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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N4—H4N⋯O1	0.915 (17)	2.023 (17)	2.8261 (13)	145.6 (14)
N4—H4N⋯O2	0.915 (17)	2.040 (17)	2.6497 (14)	122.8 (13)
N2—H2N⋯O6i	0.936 (18)	1.711 (18)	2.6464 (14)	177.4 (16)
O6—H6⋯O1	0.89 (2)	1.72 (2)	2.5863 (14)	167 (2)

Symmetry code: (i) .