PROCESS FOR THE SYNTHESIS OF N9-(3,5-DICHLORO-4-PYRIDYL)-6- DIFLUOROMETHOXYBENZO(4,5)FURO(3,2-C)PYRIDINE-9-CARBOXAMIDE AND SALTS THEREOF

摘要

The present invention relates to a process for the synthesis of N9-(3,5- dichloro-4-pyridyl)-6-difluoromethoxybenzo[4,5]furo[3,2-c]pyridine-9-carboxamide and salts thereof which are useful as a PDE4 inhibitor. The invention also relates to a process for the synthesis of methyl-2-formyl-7-cyclopentyloxybenzo[b]furan-4-carboxylate and salts thereof, which are useful as intermediates in preparing compounds with PDE4 inhibitory activity.