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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 6| June 2014| Pages o629-o630

(5E)-1-Benzyl-5-(3,3,3-tri­chloro-2-oxo­propyl­­idene)pyrrolidin-2-one

aEscola de Química e Alimentos, Universidade Federal do Rio Grande, Av. Itália, km 08, Campus Carreiros, 96203-900, Rio Grande, RS, Brazil, bUniversidade Federal da Grande Dourados, UFGD, CEP 79825-070, Dourados, MS, Brazil, and cInstituto Federal Farroupilha, Campus Júlio de Castilhos, CEP 98130-000, Júlio de Castilhos, RS, Brazil
*Correspondence e-mail: alexflores@furg.br

(Received 14 March 2014; accepted 3 April 2014; online 3 May 2014)

In the crystal structure of the title compound, C14H12Cl3NO2, no classical hydrogen-bonding inter­actions are observed. The methyl­ene fragments of the benzyl groups participate in non-classic hydrogen-bond inter­actions with the carbonyl O atoms of neighboring mol­ecules, generating co-operative centrosymmetric dimers with R55(10) ring motifs. The overall mol­ecular arrangement in the unit cell seems to be highly influenced by secondary non-covalent weak C—Cl⋯π [Cl⋯Cg(phenyl ring) = 3.732 (2) Å] and C—O⋯π [O⋯Cg(pyrrolidine ring) = 2.985 (2) Å] contacts.

Related literature

For the synthesis of the title compound, see: Flores et al. (2008[Flores, A. F. C., Flores, D. C., Oliveira, G., Pizzuti, L., Silva, R. M. S., Martins, M. A. P. & Bonacorso, H. G. (2008). J. Braz. Chem. Soc. 19, 184-193.]). For pharmacological effects, see: Van der Schyf et al. (2006[Van der Schyf, C., Geldenhuys, W. J. & Youdim, M. B. H. (2006). J. Neurochem. 99, 1033-1048.]). For non-classical weak contacts, see: Irving & Irving (1994[Irving, A. & Irving, H. M. N. H. (1994). J. Chem. Crystallogr. 24, 251-257.]); Bissantz et al. (2010[Bissantz, C., Kuhn, B. & Stahl, M. (2010). J. Med. Chem. 53, 5061-5084.]). For related structures, see: Bandeira et al. (2013[Bandeira, K. C. T., Bresolin, L., Näther, C., Jess, I. & Oliveira, A. B. (2013). Acta Cryst. E69, o1251-o1252.]); de Oliveira et al. (2012[Oliveira, A. B. de, Silva, C. S., Feitosa, B. R. S., Näther, C. & Jess, I. (2012). Acta Cryst. E68, o2581.]); de Bittencourt et al. (2014[Bittencourt, V. C. D. de, Vicenti, J. R. de M., Velasques, J. M., Zambiazi, P. J. & Gervini, V. C. (2014). Acta Cryst. E70, o64-o65.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12Cl3NO2

  • Mr = 332.60

  • Monoclinic, P 21 /n

  • a = 15.7822 (5) Å

  • b = 5.8465 (2) Å

  • c = 17.4107 (5) Å

  • β = 105.885 (1)°

  • V = 1545.15 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.59 mm−1

  • T = 293 K

  • 0.83 × 0.23 × 0.19 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: gaussian (XPREP; Bruker, 2009[Bruker (2009). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.814, Tmax = 1.000

  • 21458 measured reflections

  • 5069 independent reflections

  • 2436 reflections with I > 2σ(I)

  • Rint = 0.033

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.217

  • S = 1.00

  • 5069 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.51 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H82⋯O71i 0.97 2.38 3.292 (3) 156
Symmetry code: (i) -x+1, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and XPREP. 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: DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Pyrrolidin-2-ones have received considerable attention due to their activity in CNS as nootropic drugs. Piracetam-like nootropics revert amnesia induced by scopolamine and other amnesing drugs, electroconvulsive shock and hypoxia with an unknown mechanism. In general, they show no affinity for the most important central receptors, but are able to modulate the action of these most important central neurotransmitters, in particular acetylcholine and glutamate. Extensive study of the modes of action of the 2-pyrrolidinones has revealed various pharmacological effects, with striking differences between drugs (Van der Schyf et al., 2006). This work is a continuation of the research on the synthesis of 1-[alkyl(aryl)]-5-(3,3,3-trihalo-2-oxopropylidene)pyrrolidin-2-nes (Flores et al., 2008). In the crystal structure of the title compound, C14H12O2NCl3 (Fig. 1), no classic hydrogen bonds are observed. There is a non-classic intramolecular hydrogen bond with a distance C8—H82···O71 of 2.442 Å, generating a S(5) ring motif (de Bittencourt et al., 2014). The molecule possesses two sites revealing an interesting geometric conformation: the plane defined by the aromatic ring (r.m.s. of 0.0032 Å) revealed a dihedral angle of 87.03 (8)° with respect to the second plane formed by C1/C2/O21/C3/C4/C5/C6/C7/N1/C8/O71 atoms (r.m.s. of 0.0978 Å; Bandeira et al., 2013; de Oliveira et al., 2012). This almost orthogonal configuration (Fig. 2) seems to be related with the crystal packing. In this context, the CH2 fragment of the benzyl group participates in non-classic hydrogen bonding with carbonyl oxygen of the neighbor molecules. This feature generates co-operative centrosymmetric dimers related through inversion centers, displaying C8ii—H82ii···O71i distances of 2.382 Å in a R55(10) ring fashion (de Bittencourt et al., 2014). The overall molecular arrangement in the unit cell (Fig. 3) seems to be highly influenced by weak interactions, where O21iii are clearly pointing to C(1) (2.985 Å), related to the centroid of the neighbor ring formed by C4ii/C5ii/C6ii/C7ii/N1ii atoms. Similarly, the centroid C(2) of the ring formed by C9iv/C10iv/C11iv/C12iv/C13iv/C14iv atoms from the benzyl fragment presented directional long range interactions with adjacent Cl11ii atoms (Irving & Irving, 1994; Bissantz et al., 2010), with distances of 3.732 Å (symmetry codes: (i) –x + 3/2, y + 1/2, –z + 3/2; (ii) x + 1/2, –y + 3/2, z–1/2; (iii) –x + 1, –y + 1, –z + 1; (iv) x, y + 1, z–1).

Related literature top

For the synthesis of the title compound, see: Flores et al. (2008). For pharmacological effects, see: Van der Schyf et al. (2006). For non-classical weak contacts, see: Irving & Irving (1994); Bissantz et al. (2010). For related structures, see: Bandeira et al. (2013); de Oliveira et al. (2012); de Bittencourt et al. (2014).

Experimental top

To a stirred solution of methyl 7,7,7-trichloro-4-methoxy-6-oxo-3-heptenoate (5 mmol, 1.52 g) in CHCl3 (5 ml) kept at 25 °C, was added benzylamine (Aldrich, 185701, 5.1 mmol, 0.58 ml) in CHCl3 (5 ml). The mixture was stirred at 25 °C for 2 h. Then the solvent was evaporated and residue was dried under vacuum. The brown amorphous solid was recrystallized in hexane to furnish yellowish needles with 94% yield. M.p. 88 - 89°C. 1H NMR (400 MHz, CDCl3/TMS): δ 2.72 (m, 2H, H3), 3.34 (m, 2H, H4), 4.8 (s, 2H, H9), 6.2 (s, 1H, H6), 7.3 (m, 5H, Ph) p.p.m. 13C NMR (100 MHz, CDCl3): 26.1, 27.5, 44.6, 91.7, 97.1, 127.6, 128.1, 128.9, 134.1, 166.4, 177.1, 180 p.p.m. Crystals were grown from a diluted hexane solution at room temperature.

Refinement top

All H atoms attached to C atoms were positioned with idealized geometry and were refined isotropic with Ueq(H) set to 1.2 times of the Ueq(C). It was used a riding model with C—H = 0.97 Å for CH2 and C—H = 0.93 Å for CH. Reflection (101) was omitted due to the large difference observed between Fo2 and Fc2. The crystals were relatively weak in terms of intensity of diffraction, prompting us to select a big crystal for the measurement and consequently a collimator with a larger diameter (0.6 mm) than in routine studies.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Asymmetric unit of the title compound showing an intramolecular hydrogen bond interaction represented with red dashed lines. Ellipsoid probability: 50%.
[Figure 2] Fig. 2. Representation of the two mean planes traced through non-hydrogenoid atoms considered for dihedral angle calculation.
[Figure 3] Fig. 3. Packing diagram showing the molecular arrangement in the unit cell. Non-classic hydrogen bond interactions are represented with red dashed lines, meanwhile other weak non-covalent contacts are represented with orange and green dashed lines. Most of the hydrogen atoms were omitted for clarity. Symmetry codes: (i) –x + 3/2, y + 1/2, –z + 3/2; (ii) x + 1/2, –y + 3/2, z–1/2; (iii) –x + 1, –y + 1, –z + 1; (iv) x, y + 1, z–1.
(E)-1-Benzyl-5-(3,3,3-trichloro-2-oxopropylidene)pyrrolidin-2-one top
Crystal data top
C14H12Cl3NO2F(000) = 680
Mr = 332.60Dx = 1.430 Mg m3
Monoclinic, P21/nMelting point: 361 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 15.7822 (5) ÅCell parameters from 3113 reflections
b = 5.8465 (2) Åθ = 2.4–21.5°
c = 17.4107 (5) ŵ = 0.59 mm1
β = 105.885 (1)°T = 293 K
V = 1545.15 (8) Å3Block, yellow
Z = 40.83 × 0.23 × 0.19 mm
Data collection top
Bruker APEXII CCD
diffractometer
5069 independent reflections
Radiation source: fine-focus sealed tube2436 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ϕ and ω scansθmax = 31.5°, θmin = 2.7°
Absorption correction: gaussian
(XPREP; Bruker, 2009)
h = 2323
Tmin = 0.814, Tmax = 1k = 83
21458 measured reflectionsl = 2525
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)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.217H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.1095P)2 + 0.2217P]
where P = (Fo2 + 2Fc2)/3
5069 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = 0.51 e Å3
Crystal data top
C14H12Cl3NO2V = 1545.15 (8) Å3
Mr = 332.60Z = 4
Monoclinic, P21/nMo Kα radiation
a = 15.7822 (5) ŵ = 0.59 mm1
b = 5.8465 (2) ÅT = 293 K
c = 17.4107 (5) Å0.83 × 0.23 × 0.19 mm
β = 105.885 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
5069 independent reflections
Absorption correction: gaussian
(XPREP; Bruker, 2009)
2436 reflections with I > 2σ(I)
Tmin = 0.814, Tmax = 1Rint = 0.033
21458 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0540 restraints
wR(F2) = 0.217H-atom parameters constrained
S = 1.00Δρmax = 0.43 e Å3
5069 reflectionsΔρmin = 0.51 e Å3
181 parameters
Special details top

Experimental. Gaussian absorption correction based on the face-indexed crystal size

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
Cl110.04344 (5)0.0759 (2)0.73859 (6)0.0958 (3)
Cl120.01375 (6)0.32178 (15)0.83385 (6)0.0921 (3)
Cl130.03185 (7)0.11995 (17)0.90926 (6)0.0955 (3)
O710.50426 (12)0.2290 (4)0.95046 (11)0.0688 (5)
N10.35352 (12)0.2022 (3)0.92101 (10)0.0485 (5)
O210.13827 (13)0.1294 (4)0.75824 (13)0.0766 (6)
C90.30299 (15)0.3271 (4)1.03807 (14)0.0517 (6)
C40.28593 (15)0.0825 (4)0.87105 (13)0.0473 (5)
C20.13065 (16)0.0046 (4)0.81150 (14)0.0541 (6)
C30.20017 (17)0.1159 (4)0.86770 (14)0.0537 (6)
H30.18580.21950.90270.064*
C80.34165 (19)0.3933 (4)0.97121 (15)0.0573 (6)
H810.30350.50580.93790.069*
H820.39840.46530.99390.069*
C60.42339 (17)0.0584 (5)0.85719 (15)0.0584 (6)
H620.44890.19740.88430.070*
H610.45070.02630.81480.070*
C50.32443 (16)0.0833 (4)0.82383 (14)0.0507 (5)
H510.30620.04550.76740.061*
H520.30600.23840.83080.061*
C100.32564 (18)0.1269 (5)1.08009 (16)0.0614 (7)
H100.36540.02751.06670.074*
C70.43644 (17)0.1369 (4)0.91455 (14)0.0536 (6)
C110.2900 (2)0.0712 (7)1.14227 (18)0.0810 (9)
H110.30590.06531.16990.097*
C140.2441 (2)0.4725 (6)1.0591 (2)0.0778 (8)
H140.22730.60871.03150.093*
C130.2094 (2)0.4110 (8)1.1238 (2)0.0972 (12)
H130.17040.50881.13890.117*
C10.03650 (17)0.0294 (5)0.82250 (16)0.0615 (6)
C120.2326 (2)0.2126 (8)1.1629 (2)0.0930 (11)
H120.20890.17291.20440.112*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl110.0520 (4)0.1369 (8)0.0932 (6)0.0116 (4)0.0110 (4)0.0291 (5)
Cl120.0838 (6)0.0785 (6)0.1221 (7)0.0163 (4)0.0416 (5)0.0080 (5)
Cl130.0997 (7)0.1099 (7)0.0892 (6)0.0161 (5)0.0465 (5)0.0130 (5)
O710.0531 (10)0.0804 (13)0.0728 (11)0.0168 (9)0.0169 (9)0.0078 (10)
N10.0497 (10)0.0571 (11)0.0417 (9)0.0128 (8)0.0175 (8)0.0064 (8)
O210.0558 (11)0.0922 (15)0.0809 (13)0.0063 (10)0.0169 (10)0.0388 (11)
C90.0454 (12)0.0599 (14)0.0497 (12)0.0087 (10)0.0130 (10)0.0156 (11)
C40.0522 (13)0.0517 (12)0.0396 (11)0.0085 (10)0.0155 (9)0.0008 (9)
C20.0508 (13)0.0580 (14)0.0547 (14)0.0029 (11)0.0166 (11)0.0057 (11)
C30.0545 (13)0.0597 (14)0.0491 (13)0.0055 (11)0.0176 (11)0.0090 (10)
C80.0633 (15)0.0533 (13)0.0576 (14)0.0138 (11)0.0205 (12)0.0080 (11)
C60.0532 (14)0.0696 (16)0.0537 (14)0.0010 (11)0.0167 (11)0.0030 (12)
C50.0551 (13)0.0542 (13)0.0441 (11)0.0039 (10)0.0158 (10)0.0027 (10)
C100.0568 (15)0.0748 (17)0.0579 (14)0.0009 (12)0.0245 (12)0.0040 (13)
C70.0545 (14)0.0640 (14)0.0433 (12)0.0096 (11)0.0150 (10)0.0011 (10)
C110.088 (2)0.101 (2)0.0599 (17)0.0077 (18)0.0312 (16)0.0037 (16)
C140.0735 (19)0.081 (2)0.082 (2)0.0109 (15)0.0257 (16)0.0153 (16)
C130.075 (2)0.140 (4)0.089 (2)0.013 (2)0.0438 (19)0.033 (2)
C10.0522 (14)0.0691 (16)0.0661 (16)0.0036 (12)0.0208 (12)0.0052 (13)
C120.088 (2)0.131 (3)0.074 (2)0.013 (2)0.0459 (19)0.012 (2)
Geometric parameters (Å, º) top
Cl11—C11.760 (3)C8—H820.9700
Cl12—C11.769 (3)C6—C71.494 (3)
Cl13—C11.764 (3)C6—C51.517 (4)
O71—C71.208 (3)C6—H620.9700
N1—C41.370 (3)C6—H610.9700
N1—C71.397 (3)C5—H510.9700
N1—C81.462 (3)C5—H520.9700
O21—C21.212 (3)C10—C111.389 (4)
C9—C101.375 (4)C10—H100.9300
C9—C141.381 (4)C11—C121.345 (5)
C9—C81.505 (3)C11—H110.9300
C4—C31.353 (3)C14—C131.426 (5)
C4—C51.503 (3)C14—H140.9300
C2—C31.439 (4)C13—C121.345 (6)
C2—C11.562 (3)C13—H130.9300
C3—H30.9300C12—H120.9300
C8—H810.9700
C4—N1—C7113.14 (19)C6—C5—H51110.8
C4—N1—C8124.4 (2)C4—C5—H52110.8
C7—N1—C8122.2 (2)C6—C5—H52110.8
C10—C9—C14118.6 (2)H51—C5—H52108.8
C10—C9—C8121.9 (2)C9—C10—C11120.8 (3)
C14—C9—C8119.4 (3)C9—C10—H10119.6
C3—C4—N1123.4 (2)C11—C10—H10119.6
C3—C4—C5128.2 (2)O71—C7—N1123.6 (2)
N1—C4—C5108.4 (2)O71—C7—C6128.8 (2)
O21—C2—C3126.8 (2)N1—C7—C6107.6 (2)
O21—C2—C1117.9 (2)C12—C11—C10120.7 (4)
C3—C2—C1115.4 (2)C12—C11—H11119.7
C4—C3—C2121.8 (2)C10—C11—H11119.7
C4—C3—H3119.1C9—C14—C13119.1 (3)
C2—C3—H3119.1C9—C14—H14120.5
N1—C8—C9114.3 (2)C13—C14—H14120.5
N1—C8—H81108.7C12—C13—C14120.5 (3)
C9—C8—H81108.7C12—C13—H13119.8
N1—C8—H82108.7C14—C13—H13119.8
C9—C8—H82108.7C2—C1—Cl11110.10 (18)
H81—C8—H82107.6C2—C1—Cl13107.82 (19)
C7—C6—C5105.6 (2)Cl11—C1—Cl13110.45 (15)
C7—C6—H62110.6C2—C1—Cl12111.45 (18)
C5—C6—H62110.6Cl11—C1—Cl12108.04 (16)
C7—C6—H61110.6Cl13—C1—Cl12109.00 (15)
C5—C6—H61110.6C13—C12—C11120.3 (3)
H62—C6—H61108.8C13—C12—H12119.8
C4—C5—C6104.88 (19)C11—C12—H12119.8
C4—C5—H51110.8
C7—N1—C4—C3179.4 (2)C8—N1—C7—O711.3 (4)
C8—N1—C4—C35.8 (3)C4—N1—C7—C63.7 (3)
C7—N1—C4—C50.5 (3)C8—N1—C7—C6178.6 (2)
C8—N1—C4—C5174.3 (2)C5—C6—C7—O71173.7 (3)
N1—C4—C3—C2176.7 (2)C5—C6—C7—N16.2 (3)
C5—C4—C3—C23.4 (4)C9—C10—C11—C120.2 (5)
O21—C2—C3—C46.5 (4)C10—C9—C14—C130.4 (4)
C1—C2—C3—C4172.5 (2)C8—C9—C14—C13178.5 (3)
C4—N1—C8—C967.9 (3)C9—C14—C13—C121.0 (6)
C7—N1—C8—C9117.8 (2)O21—C2—C1—Cl1113.2 (3)
C10—C9—C8—N138.3 (3)C3—C2—C1—Cl11167.62 (19)
C14—C9—C8—N1142.8 (3)O21—C2—C1—Cl13107.3 (3)
C3—C4—C5—C6175.6 (2)C3—C2—C1—Cl1371.8 (3)
N1—C4—C5—C64.3 (2)O21—C2—C1—Cl12133.1 (2)
C7—C6—C5—C46.3 (2)C3—C2—C1—Cl1247.8 (3)
C14—C9—C10—C110.2 (4)C14—C13—C12—C111.0 (6)
C8—C9—C10—C11179.1 (3)C10—C11—C12—C130.4 (6)
C4—N1—C7—O71176.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H82···O71i0.972.383.292 (3)156
Symmetry code: (i) x+1, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H82···O71i0.972.383.292 (3)156
Symmetry code: (i) x+1, y+1, z+2.
 

Acknowledgements

The authors acknowledge the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Universal grant 6577818477962764–01), the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES-PROEX) and the Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS, PqG grant 1016236) for financial support.

References

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Volume 70| Part 6| June 2014| Pages o629-o630
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