SYNTHESIS AND ANTITHYROID ACTIVITY OF PYRIDINE, PYRIMIDINE AND PYRAZINE DERIVATIVES OF THIAZOLE-2-THIOL AND 2-THIAZOLINE-2-THIOL

A series of compounds was synthesized by linking various derivatives o f pyridine, pyrimidine or pyrazine to thiazole-2-thiol or to its parti ally hydrogenated derivative 2-thiazoline-2-thiol. The reactions of th e compounds with molecular iodine and lactoperoxidase were examined in vitro. Their antithyroid activity was also examined in vivo in the ra t. T4 and TSH levels were determined, and the thyroid gland was examin ed histologically. 2-(3-Hydroxy-2-pyridyl)-2-thiothiazoline had the hi ghest antithyroid activity of the compounds tested (K(c) = 14931.mol-1 , IC50 0.65 x 10(-4) M, activity of thryoid gland + + +).