Our latest paper describing novel fluorinated VHL ligands as spy molecules for 19F NMR screening is out in Chemical Communications

  • ToC graphics
  • Fig. 1 Design of a fluorinated spy molecule series. The co-crystal structure of VHL binder VH032 (PDB: 4W9H) inspired the choice of five positions (dashed circles) to attach a CF3 group, either on aromatic (series A and B) or aliphatic (C–E) regions.
  • Fig. 2 Evaluation of the sensitivity of a spy molecule. (a) Measurement of the transverse relaxation rate (R2) of the spy molecule in the absence (blue) and the presence of protein (red). The C2 quantifies the extent of the shift in R2 in the presence of protein. (b) Upon addition of protein, the 19F CPMG signal of a good spy molecule (left) is greatly reduced, resulting in a large window to detect and rank displacers, while for a poor spy molecule (right), the difference between the signals is too small.
  • Fig. 3 Relationship between sensitivity, affinity and position of the fluorinated group. (a) Correlation between C2 and the respective pKD of all the spy molecules where the affinity could be estimated, highlighting the regions where the sensitivity of the spy molecules decays considerably. Dashed circles display molecules with similar pKD that possess different C2 due to the variation in the fluorine attachment. The same plot was also made for the aromatic series A (b) and B (c), where the trend of an ide
  • Fig. 4 Binding response can be observed at low concentrations of spy molecule 19 and protein. (a) Overlay of the 19F CPMG peak (200 ms filter) of spy molecule 19 in the absence (blue) and presence of protein (red). When lowering the concentrations of spy molecule and protein, the S/N and C2 values respectively decreased. (b) Measurement of the C2 of spy molecule 19 at different concentrations (in triplicates), in the presence of four concentrations of protein. The error progressively increases as the conce
  • Fig. 5 Determination of the affinities of VHL binders using spy molecule 19. Displacement of spy molecule 19 in the presence of different concentrations of five VHL binders (molecules 3, 10, 12, 18 and 22) was concentration dependent. By knowing the concentrations of spy molecule (50 μM), and protein (1 μM) and the KD between spy molecule 19 and VHL, the Ki of each competitor was determined, having good correlation with the respective KD values obtained by SPR (top right inset graph).

Well done to Guilherme and congrats on his first first-author article!