Patent ID: 6140515
Filing Date: 2000-10-31
Classification: C07D

Abstract:
A process for making compounds of formula I ##STR42## or a pharmaceutical salt thereof wherein R.sup.1 is selected from the group consisting of SCH.sub.3, --S(O).sub.2 CH.sub.3 and --S(O).sub.2 NH.sub.2 ;R.sup.2 is selected from the group consisting of OR, mono or di-substituted phenyl wherein the substituents are selected from the group consisting of methyl, chloro and F;R is unsubstituted or mono or di-substituted phenyl wherein the substituents are selected from the group consisting of methyl, chloro and F;R.sup.3 is H, C.sub.1-4 alkyl optionally substituted with 1 to 3 groups of F, Cl or Br andR.sup.4 is H, C.sub.1-4 alkyl optionally substituted with 1 to 3 groups of F, Cl or Br, with the proviso that R.sup.3 and R.sup.4 are not the same, the process comprising the steps of(a) reacting a compound of formula 3 ##STR43## wherein R.sup.1, R.sup.3 and R.sup.4 are described above; with a first ligand, a basic buffer, an oxidant and optionally a co-oxidant to yield a compound of formula 9 ##STR44## (b) oxidizing a compound of formula 9 with an oxidizing agent optionally in the presence of a first base to yield a compound of formula 1 ##STR45## wherein R.sup.1, R.sup.3 and R.sup.4 are described above; and (c) reacting a compound of formula 1 with a compound of the formula 2 ##STR46## wherein R.sup.2 is defined above, an acylating agent, optionally a dehydrating agent, a suitable catalyst, and a second base to yield a compound of formula I.