Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Reexamination Certificate
2006-08-22
2006-08-22
Saeed, Kamal A. (Department: 1626)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
Reexamination Certificate
active
07094920
ABSTRACT:
A process is described for the stereospecific preparation of an ester of formula (I): wherein * signifies the (R) stereoisomer; R1is selected from C1-6alkyl, preferably ethyl; and R2is hydrogen, a protecting group or a leaving group which process comprises reaction of a nitrile of formula (II): wherein * signifies the (R) stereoisonomer; and Ph is the phenyl group C6H5with a solution of an inorganic acid in an alcohol and optional conversion of the compound of formula (I) wherein R2is H so prepared to any other desired compound of formula (I) by standard methods in the art. The compounds of formula (I) are chiral esters, useful as intermediates in the synthesis of the family of acetylcholine esterase (ACE) inhibitors known as “prils”, such as lisinopril, cilazapril, enalapril, benazepril, ramipril, delapril, enalaprilat, imidapril, spirapril, trandolapril and others.in-line-formulae description="In-line Formulae" end="lead"?*in-line-formulae description="In-line Formulae" end="tail"?in-line-formulae description="In-line Formulae" end="lead"?Ph-CH2—CH2—CH(OR2)—COOR1 (I)in-line-formulae description="In-line Formulae" end="tail"?in-line-formulae description="In-line Formulae" end="lead"?*in-line-formulae description="In-line Formulae" end="tail"?in-line-formulae description="In-line Formulae" end="lead"?Ph-CH2—CH2—CH(OH)—CN (II)in-line-formulae description="In-line Formulae" end="tail"?
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Chung Susannah L.
Fermenta Biotech Limited
Saeed Kamal A.
Schwegman Lundberg Woessner & Kluth P.A.
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