Non-enzymic formation and rupture of phosphorus to nitrogen linkages in phosphoramido derivatives

Abstract

1. 1. Reactions of phosphoramidate with water and with heterocyclic bases containing the pyridine or imidazole ring are presented. Transfer of the phosphoryl group from phosphoramidate is shown to occur to imidazole, histidine, histamine, 1-phosphoimidazole, 1-phosphohistidine, and 1-phosphohistamine. 2. 2. Conditions for phosphorylation of insulin by phosphoramidate are described. 3. 3. 1,3-Diphosphoimidazole is formed not only by reaction between phosphoramidate and 1-phosphoimidazole, but also by the reaction of two molecules of 1-phosphoimidazole. Kinetically, a corresponding formation of 1,3-diphosphohistidine is indicated. 4. 4. Preparations of the calcium salts of phosphorylated imidazole derivatives are described. 5. 5. Reactions of 1,3-diphosphoimidazole with water and with nitrogenous bases are described. The reaction of 1,3-diphosphoimidazole with amines in aqueous solution provides a new method of phosphorylation. 6. 6. No intramolecular migration of the phosphoryl group from nitrogen to oxygen was observed in N-phosphorylated hydroxyamino compounds like ethanolamine and homoserine or in insulin. 7. 7. In the enzymic phosphorylation of adenosine diphosphate, phosphocreatine prepared with 1,3-diphosphoimidazole was active. Phosphoramidate and 1,3-diphosphoimidazole were inactive. 8. 8. The different phosphoryl transfers are discussed in relation to the structure of the phosphoryl donors and acceptors.