Synthesis of 2-benzylthiopyridine-4-carbothioamide derivatives and their antimycobacterial, antifungal and photosynthesis-inhibiting activity

Abstract

Aseries of 2-benzylthiopyridine-4-carbonitriles 4 and a series of 2-benzylthiopyridine-4-carbothioamides 5 were prepared. Their chemical structures were proved by IR and 1H NMR data and by elemental analysis. The MIC assessment was used for the estimation of their potential antimycobacterial and antifungal activity in vitro. The compounds were shown to be more active against mycobacterial strains than the tested fungi. Their antimycobacterial activity appears to be related mainly to the benzylthio moiety, while the antifungal activity appears to be related to the carbothioamide group. Substituents on the benzylthio moiety of derivatives 5 modified antifungal activity, whereas they did not play any significant role in antimycobacterial activity. The inhibiting effect of 4 and 5 on the photochemical activity of spinach chloroplasts was determined by IC 50 values. The compounds exhibited a moderate photosynthesis-inhibiting activity.