Compounds 1-7 exhibited dose-dependent binding, with KD values ranging from 2.7 to 21 µM, consistent with the expected binding relative to the theoretical maximum. In contrast, compounds 8-11 demonstrated sub stoichiometric or weak binding (Figure , Supplement File S1). Interestingly, six of seven confirmed binders contained an aromatic cyano (a.k.a nitrile) group. Compounds 1-3, 5, and 6 shared a common 1-amino-4-cyano-dihydroindene group attached to the central amide, while compound 4 has a cyano-phenyl group attached to the central amide. Compound 7 contained a cyano-piperidine group, but it was appended to a non-aromatic piperidine. In compound 7 the acetylphenyl group may be mimicking the cyano-phenyl group.