2-[(3-Pyridinylmethyl)thio]pyrimidine derivatives: new bronchosecretolytic agents.

2-[(3-Pyridinylmethyl)thio]pyrimidine derivatives (1a-n) promote the excretion of phenol red into the mouse trachea, indicating an increased tracheobronchial secretion. Furthermore, 2-[(3-pyridinylmethyl)thio]pyrimidine (1a) (tasuldine) produces greater excretion of phenol red into the mouse trachea after systemic administration than the known bronchosecretolytic ambroxol. Compound 1a also reduces the viscosity of canine bronchial mucus. Compound 1a has been selected for clinical investigations.