The novel RGDF mimetics 9a and 9b were synthesized with the use of 4-(isoindoline-5-yl)amino-4-oxobutyric acid as a surrogate of Arg-Gly motif. The synthesized compounds have demonstrated a high potency to inhibit platelet aggregation in vitro and to block FITC-Fg binding to 脦脦IIb脦脦3 on washed human platelets.