Compound 1 docks into αIIbβ3 with an orientation similar to that of eptifibatide and tirofiban, but interacts only with αIIb; compound 1 docks into αVβ3 with a different and less favorable orientation compared with αIIbβ3. (A) Close-up view of the αIIbβ3 ligand binding site corresponding to the crystal structure of αIIbβ3 with bound eptifibatide (PDB entry 1TY6). (B) Most favorable docking mode of compound 1 in the same crystal structure. (C) Close-up view of the αIIbβ3 ligand binding site corresponding to the crystal structure of αIIbβ3 with bound tirofiban (PDB entry 1TY5). (D) The surface representation (1.4 Å probe radius) for the ligand binding site of αIIbβ3 with docked compound 1 is shown. Residue character is indicated by the following color designations: blue (basic), red (acidic), white (aliphatic), cyan (aromatic), and green (polar, mainly residues containing hydroxyl groups). (E) Surface representation of the ligand binding site of αVβ3 with docked compound 1. Visual Molecular Dynamics⁴⁸  (VMD) was used for all molecular graphics. (See Videos S1,S2 [available on the Blood website; see the Supplemental Materials link at the top of the online article] for additional visual representations of compound 1 docking into αIIbβ3 and αVβ3, respectively.)