Editing Peptoid (section)

==Chemical structure and synthesis==
[[File:Peptoid struc synth.png|frame|text-top|Structure (top) and synthesis (bottom) of peptoids highlighting the submonomer approach.]]
In peptoids, the side chain is connected to the nitrogen of the peptide backbone, instead of the α-carbon as in peptides. Notably, peptoids lack the amide hydrogen which is responsible for many of the [[secondary structure]] elements in peptides and proteins. Peptoids were first invented by Reyna J. Simon, Ronald N. Zuckermann, Paul Bartlett and Daniel V. Santi to mimic protein/peptide products to aid in the discovery of protease-stable small molecule drugs for the East Bay company [[Chiron Corporation|Chiron]].<ref name="pmid1409642">{{cite journal | vauthors = Simon RJ, Kania RS, Zuckermann RN, Huebner VD, Jewell DA, Banville S, Ng S, Wang L, Rosenberg S, Marlowe CK | display-authors = 6 | title = Peptoids: a modular approach to drug discovery | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 89 | issue = 20 | pages = 9367–9371 | date = October 1992 | pmid = 1409642 | pmc = 50132 | doi = 10.1073/pnas.89.20.9367 | doi-access = free }}</ref><ref>{{Cite web|title=What if We Could Give Viruses a One-Two Punch? by Berkeley Lab on Exposure|url=https://photostories.lbl.gov/what-if-we-could-give-viruses-a-onetwo-punch|access-date=2021-09-17|website=Exposure|language=en}}</ref>

Following the sub-monomer protocol originally created by Ron Zuckermann,<ref>{{cite journal | vauthors =  Zuckermann RN, Kerr JM, Kent SB, Moos WH | title = Efficient method for the preparation of peptoids [oligo(N-substituted glycines)] by submonomer solid-phase synthesis | journal = [[Journal of the American Chemical Society]] | date = 1992 | volume = 114 | issue = 26 | pages = 10646–10647 | doi = 10.1021/ja00052a076}}</ref> each residue is installed in two steps: [[acylation]] and displacement. In the acylation step, a haloacetic acid, typically [[bromoacetic acid]] activated by [[diisopropylcarbodiimide]] reacts with the amine of the previous residue. In the displacement step (a classical [[SN2 reaction|S<sub>N</sub>2 reaction]]), an amine displaces the halide to form the ''N''-substituted glycine residue. The submonomer approach allows the use of any commercially available or synthetically accessible amine with great potential for [[combinatorial chemistry]].