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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2990–o2991.
Published online 2010 October 31. doi:  10.1107/S160053681004300X
PMCID: PMC3009374

6-Butyl-5-(4-methyl­phen­oxy)-3-phenyl-3H-1,2,3-triazolo[4,5-d]pyrimidin-7(6H)-one

Abstract

In the title compound, C21H21N5O2, the triazolopyrimidine ring system is essentially planar [maximum displacement = 0.021 (4) Å] and forms dihedral angles of 41.17 (9) and 67.99 (8)° with the phenyl and benzene rings, respectively. The n-butyl side chains is disordered over two positions with an ccupancy ratio of 0.77:0.23. An intra­molecular C—H(...)O hydrogen-bonding inter­action stabilizes the mol­ecular conformation. In the crystal, mol­ecules are linked by inter­molecular C—H(...)O and C—H(...)N hydrogen bonds into a three-dimensional network. In addition, π–π stacking inter­actions involving the triazole and pyrimidine rings of adjacent mol­ecules are observed, with centroid–centroid distances of 3.545 (1) Å.

Related literature

For the synthesis and biological activity of 8-aza­guanine derivatives, see: Roblin et al. (1945 [triangle]); Ding et al. (2004 [triangle]); Mitchell et al. (1950 [triangle]); Levine et al. (1963 [triangle]); Montgomery et al. (1962 [triangle]); Yamamoto et al. (1967 [triangle]); Bariana (1971 [triangle]); Holland et al. (1975 [triangle]); Zeng et al. (2010 [triangle]). For related structures, see: Ferguson et al. (1998 [triangle]); Li et al. (2004 [triangle]); Zhao, Xie et al. (2005 [triangle]); Zhao, Hu et al. (2005 [triangle]); Zhao, Wang & Ding (2005 [triangle]); Chen & Shi (2006 [triangle]); Maldonado et al. (2006 [triangle]); Xiao et al. (2007 [triangle]); Wang et al. (2006 [triangle], 2008 [triangle]); Zeng et al. (2006 [triangle], 2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2990-scheme1.jpg

Experimental

Crystal data

  • C21H21N5O2
  • M r = 375.43
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2990-efi1.jpg
  • a = 11.0954 (10) Å
  • b = 16.4478 (15) Å
  • c = 11.3484 (11) Å
  • β = 107.643 (1)°
  • V = 1973.6 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 298 K
  • 0.20 × 0.20 × 0.20 mm

Data collection

  • Bruker SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.983, T max = 0.985
  • 20458 measured reflections
  • 3876 independent reflections
  • 2663 reflections with I > 2σ(I)
  • R int = 0.055

Refinement

  • R[F 2 > 2σ(F 2)] = 0.054
  • wR(F 2) = 0.182
  • S = 1.08
  • 3876 reflections
  • 293 parameters
  • 11 restraints
  • H-atom parameters constrained
  • Δρmax = 0.56 e Å−3
  • Δρmin = −0.24 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681004300X/rz2502sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681004300X/rz2502Isup2.hkl

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

Acknowledgments

The authors gratefully acknowledge financial support of this work by the National Basic Research Program of China (2003CB114400), the National Natural Science Foundation of China (20372023, 20102001), the Educational Commission of Hubei Province of China (grant No. B200624004, B20092412), Shiyan Municipal Science and Technology Bureau (grant No. 20061835) and Yunyang Medical College (grant Nos. 2007QDJ15, 2007ZQB19, 2007ZQB20).

supplementary crystallographic information

Comment

The derivatives of heterocycles containing 8-azaguanine system, which are well known bioisosteres of guanine, are of great importance because of their remarkable biological properties. Some of these activities include antimicrobial or antifungal activities (Roblin et al., 1945; Ding et al., 2004; Zeng et al., 2010), encephaloma cell inhibitor activity (Mitchell et al., 1950; Levine et al., 1963), antileukemic activity (Montgomery et al., 1962), hypersusceptibility inhibitor activity and acesodyne activity (Yamamoto et al., 1967; Bariana, 1971; Holland et al., 1975). In recent years, Ding's group has been engaged in the preparation of derivatives of 8-azaguanine via aza-Wittig reaction of beta-ethoxycarbonyl iminophosphoranes with aromatic isocyanates (Zhao, Xie et al., 2005). As a continuation of our research for new biologically active heterocycles, the title compound was obtained from beta-ethoxycarbonyl iminophosphorane with alphalic isocyanate, and structurally characterized in this context.

In the title compound (Fig. 1), bond lengths and angles within the triazolopyrimidinone moiety are in good agreement with those observed for closely related structures (Zhao, Hu et al., 2005; Zhao, Wang & Ding, 2005). As reported for related compounds (Ferguson et al., 1998; Li et al., 2004; Maldonado et al., 2006; Zeng et al., 2006, 2009; Wang et al., 2006, 2008; Xiao et al., 2007; Chen & Shi, 2006), the triazolopyrimidine ring system is essentially planar, with a maximum displacement of 0.021 (4) Å for atom C8, and forms dihedral angles of 41.17 (9) and 67.99 (8)° with the C1–C6 and C15–C20 rings, respectively. There exists an intramolecular C—H···O hydrogen bonding interaction stabilizing the molecular conformation. In the crystal packing, molecules are linked by intermolecular C—H···O and C—H···N hydrogen bonds (Table 1). In addition, π–π stacking interactions involving the triazole and pyrimidine rings of adjacent molecules are observed, with cenroid-to-centroid distances of 3.545 (1) Å.

Experimental

To the solution of carbodiimide in CH2Cl2/CH3CN (1:4 v/v, 15 ml) prepared according to the literature method (Zeng et al., 2006), was added 4-methylphenol (3 mmol) and excess K2CO3, and the reaction mixture was stirred for 12 h. The solvent was removed under reduced pressure and the residue was recrystallized from EtOH to give the title compound (yield 93%; m.p. 406 K). Elemental analysis: calculated for C21H21N5O2: C, 67.18; H, 5.64; N, 18.65%. Found: C, 66.62; H, 5.98; N, 18.13%. Crystals suitable for single crystal X-ray diffraction analysis were obtained by slow evaporation of a hexane/dichloromethane (1:3 v/v) solution at room temperature.

Refinement

H atoms were placed at calculated positions and treated as riding atoms, with C—H = 0.93–0.97 Å, and Uiso(H) = 1.2Ueq(C) for CH or 1.5Ueq(C) for CH3. The n-butyl side chain is disordered over two positions with occupancy factors of 0.77:0.23. During the refinement, the adjacent and interval C—C distances involving the disordered carbon atoms were restrained to be 1.54 (1)Å and 2.45 (2) Å, respectively, by using the command DFIX.

Figures

Fig. 1.
The molecular structure of the title compound showing the atom-labeling scheme. Displacement ellipsoids are drawn at 50% probability level. H-atoms are represented by circles of arbitrary size. Only the major component of the disorder is shown.

Crystal data

C21H21N5O2F(000) = 792
Mr = 375.43Dx = 1.263 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6350 reflections
a = 11.0954 (10) Åθ = 2.3–25.8°
b = 16.4478 (15) ŵ = 0.09 mm1
c = 11.3484 (11) ÅT = 298 K
β = 107.643 (1)°Block, colourless
V = 1973.6 (3) Å30.20 × 0.20 × 0.20 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer3876 independent reflections
Radiation source: fine-focus sealed tube2663 reflections with I > 2σ(I)
graphiteRint = 0.055
[var phi] and ω scansθmax = 26.0°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −13→13
Tmin = 0.983, Tmax = 0.985k = −20→20
20458 measured reflectionsl = −13→13

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.182H-atom parameters constrained
S = 1.08w = 1/[σ2(Fo2) + (0.1122P)2 + 0.0419P] where P = (Fo2 + 2Fc2)/3
3876 reflections(Δ/σ)max < 0.001
293 parametersΔρmax = 0.56 e Å3
11 restraintsΔρmin = −0.24 e Å3

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.
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)

xyzUiso*/UeqOcc. (<1)
C10.42419 (17)0.24051 (13)0.45138 (17)0.0654 (5)
C20.5223 (2)0.26001 (14)0.5541 (2)0.0797 (6)
H20.58100.22080.59360.096*
C30.5326 (2)0.33854 (15)0.5978 (2)0.0904 (7)
H30.59800.35230.66820.108*
C40.4468 (3)0.39682 (15)0.5381 (3)0.0909 (7)
H40.45430.44990.56770.109*
C50.3502 (2)0.37608 (16)0.4348 (3)0.0923 (7)
H50.29220.41540.39420.111*
C60.3380 (2)0.29824 (14)0.3907 (2)0.0764 (6)
H60.27230.28450.32050.092*
C70.49373 (17)0.10245 (12)0.39629 (16)0.0616 (5)
C80.42311 (18)0.03487 (12)0.34748 (17)0.0659 (5)
C90.4821 (2)−0.03604 (13)0.31905 (17)0.0681 (5)
C100.67331 (18)0.04538 (13)0.39924 (17)0.0670 (5)
C110.6857 (6)−0.0970 (5)0.3246 (5)0.0795 (18)0.77
H11A0.6320−0.14480.31090.095*0.77
H11B0.7589−0.10730.39560.095*0.77
C120.7294 (5)−0.0808 (4)0.2082 (5)0.138 (2)0.77
H12A0.7829−0.03280.22380.166*0.77
H12B0.7810−0.12630.19800.166*0.77
C130.6379 (6)−0.0699 (3)0.1027 (5)0.149 (2)0.77
H13A0.6006−0.01680.10500.179*0.77
H13B0.5726−0.11010.09790.179*0.77
C140.6776 (10)−0.0757 (5)−0.0175 (6)0.142 (4)0.77
H14A0.7472−0.0395−0.01140.213*0.77
H14B0.6074−0.0606−0.08740.213*0.77
H14C0.7026−0.1304−0.02790.213*0.77
C11'0.704 (2)−0.0825 (18)0.3141 (15)0.104 (10)0.23
H11C0.7847−0.05550.32910.125*0.23
H11D0.7168−0.12960.36790.125*0.23
C12'0.6617 (12)−0.1107 (8)0.1849 (10)0.081 (3)0.23
H12C0.6172−0.16100.18800.097*0.23
H12D0.5967−0.07200.14310.097*0.23
C13'0.7276 (11)−0.1267 (7)0.0973 (8)0.104 (4)0.23
H13C0.8104−0.10240.13290.125*0.23
H13D0.7414−0.18500.10150.125*0.23
C14'0.695 (2)−0.1081 (15)−0.0281 (18)0.101 (6)0.23
H14D0.6086−0.1234−0.06760.152*0.23
H14E0.7492−0.1374−0.06500.152*0.23
H14F0.7046−0.0508−0.03810.152*0.23
C150.87510 (18)0.10857 (13)0.4721 (2)0.0717 (6)
C160.9372 (2)0.14531 (16)0.4005 (2)0.0856 (7)
H160.92380.12890.31910.103*
C171.0212 (2)0.20782 (16)0.4509 (2)0.0895 (7)
H171.06320.23380.40200.107*
C181.04316 (19)0.23192 (14)0.5710 (2)0.0809 (6)
C190.9782 (2)0.19289 (17)0.6399 (2)0.0904 (7)
H190.99130.20880.72150.108*
C200.8938 (2)0.13042 (16)0.5914 (2)0.0865 (7)
H200.85110.10420.63960.104*
C211.1367 (3)0.29832 (18)0.6258 (3)0.1124 (9)
H21A1.21730.28470.61630.169*
H21B1.14490.30400.71210.169*
H21C1.10740.34860.58400.169*
N10.40888 (13)0.15838 (10)0.40749 (14)0.0651 (4)
N20.28911 (15)0.12506 (12)0.36653 (17)0.0760 (5)
N30.29856 (15)0.05057 (12)0.33090 (16)0.0763 (5)
N40.61476 (15)−0.02544 (10)0.34970 (14)0.0686 (5)
N50.62063 (14)0.11114 (10)0.42446 (15)0.0660 (4)
O10.43198 (15)−0.09929 (10)0.27448 (15)0.0877 (5)
O20.79833 (13)0.04150 (9)0.41997 (15)0.0840 (5)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0492 (10)0.0861 (14)0.0599 (11)0.0031 (9)0.0152 (8)0.0080 (10)
C20.0634 (12)0.0853 (15)0.0760 (14)0.0001 (11)−0.0002 (10)0.0097 (11)
C30.0771 (15)0.0954 (17)0.0843 (15)−0.0114 (13)0.0029 (12)0.0014 (13)
C40.0866 (17)0.0855 (15)0.1014 (19)−0.0009 (13)0.0299 (14)0.0018 (13)
C50.0803 (16)0.0996 (18)0.0938 (18)0.0185 (13)0.0215 (13)0.0128 (14)
C60.0601 (12)0.0930 (16)0.0707 (13)0.0125 (10)0.0115 (10)0.0046 (11)
C70.0500 (10)0.0810 (12)0.0489 (10)−0.0003 (9)0.0079 (7)0.0085 (8)
C80.0558 (11)0.0851 (13)0.0507 (10)−0.0027 (9)0.0068 (8)0.0085 (9)
C90.0658 (12)0.0824 (14)0.0495 (10)−0.0053 (10)0.0074 (8)0.0065 (9)
C100.0532 (11)0.0879 (14)0.0570 (11)0.0019 (10)0.0121 (8)0.0019 (10)
C110.075 (2)0.086 (3)0.076 (3)0.011 (3)0.020 (2)−0.004 (2)
C120.111 (4)0.156 (5)0.147 (5)−0.007 (3)0.038 (4)−0.070 (4)
C130.205 (6)0.147 (4)0.114 (3)0.064 (4)0.077 (4)0.047 (3)
C140.200 (8)0.147 (7)0.095 (4)−0.014 (5)0.069 (4)0.014 (4)
C11'0.129 (17)0.097 (15)0.105 (15)−0.015 (10)0.064 (12)−0.019 (10)
C12'0.077 (7)0.097 (8)0.069 (7)−0.011 (6)0.022 (6)−0.018 (6)
C13'0.115 (10)0.090 (7)0.097 (9)0.002 (7)0.015 (7)−0.010 (6)
C14'0.090 (10)0.108 (15)0.106 (12)−0.014 (9)0.030 (8)0.001 (9)
C150.0446 (10)0.0929 (14)0.0758 (13)0.0081 (10)0.0154 (9)−0.0068 (11)
C160.0669 (13)0.1198 (18)0.0734 (14)0.0020 (13)0.0264 (11)−0.0123 (13)
C170.0689 (14)0.1146 (18)0.0916 (17)−0.0009 (13)0.0341 (12)−0.0005 (14)
C180.0544 (11)0.0949 (15)0.0930 (16)0.0076 (11)0.0217 (11)−0.0096 (12)
C190.0702 (14)0.127 (2)0.0742 (14)−0.0021 (13)0.0221 (11)−0.0188 (13)
C200.0644 (13)0.1234 (19)0.0741 (15)−0.0102 (13)0.0247 (11)−0.0068 (13)
C210.0855 (18)0.119 (2)0.133 (2)−0.0136 (16)0.0334 (17)−0.0260 (18)
N10.0459 (8)0.0832 (11)0.0604 (9)0.0038 (8)0.0072 (7)0.0055 (8)
N20.0471 (9)0.0998 (13)0.0749 (11)−0.0033 (8)0.0091 (8)0.0027 (9)
N30.0534 (10)0.0983 (13)0.0695 (10)−0.0053 (9)0.0072 (8)0.0046 (9)
N40.0641 (10)0.0817 (11)0.0557 (9)0.0031 (8)0.0118 (7)0.0001 (8)
N50.0480 (9)0.0836 (11)0.0630 (9)0.0007 (8)0.0116 (7)0.0018 (8)
O10.0859 (11)0.0879 (11)0.0802 (10)−0.0134 (8)0.0117 (8)−0.0049 (8)
O20.0526 (8)0.1000 (11)0.0981 (11)0.0020 (7)0.0209 (7)−0.0187 (8)

Geometric parameters (Å, °)

C1—C21.370 (3)C14—H14B0.9600
C1—C61.375 (3)C14—H14C0.9600
C1—N11.432 (3)C11'—C12'1.473 (10)
C2—C31.376 (3)C11'—N41.502 (10)
C2—H20.9300C11'—H11C0.9700
C3—C41.376 (3)C11'—H11D0.9700
C3—H30.9300C12'—C13'1.426 (9)
C4—C51.371 (4)C12'—H12C0.9700
C4—H40.9300C12'—H12D0.9700
C5—C61.366 (3)C13'—C14'1.39 (2)
C5—H50.9300C13'—H13C0.9700
C6—H60.9300C13'—H13D0.9700
C7—N11.349 (2)C14'—H14D0.9600
C7—N51.354 (2)C14'—H14E0.9600
C7—C81.376 (3)C14'—H14F0.9600
C8—N31.362 (3)C15—C201.355 (3)
C8—C91.422 (3)C15—C161.356 (3)
C9—O11.215 (2)C15—O21.410 (3)
C9—N41.416 (3)C16—C171.389 (3)
C10—N51.302 (3)C16—H160.9300
C10—O21.336 (2)C17—C181.369 (3)
C10—N41.369 (3)C17—H170.9300
C11—N41.491 (4)C18—C191.373 (3)
C11—C121.562 (8)C18—C211.505 (3)
C11—H11A0.9700C19—C201.387 (3)
C11—H11B0.9700C19—H190.9300
C12—C131.326 (6)C20—H200.9300
C12—H12A0.9700C21—H21A0.9600
C12—H12B0.9700C21—H21B0.9600
C13—C141.559 (7)C21—H21C0.9600
C13—H13A0.9700N1—N21.381 (2)
C13—H13B0.9700N2—N31.304 (3)
C14—H14A0.9600
C2—C1—C6121.1 (2)C13'—C12'—H12C104.1
C2—C1—N1119.77 (18)C11'—C12'—H12C104.1
C6—C1—N1119.07 (18)C13'—C12'—H12D104.1
C1—C2—C3118.9 (2)C11'—C12'—H12D104.1
C1—C2—H2120.5H12C—C12'—H12D105.5
C3—C2—H2120.5C14'—C13'—C12'130.0 (14)
C4—C3—C2120.5 (2)C14'—C13'—H13C104.8
C4—C3—H3119.8C12'—C13'—H13C104.8
C2—C3—H3119.8C14'—C13'—H13D104.8
C5—C4—C3119.5 (2)C12'—C13'—H13D104.8
C5—C4—H4120.2H13C—C13'—H13D105.8
C3—C4—H4120.2C13'—C14'—H14D109.5
C6—C5—C4120.8 (2)C13'—C14'—H14E109.5
C6—C5—H5119.6H14D—C14'—H14E109.5
C4—C5—H5119.6C13'—C14'—H14F109.5
C5—C6—C1119.1 (2)H14D—C14'—H14F109.5
C5—C6—H6120.4H14E—C14'—H14F109.5
C1—C6—H6120.4C20—C15—C16121.9 (2)
N1—C7—N5127.68 (18)C20—C15—O2121.1 (2)
N1—C7—C8105.08 (17)C16—C15—O2116.70 (19)
N5—C7—C8127.23 (19)C15—C16—C17118.9 (2)
N3—C8—C7109.43 (18)C15—C16—H16120.6
N3—C8—C9129.96 (19)C17—C16—H16120.6
C7—C8—C9120.58 (19)C18—C17—C16121.3 (2)
O1—C9—N4121.2 (2)C18—C17—H17119.4
O1—C9—C8127.7 (2)C16—C17—H17119.4
N4—C9—C8111.04 (18)C17—C18—C19117.8 (2)
N5—C10—O2120.81 (18)C17—C18—C21120.9 (2)
N5—C10—N4127.48 (18)C19—C18—C21121.3 (2)
O2—C10—N4111.70 (18)C18—C19—C20121.9 (2)
N4—C11—C12110.1 (5)C18—C19—H19119.0
N4—C11—H11A109.6C20—C19—H19119.0
C12—C11—H11A109.6C15—C20—C19118.2 (2)
N4—C11—H11B109.6C15—C20—H20120.9
C12—C11—H11B109.6C19—C20—H20120.9
H11A—C11—H11B108.2C18—C21—H21A109.5
C13—C12—C11115.9 (5)C18—C21—H21B109.5
C13—C12—H12A108.3H21A—C21—H21B109.5
C11—C12—H12A108.3C18—C21—H21C109.5
C13—C12—H12B108.3H21A—C21—H21C109.5
C11—C12—H12B108.3H21B—C21—H21C109.5
H12A—C12—H12B107.4C7—N1—N2108.99 (17)
C12—C13—C14116.1 (6)C7—N1—C1131.55 (16)
C12—C13—H13A108.3N2—N1—C1119.47 (15)
C14—C13—H13A108.3N3—N2—N1108.51 (16)
C12—C13—H13B108.3N2—N3—C8107.99 (16)
C14—C13—H13B108.3C10—N4—C9122.28 (17)
H13A—C13—H13B107.4C10—N4—C11122.6 (4)
C12'—C11'—N4115.4 (11)C9—N4—C11115.2 (4)
C12'—C11'—H11C108.4C10—N4—C11'111.9 (13)
N4—C11'—H11C108.4C9—N4—C11'125.1 (12)
C12'—C11'—H11D108.4C11—N4—C11'13.6 (18)
N4—C11'—H11D108.4C10—N5—C7111.38 (17)
H11C—C11'—H11D107.5C10—O2—C15119.97 (16)
C13'—C12'—C11'132.7 (14)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C12—H12A···O20.972.503.048 (5)116
C2—H2···O1i0.932.533.230 (3)133
C3—H3···N2ii0.932.613.535 (2)174

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2502).

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