3-[N,N-bis(methoxycarbonylmethyl)aminomethyl]-5-nitrosalicylaldehyde 、 N-[N',N'-bis(methyloxycarbonylethyl)aminoethyl]-3,3-dimethyl-exo-methyleneindoline 以
乙醇 为溶剂,
以10%的产率得到Methyl 3-[2-[8-[[bis(2-methoxy-2-oxoethyl)amino]methyl]-3',3'-dimethyl-6-nitrospiro[chromene-2,2'-indole]-1'-yl]ethyl-(3-methoxy-3-oxopropyl)amino]propanoate