Patent ID: 6538136
Filing Date: 2003-03-25
Classification: C07D

Abstract:
A process for the preparation of a compound of formula I: wherein R is hydrogen, C1-C6 alkyl, halo(C1-C6)alkyl, phenyl, benzyl, or phenyl substituted with from 1 to 3 substituents selected from the group consisting of F, Cl, Br, I, C1-C6 alkyl, C1-C6 alkoxy, halo(C1-C6)alkyl, phenyl, NO2, and CN; R1, R2, R3, R4, R5 and R6 are each independently hydrogen, C1-C6 alkyl, halo(C1-C6)alkyl, phenyl, or phenyl substituted with from 1 to 3 substituents selected from the group consisting of F, Cl, Br, I, C1-C6 alkyl, C1-C6 alkoxy, â€”S(C1-C6 alkyl), â€”S(phenyl), halo(C1-C6)alkyl, phenyl, NO2, and CN; or the pharmaceutically acceptable salt thereof; comprising combining a compound of formula II: wherein R1, R2, R3, and R4 are defined as above, a compound of formula III: wherein R5 is defined as above, and a compound of formula IV:Râ€”NH2â€ƒâ€ƒformula IV wherein R is defined as above, in the presence of a suitable acid; followed by addition of a suitable base and a compound of formula V: wherein R6 is defined as above.