3-Cyano-6-phenyl-4-(3'-pyridyl)pyridine-2(1H)-thione, the related 2,2'-bis-pyridyldisulfide, 2-alkylthiopyridines and 2-amino-thieno[2,3-b]pyridines were synthesised and their neurotropic activities were examined. Bispyridyldisulfide exhibited low toxicity (LD 5 0 > 5 000 mg/kg, ICR mice, i.p.) and selective antiamesic activity at the doses of 0.05-0.5 mg/kg p.o. This effect was significantly higher than that induced by Piracetam at 50 mg/kg.