409320-08-7Relevant academic research and scientific papers
Controlling the sign and magnitude of screw-sense preference from the C-terminus of an achiral helical foldamer
Le Bailly, Bryden A. F.,Clayden, Jonathan
supporting information, p. 7949 - 7952 (2014/07/08)
The global screw-sense preference of an achiral helical oligomer may be controlled by a single chiral monomer located at one terminus. Remarkably, maximal control is induced in oligomers of the achiral quaternary amino acid Aib by a single C-terminal alaninamide residue, probably because the Ala side chain, though small, is compatible with a 310 helical conformation. The presence or absence of a C-terminal hydrogen bond donor determines the screw sense of the entire oligomer. the Partner Organisations 2014.
Nitroxyl peptides as catalysts of enantioselective oxidations
Formaggio, Fernando,Bonchio, Marcella,Crisma, Marco,Peggion, Cristina,Mezzato, Stefano,Polese, Alessandra,Barazza, Alessandra,Antonello, Sabrina,Maran, Flavio,Broxterman, Quirinus B.,Kaptein, Bernard,Kamphuis, Johan,Vitale, Rosa Maria,Saviano, Michele,Benedetti, Ettore,Toniolo, Claudio
, p. 84 - 93 (2007/10/03)
The achiral, nitroxyl-containing α-amino acid TOAC (TOAC = 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid), in combination with the chiral α-amino acid Cα-methyl valine [(αMe)Val], was used to prepare short peptides (from di- to hexa-) that induced the enantioselective oxidation of racemic 1-phenylethanol to acetophenone. The best catalyst was an Nα-acylated dipeptide alkylamide with the -TOAC-(αMe)Val- sequence folded in a stable, intramolecularly hydrogen-bonded β-turn conformation with large, lipophilic (hydrophobic) N- and C-terminal blocking groups. We rationalized our findings by proposing models for the diastereomeric intermediates between (R)-[and (S)]-1-phenylethanol and the catalyst Fmoc-TOAC-L(αMe)Val-NHiPr, based on the X-ray diffraction structure of the latter.
