Synthesis of N-phosphopeptides coupled by dichlorotriphenyl-phosphorane

Coupling of N-phosphoamino acids 2 and amino acid methyl esters by dichloro triphenylphosphorane 3 produced N-phosphopeptide methyl esters 5, which wer e sequentially hydrolyzed in triethylamine or dilute NaOH aqueous solution. The target products N-phosphodipeptides 6 were obtained in reasonable yiel ds and high purity after isolation using extraction method. The convenient and efficient approach could be generally used for synthesis of polypeptide s.