A peptide bond (amide bond) is a covalent chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, causing the release of a molecule of water (H2O), hence the process is a dehydration synthesis reaction (also known as a condensation reaction), and usually occurs between amino acids. The resulting −C∣∣O−NH− bonds is called a peptide bond, and the resulting molecule is an amide. The four - atom functional group −C∣∣O−NH− is called a peptide link.
Hence C represent a peptide chain having −C∣∣O−NH− link