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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H41⋯O3i	0.88 (2)	1.88 (2)	2.7518 (18)	168 (3)
O4—H42⋯O2ii	0.87 (2)	1.81 (2)	2.640 (2)	158 (2)

Symmetry codes: (i) ; (ii) .