3-{2,4-Dioxo-3-[2-(4-o-tolyl-piperazin-1-yl)-ethyl]-3,4-dihydro-2H-thieno[3,4-d]pyrimidin-1-yl}-propionic acid 在
甲烷磺酸 、 phosphorus pentoxide 作用下,
以60%的产率得到4-[2-(4-o-Tolyl-piperazin-1-yl)-ethyl]-6,7-dihydro-1-thia-4,5a-diaza-acenaphthylene-3,5,8-trione