release the optically active tert-leucinol from the salt. The optically active acid used is an N-acylated tert-leucine of general formula VIII: ##STR2## in which R can be hydrogen or an alkyl-, arylalkyl- or aryl group with up to 20 C atoms and * signifies a chirality center.
    Type: Grant
    Filed: February 21, 1996
    Date of Patent: March 3, 1998
    Assignee: Degussa Aktiengesellschaft
    Inventors: Karlheinz Drauz, Wilfried Jahn, Michael Schwarm
  • Patent number: 5663368
    Abstract: This invention relates to novel diastereomeric acid addition salts of homochiral hydroxylamines, to processes for obtaining such, to processes for the conversion thereof to the corresponding homochiral hydroxylamines, to certain novel homochiral hydroxylamines and the processes for using these as intermediates.
    Type: Grant
    Filed: April 11, 1996
    Date of Patent: September 2, 1997
    Assignee: Smithkline Beecham Corporation
    Inventors: Joseph R. Flisak, Stephen Torey Ross
  • Patent number: 5639913
    Abstract: Novel derivatives of 1-aminoindan and their salts are described. Optically active 1-aminoindan derivatives are prepared by reacting a N-benzyl analog of the desired compound with an enantiomer of mandelic acid.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: June 17, 1997
    Assignee: Teva Pharmaceutical Industries, Ltd.
    Inventors: Ramy Lidor, Eliezer Bahar
  • Patent number: 5510519
    Abstract: Disclosed are optically active secondary amine compounds and salts thereof having the general formula (I): ##STR1## a process for the preparation of the optically active secondary amine compounds and salts thereof, and the use of such compounds. Such compounds exhibit a high resolution power and hence are useful agents for optical resolution.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: April 23, 1996
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Yukio Yoneyoshi, Junko Kudo, Toshio Nishioka
  • Patent number: 5476964
    Abstract: Benzyl alcohols having a chiral center at the benzylic carbon can be conveniently racemized by treatment with solid acids which are strongly acidic cation exchange materials. Racemization may be effected generally in the range from 20.degree.-150.degree. C. in aqueous or partly aqueous systems in combination with a water-miscible organic solvent to improve solubility of the alcohol. Similar racemizations may be effected for benzyl ethers and esters. This process is valuable for recycling of unwanted enantiomers obtained in the resolution of racemic mixtures.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: December 19, 1995
    Assignee: UOP
    Inventor: David W. House
  • Patent number: 5391634
    Abstract: Optically-active, amphiphilic, free-radical addition copolymers having an optically-active hydrophobic portion and an ionic hydrophilic portion are effective resolving agents. This utility is based on a unique combination of properties, viz., water solubility, chirality and amphiphilicity, i.e., having a dual hydrophobic and hydrophilic nature.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: February 21, 1995
    Assignee: The Dow Chemical Company
    Inventors: Mladen Ladika, Thomas E. Fisk
  • Patent number: 5391735
    Abstract: The present invention relates to a new process for the preparation of 3-substituted derivatives of 1-amino-2-hydroxy-propane in the form of single diastereoisomers, to certain of these diastereoisomers, and to compounds which are intermediates in the new process of the invention.
    Type: Grant
    Filed: April 12, 1994
    Date of Patent: February 21, 1995
    Assignee: Farmitalia Carlo Erba S.p.A.
    Inventors: Piero Melloni, Arturo D. Torre, Ettore Lazzari, Giuseppe Mazzini
  • Patent number: 5298660
    Abstract: Disclosed are optically active secondary amine compounds and salts thereof having the general formula (I): ##STR1## a process for the preparation of the optically active secondary amine compounds and salts thereof, and the use of such compounds. Such compounds exhibit a high resolution power and hence are useful agents for optical resolution.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: March 29, 1994
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Yukio Yoneyoshi, Junko Kudo, Toshio Nishioka
  • Patent number: 5292893
    Abstract: A process is provided for catalytically reducing imines, oximes, hydrazones and related compounds. Moreover, there is provided a process for the catalytic asymmetric reduction of imines, oximes, hydrazones, and the like, using enantiomerically enriched catalysts, to provide chiral amine reaction products which are enriched in one enantiomer. Catalytic asymmetric reduction can also be carried out using an achiral precatalyst in combination with aThe U.S. Government has rights in this invention pursuant to NIH Grant Number GM 34917.
    Type: Grant
    Filed: November 14, 1991
    Date of Patent: March 8, 1994
    Assignee: Massachusetts Institute of Technology
    Inventors: Stephen L. Buchwald, Christopher A. Willoughby
  • Patent number: 5284966
    Abstract: Intermediates for transforming (2S,3S)-2-amino-3-phenyl-1,3-propanediols into their (2R,3R)-enantiomers are described. The final compounds are useful intermediates for the synthesis of antibiotics like Chloramphenicol, Thiamphenicol and Florfenicol.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: February 8, 1994
    Assignee: Zambon Group S.p.A.
    Inventors: Marco Villa, Claudio Giordano, Silvia Cavicchioli, Silvio Levi
  • Patent number: 5284976
    Abstract: A novel process for producing hindered and unhindered primary amines represented by the formula RNH.sub.2 and R*NH.sub.2 in high yields from novel intermediates RBMe.sub.2 or R*BMe.sub.2 wherein R is an organo group, R* is a chiral organo group. attached to boron, B is boron and Me is methyl.
    Type: Grant
    Filed: July 19, 1993
    Date of Patent: February 8, 1994
    Assignee: Aldrich Chemical Company, Inc.
    Inventor: Herbert C. Brown
  • Patent number: 5281750
    Abstract: The present invention relates to chiral supports and to their use in the asymmetric synthesis, deracemization and optical inversion of organic chiral compounds. In particular, the supports are used in combination with thermal equilibration of a species having a reactive achiral portion. Preferably, these supports are obtained by the copolymerization of at least one chiral unit and at least one functionalizing unit or by the polymerization of at least one chiral unit which is a source of said functionalizing unit. Optionally, a crosslinking agent is utilized. By utilizing these supports and thermal equilibration, excess enantiomers can be produced.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: January 25, 1994
    Assignee: Rhone-Poulenc Chimie
    Inventors: Robert Jacquier, Monique Calmes, Jacques Daunis
  • Patent number: 5280093
    Abstract: The present invention relates to chiral polymers and to their uses for operations of asymmetric synthesis, deracemization and optical inversion.These polymers are characterized in that they comprise:a chiral unita functionalizing unitan optional crosslinking unitApplication to chiral organic synthesis.
    Type: Grant
    Filed: April 14, 1993
    Date of Patent: January 18, 1994
    Assignee: Rhone-Poulenc Chimie
    Inventors: Robert Jacquier, Monique Calmes, Jacques Daunis