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

Cg1 is the mid-point of the C3=C4 bond.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯N4A i	0.88	2.21	2.981 (4)	147
N2—H2⋯N3ii	0.88	2.09	2.966 (4)	172
C15A—H15A⋯O1iii	0.95	2.39	3.322 (4)	169
C12—H12⋯Cg1	0.95	2.85	3.290 (2)	109

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