14-carboxymethyl-1,1'-di(diethoxypropyl)-3,3-dimethyl--benzthiazolenine-indocarbocyanine ethyl ester 在
硫酸 作用下,
以
氯仿 为溶剂,
以90%的产率得到6,7,8,10-tetrahydro-14-carboxymethyl-16,16-dimethyl-7a-8a-benzathiozolenine-indolenine-[3,2-a,3'2'-a]pyrano[3,2-c;5,6-c']dipyridin-5-ium