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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O6i	0.90	1.92	2.767 (3)	156
N1—H1B⋯O2ii	0.90	2.15	2.940 (3)	147
N1—H1B⋯O2iii	0.90	2.39	3.039 (3)	129
O6—H6⋯O4iv	0.82	1.90	2.720 (3)	175

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