Fig. 1. Overview of the NMR restraints for the compounds 1, 2 and 3, displayed in panel a–c respectively. Left) Intermolecular cross-peaks from F1-[¹⁵N,¹³C]-filtered [¹H,¹H]-NOESY spectra of PIN1 in complex with the corresponding fragments. The protein methyl groups involved in inter-molecular NOE(s) are arbitrarily named M1 to M5 and the ligand resonance assignments are reported in Table S1.† Middle) Intermolecular distance restraint network between the assigned fragment's protons and the unknown protein's methyl groups. The red lines show the restraints that are shared between all the fragments, the orange lines represent restraints that are shared between two fragments, and the black lines represent restraints that are specific to the considered fragment. Right) Structures of the fragments. The isosteric groups are emphasized by the green dashed circles.