Side-chain loss reactions of collisionally activated protonated peptoids: A mechanistic insight

摘要: Abstract Peptoids constitute an emergent class of synthetic biocompatible macromolecules that are best described as polymers N-substituted glycines. Peptides and peptoids regioisomers with the side chains appended in to nitrogen atoms rather than α-carbon peptides. Peptide sequencing now takes great advantage collision-induced dissociation experiments, based on elucidation decomposition pathways protonated In contrast, data peptoid ion decompositions date scarcely present literature. Upon CID, were recently shown mostly dissociate by cleavages at backbone amide bonds yielding B- Y-fragment ions. addition, loss side-chain group and/or formation fragment common reactions for containing N-α-aromatic chain. paper, we submitted tailor-made (energy-resolved) experiments investigate reaction mechanisms. We also used orthogonal methods, such quantum chemistry, mobility spectrometry infrared photodissociation spectroscopy establish structures ended up different mechanistic scenarios consistent nature ions kinetic energy dependence reactions. Our proposals associate proton mobile model, bound dimer intermediacy concerted rearrangement