14-carboxymethyl-1-[2-(1,3-dioxalan-2-yl)ethyl]-1'-(3,3-diethoxypropyl)-3,3-dimethyl-quinolinoindocarbocyanine ethyl ester 在
硫酸 作用下,
以
氯仿 为溶剂,
以44%的产率得到6,7,9,10-tetrahydro-14-carboxymethyl-16,16-dimethyl-7a-8a-guinolinoindolenine-[3,2-a,3'2'-a]pyrano[3,2-c;5,6-c']dipyridin-5-ium