(5R,6S,7R)-6-(4-hydroxy-6-methyl-2-oxopyran-3-carbonyl)-7-(4-nitrophenyl)spiro[3,6,7,7a-tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazole-5,2'-acenaphthylene]-1'-one 、
异丙胺 以
二氯甲烷 为溶剂,
生成
dimethyl 10-cyclopentyl-2,4-diethyl-4H-pyrimido[1,2-a]benzimidazole-3,7-dicarboxylate