Compounds for the treatment of autoimmune diseases

A method for the prevention or treatment of multiple sclerosis, acute-disseminated encephalomyelitis or autoimmune hepatitis, said method comprises the administration to a patient in need of such treatment of a therapeutically effective amount of a compound of general formula (I)

• wherein
• R1 and R2 represent, independently of each other:
• an optionally substituted phenyl ring, or
• an optionally substituted 5-membered heteroaromatic ring;
• one of R3 and R4 is H and the other represents a
• group wherein W is OH or an ortho-aniline group;
• each A, independently of each other, represents a —CH2— group or is absent;
• ═Y—Y═ is ═HC—CH═, ═N—CH═, or ═HC—N═;
• or a salt or solvate thereof.