Crystal structure, Hirshfeld surface analysis and anti­oxidant capacity of 2,2′-{(1E,1′E)-[1,2-phenyl­enebis(aza­nylyl­idene)]bis­(methanylyl­idene)}bis­(5-benz­yloxy)phenol

Ghichi, N.; Benboudiaf, A.; DJebli, Y.; Bensouici, C.; Merazig, H.

doi:10.1107/S2056989018005832

research communications

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 74| Part 5| May 2018| Pages 682-686

https://doi.org/10.1107/S2056989018005832

Open

access

Crystal structure, Hirshfeld surface analysis and antioxidant capacity of 2,2′-{(1E,1′E)-[1,2-phenylenebis(azanylylidene)]bis(methanylylidene)}bis(5-benzyloxy)phenol

Nadir Ghichi,^a ^* Ali Benboudiaf,^a Yacine DJebli,^b Chawki Bensouici ^c and Hocine Merazig ^a

^aUnit of Research CHEMS, University of Constantine1, Algeria, ^bLaboratory of Materials Chemistry, University of Constantine1, Algeria, and ^cBiotechnology Research Center, Constantine, Algeria
^*Correspondence e-mail: nadirgh82@hotmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 6 April 2018; accepted 15 April 2018; online 19 April 2018)

The whole molecule of the title Schiff base compound, C₃₄H₂₈N₂O₄, is generated by mirror symmetry, with the mirror bisecting the central benzene ring. It was synthesized via the condensation reaction of 1,2-diaminebenzene with 4-benzyloxy-2-hydroxybenzaldehyde. The molecule is V-shaped and there are two intramolecular O—H⋯N hydrogen bonds present forming S(6) ring motifs. The configuration about the C=N imine bonds is E. The central benzene ring makes dihedral angles of 41.9 (2) and 43.6 (2)° with the phenol ring and the outer benzyloxy ring, respectively. The latter two rings are inclined to each other by 84.4 (2)°. In the crystal, molecules are linked by C—H⋯π interactions, forming layers lying parallel to the ab plane. The Hirshfeld surface analysis and the two-dimensional fingerprint plots confirm the predominance of these interactions in the crystal structure. The antioxidant capacity of the compound was determined by the cupric reducing antioxidant capacity (CUPRAC) process.

Keywords: crystal structure; Schiff base; antioxidant capacity; CUPRAC; hydrogen bonding; C—H⋯π interactions; Hirshfeld surface analysis.

CCDC reference: 1837095

1. Chemical context

Schiff base derivatives are a biologically versatile class of compounds possessing diverse activities, such as anti-oxidant (Haribabu et al., 2015 , 2016 ), anti-inflammatory (Alam et al., 2012 ), antianxiety, antidepressant (Jubie et al., 2011 ), anti-tumour, antibacterial, and fungicidal properties (Refat et al., 2008 ; Kannan & Ramesh, 2006 ). Bis-bidentate Schiff base ligands have been studied extensively and used as building blocks in metallo-supramolecular chemistry (Birkedal & Pattison, 2006 ; Shahverdizadeh & Tiekink, 2011 ; Chu & Huang, 2007 ; Yoshida & Ichikawa, 1997 ; Kruger et al., 2001 ). The common structural feature of these compounds is the presence of an azomethine group, linked by a η methylene bridge, which can act as a hydrogen-bond acceptor. In view of this interest we have synthesized the title compound, (I), and report herein on its crystal structure. The ¹H NMR NMR spectrum reveals the presence of an imino group (N=CH) in the range δ = 8.5–8.7 p.p.m. The antioxidant capacity of the compound was determined by the cupric reducing antioxidant capacity (CUPRAC) process.

2. Structural commentary

The molecular structure of compound (I) is illustrated in Fig. 1. The asymmetric unit consists of half a molecule, with the whole molecule being generated by mirror symmetry. The mirror bisects the central benzene ring, viz. bonds C1—C1ⁱ and C3—C3ⁱ [symmetry code: (i) −x, y, z]. In the molecule there are two intramolecular O—H⋯N hydrogen bonds present (Table 1), which form S(6) ring motifs as shown in Fig. 1. The configuration of the C4=N1 imine bonds is E and the C4=N1 bond length is 1.278 (6) Å. The C3—N1=C4 bond angles are less than 120° [118.9 (4)°], and the imine group has a C3—N1—C4—C5 torsion angle of −176.8 (4)°. The molecule is V-shaped and the two arms are non-planar; the central benzene ring forms dihedral angles of 41.9 (2) and 43.6 (2)° with the phenol ring (C5-C10) and the outer benzyloxy ring (C12–C17), respectively. The latter two rings are almost normal to each other, with a dihedral angle of 84.4 (2)°.

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C5–C10 phenol ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O⋯N1	0.82	1.90	2.622 (5)	147
C2—H2⋯Cg2ⁱ	0.93	2.88	3.499 (5)	125
C13—H13⋯Cg2ⁱⁱ	0.93	2.60	3.493 (5)	161
Symmetry codes: (i) $[x, -y+1, z-{\script{1\over 2}}]$ ; (ii) $[x, -y, z+{\script{1\over 2}}]$ .

Figure 1
View of the molecular structure of compound (I)

, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. Unlabelled atoms are related to labelled atoms by the mirror symmetry code: (i) −x, y, z. The intramolecular O—H⋯N hydrogen bonds (see Table 1

) are shown as dashed lines.

3. Supramolecular features and Hirshfeld surface analysis

In the crystal of (I), molecules are linked by C—H⋯π interactions (Table 1), forming layers parallel to the (001) plane, as illustrated in Fig. 2.

Figure 2
Crystal packing of compound (I)

viewed along the c axis, with the O—H⋯N intramolecular hydrogen bonds and the C—H⋯π interactions (see Table 1

) illustrated as dashed lines.

The Hirshfeld surface analysis (Spackman & Jayatilaka, 2009 ) and the associated two-dimensional fingerprint plots (McKinnon et al., 2007 ) were performed with CrystalExplorer17 (Turner et al., 2017 ). The Hirshfeld surface of compound (I) mapped over d_norm is given in Fig. 3, and the fingerprint plots are given in Fig. 4. They reveal that the principal intermolecular interactions are H⋯H at 45.7% (Fig. 4b) and H⋯C/C⋯H at 34.6% (Fig. 4c), followed by the H⋯O/O⋯H interactions at 13.6% (Fig. 4d).

Figure 3
View of the Hirshfeld surface of (I)

mapped over d_norm.

Figure 4
The two-dimensional fingerprint plots of (I)

: (a) all interactions; (b) H⋯H; (c) H⋯C/C⋯H; (d) H⋯O/O⋯H.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.39, last update February 2018; Groom et al., 2016 ) for similar compounds yielded four hits. These compounds (see Fig. 5) include 5,5′-dihydroxy-2,2′-[o-phenylenebis(nitrilomethylene)]diphenol ethanol solvate (II) (CSD refcode HUVXUT; Soroceanu et al., 2013 ), 5,5′-dimethoxy-2,2′-[4,5-dimethyl-o-phenylenebis(nitrilomethylidyne)]diphenol (III) (KUSJIS; Kargar et al., 2010 ), 1,2-bis{[(2-hydroxy-4-methoxyphenyl)(phenyl)methylene]amino}benzene (IV) (SOXCIS; Lippe et al., 2009 ) and 5,5′-dimethoxy-2,2′-1,2-phenylenebis(nitrilomethylidyne)]diphenol (V) (XIFREK; Eltayeb et al., 2007 ). In all four compounds there are two intramolecular O—H⋯N hydrogen bonds present forming S(6) ring motifs.

Figure 5
Similar compounds to that of the title compound, (I)

, in the CSD; see Section 4, Database survey.

In (II) the phenol rings are inclined to the central benzene ring by 53.9 (3) and 4.0 (2)° and to each other by 49.9 (2)°. In (III) the corresponding dihedral angles are 48.12 (8), 21.44 (8) and 47.70 (8)°, while in (V) the corresponding dihedral angles are 58.29 (12), 2.20 (12) and 57.60 (12)°. In compound (IV), that possesses twofold rotational symmetry with the twofold axis bisecting the central benzene ring, the phenol rings are inclined to the central benzene ring by 82.30 (5)° and to each other by 63.76 (5)°. In the title compound, which possesses mirror symmetry, the corresponding dihedral angles are 41.9 (2) and 68.9 (2)°.

A search of the CSD for metal complexes of compounds similar to compound (I) gave over 30 hits. The ligands always coordinate in a tetradentate manner. For example, there were 13 hits for transition metal complexes of compound (II). The majority involve square-planar coordinated metal atoms, such as in complexes (5,5′-dihydroxy-2,2′-[o-phenylenebis(nitrilomethylidyne)]diphenolato)nickel(II) dihydrate (POFFOG; Fun et al., 2008 ) and (4,4′-{1,2-phenylenebis[(nitrilo-κN)methylylidene]}dibenzene-1,3-diolato-κO³)copper(II) methanol solvate (DUQBEX; Niu et al., 2010 ). For compound (V), five hits were found; they include three sixfold-coordinated tin complexes (DOSCOF, DOSDAS, DOSFOI; Muñoz-Flores et al., 2014 ) and two square-pyramidal manganese complexes (ODESEY, Ghaemi et al., 2016 ; XIYQOM, Eltayeb et al., 2008 ).

5. Antioxidant activity

The antioxidant activity profile of the synthesized compound (I) was determined by utilizing the copper(II)–neocuprine [Cu^II-Nc] (CUPRAC) method (Apak et al., 2004 ). The CUPRAC method (Fig. 6) (cupric ion reducing antioxidant capacity) is based on the follow-up of the decrease in the increased absorbance of the neocuproene (Nc), copper (Cu⁺²)Nc₂–Cu⁺² complex. Indeed, in the presence of an antioxidant agent, the copper–neocuproene complex is reduced and this reaction is quantified spectrophotometrically at a wavelength of 450 nm.

Figure 6
Reduction of the chromogenic complex of Cu⁺²–Nc

According to the cupric ion reducing antioxidant capacity assay, the title compound displayed activity with variable potency in all tested concentrations, because the percentage (%) inhibition in the CUPRAC assay is good [A_0.50 = 15.03 ± 1.50 for a 4 mg dosage, compared to the results for buthylated toluene (BHT) [A_0.50 = 8.97 ± 3.94], used as a positive control (see Table 2). Note: In CUPRAC antioxidant activity, the values expressed are the mean ± s.u.s of three parallel measurements (p < 0.05).

Table 2
Cupric ion reducing antioxidant capacity of compound (I)

	Percentage (%) Inhibition
	12.5 µg	25 µg	50 µg	100 µg	200 µg	400 µg	800 µg	A0.50 (μg ml⁻¹)
Compound (I)	0.39±0.01	0.59±0.01	0.91±0.03	1.42±0.02	1.84±0.36	3.12±0.25	4.29±0.11	15.03±1.50
BHT	1.41±0.03	2.22±0.05	2.42±0.02	2.50±0.01	2.56±0.05	2.86±0.07	3.38±0.13	8.97±3.94

6. Synthesis and crystallization

1,2-Diaminebenzene (0.027 g) and 4-benzyloxy-2-hydroxybenzaldehyde (0.1141 g) in ethanol (15 ml) were refluxed for 1 h, then the solvent was evaporated in vacuo. The residue was recrystallized from ethanol, yielding yellow block-like crystals of the title compound on slow evaporation of the solvent. The purity of the compound was characterized by its NMR spectrum (250 MHz, CDCl₃). The azomethine proton appears in the 8.5–8.7 p.p.m. range, while the imine bond is characterized in the ¹³C RMN spectrum with the imine C and OH signals in the range 162.23–163.34 p.p.m. ¹H NMR: δ = 6.5–7.6 (m, 12H; H-ar), δ = 13.7 (s, 1H; OH), δ = 5.1 (s, 1H; CH₂–O). ¹³C NMR: 70.15, 120.33, 127.30, 127.64, 128.26, 128.75, 142.32, 162.23, 163.33, 163.34.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. The hydroxyl H atom was located in a difference-Fourier map and initially freely refined. In the final cycles of refinements it was positioned geometrically (O—H = 0.82 Å) and refined as riding with U_iso(H) = 1.5U_eq(O). The C-bound H atoms were positioned geometrically (C–H = 0.93–0.97 Å) and refined as riding with U_iso(H) = 1.2U_eq(C).

Table 3
Experimental details

Crystal data
Chemical formula	C₃₄H₂₈N₂O₄
M_r	528.58
Crystal system, space group	Orthorhombic, Cmc2₁
Temperature (K)	293
a, b, c (Å)	35.297 (3), 9.3902 (6), 8.3603 (5)
V (Å³)	2771.0 (3)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.08
Crystal size (mm)	0.03 × 0.02 × 0.01

Data collection
Diffractometer	Bruker APEXII CCD
No. of measured, independent and observed [I > 2σ(I)] reflections	4493, 2516, 1691
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.053, 0.158, 1.02
No. of reflections	2516
No. of parameters	185
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.29, −0.24
Computer programs: APEX2 and SAINT (Bruker, 2011 ), SHELXT2017 (Sheldrick, 2015a ), SHELXL2017 (Sheldrick, 2015b ), SHELXTL (Sheldrick, 2008 ), Mercury (Macrae et al.2008 ) and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 1837095

Crystal structure: contains datablocks Global, I. DOI: https://doi.org/10.1107/S2056989018005832/su5438sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018005832/su5438Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989018005832/su5438Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SHELXT2017 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015b); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

2,2'-{(1E,1'E)-[1,2-Phenylenebis(azanylylidene)]bis(methanylylidene)}bis(5-benzyloxy)phenol top

Crystal data top

C₃₄H₂₈N₂O₄	F(000) = 1112
M_r = 528.58	D_x = 1.267 Mg m⁻³
Orthorhombic, Cmc2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2c -2	Cell parameters from 1621 reflections
a = 35.297 (3) Å	θ = 2.2–21.3°
b = 9.3902 (6) Å	µ = 0.08 mm⁻¹
c = 8.3603 (5) Å	T = 293 K
V = 2771.0 (3) Å³	Block, yellow
Z = 4	0.03 × 0.02 × 0.01 mm

Data collection top

Bruker APEXII CCD diffractometer	R_int = 0.042
Detector resolution: 18.4 pixels mm^-1	θ_max = 27.5°, θ_min = 3.7°
φ and ω scans	h = −45→40
4493 measured reflections	k = −12→5
2516 independent reflections	l = −10→6
1691 reflections with I > 2σ(I)

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.053	Hydrogen site location: mixed
wR(F²) = 0.158	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0817P)²] where P = (F_o² + 2F_c²)/3
2516 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.29 e Å⁻³
1 restraint	Δρ_min = −0.24 e Å⁻³

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.05052 (9)	0.2350 (3)	0.3234 (5)	0.0693 (13)
O2	0.15676 (8)	0.0288 (3)	0.5919 (4)	0.0546 (9)
N1	0.03881 (9)	0.5084 (4)	0.3640 (5)	0.0487 (10)
C1	0.01955 (13)	0.8879 (4)	0.2654 (7)	0.0639 (15)
C2	0.03890 (12)	0.7645 (4)	0.2985 (6)	0.0567 (14)
C3	0.01982 (11)	0.6379 (4)	0.3322 (5)	0.0481 (11)
C4	0.06841 (12)	0.5103 (4)	0.4519 (6)	0.0495 (14)
C5	0.09057 (11)	0.3828 (4)	0.4833 (5)	0.0454 (11)
C6	0.08042 (11)	0.2506 (4)	0.4207 (5)	0.0475 (11)
C7	0.10168 (11)	0.1285 (4)	0.4566 (5)	0.0488 (11)
C8	0.13349 (11)	0.1401 (4)	0.5523 (5)	0.0463 (12)
C9	0.14420 (12)	0.2710 (4)	0.6146 (6)	0.0560 (16)
C10	0.12269 (12)	0.3889 (4)	0.5813 (5)	0.0560 (16)
C11	0.14781 (12)	−0.1086 (4)	0.5260 (6)	0.0547 (16)
C12	0.17886 (11)	−0.2104 (4)	0.5695 (5)	0.0449 (11)
C13	0.17544 (12)	−0.2993 (4)	0.6998 (6)	0.0543 (16)
C14	0.20330 (16)	−0.3988 (4)	0.7345 (6)	0.0677 (17)
C15	0.23502 (14)	−0.4070 (5)	0.6404 (7)	0.0700 (19)
C16	0.23920 (14)	−0.3165 (6)	0.5124 (7)	0.0697 (17)
C17	0.21118 (13)	−0.2190 (5)	0.4765 (6)	0.0617 (17)
H1	0.03276	0.97121	0.24301	0.0770*
H1O	0.04038	0.31254	0.30933	0.1040*
H2	0.06524	0.76529	0.29851	0.0680*
H4	0.0777 (10)	0.604 (4)	0.509 (5)	0.041 (9)*
H7	0.09442	0.04030	0.41635	0.0580*
H9	0.16571	0.27872	0.67824	0.0670*
H10	0.12968	0.47594	0.62529	0.0670*
H11A	0.12385	−0.14214	0.56862	0.0660*
H11B	0.14557	−0.10203	0.41061	0.0660*
H13	0.15420	−0.29259	0.76516	0.0650*
H14	0.20047	−0.45974	0.82141	0.0810*
H15	0.25371	−0.47378	0.66311	0.0840*
H16	0.26095	−0.32099	0.44979	0.0840*
H17	0.21407	−0.15860	0.38915	0.0740*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0640 (19)	0.0400 (16)	0.104 (3)	0.0056 (14)	−0.0359 (19)	−0.0063 (17)
O2	0.0595 (17)	0.0386 (14)	0.0658 (17)	0.0080 (12)	−0.0166 (15)	−0.0028 (14)
N1	0.0416 (17)	0.0335 (16)	0.071 (2)	0.0021 (14)	0.0019 (18)	0.0024 (15)
C1	0.063 (3)	0.0317 (19)	0.097 (3)	−0.0042 (16)	−0.001 (3)	0.003 (2)
C2	0.047 (2)	0.041 (2)	0.082 (3)	−0.0048 (17)	−0.002 (2)	0.000 (2)
C3	0.049 (2)	0.0322 (18)	0.063 (2)	0.0022 (16)	0.002 (2)	−0.0028 (17)
C4	0.049 (2)	0.0345 (19)	0.065 (3)	0.0002 (17)	0.003 (2)	−0.0024 (18)
C5	0.042 (2)	0.0373 (19)	0.057 (2)	−0.0015 (16)	0.002 (2)	−0.0033 (18)
C6	0.042 (2)	0.0364 (19)	0.064 (2)	−0.0017 (16)	−0.008 (2)	−0.0015 (17)
C7	0.051 (2)	0.0365 (18)	0.059 (2)	−0.0007 (16)	−0.010 (2)	−0.0041 (19)
C8	0.047 (2)	0.039 (2)	0.053 (2)	0.0063 (16)	−0.0047 (19)	0.0005 (17)
C9	0.058 (3)	0.045 (2)	0.065 (3)	−0.0010 (18)	−0.017 (2)	−0.003 (2)
C10	0.060 (3)	0.039 (2)	0.069 (3)	−0.0035 (18)	−0.011 (2)	−0.006 (2)
C11	0.059 (3)	0.041 (2)	0.064 (3)	0.0043 (19)	−0.013 (2)	−0.0047 (19)
C12	0.043 (2)	0.0378 (19)	0.054 (2)	0.0001 (16)	−0.0069 (18)	−0.0056 (18)
C13	0.054 (3)	0.049 (2)	0.060 (3)	0.0042 (18)	−0.004 (2)	−0.001 (2)
C14	0.082 (3)	0.051 (3)	0.070 (3)	0.013 (2)	−0.021 (3)	0.005 (2)
C15	0.060 (3)	0.055 (3)	0.095 (4)	0.020 (2)	−0.023 (3)	−0.028 (3)
C16	0.053 (3)	0.075 (3)	0.081 (3)	0.006 (2)	0.001 (3)	−0.021 (3)
C17	0.062 (3)	0.057 (3)	0.066 (3)	−0.005 (2)	−0.002 (2)	−0.001 (2)

Geometric parameters (Å, º) top

O1—C6	1.341 (5)	C12—C13	1.378 (6)
O2—C8	1.370 (5)	C13—C14	1.387 (6)
O2—C11	1.438 (5)	C14—C15	1.371 (8)
N1—C3	1.414 (5)	C15—C16	1.374 (8)
N1—C4	1.278 (6)	C16—C17	1.381 (7)
O1—H1O	0.8200	C1—H1	0.9300
C1—C1ⁱ	1.380 (6)	C2—H2	0.9300
C1—C2	1.373 (6)	C4—H4	1.05 (4)
C2—C3	1.395 (5)	C7—H7	0.9300
C3—C3ⁱ	1.399 (5)	C9—H9	0.9300
C4—C5	1.454 (5)	C10—H10	0.9300
C5—C10	1.400 (6)	C11—H11A	0.9700
C5—C6	1.394 (5)	C11—H11B	0.9700
C6—C7	1.403 (5)	C13—H13	0.9300
C7—C8	1.383 (6)	C14—H14	0.9300
C8—C9	1.388 (6)	C15—H15	0.9300
C9—C10	1.371 (6)	C16—H16	0.9300
C11—C12	1.499 (6)	C17—H17	0.9300
C12—C17	1.383 (6)

C8—O2—C11	117.4 (3)	C12—C17—C16	120.5 (5)
C3—N1—C4	118.9 (4)	C2—C1—H1	120.00
C6—O1—H1O	109.00	C1ⁱ—C1—H1	120.00
C1ⁱ—C1—C2	119.8 (4)	C1—C2—H2	119.00
C1—C2—C3	121.3 (4)	C3—C2—H2	119.00
N1—C3—C3ⁱ	118.3 (3)	N1—C4—H4	122 (2)
C2—C3—C3ⁱ	118.9 (4)	C5—C4—H4	116 (2)
N1—C3—C2	122.8 (4)	C6—C7—H7	120.00
N1—C4—C5	122.2 (4)	C8—C7—H7	120.00
C4—C5—C10	120.5 (4)	C8—C9—H9	120.00
C6—C5—C10	117.7 (3)	C10—C9—H9	120.00
C4—C5—C6	121.8 (4)	C5—C10—H10	119.00
O1—C6—C7	117.5 (3)	C9—C10—H10	119.00
C5—C6—C7	120.7 (4)	O2—C11—H11A	110.00
O1—C6—C5	121.8 (3)	O2—C11—H11B	110.00
C6—C7—C8	119.6 (4)	C12—C11—H11A	110.00
O2—C8—C9	115.0 (4)	C12—C11—H11B	110.00
C7—C8—C9	120.5 (4)	H11A—C11—H11B	108.00
O2—C8—C7	124.5 (3)	C12—C13—H13	120.00
C8—C9—C10	119.2 (4)	C14—C13—H13	120.00
C5—C10—C9	122.3 (4)	C13—C14—H14	120.00
O2—C11—C12	108.6 (3)	C15—C14—H14	120.00
C11—C12—C13	120.9 (4)	C14—C15—H15	120.00
C13—C12—C17	118.8 (4)	C16—C15—H15	120.00
C11—C12—C17	120.3 (4)	C15—C16—H16	120.00
C12—C13—C14	120.8 (4)	C17—C16—H16	120.00
C13—C14—C15	119.8 (4)	C12—C17—H17	120.00
C14—C15—C16	120.0 (5)	C16—C17—H17	120.00
C15—C16—C17	120.2 (5)

C11—O2—C8—C7	1.5 (6)	C4—C5—C10—C9	179.6 (4)
C11—O2—C8—C9	−177.8 (4)	C6—C5—C10—C9	0.9 (6)
C8—O2—C11—C12	174.0 (3)	O1—C6—C7—C8	177.9 (4)
C4—N1—C3—C2	41.3 (6)	C5—C6—C7—C8	−1.4 (6)
C4—N1—C3—C3ⁱ	−139.8 (4)	C6—C7—C8—O2	−178.4 (4)
C3—N1—C4—C5	−176.8 (4)	C6—C7—C8—C9	0.9 (6)
C1ⁱ—C1—C2—C3	0.1 (8)	O2—C8—C9—C10	179.9 (4)
C2—C1—C1ⁱ—C2ⁱ	0.0 (9)	C7—C8—C9—C10	0.5 (7)
C1—C2—C3—N1	178.9 (5)	C8—C9—C10—C5	−1.4 (7)
C1—C2—C3—C3ⁱ	−0.1 (7)	O2—C11—C12—C13	96.8 (4)
N1—C3—C3ⁱ—N1ⁱ	0.0 (6)	O2—C11—C12—C17	−84.8 (5)
N1—C3—C3ⁱ—C2ⁱ	−179.0 (4)	C11—C12—C13—C14	176.4 (4)
C2—C3—C3ⁱ—N1ⁱ	179.0 (4)	C17—C12—C13—C14	−2.0 (6)
C2—C3—C3ⁱ—C2ⁱ	0.0 (6)	C11—C12—C17—C16	−177.4 (4)
N1—C4—C5—C6	−0.9 (7)	C13—C12—C17—C16	1.0 (7)
N1—C4—C5—C10	−179.5 (4)	C12—C13—C14—C15	1.4 (7)
C4—C5—C6—O1	2.6 (6)	C13—C14—C15—C16	0.2 (7)
C4—C5—C6—C7	−178.2 (4)	C14—C15—C16—C17	−1.2 (8)
C10—C5—C6—O1	−178.8 (4)	C15—C16—C17—C12	0.6 (8)
C10—C5—C6—C7	0.5 (6)

Symmetry code: (i) −x, y, z.

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C5–C10 phenol ring.

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O···N1	0.82	1.90	2.622 (5)	147
C2—H2···Cg2ⁱⁱ	0.93	2.88	3.499 (5)	125
C13—H13···Cg2ⁱⁱⁱ	0.93	2.60	3.493 (5)	161

Symmetry codes: (ii) x, −y+1, z−1/2; (iii) x, −y, z+1/2.

Cupric ion reducing antioxidant capacity of compound (I) top

				Percentage (%) Inhibition
	12.5 µg	25 µg	50 µg	100 µg	200 µg	400 µg	800 µg	A0.50 (µg ml^-1)
Compound (I)	0.39±0.01	0.59±0.01	0.91±0.03	1.42±0.02	1.84±0.36	3.12±0.25	4.29±0.11	15.03±1.50
BHT	1.41±0.03	2.22±0.05	2.42±0.02	2.50±0.01	2.56±0.05	2.86±0.07	3.38±0.13	8.97±3.94

Funding information

We are grateful to the Department of Higher Scientific Research and CHEMS Research Unit, University of Constantine1, Algeria, for funding this research project.

References

Alam, M. S., Choi, J.-H. & Lee, D.-U. (2012). Bioorg. Med. Chem. 20, 4103–4108. Web of Science CrossRef CAS Google Scholar
Apak, R., Güçlü, K., Özyürek, M. & Karademir, S. E. (2004). J. Agric. Food Chem. 52, 7970–7981. Web of Science CrossRef CAS Google Scholar
Birkedal, H. & Pattison, P. (2006). Acta Cryst. C62, o139–o141. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Bruker (2011). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsion, USA. Google Scholar
Chu, Z. & Huang, W. (2007). J. Mol. Struct. 837, 15–22. Web of Science CSD CrossRef CAS Google Scholar
Eltayeb, N. E., Teoh, S. G., Chantrapromma, S., Fun, H.-K. & Adnan, R. (2008). Acta Cryst. E64, m670–m671. CSD CrossRef IUCr Journals Google Scholar
Eltayeb, N. E., Teoh, S. G., Chantrapromma, S., Fun, H.-K. & Ibrahim, K. (2007). Acta Cryst. E63, o3094–o3095. Web of Science CSD CrossRef IUCr Journals Google Scholar
Fun, H.-K., Kia, R., Mirkhani, V. & Zargoshi, H. (2008). Acta Cryst. E64, m1181–m1182. Web of Science CSD CrossRef IUCr Journals Google Scholar
Ghaemi, A., Keyvani, B., Rayati, S., Zarei, S. & Notash, B. (2016). Zh. Strukt. Khim. (Russ. J. Struct. Chem.), 57, 1027–1030. CAS Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CSD CrossRef IUCr Journals Google Scholar
Haribabu, J., Subhashree, G. R., Saranya, S., Gomathi, K., Karvembu, R. & Gayathri, D. (2015). J. Mol. Struct. 1094, 281–291. Web of Science CSD CrossRef CAS Google Scholar
Haribabu, J., Subhashree, G. R., Saranya, S., Gomathi, K., Karvembu, R. & Gayathri, D. (2016). J. Mol. Struct. 1110, 185–195. Web of Science CSD CrossRef CAS Google Scholar
Jubie, S., Sikdar, P., Antony, S., Kalirajan, R., Gowramma, B., Gomathy, S. & Elango, K. (2011). Pak. J. Pharm. Sci. 24, 109–112. Web of Science CAS PubMed Google Scholar
Kannan, M. & Ramesh, R. (2006). Polyhedron, 25, 3095–3103. Web of Science CrossRef CAS Google Scholar
Kargar, H., Kia, R., Khan, I. U., Sahraei, A. & Aberoomand Azar, P. (2010). Acta Cryst. E66, o728. Web of Science CSD CrossRef IUCr Journals Google Scholar
Kruger, P. E., Martin, N. & Nieuwenhuyzen, M. (2001). J. Chem. Soc. Dalton Trans. pp. 1966–1970. Web of Science CSD CrossRef Google Scholar
Lippe, K., Gerlach, D., Kroke, E. & Wagler, J. (2009). Organometallics, 28, 621–629. CAS Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
McKinnon, J. J., Jayatilaka, D. & Spackman, M. A. (2007). Chem. Commun. pp. 3814–3816. Web of Science CrossRef Google Scholar
Muñoz-Flores, B. M., Santillán, R., Farfán, N., Álvarez-Venicio, V., Jiménez-Pérez, V. M., Rodríguez, M., Morales-Saavedra, O. G., Lacroix, P. G., Lepetit, C. & Nakatani, K. (2014). J. Organomet. Chem. 769, 64–71. Google Scholar
Niu, M., Fan, S., Liu, K., Cao, Z. & Wang, D. (2010). Acta Cryst. E66, m77. CSD CrossRef IUCr Journals Google Scholar
Refat, M. S., El-Korashy, S. A., Kumar, D. N. & Ahmed, A. S. (2008). Spectrochim. Acta Part A, 70, 898–906. Web of Science CrossRef Google Scholar
Shahverdizadeh, G. H. & Tiekink, E. R. T. (2011). Acta Cryst. E67, o798. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Soroceanu, A., Shova, S., Cazacu, M., Balan, I., Gorinchoy, N. & Turta, C. (2013). J. Chem. Crystallogr. 43, 310–318. CAS Google Scholar
Spackman, M. A. & Jayatilaka, D. (2009). CrystEngComm, 11, 19–32. Web of Science CrossRef CAS Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Turner, M. J., McKinnon, J. J., Wolff, S. K., Grimwood, D. J., Spackman, P. R., Jayatilaka, D. & Spackman, M. A. (2017). CrystalExplorer17. University of Western Australia. https://hirshfeldsurface.net Google Scholar
Yoshida, N. & Ichikawa, K. (1997). Chem. Commun. pp. 1091–1092. CSD CrossRef Web of Science Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.