Preparation of the Four Regioisomeric 2-(Methylthio)oxazolopyridines: Useful Synthons for Elaboration to 2-(Amino substituted)oxazolopyridines

摘要

2-Amino-substituted benzoxazoles 1 have beep incorporated in a variety of potential pharmaceutical agents (Figure 1). The related aza analogs, oxazolopyridines 2a-d are of interest since incorporation of a nitrogen in the benzenoid portion of the benzoxazole could favorably alter the physicochemical and pharmacokinetic properties of these derivatives. Thus, a practical and general route to compounds such as 2 was desirable wherein the amino substituent at position 2 could be easily varied.