Crystal and molecular structure of 1,N6-ethenoadenosine hydrochloride

Abstract

The X-ray structure of 1,N6-ethenoadenosine hydrochloride, C12H14N5O4Cl, has been determined from three-dimensional diffractometer data and refined by full-matrix least-squares techniques. The crystals are monoclinic:P21 No. 14,a=6.1540(5),b=18.511(1),c=6.7412(4) A,β=112.602(5)°,andZ=2; finalR=0.045 for 2662 observed reflections. The crystal and molecular structure of ∈ Ado·HC1 is very similar to that of Ado·HC1. On the other hand, the dimensions and conformation of the ∈ Ado·H+ cation are drastically different from those of Et ∈ Ado·H+. The ∈ adenosine·H+ moiety is not planar but has an S shape. The ribose is 2′-endo-3′-exo puckered, with ag+ side chain; the glycosidic torsion angle is in theanti region. The structure contains a three-dimensional network of H bonds in which also C-H⋯A interactions seem to play an important role. There is no base stacking in the structure.