The conformation of 5-bromocytidine 5'-monophosphate in the title comp
ound, Na+.C9H11BrN3O8P-.1.25H2O, is anti, C(3')-endo and gauche-gauche
, similar to that in analogous non-halogenated nucleosides/nucleotides
. The Na ion coordinates directly with phosphate O atoms and base atom
s. Br is not involved in any stacking interaction.