5-((1,4-(dicarboxymethyl)-5-(2,3-dihydroxypropyl)-2-pyrrolo(3,2-b)pyrrolyl)methine)-1,4-(dicarboxymethyl)-2-(1,2,3-trihydroxypropyl)pyrrolo(3,2-b)pyrrolylium
5-((1,4-(dicarboxymethyl)-5-(2,3-dihydroxypropyl)-2-pyrrolo(3,2-b)pyrrolyl)methine)-1,4-(dicarboxymethyl)-2-(1,2,3-trihydroxypropyl)pyrrolo(3,2-b)pyrrolylium