Patents Assigned to Chirotech Technology, Ltd.
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Patent number: 6486347Abstract: A process for the preparation of a compound having the formula R3R4P—Ar—CO—X wherein Ar is an aryl group bearing the PR3R4 and COX groups in a 1,2-relationship, and optionally bearing also one or more non-interfering groups, R3 and R4 are each a hydrocarbon group optionally substituted by any non-interfering group, and X is OH or a non-interfering group, comprises (i) the reaction of NaPR3R4 with F—Ar—COX, or (ii) when X is an amine group, the reaction of R3R4P—Ar—COOY, OY being OH or a leaving group, with a solution of the amine obtained in situ by adding a base to a salt thereof. Certain ligands prepared by such a process are in a novel, crystalline form.Type: GrantFiled: March 29, 2001Date of Patent: November 26, 2002Assignee: Chirotech Technology, Ltd.Inventors: Ian Campbell Lennon, Ulrich Berens
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Patent number: 6479694Abstract: As process for the preparation of a cyclic carbamate of formula (1), comprises treatment of a cyclopentene of formula (2) wherein R1 is H or an organic group of up to 20 C atoms and R2 is C1-10 alkyl, aralkyl or aryl, with a source of halogen and a base.Type: GrantFiled: August 7, 2001Date of Patent: November 12, 2002Assignee: Chirotech Technology, Ltd.Inventor: Michael Lloyd
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Patent number: 6423522Abstract: A lactamase enzyme having good stability, capable of hydrolysing an enantiomer of the bicyclic lactam, 2-azabicyclo[2.2.1]hept-5-en-3-one, to give (−) lactam and (+) amino acid, has been found in a strain of Comamonas acidivorans. The enzyme has been isolated and cloned, and its structure identified.Type: GrantFiled: February 22, 2000Date of Patent: July 23, 2002Assignee: Chirotech Technology, Ltd.Inventors: Richard Anthony Wisdom, Caroline Susan Lee, Robert Christopher Brown
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Patent number: 6414187Abstract: The present invention pertains to a process for the preparation of an enantiomerically enriched chiral carboxylic acid derivative having the partial formula: C—C—C—COOX wherein X is a cation, comprising formation of a dehydro precursor salt having the partial formula: C═C—C—COOX by reaction of the corresponding precursor acid with an at least substantially stoichiometric amount of base, and asymmetric hydrogenation of the salt in the presence of a transition metal complex of a chiral phosphine ligand.Type: GrantFiled: December 5, 2000Date of Patent: July 2, 2002Assignee: Chirotech Technology, Ltd.Inventors: Mark Joseph Burk, Frank Bienewald, Antonio Zanotti-Gerosa
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Patent number: 6320068Abstract: The present invention pertains to a process for the preparation of an arylphosphine of the formula R1OC—Ar—PR2R3 wherein Ar is aryl or heteroaryl; R1 is an alkoxy or amine group; and R2 and R3 are each any organic group; and each of the respective groups may optionally be substituted with any non-interfering group; which comprises the reaction of a sulfonyloxy compound of the formula R1OC—Ar—OSO2R4 wherein R4 is alkyl, haloalkyl, perhaloalkyl, aryl, aralkyl or alkaryl, with a phosphine of the formula HPR2R3, in a solvent and in the presence of a palladium catalyst and a base. The arylphosphine can then readily be converted to a chiral phosphine ligand.Type: GrantFiled: November 15, 2000Date of Patent: November 20, 2001Assignee: Chirotech Technology, Ltd.Inventors: Stephen Benedict David Winter, Ian Campbell Lennon
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Patent number: 6228955Abstract: A process for preparing an optically-enriched chiral epoxide of formula I wherein R1, R2 and R3 are each independently selected from H, R, R—CO— and R—O—CO—, each R independently being substantially a hydrocarbon group of up to 20 carbon atoms, and X is an alkyl or cycloalkyl group of up to 10 carbon atoms, provided that —CO—X is not enolisable, which comprises the asymmetric epoxidation of a corresponding prochiral alkene of formula II R1R2C═CR3—CO—X (II) by reaction with an oxidant in the presence of a chiral catalyst. Many optically-enriched epoxides (I) are novel.Type: GrantFiled: October 20, 1997Date of Patent: May 8, 2001Assignee: Chirotech Technology, Ltd.Inventors: Stanley Michael Roberts, Brian Michael Adger
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Patent number: 6172249Abstract: An enantiomerically enriched compound of formula (4) or the opposite enantiomer thereof, wherein R is C1-10 alkyl. This compound, in the form of a transition metal complex, is useful as a catalyst for stereoselective hydrogenation.Type: GrantFiled: November 4, 1999Date of Patent: January 9, 2001Assignee: Chirotech Technology, Ltd.Inventors: Ulrich Berens, Mark Joseph Burk, Arne Gerlach
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Patent number: 6156935Abstract: A chiral phosphorus-based ligand, in single enantiomer form, which is capable of complexing a transition metal atom and of acting as a ligand in asymmetric chemical catalysts, which comprises the partial structureR.sup.1 R.sup.2 P--O--C--X--Y--C--O--PR.sup.1 R.sup.2 (I)wherein each of X and Y is C or a heteroatom; the C--X--Y--C chain forms part of a linearly-fused bicyclic structure; and either R.sup.1 and R.sup.2 are each independently H or an organic group of up to 20 carbon atoms, including alkyl, fluoroalkyl, aryl, alkylaryl, alkoxy, aryloxy, and alkylaryloxy, or PR.sup.1 R.sup.2 is cyclic such that R.sup.1 and R.sup.2 are covalently linked, optionally with additional substituents.Type: GrantFiled: May 29, 1998Date of Patent: December 5, 2000Assignee: Chirotech Technology, Ltd.Inventors: Stanley Michael Roberts, Christopher Palmer, Ulrich Berens
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Patent number: 6090616Abstract: A lactamase enzyme having good stability, capable of hydrolysing an enatiomer of the bicyclic lactam, 2-azabicyclo[2.2.1]hept-5-en-3-one, to give (-) lactam and (+) amino acid, has been found in a strain of Comamonas acidivorans. The enzyme has been isolated and cloned, and its structure identified.Type: GrantFiled: September 3, 1997Date of Patent: July 18, 2000Assignee: Chirotech Technology, Ltd.Inventors: Richard Anthony Wisdom, Caroline Susan Lee, Robert Christopher Brown
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Patent number: 6066737Abstract: The subject invention pertains to optically-enriched compounds of formula (1), wherein Ar is a C.sub.6-20 aryl group; and R.sup.1 and R.sup.2 are independently H, alkyl or aryl. The subject invention also pertains to method of preparing these compounds. The subject compounds can be prepared by reduction of the corresponding 1,4-dihydropyridine-3-aldehyde, e.g., using hydrogen an a catalyst. The aldehyde can be prepared by hydrolytic cleavage of an aminal obtainable by the reaction of 3-pyridinecarboxaldehyde and a chiral C-2 symmetric diamine, an then stereoselective introduction of the Ar and COOCHR.sup.1 R.sup.2 groups.Type: GrantFiled: June 29, 1998Date of Patent: May 23, 2000Assignee: Chirotech Technology, Ltd.Inventors: Brian Michael Adger, Gerard Andrew Potter, Martin Edward Fox
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Patent number: 6019994Abstract: Levobupivacaine or ropavicaine is used to treat migraine.Type: GrantFiled: March 3, 1998Date of Patent: February 1, 2000Assignee: Chirotech Technology, Ltd.Inventors: Ian Ashley Evetts, Simon John Gunning