X-ray evidence for metal-N-7 bonding in a hydrated manganese derivative of guanosine 5'-monophosphate.

Single-crystal X-ray studies of a manganese(II) derivative of guanosine 5'-monophosphate, [Mn(5'-GMP)(H(2)O)(5)],3H(2)O, have shown that it is isostructural with its nickel analogue. The manganese atom therefore is bonded to five water molecules with the remaining octahedral co-ordination site being occupied by N-7 of the nucleotide base. No direct metal-phosphate bonding is involved, but there are structure-stabilizing intramolecular hydrogen bonds between two phosphate oxygen atoms and co-ordinated water molecules.