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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O2i	0.89 (3)	2.08 (3)	2.918 (2)	155 (3)
N3—H3N⋯O1ii	0.85 (3)	2.38 (3)	3.148 (3)	151 (2)
N3—H3N⋯N2	0.85 (3)	2.33 (3)	2.681 (3)	105 (2)
C7—H7B⋯O4iii	0.98	2.55	3.475 (3)	158

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