Synthesis of Peptides by Solution Methods

Peptides are essentially small version of proteins and the structure of peptides is best described as a chain of amino acids linked to each other through amide bonds. In the chemical synthesis of peptides, two procedures are primarily used, although they are both based on fundamentally same principles one is a solution method and the other being a solid-phase method carried out on a resin. The chemistry of peptide synthesis was developed based on the following basic chemical principles 1) selection of protecting groups for amino acids and deprotection and 2) peptide bond formation. Therefore, studies on peptide synthesis in solution can be directly applied to solid phase methodology. This review deals with the fundamental chemistry of peptide synthesis in solution and considers the following points (1) principle of peptide synthesis, (2) protection procedures, (3) chain elongation procedures by either stepwise or segment condensation reactions and (4) final deprotection of protected peptides. Keywords: Synthesis of Peptide, Solution Methods, Solid phase methodology, peptide bond formation, Chain elongation procedure, Urethane protected, C terminus, Benzyloxycarbonyl group, Triphenylmethyl group, Fmoc amino acids, Tetrabutyl, Methyl Ester, tert Butyl Ester, Phenacyl Esters, Guanidino Group, Aliphatic Hydroxy Function, Indole Nitrogen, Segment Condensatio, Azide procedure, Catalytic Hydrogenation, Final Deprotection, Hard soft Acid