Patent ID: 8829157

Claim:
A process for the synthesis of Eptifibatide by Fmoc solid phase synthesis technique, the said process comprising: a) assembling a peptide chain consisting of six amino acids and a thioalkyl carboxylic acid in a required sequence on a solid support resin by coupling to one another by peptide bonds to obtain a peptide bound resin as given below: Mpa(trt)-Har(Pbf)-Gly-Asp(Otbu)-Trp-Pro-Cys(trt) Resin wherein the coupling of cysteine to the resin employs a combination of coupling solvents comprising DMF and DCM in the ratio in the range of 99:1 to 1:99; b) cleaving from the resin and deprotecting all the protecting groups with 87.5% TFA, 2.5% TIS, 5% DTT and 5% H 2 O to give SH-Eptifibatide with a purity of 82%; c) treating the peptide with hydrogen peroxide leading to instant oxidation obtaining Eptifibatide of formula 1; d) purifying the crude Eptifibatide of step c) by RP-HPLC to >99% purity by using C1-C4 alcohol wherein the binding capacity of C1-C4 alcohol is 3-5 fold over organic nitrile used.