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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N6—H1⋯N4i	0.98 (4)	1.93 (4)	2.891 (3)	165 (3)
N2—H2⋯N3ii	0.99 (3)	1.90 (4)	2.878 (3)	167 (3)

Symmetry codes: (i) ; (ii) .