The reaction of propargyl bromide and 6-bromo-1,3-dihydro-imidazo[4,5-b]pyridin-2-one in refluxing dimethyl-formamide yields the title compound, C(12)H(8)BrN(3)O, which features nitro-gen-bound propadienyl and propynyl substituents. The imidazolopyridine fused ring is planar (r.m.s. deviation = 0.012 Å); the propadienyl chain is coplanar with the fused ring as it is conjugated with it, whereas the propynyl chain is not as the nitro-gen-bound C atom is a methyl-ene linkage. The acetyl-enic H atom is hydrogen bonded to the carbonyl O atom of an adjacent mol-ecule, forming a helical chain runnning along the b axis.