Synthesis of some pyridyl substituted ureas and thioureas

Thirty five pyridyl-substituted ureas and thioureas were synthesized in order to study the relationship between chemical structure and biological activity. These compounds were obtained by the reaction of pyridylamines with isocyanates and isothiocyanates, as well as by the desulfurization of the corresponding thioureas. When tested, all these compounds exhibited weak physiological activity.