Sodium 2-((1E,3Z,5E)-5-(3,3-Dimethyl-5-sulfonato-1-(3-sulfonatopropyl)indolin-2-ylidene)-3-(3-(5-(2,5-dioxopyrrolidin-1-yloxy)-5-oxopentyl)phenyl)penta-1,3-dienyl)-3,3-dimethyl-1-(3-sulfonatopropyl)-3H-indolium-5-sulfonate → Sodium 2-((1E,3Z,5E)-5-(3,3-Dimethyl-5-sulfonato-1-(3-sulfonatopropyl)indolin-2-ylidene)-3-(3-(5-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethylamino)-5-oxopentyl)phenyl)penta-1,3-dienyl)-3,3-dimethyl-1-(3-sulfonatopropyl)-3H-indolium-5-sulfonate

Participants

Role	Name	HCID	Charge
Reactant	Sodium 2-((1E,3Z,5E)-5-(3,3-Dimethyl-5-sulfonato-1-(3-sulfonatopropyl)indolin-2-ylidene)-3-(3-(5-(2,5-dioxopyrrolidin-1-yloxy)-5-oxopentyl)phenyl)penta-1,3-dienyl)-3,3-dimethyl-1-(3-sulfonatopropyl)-3H-indolium-5-sulfonate	HCID 49782694	—
Reactant	Sodium 2-((1E,3Z,5E)-5-(1,1-Dimethyl-6,8-disulfonato-3-(3-sulfonatopropyl)-1H-benzo[e]indol-2(3H)-ylidene)-3-(3-(5-(2-(2,5-dioxo-2,5-dihydro4H-pyrrol-1-yl)ethylamino)-5-oxopentyl)phenyl)penta-1,3-dienyl)-1,1-dimethyl-3-(3-sulfonatopropyl)-1H-benzo[e]indolium-6,8-disulfonate	HCID 86649217	—
Product	Sodium 2-((1E,3Z,5E)-5-(3,3-Dimethyl-5-sulfonato-1-(3-sulfonatopropyl)indolin-2-ylidene)-3-(3-(5-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethylamino)-5-oxopentyl)phenyl)penta-1,3-dienyl)-3,3-dimethyl-1-(3-sulfonatopropyl)-3H-indolium-5-sulfonate	HCID 86649219	—

Compound 23 is prepared analogously to compound 21 (Example 27), except that compound 15 is used as a starting material.