The invention relates to new sulfonamide Nav1.7 inhibitors and pharmaceutically acceptable salts thereof, to their use in medicine, to compositions containing them, to processes for their preparation and to intermediates used in such processes. Nav 1.7 inhibitors are potentially useful in the treatment of a wide range of disorders, particularly pain.
In a method for producing a de-dimethoxybenzylated compound by removing a dimethoxybenzyl group from a compound containing a dimethoxybenzyl group bonded to a nitrogen atom in the presence of an acid, the de-dimethoxybenzylated compound is obtained by removing the dimethoxybenzyl group without forming a poorly soluble product resulting from the removed dimethoxybenzyl group. The de-dimethoxybenzylation reaction is carried out in the presence of triphenylphosphine or diethylthiourea.