Patent number: 6372909
Abstract: Disclosed is a process for preparing a compound having the formula:
wherein R, R1, R2, R3, and R4 are independently selected from the group consisting of H, Br, Cl, F, alkyl, or alkoxy, by
(A) reacting a compound having the formula
wherein RA, RC, RD, and RE are independently selected from the group consisting of H, halo, alkyl, or alkoxy, and R5 is aryl or heteroaryl, with
a dehydrating agent to produce an imine having the formula:
(B) hydrolyzing the imine produced in step (A) to produce the compound having formula (I). Also disclosed are novel intermediates having the formula:
wherein RA, RB, RC, RD, and RE are independently selected from the group consisting of H, halo, alkyl, or alkoxy, and R5 is aryl or heteroaryl.
Type:
Grant
Filed:
November 18, 1999
Date of Patent:
April 16, 2002
Assignee:
Schering Corporation
Inventors:
Charles F. Bernard, Michael Casey, Frank Xing Chen, Denise C. Grogan, Marc Poirier, Robert P. Williams, Yee-Shing Wong, George G. Wu