Topically active carbonic anhydrase inhibitors. 2. Benzo[b]thiophenesulfonamide derivatives with ocular hypotensive activity.

Derivatives of benzo[b]thiophene-2-sulfonamide were prepared to investigate their potential utility as topically active inhibitors of ocular carbonic anhydrase. Such an agent would be useful in the treatment of glaucoma. Among the compounds described are 6-hydroxybenzo[b]thiophene-2-sulfonamide (16) and its acetate ester (23), which are among the most potent ocular hypotensive agents in this class, as assessed in the alpha-chymotrypsinized rabbit. These compounds were selected for clinical evaluation.