Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4N⋯N3i	0.86	2.17	3.022 (3)	170
N9—H9N⋯N8ii	0.86	2.20	3.044 (3)	169

Symmetry codes: (i) ; (ii) .