organic compounds
N′-[(E)-4-Chlorobenzylidene]-2-(2,3-dimethylanilino)benzohydrazide
aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, cChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, dChemistry Department, Faculty of Science, Mini University, 61519 El-Minia, Egypt, and eDepartment of Chemistry, College of Education, Kirkuk University, Kirkuk, Iraq
*Correspondence e-mail: shaabankamel@yahoo.com
In the title compound, C22H20ClN3O, the dihedral angle between the planes of the chlorophenyl and dimethylphenyl rings is 66.50 (9)°. These rings make dihedral angles 47.79 (8) and 69.24 (9)°, respectively, with the central benzene ring. In the crystal, molecules are linked into a three-dimensional supramolecular network by N—H⋯O, C—H⋯O hydrogen bonds and weak C—H⋯π interactions.
Keywords: crystal structure; mefenamic acid; non-steroidal anti-inflammatory drug (NSAID); hydrazones.
CCDC reference: 1569084
Structure description
Mefenamic acid (MA) is a non-steroidal anti-inflammatory drug (NSAID), which has analgesic, anti-inflammatory and antipyretic actions (Idowu et al., 2002). In addition, it can be indicated for the treatment of primary dysmenorrhea (Zhang & Wan, 1998) and periodontitis (Corry & Moran, 1998). The main side effects of MA include peptic ulceration and gastric bleeding, which can be attributed to the combination of local irritation produced by the direct contact of the free carboxylic group (Arun & Ashok, 2009; Tegeli & More, 2014). It has also been reported that compounds containing the hydrazide-hydrazone or imide moiety possess good analgesic and anti-inflammatory activity (Mohamed et al., 2012). A number of hydrazidehydrazones have been demonstrated to possess interesting antidepressant, antibacterial, antifungal, anticonvulsant, anti-inflammatory, antimalarial and antituberculosis activities (Mohamed et al., 2015a,b). Based on these findings and further to our previous interest in the synthesis of hydrazone NSAIDs, we report herein the synthesis and determination of the title compound.
The title molecule (Fig. 1) is twisted with a dihedral angle of 66.50 (9)° between the chlorophenyl and dimethylphenyl rings. The chlorophenyl and dimethylphenyl rings make dihedral angles 47.79 (8) of and 69.24 (9)°, respectively, with the central benzene ring. The methyl groups of the 2,3-dimethylphenyl unit are co-planar with its bound benzene ring [C21—C19—C20—C22 = −1.9 (3)°]. The middle bridging fragment (C1/N1/N2/O1/C8) is not planar with the torsion angle N1—N2—C8—O1 = 16.3 (2)°. All bond lengths and angles are within normal ranges and are comparable with those in related structures (Zhen & Han, 2005; Chantrapromma et al., 2014; Fun et al., 2011; Horkaew et al., 2012).
In the crystal (Fig. 2), the molecules are linked by N—H⋯O, and C—H⋯O hydrogen bonds (Table 1) into a three dimensional network. A weak C—H⋯π interaction (Table 1) is also observed.
Synthesis and crystallization
The title compound was synthesized according to our previously reported procedure (Mohamed et al., 2015b). The crystals were collected and recrystallized from ethanol to afford pure crystals suitable for X-ray analysis with m.p. = 473 − 477 K.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2
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Structural data
CCDC reference: 1569084
https://doi.org/10.1107/S2414314617011877/xu4030sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617011877/xu4030Isup2.hkl
Data collection: CrysAlis PRO (Agilent, 2014); cell
CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and WinGX (Farrugia, 2012).C22H20ClN3O | F(000) = 792 |
Mr = 377.86 | Dx = 1.289 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54184 Å |
a = 15.6759 (5) Å | Cell parameters from 2873 reflections |
b = 15.7743 (5) Å | θ = 4.0–71.1° |
c = 8.0115 (3) Å | µ = 1.86 mm−1 |
β = 100.530 (3)° | T = 171 K |
V = 1947.69 (12) Å3 | Prism, colourless |
Z = 4 | 0.4 × 0.4 × 0.3 mm |
Agilent Xcalibur Eos Gemini diffractometer | 3703 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Cu) X-ray Source | 3188 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
Detector resolution: 16.0416 pixels mm-1 | θmax = 71.3°, θmin = 4.0° |
ω scans | h = −11→19 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014) | k = −11→19 |
Tmin = 0.833, Tmax = 1.000 | l = −9→9 |
7282 measured reflections |
Refinement on F2 | 2 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.046 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.132 | w = 1/[σ2(Fo2) + (0.0805P)2 + 0.2369P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max = 0.001 |
3703 reflections | Δρmax = 0.25 e Å−3 |
252 parameters | Δρmin = −0.32 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
Refinement. The C-bound H atoms were placed in calculated positions and allowed to ride on their carrier atoms: aromatic C—H = 0.95 Å, with Uiso(H) = 1.2Ueq(C), C—Hmethyl = 0.98 Å with Uiso(H) = 1.5Ueq(C). The H atom of the NH group was found in a difference Fourier map and refined with N—H = 0.87 (2) Å, with Uiso(H) = 1.2Ueq(N). |
x | y | z | Uiso*/Ueq | ||
C1 | 0.70836 (10) | 0.18574 (10) | 0.3822 (2) | 0.0263 (3) | |
H1 | 0.6838 | 0.1555 | 0.2825 | 0.032* | |
C2 | 0.79706 (10) | 0.16644 (10) | 0.4687 (2) | 0.0248 (3) | |
C3 | 0.83570 (11) | 0.21061 (11) | 0.6143 (2) | 0.0315 (4) | |
H3A | 0.8025 | 0.2506 | 0.6640 | 0.038* | |
C4 | 0.92144 (11) | 0.19700 (11) | 0.6868 (2) | 0.0337 (4) | |
H4 | 0.9470 | 0.2266 | 0.7867 | 0.040* | |
C5 | 0.96965 (11) | 0.13950 (10) | 0.6119 (2) | 0.0302 (4) | |
C6 | 0.93316 (11) | 0.09513 (10) | 0.4677 (2) | 0.0307 (4) | |
H6 | 0.9669 | 0.0560 | 0.4173 | 0.037* | |
C7 | 0.84679 (11) | 0.10853 (10) | 0.3977 (2) | 0.0279 (3) | |
H7 | 0.8211 | 0.0776 | 0.2995 | 0.033* | |
C8 | 0.53377 (10) | 0.32116 (10) | 0.3908 (2) | 0.0253 (3) | |
C9 | 0.46765 (10) | 0.36110 (10) | 0.2587 (2) | 0.0267 (3) | |
C10 | 0.48285 (13) | 0.36930 (12) | 0.0929 (2) | 0.0371 (4) | |
H10 | 0.5355 | 0.3481 | 0.0662 | 0.045* | |
C11 | 0.42359 (16) | 0.40722 (14) | −0.0327 (2) | 0.0483 (5) | |
H11 | 0.4354 | 0.4131 | −0.1443 | 0.058* | |
C12 | 0.34591 (14) | 0.43681 (13) | 0.0065 (2) | 0.0456 (5) | |
H12 | 0.3038 | 0.4617 | −0.0801 | 0.055* | |
C13 | 0.32920 (12) | 0.43061 (12) | 0.1687 (2) | 0.0368 (4) | |
H13 | 0.2755 | 0.4509 | 0.1921 | 0.044* | |
C14 | 0.39028 (11) | 0.39477 (11) | 0.3009 (2) | 0.0293 (4) | |
C15 | 0.30223 (11) | 0.42961 (12) | 0.5171 (2) | 0.0311 (4) | |
C16 | 0.29755 (13) | 0.51764 (13) | 0.5204 (3) | 0.0414 (4) | |
H16 | 0.3419 | 0.5508 | 0.4862 | 0.050* | |
C17 | 0.22818 (15) | 0.55678 (13) | 0.5735 (3) | 0.0480 (5) | |
H17 | 0.2247 | 0.6169 | 0.5764 | 0.058* | |
C18 | 0.16424 (14) | 0.50783 (14) | 0.6223 (3) | 0.0452 (5) | |
H18 | 0.1161 | 0.5348 | 0.6568 | 0.054* | |
C19 | 0.16843 (12) | 0.42067 (13) | 0.6221 (2) | 0.0375 (4) | |
C20 | 0.23916 (11) | 0.37978 (11) | 0.5699 (2) | 0.0315 (4) | |
C21 | 0.09662 (17) | 0.36903 (19) | 0.6768 (4) | 0.0660 (7) | |
H21A | 0.0783 | 0.3240 | 0.5938 | 0.099* | |
H21B | 0.0472 | 0.4060 | 0.6838 | 0.099* | |
H21C | 0.1180 | 0.3437 | 0.7884 | 0.099* | |
C22 | 0.24639 (16) | 0.28469 (13) | 0.5726 (3) | 0.0508 (5) | |
H22A | 0.2962 | 0.2675 | 0.5224 | 0.076* | |
H22B | 0.1933 | 0.2601 | 0.5070 | 0.076* | |
H22C | 0.2544 | 0.2645 | 0.6901 | 0.076* | |
Cl1 | 1.07800 (3) | 0.12222 (3) | 0.70239 (7) | 0.04846 (18) | |
N1 | 0.66402 (8) | 0.24281 (9) | 0.43998 (17) | 0.0265 (3) | |
N2 | 0.58792 (8) | 0.26525 (9) | 0.33423 (18) | 0.0277 (3) | |
H2N | 0.5781 (13) | 0.2445 (13) | 0.236 (2) | 0.033* | |
N3 | 0.37413 (10) | 0.39047 (12) | 0.4626 (2) | 0.0417 (4) | |
H3N | 0.4163 (13) | 0.3735 (15) | 0.537 (3) | 0.050* | |
O1 | 0.54090 (7) | 0.33759 (8) | 0.54416 (14) | 0.0299 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0240 (7) | 0.0287 (8) | 0.0257 (7) | −0.0011 (6) | 0.0032 (6) | 0.0006 (6) |
C2 | 0.0233 (7) | 0.0239 (7) | 0.0272 (8) | −0.0004 (6) | 0.0047 (6) | 0.0034 (6) |
C3 | 0.0296 (8) | 0.0324 (8) | 0.0321 (8) | 0.0043 (7) | 0.0042 (7) | −0.0058 (7) |
C4 | 0.0316 (8) | 0.0329 (9) | 0.0339 (8) | 0.0008 (7) | −0.0014 (7) | −0.0046 (7) |
C5 | 0.0226 (7) | 0.0262 (8) | 0.0400 (9) | 0.0006 (6) | 0.0006 (6) | 0.0064 (7) |
C6 | 0.0304 (8) | 0.0238 (7) | 0.0385 (9) | 0.0059 (6) | 0.0079 (7) | 0.0024 (7) |
C7 | 0.0303 (8) | 0.0243 (7) | 0.0286 (8) | 0.0004 (6) | 0.0041 (6) | −0.0002 (6) |
C8 | 0.0198 (7) | 0.0287 (7) | 0.0273 (8) | −0.0010 (6) | 0.0038 (6) | 0.0015 (6) |
C9 | 0.0256 (8) | 0.0275 (7) | 0.0257 (7) | 0.0010 (6) | 0.0010 (6) | 0.0014 (6) |
C10 | 0.0424 (10) | 0.0393 (9) | 0.0299 (9) | 0.0101 (8) | 0.0075 (7) | 0.0023 (7) |
C11 | 0.0655 (14) | 0.0534 (12) | 0.0248 (9) | 0.0192 (11) | 0.0050 (9) | 0.0050 (8) |
C12 | 0.0550 (12) | 0.0445 (11) | 0.0309 (9) | 0.0191 (9) | −0.0092 (8) | 0.0018 (8) |
C13 | 0.0336 (9) | 0.0368 (9) | 0.0366 (9) | 0.0093 (7) | −0.0032 (7) | −0.0008 (7) |
C14 | 0.0256 (8) | 0.0311 (8) | 0.0301 (8) | 0.0014 (6) | 0.0019 (6) | 0.0029 (7) |
C15 | 0.0259 (8) | 0.0379 (9) | 0.0285 (8) | 0.0065 (7) | 0.0026 (6) | 0.0045 (7) |
C16 | 0.0432 (10) | 0.0367 (10) | 0.0423 (10) | −0.0058 (8) | 0.0026 (8) | 0.0058 (8) |
C17 | 0.0661 (14) | 0.0301 (9) | 0.0455 (11) | 0.0111 (9) | 0.0039 (10) | −0.0010 (8) |
C18 | 0.0495 (11) | 0.0475 (11) | 0.0401 (10) | 0.0195 (9) | 0.0125 (8) | −0.0032 (8) |
C19 | 0.0338 (9) | 0.0460 (10) | 0.0345 (9) | 0.0040 (8) | 0.0111 (7) | −0.0005 (8) |
C20 | 0.0330 (9) | 0.0322 (9) | 0.0292 (8) | 0.0040 (7) | 0.0057 (7) | −0.0002 (6) |
C21 | 0.0525 (14) | 0.0758 (17) | 0.0790 (18) | 0.0007 (12) | 0.0363 (13) | 0.0073 (14) |
C22 | 0.0660 (14) | 0.0329 (10) | 0.0581 (13) | 0.0035 (9) | 0.0237 (11) | 0.0012 (9) |
Cl1 | 0.0259 (2) | 0.0426 (3) | 0.0702 (4) | 0.00625 (17) | −0.0086 (2) | −0.0052 (2) |
N1 | 0.0202 (6) | 0.0328 (7) | 0.0256 (7) | 0.0014 (5) | 0.0017 (5) | 0.0011 (5) |
N2 | 0.0222 (6) | 0.0360 (7) | 0.0232 (7) | 0.0039 (5) | −0.0001 (5) | −0.0011 (6) |
N3 | 0.0281 (8) | 0.0637 (11) | 0.0339 (8) | 0.0181 (7) | 0.0075 (6) | 0.0143 (7) |
O1 | 0.0263 (6) | 0.0389 (6) | 0.0235 (5) | 0.0050 (5) | 0.0021 (4) | 0.0003 (5) |
C1—N1 | 1.275 (2) | C13—C14 | 1.410 (2) |
C1—C2 | 1.468 (2) | C13—H13 | 0.9500 |
C1—H1 | 0.9500 | C14—N3 | 1.367 (2) |
C2—C7 | 1.388 (2) | C15—C20 | 1.388 (2) |
C2—C3 | 1.398 (2) | C15—C16 | 1.391 (3) |
C3—C4 | 1.380 (2) | C15—N3 | 1.422 (2) |
C3—H3A | 0.9500 | C16—C17 | 1.384 (3) |
C4—C5 | 1.385 (3) | C16—H16 | 0.9500 |
C4—H4 | 0.9500 | C17—C18 | 1.377 (3) |
C5—C6 | 1.382 (3) | C17—H17 | 0.9500 |
C5—Cl1 | 1.7419 (16) | C18—C19 | 1.377 (3) |
C6—C7 | 1.384 (2) | C18—H18 | 0.9500 |
C6—H6 | 0.9500 | C19—C20 | 1.411 (2) |
C7—H7 | 0.9500 | C19—C21 | 1.518 (3) |
C8—O1 | 1.241 (2) | C20—C22 | 1.504 (3) |
C8—N2 | 1.358 (2) | C21—H21A | 0.9800 |
C8—C9 | 1.480 (2) | C21—H21B | 0.9800 |
C9—C10 | 1.398 (2) | C21—H21C | 0.9800 |
C9—C14 | 1.420 (2) | C22—H22A | 0.9800 |
C10—C11 | 1.375 (3) | C22—H22B | 0.9800 |
C10—H10 | 0.9500 | C22—H22C | 0.9800 |
C11—C12 | 1.393 (3) | N1—N2 | 1.3772 (18) |
C11—H11 | 0.9500 | N2—H2N | 0.843 (16) |
C12—C13 | 1.375 (3) | N3—H3N | 0.846 (16) |
C12—H12 | 0.9500 | ||
N1—C1—C2 | 120.50 (15) | N3—C14—C9 | 121.42 (15) |
N1—C1—H1 | 119.7 | C13—C14—C9 | 117.62 (16) |
C2—C1—H1 | 119.7 | C20—C15—C16 | 121.10 (17) |
C7—C2—C3 | 118.65 (15) | C20—C15—N3 | 119.75 (17) |
C7—C2—C1 | 119.84 (15) | C16—C15—N3 | 119.13 (17) |
C3—C2—C1 | 121.27 (15) | C17—C16—C15 | 119.90 (18) |
C4—C3—C2 | 120.92 (16) | C17—C16—H16 | 120.0 |
C4—C3—H3A | 119.5 | C15—C16—H16 | 120.1 |
C2—C3—H3A | 119.5 | C18—C17—C16 | 119.39 (18) |
C3—C4—C5 | 119.07 (16) | C18—C17—H17 | 120.3 |
C3—C4—H4 | 120.5 | C16—C17—H17 | 120.3 |
C5—C4—H4 | 120.5 | C19—C18—C17 | 121.49 (18) |
C6—C5—C4 | 121.22 (15) | C19—C18—H18 | 119.3 |
C6—C5—Cl1 | 119.45 (13) | C17—C18—H18 | 119.3 |
C4—C5—Cl1 | 119.32 (14) | C18—C19—C20 | 119.83 (18) |
C5—C6—C7 | 119.09 (16) | C18—C19—C21 | 119.84 (19) |
C5—C6—H6 | 120.5 | C20—C19—C21 | 120.33 (19) |
C7—C6—H6 | 120.5 | C15—C20—C19 | 118.26 (16) |
C6—C7—C2 | 121.04 (15) | C15—C20—C22 | 120.87 (17) |
C6—C7—H7 | 119.5 | C19—C20—C22 | 120.86 (18) |
C2—C7—H7 | 119.5 | C19—C21—H21A | 109.5 |
O1—C8—N2 | 121.16 (14) | C19—C21—H21B | 109.5 |
O1—C8—C9 | 122.94 (15) | H21A—C21—H21B | 109.5 |
N2—C8—C9 | 115.90 (14) | C19—C21—H21C | 109.5 |
C10—C9—C14 | 119.52 (15) | H21A—C21—H21C | 109.5 |
C10—C9—C8 | 120.00 (15) | H21B—C21—H21C | 109.5 |
C14—C9—C8 | 120.41 (15) | C20—C22—H22A | 109.5 |
C11—C10—C9 | 121.73 (18) | C20—C22—H22B | 109.5 |
C11—C10—H10 | 119.1 | H22A—C22—H22B | 109.5 |
C9—C10—H10 | 119.1 | C20—C22—H22C | 109.5 |
C10—C11—C12 | 118.82 (18) | H22A—C22—H22C | 109.5 |
C10—C11—H11 | 120.6 | H22B—C22—H22C | 109.5 |
C12—C11—H11 | 120.6 | C1—N1—N2 | 115.25 (14) |
C13—C12—C11 | 120.98 (17) | C8—N2—N1 | 119.05 (14) |
C13—C12—H12 | 119.5 | C8—N2—H2N | 123.1 (14) |
C11—C12—H12 | 119.5 | N1—N2—H2N | 117.8 (14) |
C12—C13—C14 | 121.20 (17) | C14—N3—C15 | 124.34 (15) |
C12—C13—H13 | 119.4 | C14—N3—H3N | 115.0 (18) |
C14—C13—H13 | 119.4 | C15—N3—H3N | 118.9 (18) |
N3—C14—C13 | 120.93 (16) | ||
N1—C1—C2—C7 | −175.36 (15) | C10—C9—C14—C13 | 4.0 (3) |
N1—C1—C2—C3 | −1.0 (2) | C8—C9—C14—C13 | −178.89 (15) |
C7—C2—C3—C4 | −0.2 (3) | C20—C15—C16—C17 | −1.4 (3) |
C1—C2—C3—C4 | −174.63 (16) | N3—C15—C16—C17 | −179.80 (17) |
C2—C3—C4—C5 | 0.9 (3) | C15—C16—C17—C18 | −0.2 (3) |
C3—C4—C5—C6 | −0.7 (3) | C16—C17—C18—C19 | 1.1 (3) |
C3—C4—C5—Cl1 | 179.80 (14) | C17—C18—C19—C20 | −0.5 (3) |
C4—C5—C6—C7 | −0.2 (3) | C17—C18—C19—C21 | 179.9 (2) |
Cl1—C5—C6—C7 | 179.30 (13) | C16—C15—C20—C19 | 2.0 (3) |
C5—C6—C7—C2 | 0.9 (3) | N3—C15—C20—C19 | −179.61 (16) |
C3—C2—C7—C6 | −0.7 (2) | C16—C15—C20—C22 | −177.56 (19) |
C1—C2—C7—C6 | 173.79 (15) | N3—C15—C20—C22 | 0.8 (3) |
O1—C8—C9—C10 | 153.40 (17) | C18—C19—C20—C15 | −1.1 (3) |
N2—C8—C9—C10 | −25.9 (2) | C21—C19—C20—C15 | 178.51 (19) |
O1—C8—C9—C14 | −23.7 (2) | C18—C19—C20—C22 | 178.48 (19) |
N2—C8—C9—C14 | 157.00 (15) | C21—C19—C20—C22 | −1.9 (3) |
C14—C9—C10—C11 | −1.8 (3) | C2—C1—N1—N2 | 169.64 (14) |
C8—C9—C10—C11 | −178.97 (19) | O1—C8—N2—N1 | −16.3 (2) |
C9—C10—C11—C12 | −1.1 (3) | C9—C8—N2—N1 | 162.97 (14) |
C10—C11—C12—C13 | 1.8 (3) | C1—N1—N2—C8 | 175.36 (14) |
C11—C12—C13—C14 | 0.5 (3) | C13—C14—N3—C15 | −8.1 (3) |
C12—C13—C14—N3 | 178.55 (19) | C9—C14—N3—C15 | 173.89 (18) |
C12—C13—C14—C9 | −3.4 (3) | C20—C15—N3—C14 | 115.0 (2) |
C10—C9—C14—N3 | −177.95 (17) | C16—C15—N3—C14 | −66.6 (3) |
C8—C9—C14—N3 | −0.8 (3) |
Cg3 is the centroid of the C15–C20 benzene ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2N···O1i | 0.84 (2) | 2.01 (2) | 2.8195 (18) | 161 (2) |
N3—H3N···O1 | 0.85 (2) | 2.02 (2) | 2.708 (2) | 137 (2) |
C16—H16···O1ii | 0.95 | 2.59 | 3.518 (2) | 166 |
C12—H12···Cg3iii | 0.95 | 2.81 | 3.6466 (19) | 147 |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) −x+1, −y+1, −z+1; (iii) x, y, z−1. |
Acknowledgements
JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer data.
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