Compound 1 inhibits adhesion of cells expressing αIIbβ3 to fibrinogen, but does not inhibit adhesion of cells expressing αVβ3 to vitronectin. αIIbβ3-Expressing HEK293 cells or αVβ3-expressing CS1 cells were treated with DMSO (1%), compound 1 (100 μM), RGDS (1 mM), mAb 10E5 (20 μg/mL), or mAb 7E3 (20 μg/mL) for 15 minutes at 37°C. Cells were allowed to adhere to either immobilized fibrinogen or vitronectin, respectively, for 1 hour at 37°C. Nonadherent cells were removed by washing and the extent of cell adhesion was determined by pNPP assay as described in “Platelet and cell adhesion.” Adhesion is expressed as the percentage of cells adhering relative to the untreated cells. Means and SD are shown.