Activities of thiotetrahydropyridines as antioxidant and antimicrobial agents

Abstract

Tetrahydropyridines have been reported previously as important medicinal agents. The present study, thiotetrahydropyridines were prepared and tested for antioxidants (DPPH and SOD assays) and antimicrobials (agar dilution method). The results show that 1-acetyl-1,2,3,4- and 1,2,3,6-thiotetrahydropyridines 15a-b, 16, 17 and 18a are new antioxidants that scavenge superoxide and free radicals. Whereas the analogs 15a and 16 are novel antimicrobials. Significantly, 1-acetyl-2-(1-adamantylthio)-3,4-diacetoxy-1,2,3,4-tetrahydropyridine (15a) is the most potent compound that inhibits the growth of Streptococcus pyogenes and Moraxella catarrhalis with MIC of 32 µg/mL, of Corynebacterium diphtheriae NCTC 10356 and of Vibrio cholerae (MIC of 64 µg/mL). Remarkably, the analog 15a is the most potent antioxidant and antimicrobial agent. This finding reveals a new and unique group of 1-acetyl-1,2,3,4-thiotetrahydropyridines as interesting lead compound with potential to be further developed for medicinal applications.