3-Chloro-6-[4-(2-pyrid­yl)piperazin-1-yl]pyridazine

Arslan, H.; Utku, S.; Hardcastle, K.I.; Gökçe, M.; Lense, S.

doi:10.1107/S1600536809050727

organic compounds

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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o35

doi:10.1107/S1600536809050727

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3-Chloro-6-[4-(2-pyridyl)piperazin-1-yl]pyridazine

Hakan Arslan,^a,^b ^* Semra Utku,^c Kenneth I. Hardcastle,^a Mehtap Gökçe ^d and Sheri Lense ^a

^aDepartment of Chemistry, Emory University, Atlanta, GA-30322, USA, ^bDepartment of Chemistry, Faculty of Pharmacy, Mersin University, Mersin TR-33169, Turkey, ^cDepartment of Pharmaceutical Chemistry, Faculty of Pharmacy, Mersin University, Mersin TR-33169, Turkey, and ^dDepartment of Pharmaceutical Chemistry, Faculty of Pharmacy, Gazi University, Ankara TR-06330, Turkey
^*Correspondence e-mail: hakan.arslan.acad@gmail.com

(Received 23 November 2009; accepted 25 November 2009; online 4 December 2009)

In the title compound, C₁₃H₁₄ClN₅, the piperazine ring adopts a chair conformation and the dihedral angle between the aromatic rings is 13.91 (7)°. The crystal structure is stabilized by weak intermolecular C—H⋯N hydrogen-bond interactions.

Related literature

For the synthesis, structures and analgesic and anti-inflammatory activity of substituted pyridazine derivatives, see: Boissier et al. (1963 ); Gokce et al. (2001 , 2004 , 2005 , 2009 ); Sahin et al. (2004 ); Dundar et al. (2007 ). For general background to non-opioid analgesic derivatives, see: Sato et al. (1981 ); Banoglu et al. (2004 ); Giovannoni et al. (2003 )·For puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₃H₁₄ClN₅
M_r = 275.74
Triclinic, $[P \overline 1]$
a = 5.912 (3) Å
b = 8.088 (5) Å
c = 13.689 (8) Å
α = 83.359 (9)°
β = 83.019 (9)°
γ = 75.168 (9)°
V = 625.5 (6) Å³
Z = 2
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 296 K
0.16 × 0.15 × 0.14 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.954, T_max = 0.959
11395 measured reflections
3275 independent reflections
2264 reflections with I > 2σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.095
S = 0.95
3275 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯N1ⁱ	0.93	2.58	3.346 (3)	140
Symmetry code: (i) x+1, y, z.

Data collection: APEX2 (Bruker (2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809050727/hg2610sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809050727/hg2610Isup2.hkl

checkCIF report

Comment top

The opioid derivative analgesics have significant side effects, therefore, the current research is focused on non-opioid analgesics that do not have serious side effects but are as effective as the opioids. One of the non-opioid analgesic derivatives is emorfazone which has a substituted pyridazine (Sato et al., 1981). In addition, some pyridazinone derivatives bearing an alkylpiperazinyl alkyl moiety also show interesting antinociceptive activity (Banoglu et al., 2004; Giovannoni et al., 2003).

Recently, our team focused on the synthesis, characterization, and analgesics-anti-inflammatory activity of substituted pyridazine derivatives (Dundar et al., 2007; Gokce et al., 2001, 2004, 2005, 2009; Sahin et al., 2004). The compound, 3-chloro-6-(4-pyridin-2-ylpiperazin-1-yl)pyridazine, (I), Scheme 1, is one example and in this article we report on the crystal structure of the title compound, Figure 1.

The molecular structure of (I) consists of 3-chloropyridazine and pyridine arms connected to a piperazine ring. The 3-chloropyridazine and pyridine rings are planar with a maximum deviation of 0.006 (1) Å for atom C4 and -0.014 (2) Å for atom C12. The dihedral angle between these two rings is 13.91 (7) °. The piperazine ring adopts a chair conformation. This is confirmed by the puckering parameters q₂ = 0.0056 (13) Å, q₃ = -0.5388 (13) Å, Q_T = 0.5388 (13) Å, θ = 179.67 (14) ° and ϕ = 221 (14) ° (Cremer & Pople, 1975).

The conformations of the 3-chloropyridazine and pyridine rings are best described by the torsion angles of -155.41 (12) ° and 156.51 (12) ° for C4—N3—C5—C6 and C9—N4—C7—C8, respectively; thus they adopt - antiperiplanar and + antiperiplanar conformations, respectively.

The crystal packing is dominated by weak intermolecular C3—H3···N1 (1 + x, y, z) hydrogen bonds, with H···N = 2.58 Å and a C—H···N angle of 140 ° (Figure 2).

Related literature top

For the synthesis, structures and analgesic and anti-inflammatory activity of substituted pyridazine derivatives, see: Boissier et al. (1963); Gokce et al. (2001, 2004, 2005, 2009); Sahin et al. (2004); Dundar et al. (2007). For general background to non-opioid analgesic derivatives, see: Sato et al. (1981); Banoglu et al. (2004); Giovannoni et al. (2003).For puckering parameters, see: Cremer & Pople (1975).

Experimental top

A mixture of 3,6-dichloropyridazine, (II), (1.7 mol) and 1-(2-pyridyl)piperazine, (III), (2.0 mol) in ethanol (10 ml) was heated under reflux for 4 h after which the mixture was cooled to room temperature (Figure 3) (Boissier et al., 1963). The resulting crude precipitate was filtered off and purified by repeated washing with small portions of cold ethanol. The precipitate formed was crystallized from CH₂Cl₂:ethanol (5:10) to give the compound 3-chloro-6-(4-pyridin-2-ylpiperazin-1-yl) pyridazine, (I), as white crystals. Yields: 0.270 g, 58%. M.p.: 153 °C. ¹H NMR (DMSO-d₆) δ: 8.16–8.13 (d, 1H, pyridyl), 7.63–7.56 (m, 2H, pyridyl), 7.47–7.44 (d, 1H, pyridazin), 6.93–6.89 (d, 1H, pyridyl), 6.75–6.66 (d, 1H, pyridazin), 3.73–3.62(m, 4H, piperazine), 3.17–3.14 (m, 4H, piperazine). MS (EI) m/z: 276 (M⁺). Anal. Calc. for C₁₃H₁₄N₅Cl: C, 56.63; H, 5.12; N, 25.40%. Found: C, 56.60; H, 5.10; N, 24.42%.

Computing details top

Data collection: APEX2 (Bruker (2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I), showing ellipsoids at the 50% probability level.
	Fig. 2. The molecular packing of (I). The hydrogen bonds are shown as dashed lines.
	Fig. 3. Preparation of compound (I)

3-Chloro-6-[4-(2-pyridyl)piperazin-1-yl]pyridazine top

Crystal data top

C₁₃H₁₄ClN₅	Z = 2
M_r = 275.74	F(000) = 288
Triclinic, P1	D_x = 1.464 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.912 (3) Å	Cell parameters from 2718 reflections
b = 8.088 (5) Å	θ = 2.6–28.2°
c = 13.689 (8) Å	µ = 0.30 mm⁻¹
α = 83.359 (9)°	T = 296 K
β = 83.019 (9)°	Block, colourless
γ = 75.168 (9)°	0.16 × 0.15 × 0.14 mm
V = 625.5 (6) Å³

Data collection top

Bruker APEXII CCD diffractometer	3275 independent reflections
Radiation source: fine-focus sealed tube	2264 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.049
ϕ and ω scans	θ_max = 29.0°, θ_min = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −8→7
T_min = 0.954, T_max = 0.959	k = −10→11
11395 measured reflections	l = −18→18

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.095	H-atom parameters constrained
S = 0.95	w = 1/[σ²(F_o²) + (0.0433P)²] where P = (F_o² + 2F_c²)/3
3275 reflections	(Δ/σ)_max = 0.001
172 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₃H₁₄ClN₅	γ = 75.168 (9)°
M_r = 275.74	V = 625.5 (6) Å³
Triclinic, P1	Z = 2
a = 5.912 (3) Å	Mo Kα radiation
b = 8.088 (5) Å	µ = 0.30 mm⁻¹
c = 13.689 (8) Å	T = 296 K
α = 83.359 (9)°	0.16 × 0.15 × 0.14 mm
β = 83.019 (9)°

Data collection top

Bruker APEXII CCD diffractometer	3275 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2264 reflections with I > 2σ(I)
T_min = 0.954, T_max = 0.959	R_int = 0.049
11395 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.095	H-atom parameters constrained
S = 0.95	Δρ_max = 0.27 e Å⁻³
3275 reflections	Δρ_min = −0.23 e Å⁻³
172 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
C1	0.2600 (3)	1.08679 (18)	0.14549 (10)	0.0258 (3)
C2	0.4977 (3)	1.05027 (18)	0.15814 (10)	0.0262 (3)
H2	0.6045	1.0856	0.1098	0.031*
C3	0.5676 (2)	0.96086 (18)	0.24396 (10)	0.0233 (3)
H3	0.7248	0.9314	0.2563	0.028*
C4	0.3929 (2)	0.91394 (16)	0.31412 (10)	0.0183 (3)
C5	0.2554 (2)	0.78257 (18)	0.47211 (9)	0.0191 (3)
H5A	0.2447	0.6710	0.4565	0.023*
H5B	0.1066	0.8639	0.4613	0.023*
C6	0.2997 (2)	0.77262 (18)	0.57925 (10)	0.0201 (3)
H6A	0.2902	0.8869	0.5973	0.024*
H6B	0.1795	0.7281	0.6206	0.024*
C7	0.7198 (2)	0.71363 (18)	0.53092 (9)	0.0195 (3)
H7A	0.8676	0.6312	0.5417	0.023*
H7B	0.7325	0.8246	0.5467	0.023*
C8	0.6760 (2)	0.72468 (17)	0.42325 (10)	0.0191 (3)
H8A	0.7957	0.7701	0.3822	0.023*
H8B	0.6860	0.6107	0.4047	0.023*
C9	0.5772 (2)	0.58513 (17)	0.69070 (10)	0.0195 (3)
C10	0.3966 (3)	0.57581 (19)	0.76644 (11)	0.0273 (3)
H10	0.2411	0.6307	0.7571	0.033*
C11	0.4545 (3)	0.4840 (2)	0.85437 (11)	0.0326 (4)
H11	0.3373	0.4754	0.9052	0.039*
C12	0.6857 (3)	0.4044 (2)	0.86779 (11)	0.0335 (4)
H12	0.7277	0.3393	0.9263	0.040*
C13	0.8513 (3)	0.4253 (2)	0.79115 (11)	0.0317 (4)
H13	1.0080	0.3743	0.8002	0.038*
Cl1	0.15611 (8)	1.19962 (6)	0.03723 (3)	0.04376 (16)
N1	0.1002 (2)	1.04206 (16)	0.21036 (9)	0.0273 (3)
N2	0.1664 (2)	0.95301 (15)	0.29644 (8)	0.0240 (3)
N3	0.44321 (19)	0.83591 (14)	0.40660 (8)	0.0185 (3)
N4	0.53064 (19)	0.66186 (14)	0.59658 (8)	0.0190 (3)
N5	0.8031 (2)	0.51407 (15)	0.70410 (9)	0.0259 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0272 (8)	0.0267 (8)	0.0218 (7)	−0.0052 (6)	−0.0029 (6)	0.0016 (6)
C2	0.0253 (8)	0.0305 (8)	0.0236 (7)	−0.0119 (7)	0.0053 (6)	−0.0019 (6)
C3	0.0171 (7)	0.0278 (8)	0.0256 (7)	−0.0084 (6)	0.0024 (6)	−0.0035 (6)
C4	0.0171 (7)	0.0169 (7)	0.0215 (7)	−0.0052 (5)	0.0011 (5)	−0.0050 (5)
C5	0.0120 (7)	0.0230 (7)	0.0219 (7)	−0.0054 (6)	0.0007 (5)	−0.0006 (5)
C6	0.0129 (7)	0.0240 (7)	0.0220 (7)	−0.0033 (6)	0.0015 (5)	−0.0015 (6)
C7	0.0121 (7)	0.0226 (7)	0.0239 (7)	−0.0057 (6)	−0.0001 (5)	−0.0010 (5)
C8	0.0107 (7)	0.0217 (7)	0.0239 (7)	−0.0031 (5)	0.0017 (5)	−0.0028 (5)
C9	0.0198 (7)	0.0182 (7)	0.0219 (7)	−0.0057 (6)	−0.0031 (6)	−0.0033 (5)
C10	0.0208 (8)	0.0327 (8)	0.0262 (8)	−0.0048 (7)	−0.0005 (6)	0.0011 (6)
C11	0.0320 (9)	0.0415 (9)	0.0236 (8)	−0.0123 (8)	0.0016 (7)	0.0023 (7)
C12	0.0369 (10)	0.0389 (9)	0.0240 (8)	−0.0077 (8)	−0.0103 (7)	0.0045 (7)
C13	0.0246 (9)	0.0378 (9)	0.0314 (8)	−0.0030 (7)	−0.0101 (7)	0.0000 (7)
Cl1	0.0423 (3)	0.0562 (3)	0.0281 (2)	−0.0095 (2)	−0.00750 (18)	0.01386 (18)
N1	0.0230 (7)	0.0329 (7)	0.0246 (6)	−0.0060 (6)	−0.0038 (5)	0.0034 (5)
N2	0.0166 (6)	0.0297 (7)	0.0242 (6)	−0.0054 (5)	−0.0023 (5)	0.0033 (5)
N3	0.0115 (6)	0.0229 (6)	0.0198 (6)	−0.0039 (5)	0.0009 (4)	0.0001 (5)
N4	0.0119 (6)	0.0230 (6)	0.0209 (6)	−0.0042 (5)	0.0003 (5)	0.0007 (5)
N5	0.0201 (7)	0.0307 (7)	0.0259 (7)	−0.0037 (5)	−0.0052 (5)	−0.0014 (5)

Geometric parameters (Å, º) top

C1—N1	1.3071 (19)	C7—H7A	0.9700
C1—C2	1.388 (2)	C7—H7B	0.9700
C1—Cl1	1.7401 (16)	C8—N3	1.4661 (18)
C2—C3	1.3574 (19)	C8—H8A	0.9700
C2—H2	0.9300	C8—H8B	0.9700
C3—C4	1.4170 (18)	C9—N5	1.3377 (18)
C3—H3	0.9300	C9—N4	1.3909 (17)
C4—N2	1.3401 (18)	C9—C10	1.405 (2)
C4—N3	1.3784 (17)	C10—C11	1.372 (2)
C5—N3	1.4617 (17)	C10—H10	0.9300
C5—C6	1.5104 (19)	C11—C12	1.378 (2)
C5—H5A	0.9700	C11—H11	0.9300
C5—H5B	0.9700	C12—C13	1.372 (2)
C6—N4	1.4582 (18)	C12—H12	0.9300
C6—H6A	0.9700	C13—N5	1.3402 (18)
C6—H6B	0.9700	C13—H13	0.9300
C7—N4	1.4635 (17)	N1—N2	1.3534 (16)
C7—C8	1.5159 (19)

N1—C1—C2	124.64 (13)	N3—C8—C7	110.54 (11)
N1—C1—Cl1	115.24 (12)	N3—C8—H8A	109.5
C2—C1—Cl1	120.12 (11)	C7—C8—H8A	109.5
C3—C2—C1	117.20 (13)	N3—C8—H8B	109.5
C3—C2—H2	121.4	C7—C8—H8B	109.5
C1—C2—H2	121.4	H8A—C8—H8B	108.1
C2—C3—C4	117.76 (14)	N5—C9—N4	116.30 (12)
C2—C3—H3	121.1	N5—C9—C10	121.67 (13)
C4—C3—H3	121.1	N4—C9—C10	121.97 (13)
N2—C4—N3	116.16 (11)	C11—C10—C9	118.58 (14)
N2—C4—C3	121.66 (12)	C11—C10—H10	120.7
N3—C4—C3	122.04 (13)	C9—C10—H10	120.7
N3—C5—C6	111.31 (11)	C10—C11—C12	120.29 (14)
N3—C5—H5A	109.4	C10—C11—H11	119.9
C6—C5—H5A	109.4	C12—C11—H11	119.9
N3—C5—H5B	109.4	C13—C12—C11	117.17 (14)
C6—C5—H5B	109.4	C13—C12—H12	121.4
H5A—C5—H5B	108.0	C11—C12—H12	121.4
N4—C6—C5	110.91 (11)	N5—C13—C12	124.63 (14)
N4—C6—H6A	109.5	N5—C13—H13	117.7
C5—C6—H6A	109.5	C12—C13—H13	117.7
N4—C6—H6B	109.5	C1—N1—N2	119.04 (12)
C5—C6—H6B	109.5	C4—N2—N1	119.68 (11)
H6A—C6—H6B	108.0	C4—N3—C5	118.35 (11)
N4—C7—C8	111.62 (11)	C4—N3—C8	121.18 (11)
N4—C7—H7A	109.3	C5—N3—C8	112.41 (11)
C8—C7—H7A	109.3	C9—N4—C6	120.47 (11)
N4—C7—H7B	109.3	C9—N4—C7	118.98 (11)
C8—C7—H7B	109.3	C6—N4—C7	112.49 (11)
H7A—C7—H7B	108.0	C9—N5—C13	117.56 (12)

N1—C1—C2—C3	0.4 (2)	C3—C4—N3—C5	−176.37 (12)
Cl1—C1—C2—C3	−179.57 (11)	N2—C4—N3—C8	154.15 (12)
C1—C2—C3—C4	−0.8 (2)	C3—C4—N3—C8	−30.0 (2)
C2—C3—C4—N2	1.2 (2)	C6—C5—N3—C4	−155.41 (12)
C2—C3—C4—N3	−174.44 (13)	C6—C5—N3—C8	55.41 (15)
N3—C5—C6—N4	−54.49 (15)	C7—C8—N3—C4	157.23 (12)
N4—C7—C8—N3	53.56 (15)	C7—C8—N3—C5	−54.57 (15)
N5—C9—C10—C11	−3.3 (2)	N5—C9—N4—C6	−167.32 (12)
N4—C9—C10—C11	173.85 (13)	C10—C9—N4—C6	15.4 (2)
C9—C10—C11—C12	0.6 (2)	N5—C9—N4—C7	−20.90 (18)
C10—C11—C12—C13	1.6 (3)	C10—C9—N4—C7	161.84 (13)
C11—C12—C13—N5	−1.5 (3)	C5—C6—N4—C9	−156.99 (12)
C2—C1—N1—N2	−0.3 (2)	C5—C6—N4—C7	54.58 (15)
Cl1—C1—N1—N2	179.64 (10)	C8—C7—N4—C9	156.51 (12)
N3—C4—N2—N1	174.73 (12)	C8—C7—N4—C6	−54.56 (15)
C3—C4—N2—N1	−1.2 (2)	N4—C9—N5—C13	−173.88 (13)
C1—N1—N2—C4	0.7 (2)	C10—C9—N5—C13	3.4 (2)
N2—C4—N3—C5	7.76 (18)	C12—C13—N5—C9	−1.0 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···N1ⁱ	0.93	2.58	3.346 (3)	140

Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₄ClN₅
M_r	275.74
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	5.912 (3), 8.088 (5), 13.689 (8)
α, β, γ (°)	83.359 (9), 83.019 (9), 75.168 (9)
V (Å³)	625.5 (6)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.16 × 0.15 × 0.14

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.954, 0.959
No. of measured, independent and observed [I > 2σ(I)] reflections	11395, 3275, 2264
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.682

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.095, 0.95
No. of reflections	3275
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.23

Computer programs: APEX2 (Bruker (2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···N1ⁱ	0.93	2.58	3.346 (3)	140

Symmetry code: (i) x+1, y, z.

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Volume 66| Part 1| January 2010| Page o35

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