Zinc-containing enzymes (carbonic anhydrases, CA) are playing an important role in metabolic processes of bicarbonate and carbon dioxide. From presently known 16 CA isoforms, the highest attention is paid to tumor associated CA IX. The waste majority of known CA inhibitors contains sulfonamide moiety as Zn-binding group. Expanding research on new anticancer agents we paid our attention to derivatives of thiophene-2-sulfonamide. Here we report thiol-free procedure for the synthesis of thiophene-2-sulfonamide thioethers based on derivatives of thiouronium salt.