STRUCTURE OF TRICHLORO(9-METHYLADENINIUM)ZINC(II) MONOHYDRATE

[ZnCl3(C6H8N5)].H2O, M(r) = 339.9, monoclinic, P2(1)/n, a = 6.334 (1), b = 14.204 (1), c = 14.215 (1) angstrom, beta = 100.72 (1)degrees, V = 1256.6 (5) angstrom3, Z = 4, D(x) = 1.796 (1) Mg m-3, lambda(Mo Kalpha) = 0.71073 angstrom, mu = 2.632 mm-1, F(000) = 680, T = 293 (1) K, R = 0.020, wR = 0.025 for 1594 observed reflections with I > 3 sigma(I). The Zn atom is coordinated to three Cl atoms and to the N(7) of the adenine molecule in a distorted tetrahedral arrangement. This indicates that for nucleic acids N(7) is a possible coordination site for bivalent metal ions. The adenine molecule, which is protonated at N(1), is significantly non-planar with a dihedral angle of 4.4 (9)degrees between the imidazole and the pyrimidine rings.