research communications
Crystal structures and antioxidant capacity of (E)-5-benzyloxy-2-{[(4-chlorophenyl)imino]methyl}phenol and (E)-5-benzyloxy-2-({[2-(1H-indol-3-yl)ethyl]iminiumyl}methyl)phenolate
aUnite of Research CHEMS, University of Constantine 1, Algeria, bThe Centre of Research in Biotechnology, Constantine, Algeria, and cLaboratory of Material Chemistry, University of Constantine 1, Algeria
*Correspondence e-mail: nadirgh82@hotmail.com
The title Schiff base compounds, C20H16ClNO2 (I) and C24H22N2O2 (II), were synthesized via the condensation reaction of 2-amino-4-chlorophenol for (I), and 2-(2,3-dihydro-1H-indol-3-yl)ethan-1-amine for (II), with 4-benzyloxy-2-hydroxybenzaldehyde. In both compounds, the configuration about the C=N imine bond is E. Neither molecule is planar. In (I), the central benzene ring makes dihedral angles of 49.91 (12) and 53.52 (11)° with the outer phenyl and chlorophenyl rings, respectively. In (II), the central benzene ring makes dihedral angles of 89.59 (9) and 72.27 (7)°, respectively, with the outer phenyl ring and the mean plane of the indole ring system (r.m.s. deviation = 0.011 Å). In both compounds there is an intramolecular hydrogen bond forming an S(6) ring motif; an O—H⋯O hydrogen bond in (I), but a charge-assisted N+—H⋯O− hydrogen bond in (II). In the crystal of (I), molecules are linked by C—H⋯π interactions, forming slabs parallel to plane (001). In the crystal of (II), molecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers. The dimers are linked by C—H⋯O hydrogen bonds, C—H⋯π interactions and a weak N—H⋯π interaction, forming columns propagating along the a-axis direction. The antioxidant capacity of the synthesized compounds was determined by cupric reducing antioxidant capacity (CUPRAC) for compound (I) and by 2,2-picrylhydrazyl hydrate (DPPH) for compound (II).
1. Chemical context
RR′C=NR′′ exhibit a wide structural diversity and have found a wide range of applications (Jia & Li, 2015). 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). They can be used as potential materials for optical memory and switch devices (Zhao et al., 2007). Besides their biological applications, many also reversibly bind with oxygen, coordinate with and show fluorescent variability with metals, exhibiting photo-chromism and/or thermochromism, and have been used as catalysts, pigments and dyes, corrosion inhibitors, polymer stabilizers, or precursors in the formation of nanoparticles (Gupta & Sutar, 2008; Gupta et al., 2009; Mishra et al., 2012). The common structural feature of these compounds is the presence of an azomethine group linked by an η-methylene bridge, which can act as hydrogen-bond acceptors. In view of this interest we have synthesized the title compounds, (I) and (II), and report herein on their crystal structures. The 1H NMR spectra revealed the presence of an imino group (N=CH) in the range δ = 8.5–8.6 p.p.m. Cupric reducing antioxidant capacity (CUPRAC) of (I) was estimated, and the antioxidant capacity of compound (II) was determined by in vitro 2,2-diphenyl-1-picrylhydrazil hydrate (DPPH) radical scavenging.
of the general type1.1. Structural commentary
The molecular structures of compounds (I) and (II), illustrated in Figs. 1 and 2, respectively, may be influenced by intramolecular hydrogen bonds; O—H⋯N in (I) and N+—H⋯O− in (II) (see Tables 1 and 2). These hydrogen bonds form S(6) ring motifs as shown in Figs. 1 and 2. In compound (II), the N atom is protonated (see Section 6, Refinement) and the C1—O13 (C—O−) bond length is 1.281 (2) Å, compared to the C9—O1 (C—OH) bond length of 1.343 (3) Å in (I). The configuration of the C=N imine bond is E in both compounds and the C=N bond lengths are 1.286 (3) Å for C7=N1 in (I) and 1.297 (3) Å for C11=N1 in (II). Neither molecule is planar: in (I), the central benzene ring (C8–C13) is inclined to the two outer benzene rings (C1–C6 and C15–C20) by 53.52 (11) and 49.91 (12)°, respectively, while in (II) the central benzene ring (C12–C17) makes dihedral angles of 89.59 (9) and 72.27 (7)°, respectively, with outer benzene ring (C19–C24) and the mean plane of the indole ring system (N2/C1–C8; r.m.s. deviation = 0.011 Å).
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2. Supramolecular features
In the crystal structures of both compounds C—H⋯π interactions predominate; see Table 1 for details concerning compound (I), and Table 2 for details concerning compound (II). In the crystal of (I), molecules are linked by C—H⋯π interactions, forming slabs lying parallel to (001), as illustrated in Fig. 3. In the crystal of (II), molecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers. The dimers are linked by C—H⋯O hydrogen bonds and C—H⋯π interactions, and a weak N—H⋯π interaction, forming columns propagating along the a-axis direction. The different hydrogen bonds and X—H⋯π (X = C, N) interactions are illustrated in Fig. 4, and the overall crystal packing is illustrated in Fig. 5. There are no other significant intermolecular contacts present in either crystal structure.
3. Database survey
The structures of et al., 2010). A search of the Cambridge Structural Database (Version 5.38, update May 2017; Groom et al., 2016) for substituted by a phenol group gave over 900 hits. Of these only three compounds with a benzyloxyphenol group resemble the title compounds. They include, (Z)-3-benzyloxy-6-[(2-hydroxyphenylamino)methylene]cyclohexa-2,4-dienone (KOSCUS; Ghichi et al., 2014a), (E)-5-benzyloxy-2-[(4-nitrophenyl)carbonoimidoyl]phenol (RUTQOO; Ghichi et al., 2015) and 5-benzyloxy-2-{[(2-hydroxy-5-methylphenyl)iminio]methyl}phenolate (WOJBEE; Ghichi et al., 2014b). In RUTQOO there is an intramolecular O—H⋯O hydrogen bond, as in compound (I). In KOSCUS and WOJBEE there are intramolecular charge-assisted N+-H⋯O− hydrogen bonds, as observed for compound (II).
derived from hydroxyaryl have recently been the subject of a general survey, in which a number of structural errors, often involving misplaced H atoms, were pointed out (Blagus4. Antioxidant activity
The antioxidant activity profile of the synthesized compound (I) was determined by utilizing the copper(II)–neocuprine (CuII–Nc) (CUPRAC) method (Apak et al., 2004). The CUPRAC method (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.
The current results indicate that Schiff base compound (I) has a low cupric ion reducing antioxidant capacity, because the absorbance in the CUPRAC assay is large (A0.50 > 100) for a 4 mg dosage (see Table 3). The current results indicate that the Schiff base compound (II), has a low free-radical scavenging activity (Blois, 1958), because the percentage inhibition in the DPPH assay is large (IC50 > 100) for a 1 mg dosage, by comparison with buthylated toluene (BHT) IC50 = 22.32 ±1.19, used as a positive control (see Table 3).
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Note: Compound (I): the activity is cupric ion reducing antioxidant capacity (CUPRAC) with the BHT (positive control). Compound (II): the BHT positive control or standard reference is different for each antioxidant activity test (percentage inhibition).
5. Synthesis and crystallization
2-Amino-4-chlorophenol (1 equiv.) and 4-benzyloxy-2-hydroxybenzaldehyde (1 equiv.) in ethanol (15 ml) were refluxed for 1 h. On completion of the reaction (monitored by thin layer chromatography), the solvent was evaporated in vacuo. The residue was recrystallized from methanol, yielding green block-like crystals of (I) on slow evaporation of the solvent. The purity of the compound was characterized by its NMR spectrum (250 MHz, CDCl3). In the 1H NMR spectrum, the azomethine proton appears in the 8.5–8.6 p.p.m. range, while the imine bond is characterized in the 13C MNR spectrum with the imine C signal in the 158–162 p.p.m. range. 1H NMR: δ 6.5–7.6 (m, 12H; H-ar), 13.8–14.0 (s, 1H; OH). 13C NMR: 70.22, 127.6, 128.8, 129.5 133.8, 136.2, 147.1.
2-(2,3-Dihydro-1H-indol-3-yl)ethan-1-amine (1 equiv.) and 4-benzyloxy-2-hydroxybenzaldehyde (1 equiv.) in methanol (15 ml) were refluxed for 1 h. On completion of the reaction (monitored by thin layer chromatography), the solvent was evaporated in vacuo and the residue recrystallized from methanol, yielding orange block-like crystals of (II) on slow evaporation of the solvent. In the 1H NMR spectrum, the azomethine proton appears in the 8.5–8.6 p.p.m. range, while the imine bond is characterized in the 13C NMR spectrum with the imine C signal in the 163.3–168.4 p.p.m. range. 1H NMR: δ 6.5–7.7 (m, 14H; H-ar), 13.8–14.0 (s, 1H; OH). 13C NMR: 56.9, 128.2, 128.7, 132.9, 136.4, 163.3.
6. Refinement
Crystal data, data collection and structure . In compound (I), the hydroxyl H atom was located in a difference-Fourier map and initially freely refined. In the final cycles of it was positioned geometrically (O—H = 0.82 Å) and refined with Uiso(H)= 1.5Ueq(O). In compound (II), an H atom was located in a difference-Fourier map close to atom N1 of the C11=N1 bond, and was freely refined, as was the indole NH H atom. For both compounds, the C-bound H atoms were positioned geometrically (C—H = 0.93–0.97Å) and refined as riding with Uiso(H) = 1.2Ueq(C).
details are summarized in Table 4
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Supporting information
https://doi.org/10.1107/S2056989018003687/su5426sup1.cif
contains datablocks global, I, II. DOI:Supporting information file. DOI: https://doi.org/10.1107/S2056989018003687/su5426Isup2.cml
For both structures, data collection: APEX2 (Bruker, 2012); cell
SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008). Program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015) for (I); SHELXL2014 (Sheldrick, 2015) for (II). For both structures, 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).C20H16ClNO2 | F(000) = 704 |
Mr = 337.79 | Dx = 1.369 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 6.056 (2) Å | Cell parameters from 2596 reflections |
b = 7.363 (3) Å | θ = 3.0–22.7° |
c = 36.761 (12) Å | µ = 0.25 mm−1 |
β = 91.30 (2)° | T = 293 K |
V = 1638.6 (10) Å3 | Block, green |
Z = 4 | 0.03 × 0.02 × 0.01 mm |
Bruker APEXII CCD diffractometer | Rint = 0.053 |
Detector resolution: 18.4 pixels mm-1 | θmax = 26.0°, θmin = 2.2° |
φ and ω scans | h = −7→6 |
13108 measured reflections | k = −9→9 |
3161 independent reflections | l = −45→45 |
2066 reflections with I > 2σ(I) |
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) = 0.153 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0611P)2 + 0.6069P] where P = (Fo2 + 2Fc2)/3 |
3161 reflections | (Δ/σ)max < 0.001 |
221 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.22 e Å−3 |
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 |
x | y | z | Uiso*/Ueq | ||
Cl1 | 1.14818 (15) | 0.25490 (13) | 0.48315 (2) | 0.0818 (3) | |
O1 | 0.2926 (3) | 0.2500 (3) | 0.30360 (5) | 0.0557 (7) | |
O2 | 0.3778 (3) | 0.3501 (2) | 0.17647 (4) | 0.0492 (6) | |
N1 | 0.6324 (3) | 0.3275 (3) | 0.34598 (5) | 0.0424 (7) | |
C1 | 0.7583 (4) | 0.3110 (3) | 0.37880 (6) | 0.0397 (8) | |
C2 | 0.9632 (4) | 0.2267 (3) | 0.37907 (7) | 0.0436 (8) | |
C3 | 1.0823 (4) | 0.2078 (3) | 0.41147 (7) | 0.0480 (8) | |
C4 | 0.9972 (5) | 0.2739 (4) | 0.44320 (7) | 0.0504 (9) | |
C5 | 0.7914 (4) | 0.3564 (4) | 0.44332 (7) | 0.0514 (9) | |
C6 | 0.6721 (4) | 0.3727 (3) | 0.41101 (6) | 0.0464 (8) | |
C7 | 0.7282 (4) | 0.3864 (3) | 0.31744 (6) | 0.0411 (8) | |
C8 | 0.6226 (4) | 0.3874 (3) | 0.28193 (6) | 0.0367 (7) | |
C9 | 0.4121 (4) | 0.3121 (3) | 0.27590 (6) | 0.0389 (7) | |
C10 | 0.3232 (4) | 0.2973 (3) | 0.24089 (6) | 0.0402 (8) | |
C11 | 0.4436 (4) | 0.3603 (3) | 0.21186 (6) | 0.0393 (8) | |
C12 | 0.6490 (4) | 0.4408 (3) | 0.21739 (6) | 0.0435 (8) | |
C13 | 0.7361 (4) | 0.4520 (3) | 0.25213 (6) | 0.0445 (8) | |
C14 | 0.1774 (4) | 0.2582 (4) | 0.16730 (7) | 0.0530 (9) | |
C15 | 0.1428 (4) | 0.2742 (3) | 0.12690 (6) | 0.0440 (8) | |
C16 | −0.0498 (4) | 0.3482 (4) | 0.11281 (7) | 0.0538 (9) | |
C17 | −0.0834 (5) | 0.3639 (4) | 0.07556 (8) | 0.0638 (11) | |
C18 | 0.0762 (5) | 0.3076 (4) | 0.05245 (7) | 0.0613 (10) | |
C19 | 0.2689 (5) | 0.2336 (4) | 0.06624 (8) | 0.0597 (10) | |
C20 | 0.3032 (4) | 0.2173 (4) | 0.10328 (7) | 0.0517 (9) | |
H1O | 0.36110 | 0.26625 | 0.32283 | 0.0830* | |
H2 | 1.02053 | 0.18292 | 0.35751 | 0.0520* | |
H3 | 1.21931 | 0.15070 | 0.41176 | 0.0580* | |
H5 | 0.73435 | 0.40013 | 0.46490 | 0.0620* | |
H6 | 0.53266 | 0.42571 | 0.41093 | 0.0560* | |
H7 | 0.889 (4) | 0.431 (3) | 0.3166 (6) | 0.055 (7)* | |
H10 | 0.18449 | 0.24578 | 0.23697 | 0.0480* | |
H12 | 0.72641 | 0.48643 | 0.19784 | 0.0520* | |
H13 | 0.87466 | 0.50422 | 0.25581 | 0.0530* | |
H14A | 0.05497 | 0.31303 | 0.17984 | 0.0640* | |
H14B | 0.18748 | 0.13143 | 0.17434 | 0.0640* | |
H16 | −0.15821 | 0.38799 | 0.12846 | 0.0650* | |
H17 | −0.21464 | 0.41268 | 0.06628 | 0.0760* | |
H18 | 0.05454 | 0.31939 | 0.02744 | 0.0730* | |
H19 | 0.37694 | 0.19433 | 0.05046 | 0.0720* | |
H20 | 0.43446 | 0.16793 | 0.11241 | 0.0620* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0886 (6) | 0.1109 (7) | 0.0449 (5) | 0.0212 (5) | −0.0232 (4) | −0.0042 (4) |
O1 | 0.0456 (10) | 0.0844 (14) | 0.0369 (10) | −0.0174 (9) | −0.0005 (7) | 0.0024 (9) |
O2 | 0.0542 (10) | 0.0571 (11) | 0.0359 (10) | −0.0125 (9) | −0.0058 (8) | 0.0028 (8) |
N1 | 0.0414 (11) | 0.0466 (12) | 0.0390 (12) | −0.0013 (9) | −0.0041 (9) | −0.0028 (9) |
C1 | 0.0422 (13) | 0.0400 (13) | 0.0367 (13) | −0.0024 (10) | −0.0045 (10) | 0.0001 (10) |
C2 | 0.0442 (13) | 0.0491 (15) | 0.0374 (13) | 0.0005 (11) | −0.0001 (10) | −0.0041 (11) |
C3 | 0.0438 (13) | 0.0526 (16) | 0.0474 (15) | 0.0030 (12) | −0.0018 (11) | −0.0024 (12) |
C4 | 0.0576 (16) | 0.0536 (16) | 0.0396 (14) | 0.0001 (13) | −0.0095 (12) | 0.0003 (12) |
C5 | 0.0613 (16) | 0.0562 (17) | 0.0368 (14) | 0.0057 (13) | 0.0048 (12) | −0.0068 (12) |
C6 | 0.0484 (14) | 0.0505 (15) | 0.0402 (14) | 0.0064 (12) | 0.0016 (11) | −0.0051 (11) |
C7 | 0.0430 (13) | 0.0366 (13) | 0.0437 (14) | −0.0017 (11) | −0.0018 (11) | −0.0021 (11) |
C8 | 0.0380 (12) | 0.0356 (12) | 0.0364 (13) | 0.0008 (10) | −0.0034 (10) | −0.0024 (10) |
C9 | 0.0382 (12) | 0.0406 (13) | 0.0379 (13) | 0.0004 (10) | 0.0032 (10) | 0.0003 (10) |
C10 | 0.0373 (12) | 0.0433 (14) | 0.0398 (13) | −0.0020 (10) | −0.0051 (10) | −0.0016 (11) |
C11 | 0.0465 (13) | 0.0358 (13) | 0.0354 (13) | 0.0021 (11) | −0.0036 (10) | 0.0010 (10) |
C12 | 0.0463 (13) | 0.0440 (14) | 0.0403 (14) | −0.0076 (11) | 0.0013 (11) | 0.0038 (11) |
C13 | 0.0423 (13) | 0.0447 (14) | 0.0464 (15) | −0.0094 (11) | −0.0026 (11) | 0.0024 (11) |
C14 | 0.0505 (15) | 0.0669 (18) | 0.0413 (14) | −0.0079 (13) | −0.0051 (11) | 0.0009 (12) |
C15 | 0.0474 (14) | 0.0449 (14) | 0.0392 (14) | −0.0025 (11) | −0.0070 (11) | 0.0000 (11) |
C16 | 0.0528 (15) | 0.0557 (17) | 0.0527 (17) | 0.0055 (13) | −0.0036 (12) | −0.0050 (13) |
C17 | 0.0638 (18) | 0.0645 (19) | 0.062 (2) | 0.0034 (15) | −0.0239 (15) | 0.0037 (15) |
C18 | 0.077 (2) | 0.0672 (19) | 0.0389 (15) | −0.0091 (16) | −0.0153 (14) | 0.0024 (14) |
C19 | 0.0669 (18) | 0.0667 (19) | 0.0459 (16) | −0.0072 (15) | 0.0083 (13) | −0.0092 (14) |
C20 | 0.0486 (14) | 0.0564 (17) | 0.0497 (16) | 0.0035 (12) | −0.0049 (12) | 0.0003 (13) |
Cl1—C4 | 1.718 (3) | C15—C20 | 1.383 (3) |
O1—C9 | 1.343 (3) | C15—C16 | 1.378 (4) |
O2—C11 | 1.354 (3) | C16—C17 | 1.385 (4) |
O2—C14 | 1.423 (3) | C17—C18 | 1.366 (4) |
N1—C1 | 1.418 (3) | C18—C19 | 1.374 (4) |
N1—C7 | 1.286 (3) | C19—C20 | 1.378 (4) |
O1—H1O | 0.8200 | C2—H2 | 0.9300 |
C1—C2 | 1.387 (3) | C3—H3 | 0.9300 |
C1—C6 | 1.382 (3) | C5—H5 | 0.9300 |
C2—C3 | 1.385 (4) | C6—H6 | 0.9300 |
C3—C4 | 1.375 (4) | C7—H7 | 1.03 (2) |
C4—C5 | 1.387 (4) | C10—H10 | 0.9300 |
C5—C6 | 1.381 (3) | C12—H12 | 0.9300 |
C7—C8 | 1.441 (3) | C13—H13 | 0.9300 |
C8—C13 | 1.390 (3) | C14—H14A | 0.9700 |
C8—C9 | 1.403 (3) | C14—H14B | 0.9700 |
C9—C10 | 1.388 (3) | C16—H16 | 0.9300 |
C10—C11 | 1.386 (3) | C17—H17 | 0.9300 |
C11—C12 | 1.389 (3) | C18—H18 | 0.9300 |
C12—C13 | 1.373 (3) | C19—H19 | 0.9300 |
C14—C15 | 1.500 (3) | C20—H20 | 0.9300 |
C11—O2—C14 | 118.99 (18) | C18—C19—C20 | 120.5 (3) |
C1—N1—C7 | 118.7 (2) | C15—C20—C19 | 120.1 (2) |
C9—O1—H1O | 109.00 | C1—C2—H2 | 120.00 |
N1—C1—C2 | 120.5 (2) | C3—C2—H2 | 120.00 |
C2—C1—C6 | 119.8 (2) | C2—C3—H3 | 120.00 |
N1—C1—C6 | 119.7 (2) | C4—C3—H3 | 120.00 |
C1—C2—C3 | 120.0 (2) | C4—C5—H5 | 120.00 |
C2—C3—C4 | 119.7 (2) | C6—C5—H5 | 120.00 |
Cl1—C4—C3 | 119.6 (2) | C1—C6—H6 | 120.00 |
Cl1—C4—C5 | 119.6 (2) | C5—C6—H6 | 120.00 |
C3—C4—C5 | 120.8 (2) | N1—C7—H7 | 125.3 (12) |
C4—C5—C6 | 119.2 (2) | C8—C7—H7 | 111.9 (12) |
C1—C6—C5 | 120.5 (2) | C9—C10—H10 | 120.00 |
N1—C7—C8 | 122.8 (2) | C11—C10—H10 | 120.00 |
C7—C8—C13 | 119.9 (2) | C11—C12—H12 | 120.00 |
C9—C8—C13 | 118.3 (2) | C13—C12—H12 | 120.00 |
C7—C8—C9 | 121.6 (2) | C8—C13—H13 | 119.00 |
O1—C9—C10 | 118.2 (2) | C12—C13—H13 | 119.00 |
C8—C9—C10 | 120.6 (2) | O2—C14—H14A | 110.00 |
O1—C9—C8 | 121.2 (2) | O2—C14—H14B | 110.00 |
C9—C10—C11 | 119.2 (2) | C15—C14—H14A | 110.00 |
O2—C11—C12 | 114.0 (2) | C15—C14—H14B | 110.00 |
C10—C11—C12 | 121.0 (2) | H14A—C14—H14B | 109.00 |
O2—C11—C10 | 124.9 (2) | C15—C16—H16 | 120.00 |
C11—C12—C13 | 119.1 (2) | C17—C16—H16 | 120.00 |
C8—C13—C12 | 121.7 (2) | C16—C17—H17 | 120.00 |
O2—C14—C15 | 107.2 (2) | C18—C17—H17 | 120.00 |
C14—C15—C16 | 120.1 (2) | C17—C18—H18 | 120.00 |
C16—C15—C20 | 119.0 (2) | C19—C18—H18 | 120.00 |
C14—C15—C20 | 120.9 (2) | C18—C19—H19 | 120.00 |
C15—C16—C17 | 120.6 (2) | C20—C19—H19 | 120.00 |
C16—C17—C18 | 120.0 (3) | C15—C20—H20 | 120.00 |
C17—C18—C19 | 119.9 (3) | C19—C20—H20 | 120.00 |
C14—O2—C11—C10 | −4.3 (3) | C13—C8—C9—C10 | 2.1 (3) |
C14—O2—C11—C12 | 175.4 (2) | C7—C8—C13—C12 | 174.2 (2) |
C11—O2—C14—C15 | 178.00 (19) | C9—C8—C13—C12 | −1.1 (3) |
C7—N1—C1—C2 | −47.9 (3) | O1—C9—C10—C11 | −179.9 (2) |
C7—N1—C1—C6 | 134.8 (2) | C8—C9—C10—C11 | −0.9 (3) |
C1—N1—C7—C8 | 172.3 (2) | C9—C10—C11—O2 | 178.4 (2) |
N1—C1—C2—C3 | −178.5 (2) | C9—C10—C11—C12 | −1.3 (3) |
C6—C1—C2—C3 | −1.2 (3) | O2—C11—C12—C13 | −177.5 (2) |
N1—C1—C6—C5 | 179.4 (2) | C10—C11—C12—C13 | 2.2 (3) |
C2—C1—C6—C5 | 2.1 (4) | C11—C12—C13—C8 | −1.0 (3) |
C1—C2—C3—C4 | −0.4 (4) | O2—C14—C15—C16 | −124.0 (2) |
C2—C3—C4—Cl1 | −178.50 (19) | O2—C14—C15—C20 | 55.3 (3) |
C2—C3—C4—C5 | 1.2 (4) | C14—C15—C16—C17 | 179.9 (3) |
Cl1—C4—C5—C6 | 179.4 (2) | C20—C15—C16—C17 | 0.6 (4) |
C3—C4—C5—C6 | −0.4 (4) | C14—C15—C20—C19 | −179.8 (3) |
C4—C5—C6—C1 | −1.3 (4) | C16—C15—C20—C19 | −0.5 (4) |
N1—C7—C8—C9 | −4.4 (4) | C15—C16—C17—C18 | −0.7 (4) |
N1—C7—C8—C13 | −179.6 (2) | C16—C17—C18—C19 | 0.7 (4) |
C7—C8—C9—O1 | 5.8 (3) | C17—C18—C19—C20 | −0.6 (5) |
C7—C8—C9—C10 | −173.2 (2) | C18—C19—C20—C15 | 0.5 (4) |
C13—C8—C9—O1 | −178.9 (2) |
Cg2 and Cg3 are the centroids of rings C8–C13 and C15–C20, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O···N1 | 0.82 | 1.89 | 2.616 (3) | 147 |
C3—H3···Cg3i | 0.93 | 2.85 | 3.593 (3) | 138 |
C6—H6···Cg3ii | 0.93 | 2.82 | 3.520 (3) | 133 |
C13—H13···Cg2iii | 0.93 | 2.79 | 3.419 (3) | 126 |
Symmetry codes: (i) −x+3/2, y−1/2, −z+1/2; (ii) −x+1/2, y+1/2, −z+1/2; (iii) −x+3/2, y+1/2, −z+1/2. |
C24H22N2O2 | F(000) = 784 |
Mr = 370.43 | Dx = 1.307 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 5.5265 (6) Å | Cell parameters from 2857 reflections |
b = 20.1714 (19) Å | θ = 3.2–23.1° |
c = 17.027 (2) Å | µ = 0.08 mm−1 |
β = 97.216 (5)° | T = 293 K |
V = 1883.1 (4) Å3 | Block, orange |
Z = 4 | 0.03 × 0.02 × 0.01 mm |
Bruker APEXII CCD diffractometer | Rint = 0.053 |
Detector resolution: 18.4 pixels mm-1 | θmax = 27.5°, θmin = 3.7° |
φ and ω scans | h = −6→7 |
17491 measured reflections | k = −20→26 |
4255 independent reflections | l = −22→21 |
2304 reflections with I > 2σ(I) |
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)] = 0.047 | Hydrogen site location: mixed |
wR(F2) = 0.124 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.054P)2] where P = (Fo2 + 2Fc2)/3 |
4255 reflections | (Δ/σ)max < 0.001 |
265 parameters | Δρmax = 0.14 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
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 |
x | y | z | Uiso*/Ueq | ||
O1 | 0.4706 (2) | −0.02601 (6) | 0.07995 (7) | 0.0650 (5) | |
O2 | 0.2598 (2) | −0.07547 (6) | 0.33695 (7) | 0.0583 (4) | |
N1 | 0.8488 (3) | 0.05404 (7) | 0.07254 (10) | 0.0556 (6) | |
N2 | 1.3886 (3) | 0.23680 (8) | −0.09864 (10) | 0.0562 (6) | |
C1 | 1.0855 (3) | 0.20232 (8) | −0.03230 (10) | 0.0472 (6) | |
C2 | 1.2742 (3) | 0.18243 (9) | −0.07135 (11) | 0.0541 (6) | |
C3 | 1.3252 (3) | 0.35979 (9) | −0.08998 (10) | 0.0553 (6) | |
C4 | 1.1802 (4) | 0.40612 (10) | −0.06064 (11) | 0.0599 (7) | |
C5 | 0.9873 (4) | 0.38760 (9) | −0.02008 (10) | 0.0598 (7) | |
C6 | 0.9357 (3) | 0.32199 (9) | −0.00793 (10) | 0.0529 (6) | |
C7 | 1.0829 (3) | 0.27313 (8) | −0.03608 (9) | 0.0436 (5) | |
C8 | 1.2754 (3) | 0.29322 (9) | −0.07754 (10) | 0.0456 (6) | |
C9 | 0.9184 (3) | 0.16023 (9) | 0.00909 (12) | 0.0554 (6) | |
C10 | 1.0162 (3) | 0.09284 (9) | 0.03068 (12) | 0.0614 (7) | |
C11 | 0.8718 (4) | 0.04992 (9) | 0.14913 (13) | 0.0550 (7) | |
C12 | 0.7144 (3) | 0.01537 (8) | 0.19354 (10) | 0.0479 (6) | |
C13 | 0.5134 (3) | −0.02203 (8) | 0.15551 (10) | 0.0488 (6) | |
C14 | 0.3631 (3) | −0.05484 (9) | 0.20536 (10) | 0.0514 (6) | |
C15 | 0.4034 (3) | −0.04853 (8) | 0.28556 (10) | 0.0482 (6) | |
C16 | 0.6007 (4) | −0.01132 (9) | 0.32228 (11) | 0.0553 (6) | |
C17 | 0.7519 (4) | 0.01853 (9) | 0.27684 (11) | 0.0557 (7) | |
C18 | 0.0976 (3) | −0.12825 (9) | 0.30843 (11) | 0.0555 (6) | |
C19 | 0.2329 (3) | −0.19171 (9) | 0.29849 (10) | 0.0468 (6) | |
C20 | 0.4546 (3) | −0.20537 (10) | 0.34351 (10) | 0.0551 (7) | |
C21 | 0.5697 (3) | −0.26495 (10) | 0.33539 (12) | 0.0633 (7) | |
C22 | 0.4657 (4) | −0.31237 (10) | 0.28371 (12) | 0.0650 (7) | |
C23 | 0.2467 (4) | −0.29912 (10) | 0.23859 (12) | 0.0639 (8) | |
C24 | 0.1331 (3) | −0.23922 (10) | 0.24611 (11) | 0.0562 (7) | |
H2N | 1.506 (4) | 0.2359 (10) | −0.1260 (11) | 0.069 (6)* | |
H2 | 1.31882 | 0.13859 | −0.07844 | 0.0650* | |
H1N | 0.692 (5) | 0.0289 (12) | 0.0442 (16) | 0.124 (9)* | |
H3 | 1.45310 | 0.37232 | −0.11740 | 0.0660* | |
H4 | 1.21088 | 0.45089 | −0.06789 | 0.0720* | |
H5 | 0.89146 | 0.42023 | −0.00084 | 0.0720* | |
H6 | 0.80493 | 0.31023 | 0.01861 | 0.0630* | |
H9A | 0.88553 | 0.18281 | 0.05692 | 0.0670* | |
H9B | 0.76469 | 0.15557 | −0.02483 | 0.0670* | |
H10A | 1.04499 | 0.06948 | −0.01707 | 0.0740* | |
H10B | 1.17118 | 0.09713 | 0.06398 | 0.0740* | |
H11 | 1.010 (3) | 0.0728 (8) | 0.1783 (9) | 0.050 (5)* | |
H14 | 0.23468 | −0.08114 | 0.18269 | 0.0620* | |
H16 | 0.62682 | −0.00730 | 0.37710 | 0.0660* | |
H17 | 0.88535 | 0.04199 | 0.30136 | 0.0670* | |
H18A | 0.00844 | −0.11556 | 0.25795 | 0.0670* | |
H18B | −0.01974 | −0.13537 | 0.34543 | 0.0670* | |
H20 | 0.52553 | −0.17406 | 0.37934 | 0.0660* | |
H21 | 0.71946 | −0.27329 | 0.36514 | 0.0760* | |
H22 | 0.54258 | −0.35297 | 0.27933 | 0.0780* | |
H23 | 0.17556 | −0.33064 | 0.20306 | 0.0770* | |
H24 | −0.01436 | −0.23062 | 0.21512 | 0.0670* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0792 (9) | 0.0719 (9) | 0.0439 (8) | −0.0150 (7) | 0.0081 (7) | 0.0055 (6) |
O2 | 0.0718 (8) | 0.0555 (8) | 0.0511 (7) | −0.0016 (7) | 0.0216 (6) | −0.0004 (6) |
N1 | 0.0630 (10) | 0.0418 (9) | 0.0651 (11) | −0.0024 (8) | 0.0200 (8) | 0.0074 (8) |
N2 | 0.0456 (9) | 0.0539 (10) | 0.0714 (10) | 0.0000 (8) | 0.0165 (8) | 0.0095 (8) |
C1 | 0.0403 (9) | 0.0470 (11) | 0.0526 (10) | −0.0021 (8) | −0.0007 (8) | 0.0092 (8) |
C2 | 0.0458 (10) | 0.0463 (11) | 0.0696 (12) | 0.0011 (9) | 0.0047 (9) | 0.0089 (9) |
C3 | 0.0506 (10) | 0.0559 (12) | 0.0593 (11) | −0.0095 (9) | 0.0069 (9) | 0.0097 (9) |
C4 | 0.0704 (12) | 0.0451 (11) | 0.0626 (12) | −0.0082 (10) | 0.0016 (10) | 0.0040 (9) |
C5 | 0.0717 (13) | 0.0520 (12) | 0.0561 (11) | 0.0035 (10) | 0.0093 (10) | −0.0014 (9) |
C6 | 0.0526 (10) | 0.0593 (12) | 0.0466 (10) | −0.0031 (9) | 0.0058 (8) | 0.0031 (9) |
C7 | 0.0415 (9) | 0.0470 (10) | 0.0407 (9) | −0.0025 (8) | −0.0010 (7) | 0.0053 (8) |
C8 | 0.0394 (9) | 0.0485 (11) | 0.0479 (10) | −0.0015 (8) | 0.0017 (8) | 0.0055 (8) |
C9 | 0.0445 (10) | 0.0519 (11) | 0.0695 (12) | −0.0050 (8) | 0.0058 (9) | 0.0122 (9) |
C10 | 0.0643 (12) | 0.0468 (11) | 0.0775 (13) | 0.0016 (10) | 0.0257 (10) | 0.0093 (10) |
C11 | 0.0576 (12) | 0.0395 (11) | 0.0685 (13) | 0.0035 (9) | 0.0105 (10) | 0.0014 (9) |
C12 | 0.0552 (10) | 0.0349 (9) | 0.0546 (11) | 0.0021 (8) | 0.0107 (9) | 0.0049 (8) |
C13 | 0.0584 (11) | 0.0403 (10) | 0.0485 (11) | 0.0053 (8) | 0.0101 (9) | 0.0025 (8) |
C14 | 0.0555 (10) | 0.0516 (11) | 0.0469 (11) | −0.0051 (9) | 0.0054 (8) | 0.0002 (8) |
C15 | 0.0571 (11) | 0.0409 (10) | 0.0486 (10) | 0.0050 (9) | 0.0147 (9) | 0.0008 (8) |
C16 | 0.0718 (12) | 0.0478 (11) | 0.0463 (10) | 0.0030 (10) | 0.0075 (10) | −0.0037 (8) |
C17 | 0.0617 (11) | 0.0449 (11) | 0.0588 (12) | −0.0043 (9) | 0.0013 (10) | −0.0025 (9) |
C18 | 0.0518 (10) | 0.0597 (12) | 0.0575 (11) | −0.0010 (9) | 0.0162 (9) | 0.0061 (9) |
C19 | 0.0458 (9) | 0.0527 (11) | 0.0434 (10) | −0.0029 (8) | 0.0111 (8) | 0.0072 (8) |
C20 | 0.0528 (11) | 0.0596 (12) | 0.0524 (11) | −0.0043 (9) | 0.0047 (9) | 0.0010 (9) |
C21 | 0.0525 (11) | 0.0713 (14) | 0.0644 (12) | 0.0054 (11) | 0.0003 (10) | 0.0095 (11) |
C22 | 0.0689 (13) | 0.0560 (12) | 0.0708 (13) | 0.0090 (11) | 0.0114 (11) | 0.0046 (11) |
C23 | 0.0703 (13) | 0.0573 (13) | 0.0636 (13) | −0.0063 (11) | 0.0060 (11) | −0.0024 (10) |
C24 | 0.0507 (10) | 0.0630 (13) | 0.0537 (11) | −0.0023 (10) | 0.0023 (9) | 0.0067 (9) |
O1—C13 | 1.281 (2) | C19—C24 | 1.376 (3) |
O2—C15 | 1.366 (2) | C19—C20 | 1.389 (2) |
O2—C18 | 1.437 (2) | C20—C21 | 1.375 (3) |
N1—C10 | 1.464 (2) | C21—C22 | 1.376 (3) |
N1—C11 | 1.297 (3) | C22—C23 | 1.376 (3) |
N2—C2 | 1.376 (2) | C23—C24 | 1.375 (3) |
N2—C8 | 1.368 (2) | C2—H2 | 0.9300 |
C1—C2 | 1.366 (2) | C3—H3 | 0.9300 |
C1—C7 | 1.430 (2) | C4—H4 | 0.9300 |
C1—C9 | 1.495 (2) | C5—H5 | 0.9300 |
N1—H1N | 1.07 (3) | C6—H6 | 0.9300 |
N2—H2N | 0.85 (2) | C9—H9A | 0.9700 |
C3—C8 | 1.392 (3) | C9—H9B | 0.9700 |
C3—C4 | 1.366 (3) | C10—H10A | 0.9700 |
C4—C5 | 1.392 (3) | C10—H10B | 0.9700 |
C5—C6 | 1.375 (3) | C11—H11 | 0.974 (16) |
C6—C7 | 1.400 (2) | C14—H14 | 0.9300 |
C7—C8 | 1.408 (2) | C16—H16 | 0.9300 |
C9—C10 | 1.492 (3) | C17—H17 | 0.9300 |
C11—C12 | 1.407 (3) | C18—H18A | 0.9700 |
C12—C17 | 1.409 (3) | C18—H18B | 0.9700 |
C12—C13 | 1.429 (2) | C20—H20 | 0.9300 |
C13—C14 | 1.423 (2) | C21—H21 | 0.9300 |
C14—C15 | 1.362 (2) | C22—H22 | 0.9300 |
C15—C16 | 1.404 (3) | C23—H23 | 0.9300 |
C16—C17 | 1.350 (3) | C24—H24 | 0.9300 |
C18—C19 | 1.503 (3) | ||
C15—O2—C18 | 117.81 (13) | C19—C24—C23 | 121.45 (17) |
C10—N1—C11 | 122.40 (17) | N2—C2—H2 | 125.00 |
C2—N2—C8 | 109.25 (15) | C1—C2—H2 | 125.00 |
C2—C1—C7 | 106.00 (15) | C4—C3—H3 | 121.00 |
C2—C1—C9 | 128.14 (16) | C8—C3—H3 | 121.00 |
C7—C1—C9 | 125.83 (15) | C3—C4—H4 | 119.00 |
C10—N1—H1N | 124.2 (15) | C5—C4—H4 | 119.00 |
C11—N1—H1N | 113.3 (15) | C4—C5—H5 | 119.00 |
N2—C2—C1 | 109.98 (16) | C6—C5—H5 | 119.00 |
C2—N2—H2N | 125.9 (14) | C5—C6—H6 | 120.00 |
C8—N2—H2N | 124.8 (14) | C7—C6—H6 | 120.00 |
C4—C3—C8 | 117.90 (16) | C1—C9—H9A | 109.00 |
C3—C4—C5 | 121.26 (18) | C1—C9—H9B | 109.00 |
C4—C5—C6 | 121.28 (18) | C10—C9—H9A | 109.00 |
C5—C6—C7 | 119.05 (16) | C10—C9—H9B | 109.00 |
C6—C7—C8 | 118.49 (15) | H9A—C9—H9B | 108.00 |
C1—C7—C8 | 107.82 (15) | N1—C10—H10A | 109.00 |
C1—C7—C6 | 133.69 (16) | N1—C10—H10B | 109.00 |
N2—C8—C7 | 106.94 (15) | C9—C10—H10A | 109.00 |
C3—C8—C7 | 122.01 (16) | C9—C10—H10B | 109.00 |
N2—C8—C3 | 131.04 (16) | H10A—C10—H10B | 108.00 |
C1—C9—C10 | 114.06 (14) | N1—C11—H11 | 117.0 (9) |
N1—C10—C9 | 112.07 (14) | C12—C11—H11 | 117.3 (9) |
N1—C11—C12 | 125.67 (19) | C13—C14—H14 | 119.00 |
C11—C12—C13 | 121.06 (16) | C15—C14—H14 | 119.00 |
C11—C12—C17 | 119.73 (17) | C15—C16—H16 | 120.00 |
C13—C12—C17 | 119.20 (16) | C17—C16—H16 | 120.00 |
O1—C13—C14 | 121.46 (15) | C12—C17—H17 | 119.00 |
C12—C13—C14 | 117.00 (15) | C16—C17—H17 | 119.00 |
O1—C13—C12 | 121.55 (15) | O2—C18—H18A | 109.00 |
C13—C14—C15 | 121.36 (16) | O2—C18—H18B | 109.00 |
C14—C15—C16 | 121.10 (16) | C19—C18—H18A | 109.00 |
O2—C15—C14 | 124.77 (15) | C19—C18—H18B | 109.00 |
O2—C15—C16 | 114.12 (15) | H18A—C18—H18B | 108.00 |
C15—C16—C17 | 119.03 (17) | C19—C20—H20 | 120.00 |
C12—C17—C16 | 122.24 (18) | C21—C20—H20 | 120.00 |
O2—C18—C19 | 111.79 (13) | C20—C21—H21 | 120.00 |
C18—C19—C20 | 121.59 (16) | C22—C21—H21 | 120.00 |
C18—C19—C24 | 120.10 (15) | C21—C22—H22 | 120.00 |
C20—C19—C24 | 118.26 (17) | C23—C22—H22 | 120.00 |
C19—C20—C21 | 120.34 (17) | C22—C23—H23 | 120.00 |
C20—C21—C22 | 120.71 (17) | C24—C23—H23 | 120.00 |
C21—C22—C23 | 119.32 (19) | C19—C24—H24 | 119.00 |
C22—C23—C24 | 119.91 (19) | C23—C24—H24 | 119.00 |
C18—O2—C15—C14 | 18.0 (2) | C1—C9—C10—N1 | 178.76 (15) |
C18—O2—C15—C16 | −163.17 (15) | N1—C11—C12—C13 | 2.9 (3) |
C15—O2—C18—C19 | 72.73 (18) | N1—C11—C12—C17 | −175.88 (18) |
C11—N1—C10—C9 | −96.7 (2) | C11—C12—C13—O1 | 0.7 (3) |
C10—N1—C11—C12 | 177.96 (17) | C11—C12—C13—C14 | −179.48 (16) |
C8—N2—C2—C1 | 0.1 (2) | C17—C12—C13—O1 | 179.48 (16) |
C2—N2—C8—C3 | 178.73 (18) | C17—C12—C13—C14 | −0.7 (2) |
C2—N2—C8—C7 | −0.4 (2) | C11—C12—C17—C16 | 177.17 (18) |
C7—C1—C2—N2 | 0.3 (2) | C13—C12—C17—C16 | −1.6 (3) |
C9—C1—C2—N2 | −177.68 (17) | O1—C13—C14—C15 | −177.50 (16) |
C2—C1—C7—C6 | 179.80 (18) | C12—C13—C14—C15 | 2.7 (2) |
C2—C1—C7—C8 | −0.48 (19) | C13—C14—C15—O2 | 176.31 (15) |
C9—C1—C7—C6 | −2.2 (3) | C13—C14—C15—C16 | −2.4 (3) |
C9—C1—C7—C8 | 177.52 (16) | O2—C15—C16—C17 | −178.82 (17) |
C2—C1—C9—C10 | 20.0 (3) | C14—C15—C16—C17 | 0.0 (3) |
C7—C1—C9—C10 | −157.53 (17) | C15—C16—C17—C12 | 2.0 (3) |
C8—C3—C4—C5 | −0.5 (3) | O2—C18—C19—C20 | 27.2 (2) |
C4—C3—C8—N2 | −179.09 (19) | O2—C18—C19—C24 | −155.53 (16) |
C4—C3—C8—C7 | −0.1 (3) | C18—C19—C20—C21 | 177.42 (17) |
C3—C4—C5—C6 | 0.1 (3) | C24—C19—C20—C21 | 0.1 (3) |
C4—C5—C6—C7 | 0.9 (3) | C18—C19—C24—C23 | −176.71 (17) |
C5—C6—C7—C1 | 178.23 (18) | C20—C19—C24—C23 | 0.7 (3) |
C5—C6—C7—C8 | −1.5 (2) | C19—C20—C21—C22 | −1.1 (3) |
C1—C7—C8—N2 | 0.52 (19) | C20—C21—C22—C23 | 1.4 (3) |
C1—C7—C8—C3 | −178.67 (16) | C21—C22—C23—C24 | −0.7 (3) |
C6—C7—C8—N2 | −179.71 (15) | C22—C23—C24—C19 | −0.4 (3) |
C6—C7—C8—C3 | 1.1 (2) |
Cg1, Cg2 and Cg4 are the centroids of rings N2/C1/C2/C7/C8, C3–C8 and C19–C24, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1 | 1.07 (3) | 1.81 (3) | 2.657 (2) | 133 (2) |
N1—H1N···O1i | 1.07 (3) | 2.19 (3) | 3.004 (2) | 131 (2) |
C2—H2···O1ii | 0.93 | 2.55 | 3.467 (2) | 167 |
C23—H23···Cg2i | 0.93 | 2.95 | 3.716 (2) | 141 |
C24—H24···Cg1i | 0.93 | 2.70 | 3.465 (3) | 140 |
N2—H2N···Cg4ii | 0.85 (2) | 3.03 (2) | 3.75 (3) | 145 (2) |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x+2, −y, −z. |
Absorbances | ||||||||
12.5 µg | 25 µg | 50 µg | 100 µg | 200 µg | 400 µg | 800 µg | A0.50 (µg/ml) | |
Compound (I) | 0.18±0.00 | 0.23±0.01 | 0.31±0.01 | 0.47±0.01 | 0.67±0.07 | 1.14±0.14 | 2.38±0.25 | >100 |
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 Constantine 1, Algeria, for funding this research project.
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