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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 11| November 2014| Pages o1212-o1213

Crystal structure of 5-(4,5-di­hydro-1H-imidazol-2-yl)-3-methyl-1-phenyl-1H-pyrazolo­[3,4-b]pyrazin-6-amine

aDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA, bChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, cChemistry Department, Faculty of Science, Minia University, 61519 El-Minia, Egypt, dDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, eDepartment of Chemistry, Faculty of Science, Assiut University, 71515 Assiut, Egypt, and fKirkuk University, College of Science, Department of Chemistry, Kirkuk, Iraq
*Correspondence e-mail: shaabankamel@yahoo.com

Edited by P. C. Healy, Griffith University, Australia (Received 23 October 2014; accepted 27 October 2014; online 31 October 2014)

In the title compound, C15H15N7, the phenyl ring is inclined by 19.86 (5)° to the mean plane of the pyrazolo­[3,4-b]pyrazine core. In the crystal, N—H⋯N and C—H⋯N hydrogen bonds form [010] chains, which stack via ππ inter­actions [centroid–centroid distance between the pyrazole rings = 3.4322 (7) Å].

1. Related literature

For the synthesis of similar pyrazolo­[3,4-b]pyrazines, see: El-Emary & El-Kashef (2013[El-Emary, T. I. & El-Kashef, H. (2013). Eur. J. Med. Chem. 62, 478-485.]). For different biological and industrial applications of pyrazolo­pyrazine scaffold compounds, see: El-Emary et al. (1998[El-Emary, T. I., El-Dean, A. M. K. & El-Kashef, H. S. (1998). Farmaco, 53, 383-388.]); El-Kashef et al. (2000[El-Kashef, H. S., El-Emary, T. I., Gasquet, M., Timon-David, P., Maldonado, J. & Vanelle, P. (2000). Pharmazie, 55, 572-576.]); El-Emary (2006[El-Emary, T. I. (2006). J. Chin. Chem. Soc. 53, 391-401.]); Rangnekar (1990[Rangnekar, D. W. (1990). J. Chem. Technol. Biotechnol. 49, 311-320.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C15H15N7

  • Mr = 293.34

  • Monoclinic, C 2/c

  • a = 7.9412 (2) Å

  • b = 15.7078 (3) Å

  • c = 22.3276 (4) Å

  • β = 98.573 (1)°

  • V = 2754.00 (10) Å3

  • Z = 8

  • Cu Kα radiation

  • μ = 0.75 mm−1

  • T = 150 K

  • 0.15 × 0.10 × 0.05 mm

2.2. Data collection

  • Bruker D8 VENTURE PHOTON 100 CMOS diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]) Tmin = 0.93, Tmax = 0.97

  • 21033 measured reflections

  • 2685 independent reflections

  • 2335 reflections with I > 2σ(I)

  • Rint = 0.031

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.094

  • S = 1.04

  • 2685 reflections

  • 201 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯N5i 0.95 2.56 3.3483 (17) 140
N5—H5B⋯N2ii 0.91 2.31 3.1702 (15) 158
N5—H5A⋯N6 0.91 1.97 2.7111 (15) 138
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS, Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXT (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Pyrazine scaffold compounds are an interesting class of fused heterocyclic compounds due to their diverse properties in medicinal and applied chemistry. Pyrazolo[3,4-b]pyrazine derivatives have been reported to act as blood platelet aggregation inhibitors and bone metabolism improvers (El-Emary & El-Kashef, 2013). They also show antifungal and antiparasitic activities (El-Emary et al., 1998; El-Kashef et al., 2000; El-Emary, 2006). In addition, they are used as dye dispersants and as fluorescents (Rangnekar, 1990). In view of this medicinal importance, the crystal structure determination of the title compound was carried out and the results are presented here.

In the title compound, the pyrazolo[3,4-b]pyrazine core is planar (r.m.s. deviation 0.0089) with the phenyl ring inclined by 19.86 (5)° to it. An intramolecular N5—H5a···N6 hydrogen bond (Table 1 and Fig. 1) keeps the dihydroimidazolyl substituent nearly coplanar with the core. Intermolecular N5—H5b···N2 and C6—H6···N5 hydrogen bonds form chains of molecules (Table 1 and Fig. 2) which stack via ππ interactions between pyrazine rings (Cgi···Cgii = Cgiii··· Cgiv = 3.43 Å. Cgi: 0.5 - x, 1/2 + y, 0.5 - z; Cgii: -1/2 + x, 1/2 + y, z; Cgiii: 0.5 - x, -1/2 + y, 0.5 - z; Cgiv: -1/2 + x, -1/2 + y, z. Figs. 3 and 4). The chains run approximately parallel to (102).

Related literature top

For the synthesis of similar pyrazolo[3,4-b]pyrazines, see: El-Emary & El-Kashef (2013). For different biological and industrial applications of pyrazolopyrazine scaffold compounds, see: El-Emary et al. (1998); El-Kashef et al. (2000); El-Emary (2006); Rangnekar (1990).

Experimental top

The title compound has been prepared according to our reported method (El-Kashef et al., 2000). The product was crystallized from dioxan to furnish a good yield (68%) of colourles crystals (m.p. 503–505 K) which were of suffiecient quality for X-ray diffraction.

Refinement top

H-atoms attached to carbon were placed in calculated positions (C—H = 0.95 - 0.98 Å) while those attached to nitrogen were placed in locations derived from a difference map and their parameters adjusted to give N—H = 0.91 Å. All were included as riding contributions with isotropic displacement parameters 1.2 - 1.5 times those of the attached atoms.

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL2014 (Sheldrick, 2008).

Figures top
Figure 1. The title molecule with numbering scheme and 50% probability ellipsoids. The intramolecular hydrogen bond is shown as a blue dotted line.

Figure 2. Plan view of the chain showing N—H···N and C—H···N hydrogen bonds as blue and black dotted lines, respectively.

Figure 3. Elevation view of two chains showing the π-π interactions as green dotted lines.

Figure 4. Packing viewed down the a axis.
5-(4,5-Dihydro-1H-imidazol-2-yl)-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyrazin-6-amine top
Crystal data top
C15H15N7F(000) = 1232
Mr = 293.34Dx = 1.415 Mg m3
Monoclinic, C2/cCu Kα radiation, λ = 1.54178 Å
a = 7.9412 (2) ÅCell parameters from 9946 reflections
b = 15.7078 (3) Åθ = 4.0–71.7°
c = 22.3276 (4) ŵ = 0.75 mm1
β = 98.573 (1)°T = 150 K
V = 2754.00 (10) Å3Block, colourless
Z = 80.15 × 0.10 × 0.05 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
2685 independent reflections
Radiation source: INCOATEC IµS micro–focus source2335 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.031
Detector resolution: 10.4167 pixels mm-1θmax = 72.0°, θmin = 4.0°
ω scansh = 99
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
k = 1918
Tmin = 0.93, Tmax = 0.97l = 2527
21033 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.035H-atom parameters constrained
wR(F2) = 0.094 w = 1/[σ2(Fo2) + (0.047P)2 + 1.7272P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
2685 reflectionsΔρmax = 0.23 e Å3
201 parametersΔρmin = 0.17 e Å3
0 restraintsExtinction correction: SHELXL2014 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00012 (3)
Crystal data top
C15H15N7V = 2754.00 (10) Å3
Mr = 293.34Z = 8
Monoclinic, C2/cCu Kα radiation
a = 7.9412 (2) ŵ = 0.75 mm1
b = 15.7078 (3) ÅT = 150 K
c = 22.3276 (4) Å0.15 × 0.10 × 0.05 mm
β = 98.573 (1)°
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
2685 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
2335 reflections with I > 2σ(I)
Tmin = 0.93, Tmax = 0.97Rint = 0.031
21033 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.094H-atom parameters constrained
S = 1.04Δρmax = 0.23 e Å3
2685 reflectionsΔρmin = 0.17 e Å3
201 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. H-atoms attached to carbon were placed in calculated positions (C—H = 0.95 - 0.98 Å) while those attached to nitrogen were placed in locations derived from a difference map and their parameters adjusted to give N—H = 0.91 Å. All were included as riding contributions with isotropic displacement parameters 1.2 - 1.5 times those of the attached atoms.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.21440 (13)0.23938 (6)0.22995 (4)0.0252 (2)
N20.24278 (14)0.15429 (6)0.24683 (5)0.0284 (3)
N30.49830 (13)0.27132 (6)0.36366 (5)0.0255 (2)
N40.31514 (13)0.37679 (6)0.27055 (4)0.0258 (2)
N50.43603 (15)0.49390 (7)0.32160 (5)0.0350 (3)
H5A0.50510.51490.35450.042*
H5B0.38060.52950.29310.042*
N60.62895 (15)0.47203 (7)0.43134 (5)0.0345 (3)
N70.69317 (15)0.33776 (7)0.46313 (5)0.0339 (3)
H7A0.72650.28590.45110.041*
C10.10360 (15)0.25899 (8)0.17597 (5)0.0255 (3)
C20.03232 (16)0.33968 (8)0.16704 (6)0.0292 (3)
H20.06000.38290.19670.035*
C30.07919 (17)0.35656 (9)0.11468 (6)0.0325 (3)
H30.12690.41190.10830.039*
C40.12216 (18)0.29404 (9)0.07151 (6)0.0366 (3)
H40.20160.30570.03630.044*
C50.04798 (19)0.21408 (9)0.08019 (6)0.0382 (3)
H50.07570.17110.05040.046*
C60.06600 (18)0.19648 (8)0.13184 (6)0.0322 (3)
H60.11830.14210.13710.039*
C70.30685 (15)0.29182 (8)0.27108 (5)0.0241 (3)
C80.39641 (15)0.23910 (8)0.31557 (5)0.0251 (3)
C90.35066 (16)0.15415 (8)0.29763 (6)0.0278 (3)
C100.4086 (2)0.07325 (9)0.32887 (7)0.0377 (3)
H10A0.34650.02530.30790.057*
H10B0.38660.07530.37090.057*
H10C0.53090.06590.32840.057*
C110.41803 (16)0.40912 (8)0.31815 (5)0.0260 (3)
C120.50810 (15)0.35545 (8)0.36559 (5)0.0253 (3)
C130.61270 (16)0.39176 (8)0.41964 (5)0.0263 (3)
C140.80754 (19)0.38977 (9)0.50567 (6)0.0366 (3)
H14A0.92680.38540.49800.044*
H14B0.80180.37360.54820.044*
C150.73523 (19)0.47864 (9)0.49128 (6)0.0380 (3)
H15A0.66580.49700.52230.046*
H15B0.82830.52030.49010.046*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0278 (5)0.0214 (5)0.0242 (5)0.0011 (4)0.0036 (4)0.0001 (4)
N20.0326 (6)0.0213 (5)0.0288 (6)0.0016 (4)0.0037 (4)0.0005 (4)
N30.0263 (5)0.0237 (5)0.0250 (5)0.0011 (4)0.0008 (4)0.0008 (4)
N40.0269 (6)0.0230 (5)0.0256 (5)0.0006 (4)0.0019 (4)0.0005 (4)
N50.0429 (7)0.0222 (5)0.0345 (6)0.0006 (5)0.0123 (5)0.0005 (4)
N60.0385 (6)0.0279 (6)0.0329 (6)0.0012 (5)0.0082 (5)0.0059 (5)
N70.0434 (7)0.0270 (6)0.0269 (6)0.0027 (5)0.0087 (5)0.0004 (4)
C10.0244 (6)0.0276 (6)0.0233 (6)0.0040 (5)0.0007 (5)0.0017 (5)
C20.0300 (7)0.0289 (7)0.0269 (6)0.0004 (5)0.0014 (5)0.0016 (5)
C30.0319 (7)0.0319 (7)0.0315 (7)0.0023 (5)0.0024 (6)0.0031 (5)
C40.0370 (7)0.0396 (8)0.0289 (7)0.0038 (6)0.0095 (6)0.0032 (6)
C50.0465 (8)0.0337 (7)0.0301 (7)0.0065 (6)0.0088 (6)0.0033 (6)
C60.0387 (7)0.0251 (6)0.0300 (7)0.0030 (5)0.0035 (6)0.0002 (5)
C70.0232 (6)0.0249 (6)0.0233 (6)0.0013 (5)0.0009 (5)0.0011 (5)
C80.0260 (6)0.0233 (6)0.0245 (6)0.0000 (5)0.0010 (5)0.0002 (5)
C90.0300 (7)0.0246 (6)0.0270 (6)0.0013 (5)0.0018 (5)0.0002 (5)
C100.0463 (8)0.0254 (7)0.0364 (7)0.0021 (6)0.0108 (6)0.0029 (5)
C110.0261 (6)0.0244 (6)0.0262 (6)0.0006 (5)0.0004 (5)0.0016 (5)
C120.0251 (6)0.0243 (6)0.0253 (6)0.0011 (5)0.0005 (5)0.0016 (5)
C130.0259 (6)0.0268 (6)0.0252 (6)0.0011 (5)0.0007 (5)0.0008 (5)
C140.0408 (8)0.0371 (7)0.0280 (7)0.0054 (6)0.0075 (6)0.0028 (6)
C150.0398 (8)0.0359 (7)0.0339 (7)0.0033 (6)0.0089 (6)0.0089 (6)
Geometric parameters (Å, º) top
N1—C71.3638 (15)C3—C41.3826 (19)
N1—N21.3978 (14)C3—H30.9500
N1—C11.4161 (16)C4—C51.389 (2)
N2—C91.3158 (17)C4—H40.9500
N3—C121.3241 (16)C5—C61.3836 (19)
N3—C81.3435 (16)C5—H50.9500
N4—C71.3365 (16)C6—H60.9500
N4—C111.3401 (16)C7—C81.4028 (17)
N5—C111.3404 (16)C8—C91.4246 (17)
N5—H5A0.9100C9—C101.4891 (18)
N5—H5B0.9099C10—H10A0.9800
N6—C131.2902 (17)C10—H10B0.9800
N6—C151.4755 (17)C10—H10C0.9800
N7—C131.3732 (16)C11—C121.4554 (17)
N7—C141.4620 (17)C12—C131.4741 (16)
N7—H7A0.9099C14—C151.525 (2)
C1—C21.3904 (18)C14—H14A0.9900
C1—C61.3916 (18)C14—H14B0.9900
C2—C31.3829 (18)C15—H15A0.9900
C2—H20.9500C15—H15B0.9900
C7—N1—N2110.30 (10)N3—C8—C7121.67 (11)
C7—N1—C1130.20 (10)N3—C8—C9132.50 (11)
N2—N1—C1119.48 (10)C7—C8—C9105.83 (11)
C9—N2—N1106.98 (10)N2—C9—C8110.29 (11)
C12—N3—C8115.30 (10)N2—C9—C10121.41 (11)
C7—N4—C11113.36 (10)C8—C9—C10128.29 (11)
C11—N5—H5A116.9C9—C10—H10A109.5
C11—N5—H5B122.3C9—C10—H10B109.5
H5A—N5—H5B120.8H10A—C10—H10B109.5
C13—N6—C15106.19 (11)C9—C10—H10C109.5
C13—N7—C14107.03 (11)H10A—C10—H10C109.5
C13—N7—H7A118.0H10B—C10—H10C109.5
C14—N7—H7A120.9N4—C11—N5117.98 (11)
C2—C1—C6120.12 (12)N4—C11—C12122.21 (11)
C2—C1—N1120.56 (11)N5—C11—C12119.81 (11)
C6—C1—N1119.31 (11)N3—C12—C11122.30 (11)
C3—C2—C1119.46 (12)N3—C12—C13115.85 (11)
C3—C2—H2120.3C11—C12—C13121.83 (11)
C1—C2—H2120.3N6—C13—N7116.00 (11)
C4—C3—C2120.89 (13)N6—C13—C12124.83 (11)
C4—C3—H3119.6N7—C13—C12119.08 (11)
C2—C3—H3119.6N7—C14—C15101.34 (10)
C3—C4—C5119.33 (12)N7—C14—H14A111.5
C3—C4—H4120.3C15—C14—H14A111.5
C5—C4—H4120.3N7—C14—H14B111.5
C6—C5—C4120.54 (13)C15—C14—H14B111.5
C6—C5—H5119.7H14A—C14—H14B109.3
C4—C5—H5119.7N6—C15—C14105.85 (10)
C5—C6—C1119.60 (13)N6—C15—H15A110.6
C5—C6—H6120.2C14—C15—H15A110.6
C1—C6—H6120.2N6—C15—H15B110.6
N4—C7—N1128.29 (11)C14—C15—H15B110.6
N4—C7—C8125.12 (11)H15A—C15—H15B108.7
N1—C7—C8106.59 (10)
C7—N1—N2—C90.15 (14)N1—N2—C9—C80.06 (15)
C1—N1—N2—C9179.34 (11)N1—N2—C9—C10179.61 (12)
C7—N1—C1—C220.6 (2)N3—C8—C9—N2178.77 (13)
N2—N1—C1—C2160.36 (11)C7—C8—C9—N20.05 (15)
C7—N1—C1—C6159.58 (12)N3—C8—C9—C100.9 (2)
N2—N1—C1—C619.42 (17)C7—C8—C9—C10179.69 (14)
C6—C1—C2—C31.55 (19)C7—N4—C11—N5179.53 (11)
N1—C1—C2—C3178.23 (11)C7—N4—C11—C120.94 (17)
C1—C2—C3—C40.8 (2)C8—N3—C12—C111.44 (17)
C2—C3—C4—C52.0 (2)C8—N3—C12—C13177.08 (10)
C3—C4—C5—C60.9 (2)N4—C11—C12—N32.23 (19)
C4—C5—C6—C11.4 (2)N5—C11—C12—N3178.24 (12)
C2—C1—C6—C52.6 (2)N4—C11—C12—C13176.20 (11)
N1—C1—C6—C5177.17 (12)N5—C11—C12—C133.32 (18)
C11—N4—C7—N1179.70 (12)C15—N6—C13—N70.00 (16)
C11—N4—C7—C80.87 (18)C15—N6—C13—C12176.46 (12)
N2—N1—C7—N4179.34 (12)C14—N7—C13—N612.26 (16)
C1—N1—C7—N40.3 (2)C14—N7—C13—C12171.07 (11)
N2—N1—C7—C80.18 (13)N3—C12—C13—N6175.55 (12)
C1—N1—C7—C8179.25 (12)C11—C12—C13—N63.0 (2)
C12—N3—C8—C70.33 (17)N3—C12—C13—N70.80 (17)
C12—N3—C8—C9178.99 (13)C11—C12—C13—N7179.33 (11)
N4—C7—C8—N31.63 (19)C13—N7—C14—C1517.78 (15)
N1—C7—C8—N3178.84 (11)C13—N6—C15—C1411.67 (16)
N4—C7—C8—C9179.40 (12)N7—C14—C15—N617.76 (15)
N1—C7—C8—C90.14 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···N5i0.952.563.3483 (17)140
N5—H5B···N2ii0.912.313.1702 (15)158
N5—H5A···N60.911.972.7111 (15)138
Symmetry codes: (i) x+1/2, y1/2, z+1/2; (ii) x+1/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···N5i0.952.563.3483 (17)140
N5—H5B···N2ii0.912.313.1702 (15)158
N5—H5A···N60.911.972.7111 (15)138
Symmetry codes: (i) x+1/2, y1/2, z+1/2; (ii) x+1/2, y+1/2, z+1/2.
 

Acknowledgements

The support of NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged. In addition, TIE would like to express his thanks to Professor H. M. S. El-Kashef, Assiut University, for his contribution to this study.

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Volume 70| Part 11| November 2014| Pages o1212-o1213
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