6，7－二甲氧基－2，4－二羟基喹唑啉合成工艺的改进

IMPROVED SYNTHESIS OF 6,7 DIMETHOXY-2,4-DIHYDROXYQUINAZOLINE

以藜芦醛（２）为原料经硝化－氧化得硝基酸４，再按类似物６－甲氧基－７－苄氧基－２，４－二羟基喹唑啉的合成法经酰氯－酰胺化、还原和环合反应合成了标题化合物１。对各步反应的工艺条件和后处理方法进行了改进，使从２至１的总收率达２０．６％。

The title compound was synthesized from veratraldehyde in 20.6% overall yield, via nitration, oxidation, chlorination, amidation, reduction and cyclization.