Synthesis and structure-activity relationship (SAR) study of 4-azabenzoxazole analogues as H3 antagonists

The synthesis and SAR of a novel series of 4-azabenzoxazole histamine H3 antagonists is described. Introduction of substituted phenyl, pyridyl and fused heterocyclic groups to the 6-position of the 4-azabenzoxazole core gave a series of compounds with good H3 antagonist activity in both ex vivo and in vivo assays.