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Acta Crystallogr Sect E Struct Rep Online. 2008 February 1; 64(Pt 2): o441.
Published online 2008 January 16. doi:  10.1107/S1600536808000421
PMCID: PMC2960169

1-Ethyl-6-fluoro-7-(4-methyl­piperazin-4-ium-1-yl)-4-oxo-1,4-dihydroquinoline-3-carboxylate hexa­hydrate

Abstract

In the title compound, C17H20FN3O3·6H2O, the pefloxacin (pef) neutral zwitterion is accompanied by six water mol­ecules of hydration. An extensive network of O—H(...)O and N—H(...)O hydrogen bonds help to establish the crystal packing.

Related literature

For metal complexes of the pef anion, see: Baenziger et al. (1986 [triangle]); An, Huang & Qi (2007 [triangle]); An, Qi & Huang (2007 [triangle]). For background on the medicinal uses of Hpef, see: Mizuki et al. (1996 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-0o441-scheme1.jpg

Experimental

Crystal data

  • C17H20FN3O3·6H2O
  • M r = 441.46
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o441-efi1.jpg
  • a = 8.0925 (15) Å
  • b = 24.075 (5) Å
  • c = 10.8006 (19) Å
  • β = 92.064 (3)°
  • V = 2102.9 (7) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.12 mm−1
  • T = 296 (2) K
  • 0.34 × 0.26 × 0.18 mm

Data collection

  • Bruker SMART CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 1998 [triangle]) T min = 0.960, T max = 0.978
  • 10920 measured reflections
  • 3743 independent reflections
  • 2239 reflections with I > 2σ(I)
  • R int = 0.051

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.134
  • S = 1.02
  • 3743 reflections
  • 312 parameters
  • 19 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.22 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: SMART (Bruker, 1998 [triangle]); cell refinement: SAINT-Plus (Bruker, 1998 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Bruker, 1998 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808000421/hb2680sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808000421/hb2680Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge financial support by the Science Foundation of Heilongjiang Provincial Department of Science & Technology (grant No. GC07C35204).

supplementary crystallographic information

Comment

Pefloxacin (Hpef, C17H20FN3O3, 1-ethyl-6-fluoro-7-(4-methylpiperazin-1-yl)-4-oxo-quinoline -3-carboxylic acid) is member of a class of quinolones used to treat infections (Mizuki et al., 1996). The silver(I), manganese(II) and cobalt(II) derivatives of the pefloxacin (pef) anion have been reported (Baenziger et al., 1986; An, Huang & Qi, 2007; An, Qi & Huang, 2007).

We attempted to prepare a nickel(II) complex of pef, but the title compound, (I), arose instead. The neutral Hpef zwitterion shows nominal proton transfer from O1 or O2 to N3. Consequently the C1—O1 [1.264 (3) Å] and C1—O2 [1.245 (3) Å] bond lengths are very similar. The bond angle sum for N1 of 360° indicates sp2 hybridization for this atom. The N2/N3/C11—C14 ring is a typical chair.

The components of (I) are linked by O—H···O and O—H···N hydrogen bonds (Table 1) involving all the potential donors, generating a three-dimensional supramolecular network.

Experimental

A mixture of Ni(NO3)2.6H2O (0.075 g, 0.25 mmol), Hpef (0.17 g, 0.5 mmol), and water (12 ml) was stirred for 30 min in air. The mixture was then transferred to a 23 ml Teflon-lined hydrothermal bomb. The bomb was kept at 423 K for 72 h under autogenous pressure. The targeted Ni2+ complex was not synthesized and colorless prisms of (I) were obtained from the reaction mixture after cooling.

Refinement

The carbon-bound H atoms were positioned geometrically (C—H = 0.93–0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = 1.2Ueq(C). The O– and N-bonded H atoms were located in a difference map, and were refined with a distance restraint of N—H = 0.90 (1) /%A and with Uiso(H) = 1.5Ueq(N) and O—H = 0.85 (1) /%A and with Uiso(H) = 1.5Ueq(O). Some short intermolecular H···H contacts occur; thus, the H atom positions of the water molecules should be regarded as less reliable.

Figures

Fig. 1.
The asymmetric unit of (I), showing 50% displacement ellipsoids.

Crystal data

C17H20FN3O3·6H2OF000 = 944
Mr = 441.46Dx = 1.394 Mg m3
Monoclinic, P21/nMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 10069 reflections
a = 8.0925 (15) Åθ = 2.1–25.1º
b = 24.075 (5) ŵ = 0.12 mm1
c = 10.8006 (19) ÅT = 296 (2) K
β = 92.064 (3)ºPrism, colorless
V = 2102.9 (7) Å30.34 × 0.26 × 0.18 mm
Z = 4

Data collection

Bruker SMART CCD diffractometer3743 independent reflections
Radiation source: fine-focus sealed tube2239 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.051
T = 295(2) Kθmax = 25.1º
ω scansθmin = 2.1º
Absorption correction: multi-scan(SADABS; Bruker, 1998)h = −9→9
Tmin = 0.960, Tmax = 0.978k = −25→28
10920 measured reflectionsl = −8→12

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.134  w = 1/[σ2(Fo2) + (0.0593P)2 + 0.0315P] where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
3743 reflectionsΔρmax = 0.22 e Å3
312 parametersΔρmin = −0.20 e Å3
19 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods

Special details

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.

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

xyzUiso*/Ueq
F10.4982 (2)0.12293 (6)0.56081 (13)0.0524 (5)
O10.9475 (3)−0.18675 (8)0.62111 (17)0.0512 (5)
O20.9816 (3)−0.13364 (8)0.78658 (17)0.0548 (6)
O30.7598 (2)−0.04158 (7)0.76314 (16)0.0436 (5)
O1W1.0319 (4)−0.28815 (9)0.7094 (2)0.0761 (7)
H1W11.010 (5)−0.2538 (6)0.695 (3)0.114*
H1W21.104 (4)−0.2906 (13)0.768 (3)0.114*
O2W1.0567 (3)−0.19330 (10)0.9952 (2)0.0687 (7)
H2W11.042 (4)−0.1772 (13)0.9256 (17)0.103*
H2W21.121 (4)−0.1734 (12)1.042 (2)0.103*
O3W1.2764 (3)−0.26876 (9)0.92250 (17)0.0558 (6)
H3W21.318 (4)−0.2872 (11)0.9835 (19)0.084*
H3W11.204 (3)−0.2460 (12)0.950 (2)0.084*
O4W0.6261 (3)0.02774 (10)0.9339 (2)0.0637 (6)
O5W1.0677 (3)−0.04707 (12)0.9484 (2)0.0817 (8)
H5W11.022 (4)−0.0705 (13)0.899 (3)0.123*
H5W20.997 (3)−0.0308 (15)0.990 (4)0.123*
O6W1.2719 (3)−0.13973 (11)1.1601 (3)0.0914 (9)
H6W11.360 (3)−0.1585 (13)1.176 (4)0.137*
H6W21.298 (5)−0.1066 (7)1.143 (4)0.137*
N10.8676 (2)−0.05154 (8)0.39571 (18)0.0325 (5)
N20.5711 (3)0.12232 (8)0.31502 (18)0.0351 (5)
N30.4587 (3)0.20866 (9)0.1516 (2)0.0399 (6)
H3N0.552 (2)0.2224 (11)0.119 (2)0.060*
C10.9405 (3)−0.14034 (11)0.6754 (3)0.0361 (6)
C20.8807 (3)−0.09193 (10)0.6006 (2)0.0318 (6)
C30.7935 (3)−0.04596 (10)0.6512 (2)0.0320 (6)
C40.7415 (3)−0.00337 (10)0.5619 (2)0.0303 (6)
C50.6494 (3)0.04228 (10)0.6011 (2)0.0350 (6)
H50.62340.04540.68400.042*
C60.5981 (3)0.08168 (11)0.5202 (2)0.0354 (6)
C70.6356 (3)0.08101 (11)0.3938 (2)0.0327 (6)
C80.7274 (3)0.03613 (10)0.3540 (2)0.0318 (6)
H80.75560.03410.27140.038*
C90.7785 (3)−0.00614 (10)0.4361 (2)0.0294 (6)
C100.9112 (3)−0.09195 (10)0.4773 (2)0.0337 (6)
H100.9671−0.12250.44670.040*
C110.6038 (3)0.18058 (10)0.3458 (2)0.0404 (7)
H11B0.71000.19160.31490.048*
H11A0.60760.18530.43510.048*
C120.4696 (4)0.21632 (11)0.2885 (2)0.0422 (7)
H12B0.36460.20670.32330.051*
H12A0.49240.25500.30760.051*
C130.4413 (3)0.14871 (11)0.1185 (2)0.0390 (7)
H13B0.44750.14450.02950.047*
H13A0.33380.13550.14240.047*
C140.5745 (3)0.11382 (11)0.1818 (2)0.0391 (7)
H14B0.55600.07490.16270.047*
H14A0.68180.12430.15220.047*
C150.3210 (4)0.24236 (14)0.0946 (3)0.0607 (9)
H15A0.31800.23740.00640.091*
H15B0.33870.28090.11380.091*
H15C0.21790.23050.12700.091*
C160.9107 (3)−0.05917 (12)0.2649 (2)0.0390 (7)
H16B1.0083−0.08240.26170.047*
H16A0.9375−0.02330.22990.047*
C170.7735 (4)−0.08525 (15)0.1874 (3)0.0642 (10)
H17A0.7489−0.12130.21980.096*
H17B0.8072−0.08880.10350.096*
H17C0.6766−0.06230.18950.096*
H4W10.657 (4)0.0071 (13)0.874 (2)0.096*
H4W20.709 (3)0.0325 (14)0.984 (2)0.096*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
F10.0657 (11)0.0498 (11)0.0420 (10)0.0227 (9)0.0072 (8)−0.0003 (7)
O10.0692 (14)0.0320 (12)0.0515 (13)0.0057 (10)−0.0116 (10)0.0010 (9)
O20.0748 (15)0.0505 (13)0.0380 (13)0.0082 (11)−0.0155 (10)0.0037 (9)
O30.0604 (13)0.0411 (12)0.0293 (11)0.0039 (10)0.0017 (9)0.0017 (8)
O1W0.097 (2)0.0451 (14)0.0843 (19)−0.0009 (14)−0.0253 (14)0.0077 (12)
O2W0.0744 (18)0.0650 (16)0.0660 (16)0.0009 (13)−0.0099 (13)0.0230 (12)
O3W0.0567 (15)0.0574 (15)0.0531 (14)−0.0038 (11)−0.0015 (10)0.0151 (10)
O4W0.0667 (15)0.0719 (17)0.0519 (15)0.0112 (13)−0.0060 (11)−0.0213 (11)
O5W0.091 (2)0.081 (2)0.0720 (19)−0.0046 (16)−0.0108 (14)−0.0229 (12)
O6W0.107 (2)0.0690 (18)0.096 (2)0.0147 (16)−0.0310 (17)−0.0081 (16)
N10.0363 (13)0.0324 (12)0.0290 (12)0.0011 (10)0.0018 (9)−0.0018 (10)
N20.0484 (14)0.0282 (12)0.0280 (12)−0.0011 (11)−0.0074 (10)−0.0007 (9)
N30.0408 (15)0.0389 (14)0.0400 (14)0.0036 (11)0.0015 (11)0.0076 (10)
C10.0346 (16)0.0341 (16)0.0395 (17)−0.0036 (13)−0.0005 (12)0.0017 (13)
C20.0330 (15)0.0322 (15)0.0298 (15)−0.0020 (12)−0.0040 (11)0.0008 (11)
C30.0324 (15)0.0327 (15)0.0305 (15)−0.0051 (12)−0.0031 (11)−0.0002 (12)
C40.0325 (15)0.0285 (14)0.0295 (14)−0.0049 (12)−0.0025 (11)−0.0001 (11)
C50.0409 (16)0.0380 (16)0.0258 (14)0.0016 (13)−0.0013 (11)−0.0029 (12)
C60.0377 (16)0.0359 (16)0.0325 (15)0.0056 (13)−0.0003 (12)−0.0046 (12)
C70.0316 (14)0.0332 (15)0.0327 (15)−0.0062 (12)−0.0045 (11)0.0026 (12)
C80.0338 (15)0.0317 (15)0.0299 (14)−0.0024 (12)0.0026 (11)0.0000 (11)
C90.0278 (14)0.0304 (14)0.0299 (14)−0.0053 (12)0.0009 (11)−0.0011 (11)
C100.0340 (15)0.0266 (14)0.0405 (16)0.0019 (12)−0.0015 (12)−0.0020 (12)
C110.0492 (18)0.0333 (16)0.0378 (16)−0.0046 (14)−0.0090 (12)−0.0014 (12)
C120.0522 (19)0.0367 (16)0.0379 (17)0.0030 (14)0.0035 (13)−0.0014 (12)
C130.0450 (17)0.0415 (17)0.0304 (15)−0.0026 (14)−0.0021 (12)0.0020 (12)
C140.0504 (17)0.0338 (16)0.0329 (16)0.0014 (13)−0.0010 (12)0.0005 (12)
C150.053 (2)0.061 (2)0.068 (2)0.0162 (17)−0.0062 (16)0.0190 (16)
C160.0476 (17)0.0404 (16)0.0294 (15)0.0017 (13)0.0086 (12)−0.0007 (12)
C170.073 (2)0.077 (2)0.0430 (19)−0.019 (2)0.0019 (16)−0.0111 (16)

Geometric parameters (Å, °)

F1—C61.363 (3)C3—C41.459 (3)
C1—O11.264 (3)C4—C51.402 (3)
C1—O21.245 (3)C4—C91.404 (3)
C3—O31.253 (3)C5—C61.345 (3)
O1W—H1W10.857 (10)C5—H50.9300
O1W—H1W20.85 (3)C6—C71.409 (3)
O2W—H2W10.851 (10)C7—C81.388 (3)
O2W—H2W20.86 (3)C8—C91.402 (3)
O3W—H3W20.852 (10)C8—H80.9300
O3W—H3W10.86 (3)C10—H100.9300
O4W—H4W10.86 (3)C11—C121.501 (4)
O4W—H4W20.851 (10)C11—H11B0.9700
O5W—H5W10.85 (3)C11—H11A0.9700
O5W—H5W20.84 (3)C12—H12B0.9700
O6W—H6W10.86 (3)C12—H12A0.9700
O6W—H6W20.847 (10)C13—C141.510 (4)
N1—C101.351 (3)C13—H13B0.9700
N1—C91.388 (3)C13—H13A0.9700
N1—C161.479 (3)C14—H14B0.9700
N2—C71.397 (3)C14—H14A0.9700
N2—C141.454 (3)C15—H15A0.9600
N2—C111.463 (3)C15—H15B0.9600
N3—C121.490 (3)C15—H15C0.9600
N3—C131.492 (3)C16—C171.504 (4)
N3—C151.493 (3)C16—H16B0.9700
N3—H3N0.910 (10)C16—H16A0.9700
C1—C21.489 (4)C17—H17A0.9600
C2—C101.363 (3)C17—H17B0.9600
C2—C31.431 (3)C17—H17C0.9600
H1W1—O1W—H1W2109.3 (17)N1—C10—C2125.8 (2)
H2W1—O2W—H2W2109.4 (16)N1—C10—H10117.1
H3W2—O3W—H3W1108.6 (16)C2—C10—H10117.1
H4W1—O4W—H4W2108.2 (16)N2—C11—C12109.5 (2)
H5W1—O5W—H5W2110.9 (18)N2—C11—H11B109.8
H6W1—O6W—H6W2109.4 (17)C12—C11—H11B109.8
C10—N1—C9119.2 (2)N2—C11—H11A109.8
C10—N1—C16118.0 (2)C12—C11—H11A109.8
C9—N1—C16122.7 (2)H11B—C11—H11A108.2
C7—N2—C14118.8 (2)N3—C12—C11110.8 (2)
C7—N2—C11118.89 (19)N3—C12—H12B109.5
C14—N2—C11110.49 (19)C11—C12—H12B109.5
C12—N3—C13111.04 (19)N3—C12—H12A109.5
C12—N3—C15111.0 (2)C11—C12—H12A109.5
C13—N3—C15111.4 (2)H12B—C12—H12A108.1
C12—N3—H3N108.4 (19)N3—C13—C14111.7 (2)
C13—N3—H3N109.5 (19)N3—C13—H13B109.3
C15—N3—H3N105.3 (19)C14—C13—H13B109.3
O2—C1—O1123.2 (2)N3—C13—H13A109.3
O2—C1—C2119.5 (2)C14—C13—H13A109.3
O1—C1—C2117.3 (2)H13B—C13—H13A107.9
C10—C2—C3118.9 (2)N2—C14—C13109.3 (2)
C10—C2—C1117.6 (2)N2—C14—H14B109.8
C3—C2—C1123.6 (2)C13—C14—H14B109.8
O3—C3—C2124.1 (2)N2—C14—H14A109.8
O3—C3—C4120.7 (2)C13—C14—H14A109.8
C2—C3—C4115.2 (2)H14B—C14—H14A108.3
C5—C4—C9117.6 (2)N3—C15—H15A109.5
C5—C4—C3119.7 (2)N3—C15—H15B109.5
C9—C4—C3122.7 (2)H15A—C15—H15B109.5
C6—C5—C4120.8 (2)N3—C15—H15C109.5
C6—C5—H5119.6H15A—C15—H15C109.5
C4—C5—H5119.6H15B—C15—H15C109.5
C5—C6—F1118.5 (2)N1—C16—C17112.9 (2)
C5—C6—C7123.3 (2)N1—C16—H16B109.0
F1—C6—C7118.1 (2)C17—C16—H16B109.0
C8—C7—N2123.9 (2)N1—C16—H16A109.0
C8—C7—C6116.4 (2)C17—C16—H16A109.0
N2—C7—C6119.5 (2)H16B—C16—H16A107.8
C7—C8—C9121.2 (2)C16—C17—H17A109.5
C7—C8—H8119.4C16—C17—H17B109.5
C9—C8—H8119.4H17A—C17—H17B109.5
N1—C9—C8121.2 (2)C16—C17—H17C109.5
N1—C9—C4118.2 (2)H17A—C17—H17C109.5
C8—C9—C4120.6 (2)H17B—C17—H17C109.5
O2—C1—C2—C10149.2 (3)C10—N1—C9—C8−178.5 (2)
O1—C1—C2—C10−30.5 (3)C16—N1—C9—C8−1.6 (3)
O2—C1—C2—C3−30.8 (4)C10—N1—C9—C41.9 (3)
O1—C1—C2—C3149.5 (2)C16—N1—C9—C4178.8 (2)
C10—C2—C3—O3−179.6 (2)C7—C8—C9—N1178.8 (2)
C1—C2—C3—O30.5 (4)C7—C8—C9—C4−1.7 (3)
C10—C2—C3—C41.5 (3)C5—C4—C9—N1−179.1 (2)
C1—C2—C3—C4−178.4 (2)C3—C4—C9—N10.3 (3)
O3—C3—C4—C5−1.5 (3)C5—C4—C9—C81.3 (3)
C2—C3—C4—C5177.4 (2)C3—C4—C9—C8−179.3 (2)
O3—C3—C4—C9179.1 (2)C9—N1—C10—C2−2.5 (4)
C2—C3—C4—C9−2.0 (3)C16—N1—C10—C2−179.6 (2)
C9—C4—C5—C60.3 (4)C3—C2—C10—N10.6 (4)
C3—C4—C5—C6−179.1 (2)C1—C2—C10—N1−179.4 (2)
C4—C5—C6—F1175.0 (2)C7—N2—C11—C12−154.7 (2)
C4—C5—C6—C7−1.7 (4)C14—N2—C11—C1262.7 (3)
C14—N2—C7—C811.0 (4)C13—N3—C12—C1153.2 (3)
C11—N2—C7—C8−128.5 (3)C15—N3—C12—C11177.7 (2)
C14—N2—C7—C6−164.6 (2)N2—C11—C12—N3−58.1 (3)
C11—N2—C7—C656.0 (3)C12—N3—C13—C14−52.3 (3)
C5—C6—C7—C81.3 (4)C15—N3—C13—C14−176.6 (2)
F1—C6—C7—C8−175.4 (2)C7—N2—C14—C13156.2 (2)
C5—C6—C7—N2177.2 (2)C11—N2—C14—C13−61.2 (3)
F1—C6—C7—N20.4 (3)N3—C13—C14—N256.0 (3)
N2—C7—C8—C9−175.3 (2)C10—N1—C16—C1793.5 (3)
C6—C7—C8—C90.4 (3)C9—N1—C16—C17−83.4 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1W—H1W1···O10.857 (10)1.866 (12)2.700 (3)164 (3)
O1W—H1W2···O3W0.85 (3)2.201 (16)3.017 (3)162 (3)
O2W—H2W1···O20.851 (10)1.881 (13)2.722 (3)170 (4)
O2W—H2W2···O6W0.86 (3)1.91 (3)2.765 (3)171 (3)
O3W—H3W2···O1i0.852 (10)1.896 (13)2.730 (3)166 (3)
O3W—H3W1···O2W0.86 (3)1.82 (3)2.679 (3)175 (3)
O6W—H6W1···O1Wi0.86 (3)1.92 (3)2.765 (4)170 (4)
O6W—H6W2···O4Wii0.847 (10)2.17 (3)3.007 (4)170 (4)
N3—H3N···O3Wiii0.910 (10)1.847 (13)2.730 (3)163 (3)
O4W—H4W1···O30.86 (3)1.89 (3)2.739 (3)169 (3)
O4W—H4W2···O5Wii0.85 (3)1.959 (15)2.783 (3)163 (3)
O5W—H5W1···O20.85 (3)1.97 (3)2.792 (3)164 (4)
O5W—H5W1···O30.85 (3)2.63 (4)3.142 (3)120 (3)
O5W—H5W2···O5Wii0.84 (3)2.06 (2)2.769 (5)142 (3)

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB2680).

References

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