In order to visualize the inter­molecular inter­actions in the crystal of the title complex, a Hirshfeld surface (HS) analysis (Hirshfeld, 1977 ▸; Spackman & Jayatilaka, 2009 ▸) was carried out by using Crystal Explorer 17.5 (Turner et al., 2017 ▸). In the HS plotted over d norm (Fig. 3 ▸), the white surfaces indicate contacts with distances equal to the sum of van der Waals radii, and the red and blue colours indicate distances shorter (in close contact) or longer (distinct contact) than the van der Waals radii, respectively (Venkatesan et al., 2016 ▸). The bright-red spots appearing near SB-O1, SB-O4, NA-O5 and hydrogen atoms H21, H31, H32 and H61 indicate their role as the respective donors and acceptors in the dominant O—H⋯O and N—H⋯O hydrogen bonds; they also appear as blue and red regions, respectively, corresponding to positive and negative potentials on the HS mapped over electrostatic potential (Spackman et al., 2008 ▸; Jayatilaka et al., 2005 ▸) as shown in Fig. 4 ▸. The blue regions indicate the positive electrostatic potential (hydrogen-bond donors), while the red regions indicate the negative electrostatic potential (hydrogen-bond acceptors). The overall two-dimensional fingerprint plot and those delineated into H⋯O/O⋯H, H⋯H, H⋯C/C⋯H, H⋯N/N⋯H, O⋯C/C⋯O, O⋯O and N⋯C/C⋯N contacts (McKinnon et al., 2007 ▸) are illustrated in Fig. 5 ▸ a–h, respectively, together with their relative contributions to the Hirshfeld surface. The most important inter­action is H⋯O/O⋯H contributing 42.2% to the overall crystal packing, which is reflected in Fig. 5 ▸ b as a pair of spikes with the tip at d e + d i ∼1.63 Å. The short H⋯O/O⋯H contacts are masked by strong O—H⋯O hydrogen bonding in this plot. In the fingerprint plot delineated into H⋯H contacts (Fig. 5 ▸ c), the 25.7% contribution to the overall crystal packing is reflected as widely scattered points of high density due to the large hydrogen content of the mol­ecule. In the absence of C—H⋯π inter­actions in the crystal, the pair of characteristic wings resulting in the fingerprint plot delineated into H⋯C/C⋯H contacts with a 20.0% contribution to the HS, Fig. 5 ▸ d, and the pair of edges at d e + d i ∼2.58 Å result from short inter­atomic H⋯C/C⋯H contacts. The H⋯N/N⋯H (Fig. 5 ▸ e) and O⋯C/C⋯O (Fig. 5 ▸ f) contacts in the structure with 3.1% and 2.9% contributions to the HS have symmetrical distributions of points with the tips at d e + d i ∼2.8 Å and d e + d i ∼2.4 Å, arising from short inter­atomic H⋯N/N⋯H and O⋯C/C⋯O contacts, respectively. The O⋯O contacts assigned to short inter­atomic O⋯O contacts with a 1.6% contribution to the HS appear as an arrow-shaped distribution of points in Fig. 5 ▸ g, with the vertex at d e = d i ∼3.5 Å. Finally, the N⋯C/C⋯N contacts in the structure with a 1.6% contribution to the HS has a nearly symmetrical distribution of points, Fig. 5 ▸ h, with the scattered points of low density. The Hirshfeld surface representations with the function d norm plotted onto the surface are shown for the H⋯O/O⋯H, H⋯H, H⋯C/C⋯H, H⋯N/N⋯H and O⋯C/C⋯O inter­actions in Fig. 6 ▸ a–e, respectively.