“…For example, the coupling of N‐protected amino acid with Z ε ‐lysine or its corresponding ester in the presence of DCC/HOBT requires 18–24 h to achieve completion (3,4,8,10,11,13,17–19,26). In some cases, the final product is an ester and thus requires hydrolysis or hydrogenolysis as an additional step to obtain the desired free peptide (3,4,10,11,19,21,23–25).…”