Fig. 1.

Crystal structures of 1 (yellow) and 2 (green) with the surface of the Notum palmitoleoyl binding pocket outlined (grey). Binding site residues shown within 3 Å of their respective ligands. Key hydrogen bond interactions are shown as dashed lines. Water molecules have been removed for clarity. Atomic coordinates have been deposited in the Protein Data Bank (PDB). PDB ID codes: 1: 6T2K; 2: 6T2H. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)