Syntheses of 4-[N-(tert-butoxycarbonyl)aminoacyloxymethyl]-3-nitrobenzoic acids for use in the liquid-phase peptide synthesis.
The syntheses of 4-(Boc-aminoacyloxymethyl)-3-nitrobenzoic acids are described. These compounds are suitable reagents for coupling to polyethylene glycol or its derivatives by the dicyclohexylcarbodiimide method to obtain 4-(Boc-aminoacyloxymethyl)-3-nitrobenzoyl-polyethylene glycol support. This is demonstrated by the reaction of the 4-carboxy-2-nitrobenzyl ester of Boc-alanine with glycylpolyethylene glycol in excellent yield. This synthetic route produces a much better coupling yield and an easier purification procedure in comparison with the original method in which Boc-amino acid cesium salts are allowed to react with 4-(bromomethyl)-3-nitrobenzoyl-polyethylene glycol.
D000596:Amino Acids / Q000138:chemical synthesis*; D004024:Dicyclohexylcarbodiimide; D005561:Formates / Q000138:chemical synthesis*; D005563:Formic Acid Esters / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D008722:Methods; D009579:Nitrobenzoates / Q000138:chemical synthesis; D009904:Optical Rotation; D010455:Peptides / Q000138:chemical synthesis*
D000596:Amino Acids; D005561:Formates; D005563:Formic Acid Esters; D007202:Indicators and Reagents; D009579:Nitrobenzoates; D010455:Peptides; C000345:t-butyloxycarbonyl group; D004024:Dicyclohexylcarbodiimide