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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

N-[4-(Azetidin-1-ylsulfon­yl)phen­yl]-N-(2,4-di­fluoro­benz­yl)acetamide

aSichuan Provincial People's Hospital, Chengdu 610072, People's Republic of China, bLaboratory of Bioorganic & Medicinal Chemistry, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China, and cSchool of Chemistry and Chemical Engineering, Bijie University, Bijie, Guizhou 551700, People's Republic of China
*Correspondence e-mail: ljs1234@swu.edu.cn

(Received 30 August 2012; accepted 7 September 2012; online 15 September 2012)

In the title mol­ecule, C18H18F2N2O3S, the dihedral angle between the benzene rings is 79.40 (11)°. The 2,4-difluoro­benzyl and azetidine fragments adopt a trans arrangement relative to the central benzene ring. In the crystal, weak C—H⋯O hydrogen bonds connect mol­ecules into a two-dimensional network parallel to (001).

Related literature

For the pharmacological activity of sulfonamides, see: Song et al. (2007[Song, C.-Z., Zhou, C.-H. & Yuan, Y. (2007). Chin. J. New Drugs, 16, 1438-1444 (in Chinese).]); Wang, Wang et al. (2010[Wang, X.-L., Wang, X.-L., Geng, R.-X. & Zhou, C.-H. (2010). Chin. J. New Drugs, 19, 2050-2059.]); Wang, Wan & Zhou (2010[Wang, X.-L., Wan, K. & Zhou, C.-H. (2010). Eur. J. Med. Chem. 45, 4631-4639.]); Wang, Gan et al. (2010[Wang, X.-L., Gan, L.-L., Yan, C.-Y. & Zhou, C.-H. (2010). Sci. Sin. Chim. 41, 451-460.]).

[Scheme 1]

Experimental

Crystal data
  • C18H18F2N2O3S

  • Mr = 380.40

  • Monoclinic, P 21 /c

  • a = 8.7793 (15) Å

  • b = 8.4442 (15) Å

  • c = 23.810 (4) Å

  • β = 97.312 (6)°

  • V = 1750.8 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 293 K

  • 0.22 × 0.21 × 0.20 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.000, Tmax = 0.001

  • 14668 measured reflections

  • 3077 independent reflections

  • 2684 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.047

  • wR(F2) = 0.143

  • S = 1.04

  • 3077 reflections

  • 236 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H3⋯O3i 0.93 2.44 3.336 (3) 162
C11—H9⋯O1ii 0.93 2.51 3.406 (3) 162
C17—H18B⋯O1iii 0.97 2.56 3.509 (4) 166
Symmetry codes: (i) x, y+1, z; (ii) -x+1, -y+1, -z+1; (iii) -x, -y+1, -z+1.

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Sulfonamides were extensively employed as effective antimicrobial agents for the prevention and cure of bacterial infections in humanbiological systems as early as 70 years ago, and recently have aroused considerable interest in biology and medicine for their diversified pharmacological activities including antibacterial, antifungal, antiviral, antitumor, anti-inflammatory and as carbonic anhydrase inhibitors (Song, et al., 2007; Wang, Wang et al., 2010). Our interest is to develop novel sulfonamide derivatives as antimicrobial agents and some structrally related sulfonamides have been reported as bioactive agents (Wang, Wan & Zhou, 2010; Wang & Gan et al., 2010). Herein, we report the crystal structure of the title compound (I).

In the molecule of (I) (Fig. 1) the dihedral angle between the two benzene rings is 79.40 (11)°. The 2,4-difluorobenzyl and azetidine fragments adopt a trans arrangement relative to the central benzene ring. In the crystal, weak C—H···O hydrogen bonds connect molecules into a two-dimensional network (Fig. 2) parallel to (001).

Related literature top

For the pharmacological activity of sulfonamides, see: Song et al. (2007); Wang, Wang et al. (2010); Wang, Wan et al. (2010); Wang, Gan et al. (2010).

Experimental top

A suspension of N-(4-(azetidin-1-ylsulfonyl)phenyl)acetamide (0.8 g, 3.0 mmol) and potassium carbonate (0.5 g, 3.6 mmol) was stirred in acetonitrile (30 mL) at 343 K. After half an hour, 1-(bromomethyl)-2,4-difluorobenzene (0.6 g, 3.0 mmol) was added, and the progress of the reaction was monitored by TLC. Upon completion, the reaction was extracted with chloroform (3 × 20 mL). The filtrate was concentrated and then directly purified by chromatographic column (petroleum ether/ethyl acetate) to afford the title compound (I). A crystal suitable for X-ray analysis was grown from a solution of (I) in a mixture of acetone and ethyl acetate by slow evaporation at room temperature.

Refinement top

H atoms were placed at calculated position with C—H = 0.93 Å (aromatic), 0.97Å (methylene) 0.96 Å (methyl). The Uiso(H) value was set equal to 1.2Ueq(C) or 1.5Ueq(Cmethyl).

Structure description top

Sulfonamides were extensively employed as effective antimicrobial agents for the prevention and cure of bacterial infections in humanbiological systems as early as 70 years ago, and recently have aroused considerable interest in biology and medicine for their diversified pharmacological activities including antibacterial, antifungal, antiviral, antitumor, anti-inflammatory and as carbonic anhydrase inhibitors (Song, et al., 2007; Wang, Wang et al., 2010). Our interest is to develop novel sulfonamide derivatives as antimicrobial agents and some structrally related sulfonamides have been reported as bioactive agents (Wang, Wan & Zhou, 2010; Wang & Gan et al., 2010). Herein, we report the crystal structure of the title compound (I).

In the molecule of (I) (Fig. 1) the dihedral angle between the two benzene rings is 79.40 (11)°. The 2,4-difluorobenzyl and azetidine fragments adopt a trans arrangement relative to the central benzene ring. In the crystal, weak C—H···O hydrogen bonds connect molecules into a two-dimensional network (Fig. 2) parallel to (001).

For the pharmacological activity of sulfonamides, see: Song et al. (2007); Wang, Wang et al. (2010); Wang, Wan et al. (2010); Wang, Gan et al. (2010).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Part of the crystal structure with hydrogen bonds shown as dashed lines.
N-[4-(Azetidin-1-ylsulfonyl)phenyl]-N-(2,4-difluorobenzyl) acetamide top
Crystal data top
C18H18F2N2O3SF(000) = 792
Mr = 380.40Dx = 1.443 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2005 reflections
a = 8.7793 (15) Åθ = 1.3–25.0°
b = 8.4442 (15) ŵ = 0.23 mm1
c = 23.810 (4) ÅT = 293 K
β = 97.312 (6)°Plate, colourless
V = 1750.8 (5) Å30.22 × 0.21 × 0.20 mm
Z = 4
Data collection top
Bruker SMART CCD
diffractometer
3077 independent reflections
Radiation source: fine-focus sealed tube2684 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
φ and ω scansθmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1010
Tmin = 0.000, Tmax = 0.001k = 910
14668 measured reflectionsl = 2528
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.047H-atom parameters constrained
wR(F2) = 0.143 w = 1/[σ2(Fo2) + (0.0875P)2 + 0.736P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
3077 reflectionsΔρmax = 0.34 e Å3
236 parametersΔρmin = 0.38 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.017 (2)
Crystal data top
C18H18F2N2O3SV = 1750.8 (5) Å3
Mr = 380.40Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.7793 (15) ŵ = 0.23 mm1
b = 8.4442 (15) ÅT = 293 K
c = 23.810 (4) Å0.22 × 0.21 × 0.20 mm
β = 97.312 (6)°
Data collection top
Bruker SMART CCD
diffractometer
3077 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2684 reflections with I > 2σ(I)
Tmin = 0.000, Tmax = 0.001Rint = 0.036
14668 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.143H-atom parameters constrained
S = 1.04Δρmax = 0.34 e Å3
3077 reflectionsΔρmin = 0.38 e Å3
236 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.6694 (2)0.5645 (3)0.33594 (10)0.0447 (5)
C60.5341 (2)0.5834 (2)0.35904 (9)0.0365 (5)
C50.4212 (3)0.6715 (3)0.32755 (10)0.0490 (6)
H30.32910.68990.34190.059*
C40.4418 (3)0.7332 (3)0.27524 (11)0.0597 (7)
H40.36470.79210.25440.072*
C30.5781 (3)0.7056 (3)0.25474 (11)0.0585 (7)
C20.6955 (3)0.6231 (3)0.28413 (12)0.0580 (7)
H60.78830.60730.27000.070*
C130.1006 (2)0.1070 (3)0.36580 (9)0.0385 (5)
C120.2177 (3)0.0895 (3)0.41033 (10)0.0432 (5)
H80.24010.00990.42610.052*
C110.3003 (2)0.2199 (3)0.43111 (9)0.0403 (5)
H90.37930.20880.46080.048*
C100.2657 (2)0.3687 (2)0.40761 (8)0.0340 (5)
C140.0659 (2)0.2550 (3)0.34245 (9)0.0416 (5)
H110.01290.26610.31270.050*
C150.1482 (2)0.3860 (3)0.36341 (10)0.0408 (5)
H120.12490.48550.34790.049*
C160.2870 (3)0.0478 (3)0.36281 (14)0.0658 (8)
H13A0.36870.02610.33240.079*
H13B0.25260.15670.36160.079*
C80.3049 (2)0.6238 (2)0.45767 (9)0.0370 (5)
C90.1495 (3)0.6048 (3)0.47658 (11)0.0512 (6)
H15A0.10500.50650.46250.077*
H15B0.08460.69090.46210.077*
H15C0.15940.60500.51720.077*
C70.5160 (2)0.5089 (3)0.41508 (9)0.0401 (5)
H7A0.55620.40190.41550.048*
H7B0.57740.56790.44480.048*
C180.1690 (3)0.0912 (4)0.42815 (12)0.0616 (7)
H17A0.08880.03640.45240.074*
H17B0.17620.20110.43940.074*
C170.3228 (3)0.0043 (4)0.42063 (14)0.0686 (8)
H18A0.41130.07350.41950.082*
H18B0.32890.08210.44710.082*
N10.1609 (2)0.0694 (2)0.36736 (9)0.0457 (5)
N20.35756 (18)0.5030 (2)0.42793 (7)0.0351 (4)
O10.38424 (18)0.74030 (19)0.47069 (7)0.0496 (4)
O20.0512 (3)0.0306 (2)0.27960 (8)0.0689 (6)
O30.08117 (19)0.19746 (19)0.35635 (9)0.0595 (5)
F10.5958 (3)0.7614 (3)0.20283 (8)0.0956 (7)
F20.78369 (17)0.4820 (2)0.36687 (8)0.0728 (5)
S20.00544 (6)0.05936 (7)0.33804 (2)0.0439 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0383 (11)0.0416 (13)0.0557 (14)0.0018 (9)0.0115 (10)0.0043 (10)
C60.0371 (10)0.0311 (10)0.0421 (11)0.0042 (8)0.0083 (9)0.0032 (8)
C50.0438 (12)0.0515 (14)0.0535 (14)0.0057 (10)0.0137 (10)0.0076 (11)
C40.0662 (16)0.0605 (16)0.0530 (14)0.0034 (13)0.0103 (12)0.0172 (12)
C30.0729 (17)0.0577 (16)0.0481 (14)0.0133 (13)0.0197 (12)0.0055 (12)
C20.0581 (14)0.0542 (15)0.0678 (17)0.0120 (12)0.0321 (13)0.0068 (13)
C130.0394 (11)0.0356 (11)0.0408 (11)0.0024 (9)0.0056 (9)0.0033 (9)
C120.0475 (12)0.0318 (11)0.0494 (13)0.0023 (9)0.0024 (10)0.0060 (9)
C110.0396 (10)0.0384 (12)0.0411 (11)0.0002 (9)0.0021 (9)0.0051 (9)
C100.0327 (10)0.0326 (11)0.0373 (10)0.0003 (8)0.0074 (8)0.0001 (8)
C140.0404 (11)0.0413 (12)0.0412 (11)0.0013 (9)0.0021 (9)0.0025 (9)
C150.0404 (11)0.0346 (11)0.0463 (12)0.0024 (9)0.0013 (9)0.0055 (9)
C160.0453 (13)0.0574 (17)0.092 (2)0.0090 (12)0.0002 (14)0.0004 (14)
C80.0399 (11)0.0355 (12)0.0352 (10)0.0009 (9)0.0029 (8)0.0033 (9)
C90.0464 (12)0.0544 (14)0.0551 (14)0.0036 (11)0.0156 (11)0.0045 (11)
C70.0310 (10)0.0428 (12)0.0466 (12)0.0017 (8)0.0056 (9)0.0045 (9)
C180.0587 (15)0.0660 (17)0.0618 (16)0.0032 (13)0.0146 (13)0.0028 (13)
C170.0558 (15)0.0649 (18)0.088 (2)0.0014 (13)0.0218 (15)0.0165 (16)
N10.0413 (10)0.0402 (11)0.0541 (12)0.0020 (8)0.0009 (9)0.0068 (8)
N20.0316 (8)0.0346 (9)0.0395 (9)0.0028 (7)0.0068 (7)0.0008 (7)
O10.0548 (9)0.0397 (9)0.0534 (10)0.0071 (7)0.0036 (8)0.0062 (7)
O20.0911 (14)0.0710 (13)0.0438 (10)0.0216 (11)0.0058 (9)0.0158 (9)
O30.0549 (10)0.0342 (9)0.0909 (14)0.0033 (7)0.0156 (9)0.0119 (9)
F10.1171 (15)0.1121 (16)0.0652 (11)0.0096 (12)0.0409 (11)0.0288 (10)
F20.0422 (8)0.0833 (12)0.0961 (13)0.0171 (8)0.0213 (8)0.0172 (9)
S20.0484 (4)0.0368 (4)0.0468 (4)0.0036 (2)0.0076 (3)0.0109 (2)
Geometric parameters (Å, º) top
C1—F21.359 (3)C15—H120.9300
C1—C21.375 (4)C16—N11.479 (3)
C1—C61.381 (3)C16—C171.516 (5)
C6—C51.382 (3)C16—H13A0.9700
C6—C71.502 (3)C16—H13B0.9700
C5—C41.383 (4)C8—O11.223 (3)
C5—H30.9300C8—N21.356 (3)
C4—C31.369 (4)C8—C91.499 (3)
C4—H40.9300C9—H15A0.9600
C3—F11.350 (3)C9—H15B0.9600
C3—C21.362 (4)C9—H15C0.9600
C2—H60.9300C7—N21.463 (3)
C13—C141.386 (3)C7—H7A0.9700
C13—C121.388 (3)C7—H7B0.9700
C13—S21.766 (2)C18—N11.470 (3)
C12—C111.376 (3)C18—C171.527 (4)
C12—H80.9300C18—H17A0.9700
C11—C101.393 (3)C18—H17B0.9700
C11—H90.9300C17—H18A0.9700
C10—C151.384 (3)C17—H18B0.9700
C10—N21.439 (3)N1—S21.612 (2)
C14—C151.380 (3)O2—S21.419 (2)
C14—H110.9300O3—S21.4296 (18)
F2—C1—C2118.4 (2)H13A—C16—H13B111.1
F2—C1—C6117.2 (2)O1—C8—N2121.09 (19)
C2—C1—C6124.5 (2)O1—C8—C9121.4 (2)
C1—C6—C5116.1 (2)N2—C8—C9117.43 (19)
C1—C6—C7119.94 (19)C8—C9—H15A109.5
C5—C6—C7123.92 (19)C8—C9—H15B109.5
C6—C5—C4121.6 (2)H15A—C9—H15B109.5
C6—C5—H3119.2C8—C9—H15C109.5
C4—C5—H3119.2H15A—C9—H15C109.5
C3—C4—C5118.5 (2)H15B—C9—H15C109.5
C3—C4—H4120.7N2—C7—C6114.27 (17)
C5—C4—H4120.7N2—C7—H7A108.7
F1—C3—C2118.8 (2)C6—C7—H7A108.7
F1—C3—C4118.3 (3)N2—C7—H7B108.7
C2—C3—C4122.9 (2)C6—C7—H7B108.7
C3—C2—C1116.3 (2)H7A—C7—H7B107.6
C3—C2—H6121.8N1—C18—C1788.7 (2)
C1—C2—H6121.8N1—C18—H17A113.9
C14—C13—C12120.43 (19)C17—C18—H17A113.9
C14—C13—S2119.25 (16)N1—C18—H17B113.9
C12—C13—S2120.32 (17)C17—C18—H17B113.9
C11—C12—C13119.6 (2)H17A—C18—H17B111.1
C11—C12—H8120.2C16—C17—C1887.9 (2)
C13—C12—H8120.2C16—C17—H18A114.0
C12—C11—C10119.96 (19)C18—C17—H18A114.0
C12—C11—H9120.0C16—C17—H18B114.0
C10—C11—H9120.0C18—C17—H18B114.0
C15—C10—C11120.28 (19)H18A—C17—H18B111.2
C15—C10—N2120.25 (18)C18—N1—C1691.5 (2)
C11—C10—N2119.41 (17)C18—N1—S2125.64 (16)
C15—C14—C13119.97 (19)C16—N1—S2126.87 (18)
C15—C14—H11120.0C8—N2—C10123.67 (16)
C13—C14—H11120.0C8—N2—C7118.69 (17)
C14—C15—C10119.72 (19)C10—N2—C7117.64 (17)
C14—C15—H12120.1O2—S2—O3120.79 (12)
C10—C15—H12120.1O2—S2—N1106.48 (12)
N1—C16—C1788.8 (2)O3—S2—N1105.75 (11)
N1—C16—H13A113.8O2—S2—C13107.50 (11)
C17—C16—H13A113.8O3—S2—C13107.47 (10)
N1—C16—H13B113.8N1—S2—C13108.35 (10)
C17—C16—H13B113.8
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H3···O3i0.932.443.336 (3)162
C11—H9···O1ii0.932.513.406 (3)162
C17—H18B···O1iii0.972.563.509 (4)166
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+1; (iii) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC18H18F2N2O3S
Mr380.40
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)8.7793 (15), 8.4442 (15), 23.810 (4)
β (°) 97.312 (6)
V3)1750.8 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.22 × 0.21 × 0.20
Data collection
DiffractometerBruker SMART CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.000, 0.001
No. of measured, independent and
observed [I > 2σ(I)] reflections
14668, 3077, 2684
Rint0.036
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.143, 1.04
No. of reflections3077
No. of parameters236
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.38

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H3···O3i0.932.443.336 (3)162
C11—H9···O1ii0.932.513.406 (3)162
C17—H18B···O1iii0.972.563.509 (4)166
Symmetry codes: (i) x, y+1, z; (ii) x+1, y+1, z+1; (iii) x, y+1, z+1.
 

Acknowledgements

This work was partially supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (SRFDP20110182110007), the Research Funds for the Central Universities (XDJK2012B026) and the National Innovative Training Program for College Students.

References

First citationBruker (2001). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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