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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯O1i	0.88	2.18	2.979 (2)	151
N6—H6⋯O1	0.88	2.14	2.875 (2)	140
C7—H7⋯Ni1	0.95	2.50	3.0831 (19)	120
C19—H19⋯Ni1	0.95	2.57	3.1480 (19)	120

Symmetry code: (i) .