organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Butallyl­onal 1,4-dioxane hemisolvate

aInstitute of Pharmacy, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
*Correspondence e-mail: thomas.gelbrich@uibk.ac.at

(Received 15 September 2010; accepted 27 September 2010; online 30 September 2010)

The asymmetric unit of the title compound [systematic name: 5-(1-bromo­prop-2-en-1-yl)-5-sec-butyl­pyrimidine-2,4,6-trione 1,4-dioxane hemisolvate], C11H15BrN2O3·0.5C4H8O2, contains one half-mol­ecule of 1,4-dioxane and one mol­ecule of butallyl­onal, with an almost planar barbiturate ring [largest deviation from the mean plane = 0.049 (5) Å]. The centrosymmetric dioxane mol­ecule adopts a nearly ideal chair conformation. The barbiturate mol­ecules are linked together by an N—H⋯O hydrogen bond, giving a single-stranded chain. Additionally, each dioxane mol­ecule acts as a bridge between two anti­parallel strands of hydrogen-bonded barbiturate mol­ecules via two hydrogen bonds, N—H⋯O(dioxane)O⋯H—N. Thus, a ladder structure is obtained, with the connected barbiturate mol­ecules forming the `stiles' and the bridging dioxane mol­ecules the `rungs'.

Related literature

For the preparation of butallyl­onal, see: J. D. Riedel Akt.-Ges. (1924[J. D. Riedel Akt.-Ges. (1924). GB Patent 244122.]); Boedecker (1929[Boedecker, F. (1929). US Patent 1739662]). For related structures, see: Al-Saqqar et al. (2004[Al-Saqqar, S., Falvello, L. R. & Soler, T. (2004). J. Chem. Crystallogr. 34, 61-65.]); Gelbrich et al. (2007[Gelbrich, T., Zencirci, N. & Griesser, U. J. (2007). Acta Cryst. C63, o751-o753.], 2010[Gelbrich, T., Rossi, D. & Griesser, U. J. (2010). Acta Cryst. E66, o1219.]); Craven et al. (1969[Craven, B. M., Vizzini, E. A. & Rodrigues, M. M. (1969). Acta Cryst. B25, 1978-1993.]); Gatehouse & Craven (1971[Gatehouse, B. M. & Craven, B. M. (1971). Acta Cryst. B27, 1337-1344.]); Lewis et al. (2004[Lewis, T. C., Tocher, D. A. & Price, S. L. (2004). Cryst. Growth Des. 4, 979-987.]); Zencirci et al. (2009[Zencirci, N., Gelbrich, T., Kahlenberg, V. & Griesser, U. J. (2009). Cryst. Growth Des. 9, 3444-3456.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C11H15BrN2O3·0.5C4H8O2

  • Mr = 347.21

  • Monoclinic, P 21 /n

  • a = 10.494 (2) Å

  • b = 6.7679 (8) Å

  • c = 21.864 (3) Å

  • β = 97.294 (15)°

  • V = 1540.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.68 mm−1

  • T = 293 K

  • 0.25 × 0.08 × 0.07 mm

Data collection
  • Oxford Diffraction Xcalibur Ruby Gemini ultra diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.990, Tmax = 1.000

  • 9189 measured reflections

  • 2714 independent reflections

  • 1171 reflections with I > 2σ(I)

  • Rint = 0.100

Refinement
  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.145

  • S = 0.95

  • 2714 reflections

  • 189 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.56 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O4i 0.88 (1) 1.98 (2) 2.837 (5) 166 (6)
N3—H3⋯O1S 0.89 (4) 1.87 (4) 2.757 (6) 177 (5)
Symmetry code: (i) x, y+1, z.

Data collection: CrysAlis PRO (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: XP in SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and Mercury (Bruno et al., 2002[Bruno, I. J., Cole, J. C., Edgington, P. R., Kessler, M., Macrae, C. F., McCabe, P., Pearson, J. & Taylor, R. (2002). Acta Cryst. B58, 389-397.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

5,5-Dihydroxybarbituric acid (alternative names: butallylonal, butylalylonal, pernocton, pernoston, sonbutal; CAS number 1142–70-7) has been used as a sedative drug since the 1920s, mainly as an anaesthetic in veterinary medicine. The asymmetric unit of the title compound contains one butallylonal molecule exhibiting an almost planar barbiturate ring [where atom C6 shows the largest deviation from the mean plane, 0.049 (5) Å] and half a molecule of 1,4-dioxane. The two torsion angles of the C8—C7—C5—C10—C14 chain are trans, C7—C5—C10—C12 is gauche and C5—C10—C14 trans (see Fig. 1). The centrosymmetric dioxane molecule adopts a near-to-ideal chair conformation.

The barbiturate molecules are linked together by one N—H···O bond to give a single-stranded chain. Additionally, each dioxane molecule acts as a bridge between two antiparallel strands of H-bonded barbiturate molecules. This interaction involves two hydrogen bonds, N—H···O(dioxane)O···H—N. Overall, a ladder structure is generated, which propagates parallel to the b axis (see Fig. 2). The stiles of the ladder are formed by the connected barbiturate molecules and its rungs by the bridging dioxane molecules. This H-bonded structure is reminiscent of the ladder motif observed in single component structures of several barbiturates, see Craven et al. (1969); Gatehouse & Craven (1971); Lewis et al. (2004); Gelbrich et al. (2007); Zencirci et al. (2009). The main difference to the title structure is that in these cases, a second C=O group participates in hydrogen bonding so that two antiparallel strands of H-bonded barbiturate molecules are linked together directly via centrosymmetric R22(8) rings (Bernstein et al., 1995).

Related literature top

For the preparation of butallylonal, see: J. D. Riedel Akt.-Ges. (1924); Boedecker (1929). For related structures, see: Al-Saqqar et al. (2004); Gelbrich et al. (2007, 2010); Craven et al. (1969); Gatehouse & Craven (1971); Lewis et al. (2004); Zencirci et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

A solution of butallylonal ("Pernocton"; J. D. Riedel - E. de Haën AG, Berlin) in 1,4-dioxane was filled into an NMR tube and left for evaporation. Colourless crystals of the title compound were obtained after several weeks.

Refinement top

All H atoms were identified in a difference map. H atoms bonded to C atoms were positioned geometrically and refined with Uiso(H) = 1.2 Ueq(C). Hydrogen atoms attached to N were refined with restrained distances [N—H = 0.88 (2) Å], and their Uiso parameters were refined freely.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and Mercury (Bruno et al., 2002); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structures of (I) with displacement ellipsoids drawn at the 30% probability level. Hydrogen atoms are shown as spheres of arbitrary size. Symmetry code: (i) -x, -y, -z.
[Figure 2] Fig. 2. A portion of the one-dimensional hydrogen bonded ladder structure which consists of two antiparallel strands of singly N–H···O bonded barbiturate molecules, which are bridged by dioxane molecules, N–H···O(dioxane)O···H–N. The structure is viewed parallel to the c-axis. O and H atoms involved in hydrogen bonding ar drawn as balls.
5-(1-bromoprop-2-en-1-yl)-5-sec-butylpyrimidine-2,4,6-trione 1,4-dioxane hemisolvate top
Crystal data top
C11H15BrN2O3·0.5C4H8O2F(000) = 712
Mr = 347.21Dx = 1.497 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 837 reflections
a = 10.494 (2) Åθ = 2.5–28.5°
b = 6.7679 (8) ŵ = 2.68 mm1
c = 21.864 (3) ÅT = 293 K
β = 97.294 (15)°Prism, colourless
V = 1540.3 (4) Å30.25 × 0.08 × 0.07 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur Ruby Gemini ultra
diffractometer
2714 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source1171 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.100
Detector resolution: 10.3575 pixels mm-1θmax = 25.1°, θmin = 3.2°
ω scansh = 1012
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2007)
k = 88
Tmin = 0.990, Tmax = 1.000l = 2526
9189 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H atoms treated by a mixture of independent and constrained refinement
S = 0.95 w = 1/[σ2(Fo2) + (0.0409P)2]
where P = (Fo2 + 2Fc2)/3
2714 reflections(Δ/σ)max < 0.001
189 parametersΔρmax = 0.56 e Å3
2 restraintsΔρmin = 0.33 e Å3
Crystal data top
C11H15BrN2O3·0.5C4H8O2V = 1540.3 (4) Å3
Mr = 347.21Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.494 (2) ŵ = 2.68 mm1
b = 6.7679 (8) ÅT = 293 K
c = 21.864 (3) Å0.25 × 0.08 × 0.07 mm
β = 97.294 (15)°
Data collection top
Oxford Diffraction Xcalibur Ruby Gemini ultra
diffractometer
2714 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2007)
1171 reflections with I > 2σ(I)
Tmin = 0.990, Tmax = 1.000Rint = 0.100
9189 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0642 restraints
wR(F2) = 0.145H atoms treated by a mixture of independent and constrained refinement
S = 0.95Δρmax = 0.56 e Å3
2714 reflectionsΔρmin = 0.33 e Å3
189 parameters
Special details top

Experimental. CrysAlisPro, Oxford Diffraction Ltd., Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
Br10.64263 (9)0.24500 (13)0.04609 (4)0.0951 (4)
N10.4336 (5)0.4954 (6)0.1405 (2)0.0504 (15)
H10.435 (6)0.6246 (17)0.138 (2)0.061*
N30.3225 (5)0.2096 (6)0.1096 (2)0.0468 (14)
H30.253 (3)0.163 (7)0.087 (2)0.056*
O20.2482 (5)0.5076 (6)0.0762 (2)0.0786 (16)
O60.6264 (5)0.4897 (5)0.1981 (2)0.0752 (16)
O40.3920 (4)0.0903 (5)0.13692 (18)0.0579 (13)
C20.3306 (7)0.4133 (8)0.1065 (3)0.0519 (18)
C40.4088 (6)0.0884 (8)0.1410 (3)0.0450 (16)
C50.5229 (6)0.1748 (6)0.1812 (3)0.0386 (15)
C60.5334 (7)0.4010 (8)0.1731 (3)0.0505 (18)
C70.6478 (6)0.0760 (8)0.1667 (3)0.0501 (17)
H7A0.71910.16160.18170.060*
H7B0.65880.04630.18990.060*
C80.6567 (6)0.0305 (9)0.1013 (3)0.0606 (19)
C90.6782 (7)0.1521 (11)0.0779 (3)0.084 (2)
H9A0.68860.26090.10400.101*
H9B0.68230.16750.03600.101*
C100.5050 (7)0.1407 (8)0.2512 (3)0.0605 (19)
H100.58150.19590.27560.073*
C120.4966 (9)0.0656 (10)0.2707 (4)0.097 (3)
H12A0.55440.14610.24990.117*
H12B0.40990.11400.25930.117*
C130.5331 (10)0.0833 (13)0.3418 (3)0.129 (4)
H13D0.60670.00200.35460.193*
H13E0.55300.21840.35250.193*
H13F0.46220.04040.36220.193*
C140.3888 (8)0.2595 (10)0.2694 (3)0.103 (3)
H14A0.40320.39820.26400.154*
H14B0.37930.23380.31170.154*
H14C0.31200.22010.24360.154*
O1S0.1014 (4)0.0764 (5)0.04030 (19)0.0650 (14)
C1S0.0085 (7)0.2010 (7)0.0056 (3)0.072 (2)
H1S10.04910.32430.00360.086*
H1S20.05950.23130.03030.086*
C2S0.0465 (7)0.1081 (8)0.0515 (3)0.066 (2)
H2S10.02000.08990.07810.080*
H2S20.11190.19380.07270.080*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.1010 (8)0.1162 (6)0.0699 (6)0.0078 (6)0.0173 (5)0.0284 (5)
N10.050 (4)0.025 (2)0.070 (3)0.006 (3)0.019 (3)0.003 (3)
N30.048 (4)0.025 (2)0.062 (3)0.006 (2)0.014 (3)0.002 (2)
O20.068 (4)0.046 (2)0.112 (4)0.003 (2)0.028 (3)0.021 (2)
O60.072 (4)0.051 (2)0.092 (4)0.017 (2)0.032 (3)0.008 (2)
O40.063 (3)0.027 (2)0.078 (3)0.0022 (19)0.011 (2)0.0016 (19)
C20.056 (5)0.037 (3)0.061 (4)0.004 (3)0.000 (4)0.009 (3)
C40.057 (5)0.036 (3)0.042 (4)0.002 (3)0.006 (3)0.006 (3)
C50.043 (4)0.027 (3)0.044 (4)0.001 (3)0.003 (3)0.005 (2)
C60.059 (5)0.042 (3)0.046 (4)0.009 (4)0.011 (4)0.002 (3)
C70.044 (5)0.047 (3)0.059 (4)0.000 (3)0.003 (3)0.001 (3)
C80.049 (5)0.066 (4)0.068 (5)0.003 (4)0.009 (4)0.002 (4)
C90.091 (7)0.098 (5)0.068 (5)0.003 (5)0.031 (5)0.005 (4)
C100.082 (6)0.050 (3)0.052 (4)0.020 (4)0.017 (4)0.006 (3)
C120.107 (8)0.084 (5)0.103 (7)0.001 (5)0.023 (6)0.008 (5)
C130.144 (9)0.186 (8)0.060 (6)0.060 (8)0.029 (6)0.072 (6)
C140.132 (8)0.114 (6)0.067 (5)0.072 (6)0.032 (5)0.019 (5)
O1S0.058 (3)0.046 (2)0.080 (3)0.003 (2)0.031 (3)0.001 (2)
C1S0.071 (5)0.041 (3)0.097 (6)0.006 (3)0.016 (4)0.002 (4)
C2S0.073 (6)0.056 (4)0.063 (5)0.004 (4)0.014 (4)0.012 (3)
Geometric parameters (Å, º) top
Br1—C81.881 (6)C10—C121.466 (8)
N1—C61.351 (7)C10—C141.553 (9)
N1—C21.351 (7)C10—H100.9800
N1—H10.876 (10)C12—C131.558 (9)
N3—C41.344 (6)C12—H12A0.9700
N3—C21.384 (7)C12—H12B0.9700
N3—H30.89 (4)C13—H13D0.9600
O2—C21.203 (6)C13—H13E0.9600
O6—C61.215 (6)C13—H13F0.9600
O4—C41.224 (5)C14—H14A0.9600
C4—C51.510 (7)C14—H14B0.9600
C5—C71.540 (8)C14—H14C0.9600
C5—C61.547 (7)O1S—C2S1.410 (7)
C5—C101.583 (8)O1S—C1S1.431 (7)
C7—C81.479 (8)C1S—C2Si1.452 (8)
C7—H7A0.9700C1S—H1S10.9700
C7—H7B0.9700C1S—H1S20.9700
C8—C91.366 (8)C2S—C1Si1.452 (8)
C9—H9A0.9300C2S—H2S10.9700
C9—H9B0.9300C2S—H2S20.9700
C6—N1—C2127.5 (5)C14—C10—C5111.4 (5)
C6—N1—H1119 (4)C12—C10—H10106.3
C2—N1—H1113 (4)C14—C10—H10106.3
C4—N3—C2126.3 (5)C5—C10—H10106.3
C4—N3—H3121 (3)C10—C12—C13110.3 (6)
C2—N3—H3112 (3)C10—C12—H12A109.6
O2—C2—N1123.6 (5)C13—C12—H12A109.6
O2—C2—N3120.8 (6)C10—C12—H12B109.6
N1—C2—N3115.6 (5)C13—C12—H12B109.6
O4—C4—N3118.9 (5)H12A—C12—H12B108.1
O4—C4—C5121.4 (5)C12—C13—H13D109.5
N3—C4—C5119.6 (4)C12—C13—H13E109.5
C4—C5—C7110.2 (4)H13D—C13—H13E109.5
C4—C5—C6112.3 (5)C12—C13—H13F109.5
C7—C5—C6109.4 (5)H13D—C13—H13F109.5
C4—C5—C10108.8 (5)H13E—C13—H13F109.5
C7—C5—C10110.2 (5)C10—C14—H14A109.5
C6—C5—C10105.9 (4)C10—C14—H14B109.5
O6—C6—N1121.9 (5)H14A—C14—H14B109.5
O6—C6—C5120.2 (5)C10—C14—H14C109.5
N1—C6—C5117.8 (5)H14A—C14—H14C109.5
C8—C7—C5116.7 (5)H14B—C14—H14C109.5
C8—C7—H7A108.1C2S—O1S—C1S110.4 (4)
C5—C7—H7A108.1O1S—C1S—C2Si111.7 (5)
C8—C7—H7B108.1O1S—C1S—H1S1109.3
C5—C7—H7B108.1C2Si—C1S—H1S1109.3
H7A—C7—H7B107.3O1S—C1S—H1S2109.3
C9—C8—C7125.7 (6)C2Si—C1S—H1S2109.3
C9—C8—Br1117.5 (6)H1S1—C1S—H1S2107.9
C7—C8—Br1116.8 (4)O1S—C2S—C1Si111.1 (5)
C8—C9—H9A120.0O1S—C2S—H2S1109.4
C8—C9—H9B120.0C1Si—C2S—H2S1109.4
H9A—C9—H9B120.0O1S—C2S—H2S2109.4
C12—C10—C14110.0 (7)C1Si—C2S—H2S2109.4
C12—C10—C5116.0 (5)H2S1—C2S—H2S2108.0
Symmetry code: (i) x, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O4ii0.88 (1)1.98 (2)2.837 (5)166 (6)
N3—H3···O1S0.89 (4)1.87 (4)2.757 (6)177 (5)
Symmetry code: (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC11H15BrN2O3·0.5C4H8O2
Mr347.21
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)10.494 (2), 6.7679 (8), 21.864 (3)
β (°) 97.294 (15)
V3)1540.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)2.68
Crystal size (mm)0.25 × 0.08 × 0.07
Data collection
DiffractometerOxford Diffraction Xcalibur Ruby Gemini ultra
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2007)
Tmin, Tmax0.990, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
9189, 2714, 1171
Rint0.100
(sin θ/λ)max1)0.596
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.145, 0.95
No. of reflections2714
No. of parameters189
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.56, 0.33

Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008) and Mercury (Bruno et al., 2002), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O4i0.876 (10)1.980 (18)2.837 (5)166 (6)
N3—H3···O1S0.89 (4)1.87 (4)2.757 (6)177 (5)
Symmetry code: (i) x, y+1, z.
 

Acknowledgements

TG acknowledges financial support from the Lise Meitner Program of the Austrian Science Fund (FWF, project LM 1135-N17).

References

First citationAl-Saqqar, S., Falvello, L. R. & Soler, T. (2004). J. Chem. Crystallogr. 34, 61–65.  Web of Science CSD CrossRef CAS Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
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