Synthesis and Properties of 3-Amino-4-(4-methoxyphenyl)-6-oxo-4,5,6,7-tetrahydrothieno[2,3-b]pyridines

Abstract

A series of previously undescribed 3-amino-4,5,6,7-tetrahydrothieno[2,3-b]pyridines was prepared in 44–79% yields through alkylation of N-methylmorpholinium 3-cyano-4-(4-methoxyphenyl)-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolate followed by Thorpe–Ziegler cyclization in the presence of KOH. An in silico predictor analysis was conducted to determine the bioavailability parameters and potential protein targets for the new compounds. Under laboratory experimental conditions on sunflower seedlings, some of the synthesized compounds demonstrated a moderate antidote effect against the herbicide 2,4-D.