For the synthesis of compound A ((E)-4-((3,5-dichloro-2-hydroxybenzylidene)amino)benzamide) two methods were followed: the first is mechanochemical (Zbačnik & Kaitner, 2014 ▸) grinding and the second is a conventional reaction with azeotropic removal of water (Scheme S1) (Safin et al., 2014 ▸).