The reaction between hydroxylamine and cytosine derivatives

Abstract

In connection with the mutagenic activity of hydroxylamine, the reaction between hydroxylamine and cytosine (I) has been further studied. First-order rate constants are assigned to the processes leading simultaneously to N(4)-hydroxycytosine (II) and 6-hydroxyamino-5,6-dihydrocytosine (IV), and then to N(4)-hydroxy-6-hydroxyamino-5,6-dihydrocytosine (III), and to those relating to the equilibrium (II)⇌(III). Arate constant for the conversion of 5-hydroxymethylcytosine into its N(4)-hydroxy-derivative is also obtained; no evidence for the addition reaction is found in this case.