Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H21⋯O2i	0.82 (4)	2.09 (4)	2.864 (3)	156 (4)
N2—H22⋯O3ii	0.79 (4)	2.22 (4)	2.951 (3)	153 (4)
O4—H41⋯O2iii	0.86 (4)	1.77 (4)	2.612 (2)	165 (5)
O4—H42⋯O3iv	0.83 (4)	2.09 (4)	2.886 (2)	162 (3)
C9—H9⋯Cg1v	0.93	2.89	3.617 (3)	136

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) . Cg1 is the centroid of the C2–C7 ring.