Resolution of the enantiomers of amlodipine
OwnerXitian Zhanginventor
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Abstract
The invention provides a feasible method for the separation of both (S)-(−)-enantiomer and (R)-(+)-enantiomer of racemic amlodipine with higher optically purity. The chiral reagent for separation is tartaric acid and the chiral auxiliary reagent is hexadeuterium dimethyl sulphoxide (DMSO-d6).
Claims4
A method for the separation of (R)-(+)- and (S)-(−)-isomers of amlodipine from mixtures thereof, which comprises the reaction of the mixture of isomers with D- or L-tartaric acid as a chiral reagent, wherein the mole ratio of tartaric acid to amlodipine is 0.25, in a) hexadeuterium dimethyl sulphoxide (DMSO-d6) or b) an organic solvent containing DMSO-d6 for precipitation of, respectively, a DMSO-d6 solvate of D-tartrate salt of (S)-(−)-amlodipine, or a DMSO-d6 solvate of a L-tartrate salt of (R)-(+)-amlodipine.
Dependencies are inferred from the claim text.