2-(1,3-Dibenzyl-imidazolidin-2-yl)-3-mercapto-5,5-dimethyl-cyclohex-2-enethione 、
丁炔二酸二甲酯 以
甲苯 为溶剂,
以19%的产率得到2,3-bis(methoxycarbonyl)-5(E)-<<1,2-bis(methoxycarbonyl)vinyl>thio>-7,7-dimethyl-7,8-dihydro-1',3'-dibenzylbenzo
thiopyran-4-spiro-2'-imidazolidine