1246024-63-4Relevant articles and documents
Oligo(4-aminopiperidine-4-carboxylic acid): An unusual basic oligopeptide with an acid-induced helical conformation
Cho, Joon-Il,Tanaka, Masahiro,Sato, Sota,Kinbara, Kazushi,Aida, Takuzo
supporting information; experimental part, p. 13176 - 13178 (2010/12/19)
In sharp contrast with helical polypeptides carrying basic side chains, Api8, a basic oligopeptide containing the non-natural achiral amino acid 4-aminopiperidine-4-carboxylic acid (Api), adopts a helical conformation only in acidic media. Alkaline titration of a protonated Api8 oligomer appended with a leucine derivative at its N-terminus showed that disruption of its helical conformation occurs in a pH range of 7-10. NMR studies indicated that the piperidine groups in Api8, when nonprotonated, possibly interact with the proximal amide protons in the peptide backbone and hamper the formation of the H-bonding network responsible for the helical conformation. The helical structure is induced not only by protonation but also by acylation of the piperidine groups.