| abstract |
A method of preparing a mixture of compounds V and VI: ** Formula ** or a pharmaceutically acceptable salt thereof, the method comprising treating a solution or suspension of compound. VII: ** Formula ** or a pharmaceutically acceptable salt thereof, in a solvent with hydrogen gas in the presence of a palladium catalyst and a substituted pyridine selected from the group consisting of 3-methoxypyridine, 3-ethylpyridine, 3-n -butylpyridine, 3-isobutylpyridine, 3-hydroxypyridine, 3-aminopyridine and 3-dimethylaminopyridine, 4- picoline, 4-methoxypyridine, 4-aminopyridine and 4-dimethylaminopyridine, in which an excess of compound V is produced compared to the compound SAW. |