<p>Breast cancer is the most common cause of cancer cases among women worldwide estimated to cause 1 million deaths in 2040 [1]. Heterocycles are important building blocks of anticancer agents [2]. Of the aromatic heterocycle compounds, it has been widely reported that nitrogenbased heterocycles and benzothiazole derivatives have anticancer properties [2-4]. In this study, benzothiazol-2(3H)-one and [1,2,4]triazolo[4,3-b]pyridazine cores were merged and 5-chloro-3-((6-chloro-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methyl)benzo[d]thiazol-2(3H)-one compound was designed. The compound was synthesized by both conventional and microwave irradiation methods. It was evaluated against MCF-7 breast cancer cells<br></p>