2,3-dihydro-1H-pyrido[2,3-b][1,4]oxazin-7-carbonitrile 、
3,5-dibromo-4-methoxybenzoyl chloride 以to obtain 1-(3,5-dibromo-4-methoxy-benzoyl)-2,3-dihydro-1H-pyrido[2,3-b][1,4]oxazin-7-carbonitrile as white solid (14.4 mg, 74%)的产率得到1-(3,5-dibromo-4-methoxy-benzoyl)-2,3-dihydro-1H-pyrido[2,3-b][1,4]oxazin-7-carbonitrile