AIDA-NMR 2D 1H-15N HSQCs (a-f)
Figure 1: a) human PD-1 (hPD-1); b) complex of hPD-1/hPD-L1; c) complex of hPD-1/hPD-L1 with Compound 1; d) complex of hPD-1/hPD-L1 with Compound 2. Compounds 1 and 2 are too weak inhibitors and do not dissociate the hPD-1/hPD-L1 complex; e) positive control of complex of hPD-1/hPD-L1 + Compound 1 + Reference compound. After addition of the Reference compound, a well-known PD-L1 inhibitor, the complex dissociates; f) complex of hPD-1/hPD-L1 + Compound 3; Compound 3 is a potent PD-L1 inhibitor and it dissociate the hPD-1/hPD-L1 complex and the spectrum of the PD-1 protein is recovered.