TD52, an Erlotinib (HY-50896) derivative, is an orally active, potent cancerous inhibitor of protein phosphatase 2A (CIP2A) inhibitor. TD52 mediates the apoptotic effect in triple-negative breast cancer (TNBC) cells via regulating the CIP2A/PP2A/p-Akt signalling pathway. TD52 indirectly reduced CIP2A by disturbing Elk1 binding to the CIP2A promoter. TD52 has less p-EGFR inhibition and has potent anti-cancer activity. TD52 is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.