Fig. 2.

STD/CSP screening against EI. (a) Example STD-NMR spectra of a positive (top) and a negative (bottom) hit of the fragment screening. (b) The intensity of the STD spectra is plotted versus the pool index. Pools are ordered for decreasing intensity of the STD spectrum. The vertical dashed line indicates the best 25 pools that were counterscreened by CSP. STD signal intensities are normalized relative to the most intense STD spectrum. (c) ¹H-¹⁵N HSQC spectra of ¹⁵N-labeled EIC acquired in the absence (red) and in the presence (blues) of a pool of molecular fragments. Example of a negative (left) and a positive (red) hit are provided. (d) Binding isotherms obtained for the best six ligands of EI by NMR titration experiments (compounds 1–6). Experimental data are shown as circles. Modelling of the data is shown as solid lines. Color code is red, orange, green, yellow, blue, and light blue for compound 1, 2, 3, 4, 5, and 6, respectively. (e) Line structures of compounds 1–6. K_D values fitted from the binding isotherms are shown. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)