TRF1-TIN2 PPI-IN-1 (Compound 40) is a TRF1-TIN2 interaction inhibitor. TRF1-TIN2 PPI-IN-1 binds to the TRFH domain of TRF1 (KD = 29 μM) and competitively inhibits the binding of the TIN2 peptide (IC50 = 67 μM) . TRF1-TIN2 PPI-IN-1 disrupts the interaction between TRF1 and TIN2 by occupying the hotspot region of the TRF1-TIN2 binding interface. TRF1-TIN2 PPI-IN-1 can expel TRF 1 from the shelterin complex and can be used to study shelterin-related cancers[1].