Figure 1: Chemical structure of amides and the conventional chemical method for amide bond synthesis. NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health. Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell. 4th. Citation: Judy Callis. (2014) The Ubiquitination Machinery of the Ubiquitin System. The Arabidopsis Book 11:e0174. doi:10.1199/tab.0174. elocation-id: e0174 Native chemical ligation or NCL is an important extension of the chemical ligation field, a concept for constructing a large polypeptide formed by the assembling of. Freeze drying. Freeze drying (also known as lyophilization) is a dehydration process typically used to preserve a perishable material or make the material more. Chemical or chemoenzymatic synthesis is an emerging approach to produce homogeneous glycoproteins, which are hard to obtain by conventional biotechnology method Introduction. The structural and functional characterization of proteins prepared by chemical synthetic methods has become a robust and practical route to the study. In organic chemistry, peptide synthesis is the production of peptides, which are organic compounds in which multiple amino acids are linked via amide bonds, also. a, The head-to-tail macrocyclization of a pentapeptide thioester catalysed by imidazole. b, The head-to-tail macrocyclization of a pentapeptide thioester with Sanger. What is peptide: A Simple Introduction of Peptide Synthesis. Peptides and proteins are linear polymers of amino acids linked by amide peptide bonds (Fig. 1).