Eptifibatide is a cyclic heptapeptide containing 6 amino acids and 1 mercaptopropionyl (desamino cysteinyl) residue.

Eptifibatide is a cyclic heptapeptide containing 6 amino acids and 1 mercaptopropionyl (desamino cysteinyl) residue. An interchain disulfide bridge is formed between the cysteine amide and the mercaptopropionyl moieties. Chemically it is N6-(aminoiminomethyl)-N2-(3-mercapto1-oxopropyl-L-lysylglycyl-L-α-aspartyl-L-tryptophyl-L-prolyl-L-cysteinamide, cyclic (1→6)disulfide. Eptifibatide binds to the platelet receptor glycoprotein (GP) IIb/IIIa of human platelets and inhibits platelet aggregation. The eptifibatide peptide is produced by solution-phase peptide synthesis, and is purified by preparative reverse-phase liquid chromatography and lyophilized.