6,7-dihydro-9,10-dimethoxy-2-mesitylamino-7-methyl-4H-pyrimido[6,1-a]isoquinolin-4-one 、
碘甲烷 、
potassium carbonate 在
氯仿 、 silica gel 作用下,
以
丙酮 为溶剂,
以There are obtained 9.4 g of pure 9,10-dimethoxy-3,7-dimethyl-2-mesitylimino-2,3,6,7-tetrahydro-4H-pyrimido[6,1-a]isoquinolin-4-one, m.p. 156°-157° C的产率得到9,10-dimethoxy-3,7-dimethyl-2-mesitylimino-2,3,6,7-tetrahydro-4H-pyrimido[6,1-a]isoquinolin-4-one