Ethyl 6-methyl-2-p-tolyl­pyrazolo[1,5-a]pyridine-5-carboxyl­ate

Jia, J.; Ge, Y.; Zhao, G.; Wang, J.

doi:10.1107/S1600536809035314

organic compounds

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Volume 65| Part 10| October 2009| Page o2372

doi:10.1107/S1600536809035314

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Ethyl 6-methyl-2-p-tolylpyrazolo[1,5-a]pyridine-5-carboxylate

Jiong Jia,^a Yan-qing Ge,^a Gui-long Zhao ^a and Jian-wu Wang ^a ^*

^aSchool of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
^*Correspondence e-mail: yugp2005@yahoo.com.cn

(Received 29 August 2009; accepted 1 September 2009; online 9 September 2009)

In the title molecule, C₁₈H₁₈N₂O₂, the bicyclic ring system and the benzene ring form a dihedral angle of 13.45 (3)°. In the crystal structure, weak intermolecular C—H⋯O hydrogen bonds link molecules into chains propagated along [201].

Related literature

For novel pyrazolo[1,5-a]pyridine compounds, see: Ge et al. (2009 ). For a related structure, see: Shao et al. (2009 ).

Experimental

Crystal data

C₁₈H₁₈N₂O₂
M_r = 294.34
Monoclinic, P 2₁ /c
a = 6.8352 (3) Å
b = 30.3999 (11) Å
c = 7.5409 (3) Å
β = 97.375 (2)°
V = 1553.96 (11) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.43 × 0.32 × 0.21 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.965, T_max = 0.983
18651 measured reflections
3181 independent reflections
2166 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.056
wR(F²) = 0.148
S = 1.07
3181 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9A⋯O3ⁱ	0.93	2.42	3.339 (3)	170
Symmetry code: (i) $[x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1999 ); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809035314/cv2611sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809035314/cv2611Isup2.hkl

checkCIF report

Comment top

The pyrazolo[1,5-a]pyridine derivatives have been of interest for their pharmacological and biological activities. Considerable efforts of our group have been devoted to the development of novel pyrazolo[1,5-a]pyridine compounds(Ge et al., 2009). In continuation of this work, we report here the crystal structure of the title compound, (I) (Fig. 1).

In (I), all bond lengths are normal and in a good agreement with those reported previously (Shao et al., 2009). Atoms O2/O3/C15/C16/C17/C18 lie in 1H-pyrazolo[1,5-a]pyridine (C8—C14/N1/N2) plane with the maximum deviation of 0.065 (3) Å for O2. The 1H-pyrazolo[1,5-a]pyridine plane forms dihedral angle of 13.45 (3)° with the benzene ring (C2—C7).

In the crystal structure, weak intermolecular C–H···O hydrogen bond (Table 1) link the molecules into chains propagated in direction [201].

Related literature top

For novel pyrazolo[1,5-a]pyridine compounds, see: Ge et al. (2009). For arelated structure, see: Shao et al. (2009).

Experimental top

To a 50-ml round-bottomed flask were added 3-p-tolyl-1H-pyrazole-5-carbaldehyde(6.0 mmol), ethyl 4-bromo-3-methylbut-2-enoate (7.2 mmol), potassium carbonate (1.60 g, 12.5 mmol) and DMF (10 mL). The mixture was stirred at rt for 8 h and then filtered. The filtrate was poured into water (100 ml) and extracted with CH₂Cl₂ (3 x 30 ml). The combined extracts were washed with water (2 x 50 ml), dried over anhydrous MgSO4 and filtered, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography (yield 75%). Crystals of (I) suitable for X-ray diffraction were obtained by slow cooling of the refluxed solution of the product in ethyl acetate at room temperature for 2 d.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. View of the title compound, with displacement ellipsoids drawn at the 40% probability level.

Ethyl 6-methyl-2-p-tolylpyrazolo[1,5-a]pyridine-5-carboxylate top

Crystal data top

C₁₈H₁₈N₂O₂	F(000) = 624
M_r = 294.34	D_x = 1.258 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4574 reflections
a = 6.8352 (3) Å	θ = 2.7–24.2°
b = 30.3999 (11) Å	µ = 0.08 mm⁻¹
c = 7.5409 (3) Å	T = 293 K
β = 97.375 (2)°	Block, colourless
V = 1553.96 (11) Å³	0.43 × 0.32 × 0.21 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	3181 independent reflections
Radiation source: fine-focus sealed tube	2166 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 26.3°, θ_min = 1.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→8
T_min = 0.965, T_max = 0.983	k = −37→37
18651 measured reflections	l = −9→9

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.148	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0589P)² + 0.5452P] where P = (F_o² + 2F_c²)/3
3181 reflections	(Δ/σ)_max < 0.001
199 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₈H₁₈N₂O₂	V = 1553.96 (11) Å³
M_r = 294.34	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.8352 (3) Å	µ = 0.08 mm⁻¹
b = 30.3999 (11) Å	T = 293 K
c = 7.5409 (3) Å	0.43 × 0.32 × 0.21 mm
β = 97.375 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	3181 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2166 reflections with I > 2σ(I)
T_min = 0.965, T_max = 0.983	R_int = 0.036
18651 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.056	0 restraints
wR(F²) = 0.148	H-atom parameters constrained
S = 1.07	Δρ_max = 0.23 e Å⁻³
3181 reflections	Δρ_min = −0.22 e Å⁻³
199 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

	x	y	z	U_iso*/U_eq
N1	0.3372 (2)	0.65607 (5)	0.5370 (2)	0.0429 (4)
N2	0.3988 (2)	0.61395 (6)	0.5589 (2)	0.0482 (4)
O2	0.3651 (2)	0.81645 (4)	0.5569 (2)	0.0561 (4)
O3	0.0666 (3)	0.80858 (6)	0.4073 (3)	0.0806 (6)
C1	1.0771 (5)	0.46224 (8)	0.7690 (4)	0.0820 (8)
H1A	1.2123	0.4711	0.7975	0.123*
H1B	1.0627	0.4450	0.6615	0.123*
H1C	1.0386	0.4450	0.8654	0.123*
C2	0.9475 (4)	0.50258 (8)	0.7418 (3)	0.0589 (6)
C3	1.0264 (4)	0.54415 (8)	0.7553 (3)	0.0638 (6)
H3A	1.1619	0.5474	0.7852	0.077*
C4	0.9101 (3)	0.58130 (7)	0.7255 (3)	0.0563 (6)
H4A	0.9683	0.6090	0.7366	0.068*
C5	0.7080 (3)	0.57786 (6)	0.6794 (3)	0.0460 (5)
C6	0.6282 (4)	0.53587 (7)	0.6683 (3)	0.0636 (6)
H6A	0.4927	0.5324	0.6392	0.076*
C7	0.7463 (4)	0.49920 (8)	0.6995 (4)	0.0695 (7)
H7A	0.6885	0.4715	0.6918	0.083*
C8	0.5871 (3)	0.61754 (6)	0.6386 (3)	0.0435 (5)
C9	0.6428 (3)	0.66109 (7)	0.6684 (3)	0.0464 (5)
H9A	0.7643	0.6714	0.7221	0.056*
C10	0.4813 (3)	0.68603 (6)	0.6023 (3)	0.0423 (5)
C11	0.4335 (3)	0.73089 (6)	0.5842 (3)	0.0440 (5)
H11A	0.5260	0.7519	0.6288	0.053*
C12	0.2535 (3)	0.74423 (7)	0.5024 (2)	0.0412 (5)
C13	0.1075 (3)	0.71204 (7)	0.4353 (3)	0.0441 (5)
C14	0.1553 (3)	0.66890 (7)	0.4564 (3)	0.0473 (5)
H14A	0.0628	0.6476	0.4153	0.057*
C15	−0.0942 (3)	0.72349 (8)	0.3412 (3)	0.0557 (6)
H15A	−0.1660	0.6970	0.3083	0.084*
H15B	−0.0807	0.7403	0.2357	0.084*
H15C	−0.1644	0.7405	0.4197	0.084*
C16	0.2140 (3)	0.79236 (7)	0.4827 (3)	0.0476 (5)
C17	0.3473 (4)	0.86376 (7)	0.5387 (3)	0.0624 (6)
H17A	0.2408	0.8744	0.6007	0.075*
H17B	0.3190	0.8718	0.4135	0.075*
C18	0.5387 (4)	0.88348 (8)	0.6182 (3)	0.0757 (8)
H18A	0.5313	0.9149	0.6078	0.114*
H18B	0.6429	0.8727	0.5557	0.114*
H18C	0.5649	0.8755	0.7421	0.114*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0375 (9)	0.0432 (10)	0.0472 (9)	−0.0043 (7)	0.0016 (7)	−0.0009 (7)
N2	0.0473 (10)	0.0404 (10)	0.0560 (10)	−0.0027 (8)	0.0035 (8)	−0.0002 (8)
O2	0.0546 (9)	0.0407 (9)	0.0710 (10)	−0.0009 (7)	0.0008 (7)	0.0056 (7)
O3	0.0562 (10)	0.0558 (11)	0.1210 (15)	0.0076 (8)	−0.0225 (10)	0.0140 (10)
C1	0.101 (2)	0.0602 (17)	0.0863 (19)	0.0314 (15)	0.0167 (16)	0.0084 (14)
C2	0.0711 (17)	0.0490 (14)	0.0574 (13)	0.0134 (12)	0.0116 (11)	0.0033 (10)
C3	0.0520 (14)	0.0598 (16)	0.0790 (17)	0.0093 (12)	0.0058 (12)	0.0061 (12)
C4	0.0516 (13)	0.0448 (13)	0.0719 (15)	0.0004 (10)	0.0062 (11)	0.0037 (11)
C5	0.0476 (12)	0.0423 (12)	0.0487 (11)	0.0007 (9)	0.0078 (9)	−0.0003 (9)
C6	0.0553 (14)	0.0488 (14)	0.0850 (17)	−0.0039 (11)	0.0027 (12)	−0.0019 (12)
C7	0.0785 (18)	0.0384 (13)	0.0909 (19)	−0.0012 (12)	0.0081 (14)	0.0013 (12)
C8	0.0414 (11)	0.0436 (12)	0.0454 (11)	−0.0024 (9)	0.0050 (9)	0.0006 (9)
C9	0.0388 (11)	0.0441 (12)	0.0547 (12)	−0.0031 (9)	−0.0007 (9)	0.0001 (9)
C10	0.0372 (10)	0.0432 (12)	0.0455 (11)	−0.0049 (9)	0.0022 (8)	−0.0004 (8)
C11	0.0405 (11)	0.0407 (11)	0.0500 (11)	−0.0051 (9)	0.0022 (9)	−0.0001 (9)
C12	0.0374 (10)	0.0451 (12)	0.0411 (10)	−0.0001 (9)	0.0045 (8)	0.0038 (8)
C13	0.0361 (10)	0.0534 (13)	0.0425 (11)	−0.0011 (9)	0.0036 (8)	0.0030 (9)
C14	0.0367 (11)	0.0533 (13)	0.0502 (12)	−0.0071 (9)	−0.0008 (9)	−0.0013 (9)
C15	0.0408 (12)	0.0626 (14)	0.0609 (14)	−0.0007 (10)	−0.0042 (10)	0.0036 (11)
C16	0.0406 (11)	0.0510 (13)	0.0512 (12)	0.0006 (10)	0.0055 (9)	0.0055 (10)
C17	0.0741 (17)	0.0418 (13)	0.0731 (16)	0.0030 (12)	0.0157 (13)	0.0056 (11)
C18	0.094 (2)	0.0588 (16)	0.0740 (17)	−0.0194 (14)	0.0101 (15)	−0.0054 (13)

Geometric parameters (Å, º) top

N1—N2	1.351 (2)	C7—H7A	0.9300
N1—C14	1.369 (2)	C8—C9	1.388 (3)
N1—C10	1.385 (2)	C9—C10	1.379 (3)
N2—C8	1.353 (2)	C9—H9A	0.9300
O2—C16	1.330 (2)	C10—C11	1.405 (3)
O2—C17	1.448 (3)	C11—C12	1.365 (3)
O3—C16	1.198 (2)	C11—H11A	0.9300
C1—C2	1.511 (3)	C12—C13	1.442 (3)
C1—H1A	0.9600	C12—C16	1.492 (3)
C1—H1B	0.9600	C13—C14	1.356 (3)
C1—H1C	0.9600	C13—C15	1.508 (3)
C2—C3	1.373 (3)	C14—H14A	0.9300
C2—C7	1.375 (4)	C15—H15A	0.9600
C3—C4	1.383 (3)	C15—H15B	0.9600
C3—H3A	0.9300	C15—H15C	0.9600
C4—C5	1.384 (3)	C17—C18	1.493 (3)
C4—H4A	0.9300	C17—H17A	0.9700
C5—C6	1.386 (3)	C17—H17B	0.9700
C5—C8	1.472 (3)	C18—H18A	0.9600
C6—C7	1.379 (3)	C18—H18B	0.9600
C6—H6A	0.9300	C18—H18C	0.9600

N2—N1—C14	125.13 (17)	C9—C10—C11	137.25 (19)
N2—N1—C10	112.56 (16)	N1—C10—C11	117.27 (17)
C14—N1—C10	122.30 (17)	C12—C11—C10	121.13 (18)
N1—N2—C8	103.98 (15)	C12—C11—H11A	119.4
C16—O2—C17	117.10 (17)	C10—C11—H11A	119.4
C2—C1—H1A	109.5	C11—C12—C13	120.00 (19)
C2—C1—H1B	109.5	C11—C12—C16	118.51 (18)
H1A—C1—H1B	109.5	C13—C12—C16	121.49 (17)
C2—C1—H1C	109.5	C14—C13—C12	117.99 (18)
H1A—C1—H1C	109.5	C14—C13—C15	118.08 (18)
H1B—C1—H1C	109.5	C12—C13—C15	123.93 (19)
C3—C2—C7	117.3 (2)	C13—C14—N1	121.30 (19)
C3—C2—C1	121.3 (2)	C13—C14—H14A	119.3
C7—C2—C1	121.5 (2)	N1—C14—H14A	119.3
C2—C3—C4	121.8 (2)	C13—C15—H15A	109.5
C2—C3—H3A	119.1	C13—C15—H15B	109.5
C4—C3—H3A	119.1	H15A—C15—H15B	109.5
C3—C4—C5	120.9 (2)	C13—C15—H15C	109.5
C3—C4—H4A	119.6	H15A—C15—H15C	109.5
C5—C4—H4A	119.6	H15B—C15—H15C	109.5
C4—C5—C6	117.2 (2)	O3—C16—O2	122.3 (2)
C4—C5—C8	120.38 (19)	O3—C16—C12	125.6 (2)
C6—C5—C8	122.4 (2)	O2—C16—C12	112.17 (17)
C7—C6—C5	121.1 (2)	O2—C17—C18	107.6 (2)
C7—C6—H6A	119.4	O2—C17—H17A	110.2
C5—C6—H6A	119.4	C18—C17—H17A	110.2
C2—C7—C6	121.7 (2)	O2—C17—H17B	110.2
C2—C7—H7A	119.2	C18—C17—H17B	110.2
C6—C7—H7A	119.2	H17A—C17—H17B	108.5
N2—C8—C9	111.98 (17)	C17—C18—H18A	109.5
N2—C8—C5	120.22 (18)	C17—C18—H18B	109.5
C9—C8—C5	127.78 (18)	H18A—C18—H18B	109.5
C10—C9—C8	106.01 (17)	C17—C18—H18C	109.5
C10—C9—H9A	127.0	H18A—C18—H18C	109.5
C8—C9—H9A	127.0	H18B—C18—H18C	109.5
C9—C10—N1	105.47 (17)

C14—N1—N2—C8	178.09 (17)	C14—N1—C10—C9	−178.47 (17)
C10—N1—N2—C8	−0.5 (2)	N2—N1—C10—C11	179.20 (16)
C7—C2—C3—C4	−0.8 (4)	C14—N1—C10—C11	0.5 (3)
C1—C2—C3—C4	178.1 (2)	C9—C10—C11—C12	177.3 (2)
C2—C3—C4—C5	−0.5 (4)	N1—C10—C11—C12	−1.3 (3)
C3—C4—C5—C6	1.3 (3)	C10—C11—C12—C13	1.0 (3)
C3—C4—C5—C8	−176.7 (2)	C10—C11—C12—C16	−178.23 (18)
C4—C5—C6—C7	−0.9 (4)	C11—C12—C13—C14	0.0 (3)
C8—C5—C6—C7	177.0 (2)	C16—C12—C13—C14	179.22 (18)
C3—C2—C7—C6	1.2 (4)	C11—C12—C13—C15	−179.27 (19)
C1—C2—C7—C6	−177.6 (2)	C16—C12—C13—C15	−0.1 (3)
C5—C6—C7—C2	−0.4 (4)	C12—C13—C14—N1	−0.7 (3)
N1—N2—C8—C9	0.7 (2)	C15—C13—C14—N1	178.58 (18)
N1—N2—C8—C5	−178.00 (17)	N2—N1—C14—C13	−178.02 (18)
C4—C5—C8—N2	166.40 (19)	C10—N1—C14—C13	0.5 (3)
C6—C5—C8—N2	−11.4 (3)	C17—O2—C16—O3	−1.8 (3)
C4—C5—C8—C9	−12.0 (3)	C17—O2—C16—C12	177.15 (17)
C6—C5—C8—C9	170.1 (2)	C11—C12—C16—O3	176.6 (2)
N2—C8—C9—C10	−0.6 (2)	C13—C12—C16—O3	−2.6 (3)
C5—C8—C9—C10	177.97 (19)	C11—C12—C16—O2	−2.3 (3)
C8—C9—C10—N1	0.2 (2)	C13—C12—C16—O2	178.51 (17)
C8—C9—C10—C11	−178.5 (2)	C16—O2—C17—C18	−175.41 (18)
N2—N1—C10—C9	0.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9A···O3ⁱ	0.93	2.42	3.339 (3)	170

Symmetry code: (i) x+1, −y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₈N₂O₂
M_r	294.34
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	6.8352 (3), 30.3999 (11), 7.5409 (3)
β (°)	97.375 (2)
V (Å³)	1553.96 (11)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.43 × 0.32 × 0.21

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.965, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	18651, 3181, 2166
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.624

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.056, 0.148, 1.07
No. of reflections	3181
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.22

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1999), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9A···O3ⁱ	0.93	2.42	3.339 (3)	170.0

Symmetry code: (i) x+1, −y+3/2, z+1/2.

References

Bruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Ge, Y. Q., Jia, J., Li, Y., Yin, L. & Wang, J. W. (2009). Heterocycles, 78, 197–206. CAS Google Scholar
Shao, T., Zhao, G. & Wang, J. (2009). Acta Cryst. E65, o923. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar

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Volume 65| Part 10| October 2009| Page o2372

doi:10.1107/S1600536809035314

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