Sustainability in peptide chemistry: current synthesis and purification technologies and future challenges

Developing greener synthesis processes is an inescapable necessity to transform the industrial landscape, mainly in the pharmaceutical sector, into a long-term, sustainable reality. In this context, the renaissance of peptides as medical treatments, and the enforcement of more stringent sustainability requirements by regulatory agencies, pushed chemists toward the introduction of sustainable processes to prepare highly pure, active pharmaceutical ingredients (APIs). Innovative upstream (synthesis) and downstream (purification) methodologies have been developed during the last 5 years with the introduction and optimization of several technologies in solid-phase peptide synthesis (SPPS), liquid-phase peptide synthesis (LPPS), chemo-enzymatic peptide synthesis (CEPS), and chromatographic procedures. These innovations are also moving toward the introduction of continuous processes that represent one of the most important targets for iterative processes. This overview discusses the most recent efforts in making peptide chemistry greener. The extensive studies that were carried out on green solvents, reaction conditions, auxiliary reagents and purification technologies in the peptide segment can be useful to other fields of organic synthesis.