Benzofuran derivatives, their production and use

摘要

Compounds represented by the formula: wherein R¹ and R² are hydrogen atom, a hydrocarbon group or a heterocyclic group, or R¹ and R² may form, together with the adjacent carbon atom, a 3- to 8-membered homocyclic or heterocyclic ring, W indicates a group represented by the formula: wherein R⁴ indicates (1) an aliphatic hydrocarbon group, which may be substituted with an aromatic group, or (2) an acyl group containing an aromatic group, R⁵ is hydrogen atom, a C_1-6 alkyl, or an acyl group, R³ indicates a C_6-14 aryl group, or salts thereof. The compounds have an excellent action to inhibit neurodegeneration as well as an excellent brain penetrability and are low in the toxicity, thereby being useful as drugs for nerve degenerative diseases.