Nitrone protecting groups for enantiopure N-hydroxyamino acids: synthesis of N-terminal peptide hydroxylamines for chemoselective ligations
作者:S. Irene Medina、Jian Wu、Jeffrey W. Bode
DOI:10.1039/c004490c
日期:——
The synthesis of enantiopure N-benzylidene nitrones of N-hydroxy-α-amino acids and their incorporation using standard Fmoc-based peptide chemistry into solid-supported peptide chains is described. Deprotection and resin cleavage affords N-terminal peptide hydroxylamines, which are the key substrates for chemoselective ligations with C-terminal peptide α-ketoacids. This general route is applicable to
The invention relates to novel oxazinones designed to bind to the penicillin receptor, methods of synthesizing the compounds, and the use of the compounds as antibacterial agents. The compounds have the general formula (I)
Preferably the compounds have a carboxyethyl or a substituted carboxymethyl substituent at the 2-position and a hydroxyl group at the 5-position and have a molecular shape suitable for binding to and reacting with the active site of a pencillin-recognizing enzyme. The compounds are synthesized by condensing a carboxyl-protected N-hydroxy amino acid with a 3-hydroxyprotected-4-bromobutanoic acid to form a a doubly protected N-hydroxy N-acylamino acid, which is cyclized with an organic base to yield a doubly protected 1,2-oxazin-3-one. The protecting groups are then removed to provide an antibacterial agent.