Abstract: An enantiomerically enriched compound of formula 1,
wherein Ar is phenyl optionally substituted with one or more groups selected from haloalkyl, alkyl and halide. This compound can be isolated in crystalline form, and used in the preparation of (+)-16-[3-trifluoromethyl)phenoxy]-17,18,19,20-tetranor PGF2&agr; isopropyl ester.
Type:
Grant
Filed:
July 3, 2001
Date of Patent:
August 20, 2002
Assignee:
Chirotech Technology, Inc.
Inventors:
Philip Mark Jackson, Ian Campbell Lennon
Abstract: The present invention concerns compounds of the formula
wherein R1, R2, R3, R4 and R6 each represent H or an organic group of up to 20 C atoms, or any pair of R2 and R3 or R2 and R6 or R4 and R6 forms a cyclic group, and R5SO2 is a cleavable protecting group in which R5 is an organic group of up to 20 C atoms. These compounds are useful as intermediates in the synthesis of calanolide A and related antiviral compounds.
Abstract: A process for the preparation of an enantiomerically enriched 2-substituted succinic acid derivative of formula 2, which comprises asymmetric hydrogenation of the dehydro precursor of formula 7 or 8, or a mixture thereof
wherein R1 and R2 are independently H, a salt-forming cation, or an organic group of up to 30 C atoms, and R3 and R4 are independently H or an organic group of up to 30 C atoms, provided that R3 and R4 are not both H, in the presence of a transition metal complex of a chiral phosphine ligand having the partial formula 10
wherein n is 0 to 6 and R represents at least one non-hydrogen organic group of up to 30 C atoms.
Type:
Grant
Filed:
December 17, 1998
Date of Patent:
March 27, 2001
Assignee:
Chirotech Technology, Inc.
Inventors:
Mark Joseph Burk, Frank Bienewald, Martin Edward Fox, Antonio Zanotti-Gerosa
Abstract: Azlactone (3), or the opposite enantiomer thereof, undergoes biotransformation, using suitable enzymatic activity, in the presence of a compound YH to form a N-acyl-amino acid (2), wherein R1, R2 and R3 are each not hydrogen and are independently selected from groups containing up to 20 carbon atoms, optionally with any combination of R1, R2 and R3 being joined together to form at least one ring, X is selected from groups containing up to 20 carbon atoms, and Y is selected from the group consisting of —OH, -Oalkyl and -Nalkyl. Amino acid (1), or the opposite enantiomer thereof, can be prepared in high enantiomeric excess from N-acyl amino acid (2), by converting Y to OH.
Type:
Grant
Filed:
August 10, 1998
Date of Patent:
January 30, 2001
Assignee:
Chirotech Technology, Inc.
Inventors:
Nicholas Turner, James Winterman, Raymond McCague