| 20110124866 | PROCESS FOR PREPARATION OF TADALAFIL - Process for the preparation of tadalafil of high pharmaceutical purity is characterized in that the sequence of reactions comprising acetylation of methyl (1R,3R)-1-(1,3-benzodioxol-5-yl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole-3-carboxylate with chloro acetyl chloride and cyclisation of the formed intermediate with methyl amine, is performed as a ‘one-pot’ process, without isolating the intermediate methyl (1R,3R)-1-(1,3-benzodioxol-5-yl)-2-(chloroacetyl)-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole-3-carboxylate. | 05-26-2011 |
