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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯Br2	0.88	2.48	3.358 (2)	175
N4—H4A⋯Br2i	0.88	2.48	3.342 (2)	167
N6—H6D⋯Br2ii	0.88	2.53	3.351 (2)	155
N8—H8A⋯Br2iii	0.88	2.49	3.362 (2)	169

Symmetry codes: (i) ; (ii) ; (iii) .