The crystal and molecular structure of the title compound, C12H11N5O1 · C2H4O2, has been elucidated at 298 K by a single crystal X-ray diffraction. The colorless crystals are monoclinic, space group P21/c, with unit cell dimensions a = 10.303(2) Å, b = 5.4863(8) Å, c = 26.209(3) Å, β = 91.18(2)°, Z = 4, Dc = 1.351 Mg m−3. The structure was solved by direct methods and refined by full-matrix least-squares procedure to final R = 0.046 for 1419 observed reflections (I > 2σ(I)). The structure is stabilized by intra- and intermolecular hydrogen bonds. An unusual decline in cytokinin activity of the present compound is most likely caused by the existence of hydrogen bond between the N6-side chain OH group and the N(1) purine atom [O(16)–H(16) … N(1) = 1.82(4) Å].