Studies in the synthesis of thiazolopyridines and bisthiazolopyridines. Part II

Abstract

Attempts to prepare derivatives of thiazolo[4,5-b]pyridine by the action of oxidising agents on substituted NN′-di-(2-pyridyl)thioureas were largely unsuccessful. The Hugershoff reaction, and oxidations by iodine, acid potassium permanganate, or alkaline sodium hypobromite gave compounds formulated as tetrahydro-1,4,2,5-dithiadiazines or NN′-di-(2-pyridyl)ureas. Alkaline potassium ferricyanide did, however, give small yields of the thiazolopyridines.