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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2N⋯N5i	0.90 (2)	2.01 (2)	2.9010 (16)	171 (1)
N4—H4A⋯N3ii	0.90 (2)	2.11 (2)	2.9971 (16)	172 (1)
N4—H4B⋯N1i	0.93 (2)	2.19 (2)	3.0264 (16)	151 (1)

Symmetry codes: (i) ; (ii) .