Later, the same group found out that the derivative N-(7-((5-hydroxy-4oxo-2-phenyl-4H-chromen-7-yl)oxy)valeryl)-L-leucine (33) was shown to induce apoptosis and inhibit the activity of epidermal growth factor receptor (EGFR), a protein tyrosine kinase which is overexpressed in several cancers, beyond having the most potent activity with IC50 values of 16.6 μM against MCF-7 cells [134]. Here, EGFR is linked to cancer.