thioxanthene-9-thione 、
1-hydrazinylidene-N,N-dimethyl-2,3-dihydrobenzo[f]thiochromene-3-carboxamide 在
iodobenzene diacetate 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以55%的产率得到Dispiro[N,N-dimethyl-3-carboxamide-2,3-dihydro-1H-naphtho[2,1-b]-thiopyran-1,2'-thiirane-3',9''-(9''H-thioxanthene)]