[(2E)-2-[(2E,4E)-5-[1,1-dimethyl-3-(sulfonatomethyl)benzo[e]indol-3-ium-2-yl]penta-2,4-dienylidene]-1,1-dimethylbenzo[e]indol-3-yl]methanesulfonate;[(2E)-2-[(E)-3-[3,3-dimethyl-1-(sulfonatomethyl)indol-1-ium-2-yl]prop-2-enylidene]-3,3-dimethylindol-1-yl]methanesulfonate;[(2E)-5-methoxy-2-[(E)-3-[5-methoxy-3,3-dimethyl-1-(sulfonatomethyl)indol-1-ium-2-yl]prop-2-enylidene]-3,3-dimethylindol-1-yl]methanesulfonate