Abstract: When N-(O,O-diisopropylphosphoryl)histidine(DIPP His)was incubated at 40℃ in water solutions for 90 h, homo dipeptides,tripeptides even tetra peptides(DIPP-His His His His and His His His His)were detected through FAB-MSand 13 CNMRanalysis.When DIPP-His was incubated with other amino acids in water solution, hetero di and tri peptides (DIPP His pro, DIPP His Asp Asp)were detected.WhenDIPP His was incubated with Gly Glv and Gly GlyOBu, hetero tripeptides(DIPP His Gly Gly and DIPP His Gly GlyOBu)were detected.Apentacoordinated phosphorous intramolecular mixed anhydride may be the activatlng intermediate.

Key words: Phosphohistidine, Peptides formation, Water solution