Multicomponent reactions (MCRs): an emerging toolbox for protein bioconjugation.

The bioconjugation of proteins is a powerful process that has tremendous applications in the fields of materials science and medicine. Multicomponent reactions (MCRs) provide an opportunity to conjugate at least two important molecules with a protein and furnish a versatile bioconjugate. In the last decade, bioconjugation chemistry has shown remarkable momentum with the involvement of different MCRs. Several MCRs have already been utilized to furnish valuable bioconjugates. Unfortunately, systematic reviews that describe this methodological development of protein bioconjugation utilizing MCRs are rare. Thus, in this review, we wish to showcase the methodological progress of the bioconjugation of proteins employing different MCRs with an emphasis of their postulated mechanisms. The article also highlights the wealth of untapped opportunities in the fields of analytical and medicinal chemistry, including the development of vaccines and antibody-drug conjugates.