N-benzhydryl-glycolamide: the first protecting group in peptide synthesis with a strong conformational bias.
We have synthesized and examined the preferred conformation of a set of N-benzhydryl-glycolamide esters from N(alpha)-protected (or N(alpha)-blocked) alpha-amino acids. Experiments were performed in CDCl(3) solution by Fourier transform infrared absorption and (1)H-NMR techniques, and in the crystalline state by x-ray diffraction. The results of our analysis strongly support the view that this type of N(alpha)-acylated alpha-aminoacyl esters has a marked tendency to fold into a beta-turn conformation, the nature of which is dictated by the structural propensity of the amino acid constituent at the i+1 position.
Crisma
Marco
M
Institute of Biomolecular Chemistry, Padova Unit, CNR, Department of Organic Chemistry, University of Padova, Italy. marco.crisma@unipd.it
Formaggio
Fernando
F
Ruzza
Paolo
P
Calderan
Andrea
A
Elardo
Stefano
S
Borin
Gianfranco
G
Toniolo
Claudio
C
D001559:Benzhydryl Compounds; D018360:Crystallography, X-Ray; D004121:Dimethyl Sulfoxide; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry*; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared
D001559:Benzhydryl Compounds; D007202:Indicators and Reagents; D010455:Peptides; D004121:Dimethyl Sulfoxide