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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 5| May 2009| Page o1182

6-Bromo-1-methyl-1H-2,1-benzo­thia­zin-4(3H)-one 2,2-dioxide

aGovernment College University, Department of Chemistry, Lahore, Pakistan, and bUniversity of Sargodha, Department of Physics, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 6 March 2009; accepted 28 April 2009; online 30 April 2009)

In the crystal structure of the title compound, C9H8BrNO3S, the thia­zine ring is in the twisted form. In the crystal, pairs of inter­molecular C—H⋯O hydrogen bonds form inversion dimers with an R22(8) ring motif. Weak inter­molecular C—H⋯Br and C—H⋯π inter­actions are also present.

Related literature

For the structures of benzothia­zine derivatives, see: Arshad et al. (2008[Arshad, M. N., Tahir, M. N., Khan, I. U., Shafiq, M. & Siddiqui, W. A. (2008). Acta Cryst. E64, o2045.]); Shafiq et al. (2008a[Shafiq, M., Khan, I. U., Tahir, M. N. & Siddiqui, W. A. (2008a). Acta Cryst. E64, o558.],b[Shafiq, M., Tahir, M. N., Khan, I. U., Ahmad, S. & Siddiqui, W. A. (2008b). Acta Cryst. E64, o1270.]); Tahir et al. (2008[Tahir, M. N., Shafiq, M., Khan, I. U., Siddiqui, W. A. & Arshad, M. N. (2008). Acta Cryst. E64, o557.]). For the related structure, 6-bromo-1-methyl-1H-benzo[c][1,2]thia­zin-4(3H)-one 2,2-dioxide, see: Shafiq et al. (2009[Shafiq, M., Tahir, M. N., Khan, I. U., Arshad, M. N. & Safdar, M. (2009). Acta Cryst. E65, o393.]). 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.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For the synthesis, see: Lombardino (1972[Lombardino, J. G. (1972). J. Heterocycl. Chem. 9, 315-317.]).

[Scheme 1]

Experimental

Crystal data
  • C9H8BrNO3S

  • Mr = 290.13

  • Monoclinic, P 21 /n

  • a = 5.4577 (3) Å

  • b = 12.6400 (8) Å

  • c = 15.1258 (10) Å

  • β = 96.204 (2)°

  • V = 1037.35 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.15 mm−1

  • T = 296 K

  • 0.20 × 0.17 × 0.15 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.439, Tmax = 0.540

  • 11077 measured reflections

  • 2234 independent reflections

  • 1709 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.030

  • wR(F2) = 0.072

  • S = 1.04

  • 2234 reflections

  • 137 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.35 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O3i 0.93 2.54 3.308 (4) 140
C8—H8A⋯O2ii 0.97 2.54 3.470 (3) 162
C9—H9B⋯O3 0.96 2.41 2.824 (3) 106
C5—H5⋯Br1iii 0.93 2.94 3.871 (3) 175
C9—H9A⋯Br1iv 0.96 3.01 3.871 (2) 150
C9—H9CCg1v 0.96 2.83 3.449 (3) 123
Symmetry codes: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x+1, -y, -z+1; (iii) -x, -y+1, -z+1; (iv) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) x+1, y, z. Cg1 is the centroid of the C1–C6 ring.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. 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: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

We have reported crystal structures of the synthesized derivatives of the benzothiazine molecule (Shafiq et al., 2008a; Shafiq et al., 2008b; Tahir et al., 2008; Arshad et al., 2008). Here we report the title compound (I), (Fig. 1), that belongs to this series of the structures.

(I) is closely related to the crystal structure of 6-bromo-1-methyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide, (II), (Shafiq et al., 2009). (I) and (II) differ by the presence of the methyl and ethyl groups at the N-atom, respectively. The bromo-substituted benzene ring A (C1—C6) is planar with Br deviated by 0.064 (4) Å from the mean plane. The thiazine ring B (S1/N1/C1/C6—C8) is in the twisted form, with the maximum puckering amplitude QT = 0.577 (2) Å (Cremer & Pople, 1975). The title molecules form dimers interconnected by a pair of the intermolecular H-bonds C8–H8A···O2i [symmetry code: i = -x + 1, -y, -z + 1] with the R22(8) ring motif (Bernstein et al., 1995), (Tab. 1, Fig. 2). The dimers are linked to each other forming helices through the other intermolecular H-bonding C3–H3···O3ii [symmetry code: ii = -x + 3/2, y + 1/2, -z + 1/2]. The molecules are also stabilized due to C—H···π-electron interaction with the benzene group and intermolecular C—H···Br interactions (Tab. 1).

Related literature top

For the structures of benzothiazine derivatives, see: Arshad et al. (2008); Shafiq et al. (2008a,b); Tahir et al. (2008). For the related structure, 6-bromo-1-methyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide, see: Shafiq et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering parameters, see: Cremer & Pople (1975). For the synthesis, see: Lombardino (1972). Cg1 is the centroid of the C1–C6 ring.

Experimental top

The title compound was prepared in a three step scheme following the reported procedure (Lombardino, 1972). In the first step, methyl-2-amino-5-bromobenzoate (92 mg, 4 mmol) was put in dichloromethane (10 ml) and this mixture was introduced into a round bottom flask. A solution of methanesulfonyl chloride (550 mg, 4.8 mmol) in dichloromethane (10 ml) was slowly added (10-15 minutes) to this mixture. The mixture was stirred at 60–70 °C for 2–3 days keeping pH of the mixture alkaline by triethylamine. After the completion of the reaction, the solvent was evaporated under reduced pressure to get methyl-5-bromo-2-[(methylsulfonyl)amino] benzoate.

In the second step, methyl-5-bromo-2-[(methylsulfonyl)amino] benzoate (1.02 g, 3.3 mmol) was introduced into 5 ml of N,N-dimethylformamide (DMF). The mixture was added to a suspension of NaH (158.38 mg, 6.6 mmol) in DMF (10 ml). The mixture was stirred at room temperature for 14–16 h. After that, methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate was obtained.

In the third step methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate was cyclized. Therefore methyl-5-bromo-2-[methyl(methylsulfonyl)amino]benzoate (418.83 mg, 1.3 mmol) was introduced in DMF (5 ml) and added to the suspension of NaH (59.99 mg, 2.5 mmol) in DMF (10 ml). The mixture was stirred at room temperature for 3–4 h. Then the reaction mixture was poured into ice and clear solution was obtained. The pH of this solution was adjusted between 5–6. The precipitated crude product was recrystallized from ethanol. Yellow needle-shaped crystals of the title compound of suitable size for structure analysis were grown in this way.

Refinement top

Though all the hydrogens were discernible in the difference electron density map, the H-atoms were situated into idealized positions, with C-H = 0.93, 0.96 and 0.97 Å for aryl, methyl and methylene H, resepctively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl and 1.2 for other carrier atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The title compound, with the atom-numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. The H-atoms are shown by small circles of arbitrary radius. The dotted lines show the intramolecular H-bonds.
[Figure 2] Fig. 2. A section of the title structure showing the dimers bind by the hydrogen bonds.
6-Bromo-1-methyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide top
Crystal data top
C9H8BrNO3SF(000) = 576
Mr = 290.13Dx = 1.858 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2234 reflections
a = 5.4577 (3) Åθ = 2.1–27.0°
b = 12.6400 (8) ŵ = 4.15 mm1
c = 15.1258 (10) ÅT = 296 K
β = 96.204 (2)°Prism, yellow
V = 1037.35 (11) Å30.20 × 0.17 × 0.15 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2234 independent reflections
Radiation source: fine-focus sealed tube1709 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
Detector resolution: 7.40 pixels mm-1θmax = 27.0°, θmin = 2.1°
ω scansh = 66
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1616
Tmin = 0.439, Tmax = 0.540l = 1819
11077 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)] = 0.030Hydrogen site location: difference Fourier map
wR(F2) = 0.072H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0309P)2 + 0.4349P]
where P = (Fo2 + 2Fc2)/3
2234 reflections(Δ/σ)max = 0.001
137 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.35 e Å3
31 constraints
Crystal data top
C9H8BrNO3SV = 1037.35 (11) Å3
Mr = 290.13Z = 4
Monoclinic, P21/nMo Kα radiation
a = 5.4577 (3) ŵ = 4.15 mm1
b = 12.6400 (8) ÅT = 296 K
c = 15.1258 (10) Å0.20 × 0.17 × 0.15 mm
β = 96.204 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2234 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1709 reflections with I > 2σ(I)
Tmin = 0.439, Tmax = 0.540Rint = 0.032
11077 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0300 restraints
wR(F2) = 0.072H-atom parameters constrained
S = 1.04Δρmax = 0.41 e Å3
2234 reflectionsΔρmin = 0.35 e Å3
137 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
Br10.06150 (6)0.57510 (2)0.36727 (2)0.05871 (14)
S10.74473 (12)0.10243 (5)0.40740 (4)0.03706 (17)
O10.3779 (4)0.23972 (17)0.56688 (14)0.0606 (6)
O20.5116 (4)0.05733 (15)0.37692 (14)0.0529 (5)
O30.9592 (4)0.03989 (16)0.40469 (14)0.0555 (6)
N10.7895 (4)0.21290 (17)0.35343 (14)0.0385 (5)
C10.6129 (4)0.29366 (19)0.35581 (16)0.0326 (6)
C20.5631 (5)0.3622 (2)0.28382 (19)0.0403 (6)
H20.64300.35250.23320.048*
C30.3980 (5)0.4437 (2)0.2866 (2)0.0430 (7)
H30.36500.48820.23780.052*
C40.2814 (5)0.4595 (2)0.36193 (19)0.0409 (6)
C50.3200 (5)0.3919 (2)0.43312 (19)0.0416 (6)
H50.23680.40240.48290.050*
C60.4846 (4)0.3073 (2)0.43087 (17)0.0362 (6)
C70.5129 (5)0.2357 (2)0.50864 (18)0.0407 (6)
C80.7204 (5)0.1553 (2)0.51326 (17)0.0419 (6)
H8A0.68840.09890.55400.050*
H8B0.87450.18910.53550.050*
C90.9601 (4)0.2116 (2)0.28524 (19)0.0415 (6)
H9A0.87980.18120.23160.062*
H9B1.10240.17010.30570.062*
H9C1.01020.28260.27370.062*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0680 (2)0.0468 (2)0.0609 (2)0.02306 (14)0.00505 (16)0.00177 (15)
S10.0439 (3)0.0358 (4)0.0327 (4)0.0072 (3)0.0098 (3)0.0042 (3)
O10.0815 (14)0.0670 (14)0.0380 (12)0.0261 (11)0.0282 (11)0.0127 (11)
O20.0603 (12)0.0441 (12)0.0541 (14)0.0125 (9)0.0050 (10)0.0006 (10)
O30.0652 (12)0.0557 (13)0.0489 (13)0.0284 (10)0.0214 (10)0.0133 (10)
N10.0420 (11)0.0415 (13)0.0350 (13)0.0070 (9)0.0179 (10)0.0092 (10)
C10.0345 (12)0.0319 (14)0.0317 (15)0.0013 (10)0.0052 (10)0.0010 (11)
C20.0446 (14)0.0398 (15)0.0382 (17)0.0001 (11)0.0127 (12)0.0070 (12)
C30.0523 (15)0.0346 (15)0.0423 (17)0.0010 (12)0.0061 (13)0.0102 (12)
C40.0426 (13)0.0343 (14)0.0453 (18)0.0060 (11)0.0026 (12)0.0001 (13)
C50.0483 (15)0.0431 (15)0.0347 (16)0.0084 (12)0.0104 (12)0.0017 (13)
C60.0415 (13)0.0386 (15)0.0288 (15)0.0030 (11)0.0051 (11)0.0017 (11)
C70.0502 (14)0.0431 (16)0.0296 (15)0.0072 (12)0.0080 (12)0.0006 (12)
C80.0523 (15)0.0464 (17)0.0274 (15)0.0104 (12)0.0058 (12)0.0057 (12)
C90.0403 (13)0.0444 (16)0.0425 (17)0.0026 (11)0.0171 (12)0.0018 (13)
Geometric parameters (Å, º) top
Br1—C41.898 (3)C3—C41.379 (4)
S1—O31.4169 (19)C3—H30.9300
S1—O21.424 (2)C4—C51.372 (4)
S1—N11.649 (2)C5—C61.400 (3)
S1—C81.753 (3)C5—H50.9300
O1—C71.209 (3)C6—C71.479 (4)
N1—C11.407 (3)C7—C81.518 (3)
N1—C91.463 (3)C8—H8A0.9700
C1—C21.395 (3)C8—H8B0.9700
C1—C61.407 (3)C9—H9A0.9600
C2—C31.373 (4)C9—H9B0.9600
C2—H20.9300C9—H9C0.9600
O3—S1—O2118.63 (13)C4—C5—C6120.1 (2)
O3—S1—N1106.93 (11)C4—C5—H5120.0
O2—S1—N1110.70 (12)C6—C5—H5120.0
O3—S1—C8112.54 (13)C5—C6—C1119.3 (2)
O2—S1—C8107.17 (13)C5—C6—C7117.4 (2)
N1—S1—C899.15 (12)C1—C6—C7123.2 (2)
C1—N1—C9121.1 (2)O1—C7—C6122.3 (2)
C1—N1—S1117.60 (16)O1—C7—C8120.3 (2)
C9—N1—S1118.62 (17)C6—C7—C8117.4 (2)
C2—C1—N1120.5 (2)C7—C8—S1110.06 (18)
C2—C1—C6118.8 (2)C7—C8—H8A109.6
N1—C1—C6120.8 (2)S1—C8—H8A109.6
C3—C2—C1121.1 (2)C7—C8—H8B109.6
C3—C2—H2119.5S1—C8—H8B109.6
C1—C2—H2119.5H8A—C8—H8B108.2
C2—C3—C4119.8 (3)N1—C9—H9A109.5
C2—C3—H3120.1N1—C9—H9B109.5
C4—C3—H3120.1H9A—C9—H9B109.5
C5—C4—C3120.9 (2)N1—C9—H9C109.5
C5—C4—Br1119.3 (2)H9A—C9—H9C109.5
C3—C4—Br1119.8 (2)H9B—C9—H9C109.5
O3—S1—N1—C1172.74 (19)Br1—C4—C5—C6179.0 (2)
O2—S1—N1—C156.7 (2)C4—C5—C6—C11.2 (4)
C8—S1—N1—C155.7 (2)C4—C5—C6—C7178.3 (2)
O3—S1—N1—C925.6 (2)C2—C1—C6—C53.1 (4)
O2—S1—N1—C9105.0 (2)N1—C1—C6—C5176.5 (2)
C8—S1—N1—C9142.7 (2)C2—C1—C6—C7176.5 (2)
C9—N1—C1—C212.8 (4)N1—C1—C6—C73.9 (4)
S1—N1—C1—C2148.4 (2)C5—C6—C7—O19.9 (4)
C9—N1—C1—C6166.8 (2)C1—C6—C7—O1169.7 (3)
S1—N1—C1—C632.0 (3)C5—C6—C7—C8170.1 (2)
N1—C1—C2—C3177.5 (2)C1—C6—C7—C810.3 (4)
C6—C1—C2—C32.0 (4)O1—C7—C8—S1139.9 (2)
C1—C2—C3—C40.9 (4)C6—C7—C8—S140.0 (3)
C2—C3—C4—C52.8 (4)O3—S1—C8—C7170.50 (19)
C2—C3—C4—Br1177.9 (2)O2—S1—C8—C757.3 (2)
C3—C4—C5—C61.7 (4)N1—S1—C8—C757.8 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.932.543.308 (4)140
C8—H8A···O2ii0.972.543.470 (3)162
C9—H9B···O30.962.412.824 (3)106
C5—H5···Br1iii0.932.943.871 (3)175
C9—H9A···Br1iv0.963.013.871 (2)150
C9—H9C···Cg1v0.962.833.449 (3)123
Symmetry codes: (i) x+3/2, y+1/2, z+1/2; (ii) x+1, y, z+1; (iii) x, y+1, z+1; (iv) x+1/2, y1/2, z+1/2; (v) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC9H8BrNO3S
Mr290.13
Crystal system, space groupMonoclinic, P21/n
Temperature (K)296
a, b, c (Å)5.4577 (3), 12.6400 (8), 15.1258 (10)
β (°) 96.204 (2)
V3)1037.35 (11)
Z4
Radiation typeMo Kα
µ (mm1)4.15
Crystal size (mm)0.20 × 0.17 × 0.15
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.439, 0.540
No. of measured, independent and
observed [I > 2σ(I)] reflections
11077, 2234, 1709
Rint0.032
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.072, 1.04
No. of reflections2234
No. of parameters137
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.35

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.932.54003.308 (4)140.00
C8—H8A···O2ii0.972.54003.470 (3)162.00
C9—H9B···O30.962.41002.824 (3)106.00
C5—H5···Br1iii0.932.94403.871 (3)175.09
C9—H9A···Br1iv0.963.00953.871 (2)150.03
C9—H9C···Cg1v0.962.83003.449 (3)123.00
Symmetry codes: (i) x+3/2, y+1/2, z+1/2; (ii) x+1, y, z+1; (iii) x, y+1, z+1; (iv) x+1/2, y1/2, z+1/2; (v) x+1, y, z.
 

Acknowledgements

MS gratefully acknowledges the Higher Education Commission, Islamabad, Pakistan, for providing a Scholarship under the Indigenous PhD Program (PIN 042–120567-PS2–276).

References

First citationArshad, M. N., Tahir, M. N., Khan, I. U., Shafiq, M. & Siddiqui, W. A. (2008). Acta Cryst. E64, o2045.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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Volume 65| Part 5| May 2009| Page o1182
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