The multi-drug resistance (MDR) is a phenomenon in which cancer cells develop resistance to a variety of non-related chemotherapeutic drugs, and it is known that the overexpression of ABC transporters is involved in this resistance phenomenon. As well as the P-glycoprotein, the most known and studied ABC transporter, ABCG2(or BCRP) has caught the attention of different research groups around the globe and several efforts have been made understanding the structure and function of this transporter together with its substrates. One approach to overcome BCRP mediated drug resistance involves the use of potent inhibitors of BCRP transport. Recently, we described the synthesis of a new class of potent and selective ABCG2 inhibitors derived from tariquidar but due to the lack drug-like properties of the obtained compoundsherein we propose the development of new inhibitors with better pharmacological properties.