Amino acid bromides: their N-protection and use in the synthesis of peptides with extremely difficult sequences.
N(alpha)-Protected alpha-amino acid bromides were easily generated in situ with 1-bromo-N,N-2-trimethyl-1-propenylamine from the corresponding amino acids under very mild conditions. o-Nbs and the azido moieties proved to be compatible with these overactivated halides and were successfully applied in difficult peptide bond formations. N-Deprotection methods and the total step-by-step solution synthesis of a peptide containing up to seven consecutive L-(alphaMe)Valine residues are also reported. The assembly of this homopeptide was achieved in a short time and in very high yields by the azido/bromide system in a single repetitive operation.
G. Ronzoni Institute for Chemical and Biochemical Research, via G. Colombo 81, 20133 Milano, Italy.
Alma
A
DalPozzo
Minghong
M
Ni
Laura
L
Muzi
Andrea
A
Caporale
Roberto
R
De Castiglione
Bernard
B
Kaptein
Quirinus B
QB
Broxterman
Fernando
F
Formaggio
D000596:Amino Acids / Q000737:chemistry*; D001965:Bromides / Q000737:chemistry*; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D020650:Combinatorial Chemistry Techniques; D006842:Hydrocarbons, Brominated / Q000737:chemistry; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis*; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
C472458:1-bromo-N,N-2-trimethyl-1-propenylamine; D000596:Amino Acids; D001965:Bromides; D006842:Hydrocarbons, Brominated; D010455:Peptides