19056-21-4 3,3'-(Carbonyliminobis(p-phenylenecarbonylimino))bis(1-propylpyridinium) ditosylate Pyridinium, 1-propyl-3-(p-(p-((1-propylpyridinium-3-yl)carbamoyl)benzamido)benzamido)-, di-p-toluenesulfonate