Isoxyl

Isoxyl (Thiocarlide; 4,4'-diisoamyloxydiphenylthiourea) is a thiourea chemical that was used in the 1960s to successfully treat tuberculosis (TB). It has considerable antimycobacterial activity in vitro and is effective against multi-drug resistant strains of Mycobacterium tuberculosis. Isoxyl inhibits M. bovis with six hours of exposure, which is similar to isoniazid and ethionamide, two other prominent anti-TB drugs. Unlike these two drugs, however, isoxyl also partially inhibits the synthesis of fatty acids.

Isoxyl was developed by a Belgian company, Continental Pharma S.A. Belgo-Canadienne in Brussels, Belgium. The head researcher was Professor N. P. Buu-Hoi, head of Continental Pharma's Research Division.