The effect of Mg and Ca on urea-catalyzed phosphorylation reactions.

When struvite (MgNHPO ⋅ 6HO) is heated with urea at 65-100°C, inorganic pyrophosphate is formed in good yield. Under similar conditions pyro-phosphate is formed much more slowly from ammonium phosphate or hydroxylapatite. The major products formed by the reaction of nucleotides with urea and either ammonium phosphate or hydroxylapatite are derivatives phosphorylated on the 2′ or 3′ position. With struvite, on the other hand, the main reaction is pyrophosphate bond formation. Yields of up to 25% of uridine diphosphate can be obtained at temperatures as low as 65°C. [ABSTRACT FROM AUTHOR]