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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2B⋯O3	0.860 (10)	1.95 (2)	2.631 (4)	135 (3)
O3—H3B⋯O1i	0.822 (10)	1.908 (15)	2.705 (4)	163 (4)
N1—H1B⋯O2ii	0.871 (10)	2.03 (2)	2.810 (4)	148 (4)

Symmetry codes: (i) ; (ii) .