One-step synthesis of diaryloxadiazoles as potent inhibitors of BCRP.

Aim: BCRP plays a major role in the efflux of cytotoxic molecules, limiting their antiproliferative activity. We aimed to design and synthesize new BCRP inhibitors to render cancerous tumors more sensitive toward anticancer agents. Materials & methods: Based on our previous work, we conceived potential BCRP inhibitors derived from 1,3,4-oxadiazoles bearing two substituted phenyl rings. Results: Evaluating 19 derivatives, we found that 2,5-diaryl-1,3,4-oxadiazoles possessing methoxy groups were the most active. The highest activity was recorded with derivatives bearing three methoxy groups. The most active compound ( 3j ) was selective in inhibiting BCRP and nontoxic as evidenced by cellular tests. Conclusion: 3j is a promising BCRP inhibitor thanks to its synthetic accessibility and biological profile.