The present invention provides a use of a compound to prepare a pharmaceutical composition for treating abnormal β-amyloid aggregation mediated diseases. The compound is represented by the following formula (I): wherein A, B, R1-R6are defined in the specification.本發明提供一種化合物用於製備治療不正常乙型-澱粉樣蛋白(β-Amyloid)聚集類疾病之醫藥組成物上之用途,該化合物係如下式(I)所示: 其中,A、B、R1-R6係如說明書中所定義。