title: Chiral, fully extended helical peptides.
abstract: The synthesis of the N-protected (blocked) homo-peptide esters from the chiral C(α)-ethyl, C(α)-n-pentylglycine was performed in solution to the hexapeptide level. The conformational propensity exhibited by these oligomers in chloroform solution and in the crystal state was assessed by use of FTIR absorption, NMR, and X-ray diffraction. The results indicated that fully extended helical structures (2.0(5)-helices) are overwhelmingly adopted irrespective of the peptide main-chain length. This oligomeric series is of great interest as it is characterized by the longest C ( i )(α) ,…, C ( i+1 )(α) (per residue) separation achievable in the class of chiral, rigid, helical peptide spacers based on α-amino acids.
authors.affiliation: ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, via Marzolo 1, 35131 Padua, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Crisma
authors.forename: Alessandro
authors.initials: A
authors.lastname: Moretto
authors.forename: Cristina
authors.initials: C
authors.lastname: Peggion
authors.forename: Lavinia
authors.initials: L
authors.lastname: Panella
authors.forename: Bernard
authors.initials: B
authors.lastname: Kaptein
authors.forename: Quirinus B
authors.initials: QB
authors.lastname: Broxterman
authors.forename: Fernando
authors.initials: F
authors.lastname: Formaggio
authors.forename: Claudio
authors.initials: C
authors.lastname: Toniolo
mesh_terms: D000596:Amino Acids / Q000138:chemical synthesis / Q000737:chemistry; D005998:Glycine / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D009842:Oligopeptides / Q000737:chemistry; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D000596:Amino Acids; D009842:Oligopeptides; D010455:Peptides; D005998:Glycine