Crystal structure of 8-(4-methylphenyl)-2 '-deoxyadenosine hemihydrate

In the asymmetric unit, equalling the unit cell (triclinic, P1, Z = 1), two molecules of the title compound, 8-(4-methylphenyl)-d-2'-deoxyadenosine, C17H19N5O3, are present, with distinct conformations of the two sugar moieties, together with one solvent water molecule. All three ribose O atoms are involved in hydrogen bonding and the crystal packing is largely determined by hydrogen-bonding or hydrogen-heteroatom interactions (O-H center dot center dot center dot O, O-H center dot center dot center dot N, N-H center dot center dot center dot O, C-H center dot center dot center dot O and C-H center dot center dot center dot N) with one independent molecule directly linked to four neighbouring molecules and the other molecule directly linked to six neighbouring molecules. The two independent molecules of the asymmetric unit display three weak intramolecular C-H-to-heteroatom contacts, two of which are very similar despite the different conformations of the deoxyribosyl moieties. The aromatic ring systems of both molecules are in proximity to each other and somehow aligned, though not coplanar. The absolute structures of the two molecules were assumed with reference to the reactant 8-bromo-D-2'-deoxyadenosine as they could not be determined crystallographically.