Compound C6 displayed the most potent biological activity against B-RafV600E (IC50 = 0.15 μM) and WM266.4 human melanoma cell line (GI50 = 1.75 μM), being comparable with the positive control (Vemurafenib and Erlotinib) and more potent than our previous best compounds. Here, PPIB is linked to melanoma.