4-[(E)-[1,1-Dioxo-1,2-benzothiazol-3-yl)-methyl-hydrazono]methyl]-2-methoxy-phenol has been used in the synthetic preparation of new 4-(1,1-dioxo-1,2-benzothiazol-3-yl)hydrazono]methyl]-2-methoxyphenols as inhibitors of the YAP/TAZ-TEAD interaction useful in treating malignant mesothelioma.