ABSTRACT
Despite the dominance of solid-phase methods, the synthesis of peptides in solution remains one of the major chemical approaches to these molecules. The principal advantage of synthesis in solution is that intermediates can be isolated and characterized at every step, if necessary, so that chemists can always know which molecular species they are dealing with at any point. Peptide molecules can be synthesized by following either of two basic strategies: linear or convergent. A linear synthesis must, of necessity, be carried out in a sequential manner and probably by one person or at most by one team. Convergent strategies in which peptide segments are coupled together to give the desired target molecule appear, at least at first sight, to be the most promising for the synthesis of longer peptides, for several reasons. The protected peptide segments were deprotected either at the N-terminus by treatment with trifluoroacetic acid or at C-terminus by treatment with zinc dust in acetic acid, as appropriate.
