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

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ISSN: 2056-9890

2-Chloro-N-[(4-chloro­phen­yl)(phen­yl)meth­yl]-N-[2-(4-nitro-1H-imidazol-1-yl)eth­yl]ethanamine

aLaboratory of Bioorganic & Medicinal Chemistry, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, People's Republic of China
*Correspondence e-mail: zhouch@swu.edu.cn

(Received 18 January 2011; accepted 19 January 2011; online 26 January 2011)

In the title compound, C20H20Cl2N4O2, the nitro­imidazole ring makes dihedral angles of 17.00 (1) and 60.45 (11)° with the phenyl and chloro­phenyl rings, respectively. The three-coordinate N atom connected to two methyl­ene and one methine C atoms shows pyramidal coordination.

Related literature

For the use of nitro­gen mustards containing the β-chloro­ethyl­amine unit as anti­tumor drugs, see: Zhuang et al. (2008[Zhuang, Y. Y., Zhou, C. H., Wang, Y. F. & Li, D. H. (2008). Chin. Pharm. J. 43, 1281-1287.]). Nitro­imidazole compounds are also used extensively in the treatment of various cancers as clinical radiosensitizers, see: Cai et al. (2009[Cai, J. L., Li, S., Zhou, C. H., Gan, L. L. & Wu, J. (2009). Chin. J. New Drugs, 18, 598-652.]). For the synthesis, see: Fang et al. (2010[Fang, B., Zhou, C. H. & Rao, X. C. (2010). Eur. J. Med. Chem. 45, 4388-4398.]); Gan et al. (2010[Gan, L. L., Fang, B. & Zhou, C. H. (2010). Bull. Kor. Chem. Soc. 31, 3684-3693.]).

[Scheme 1]

Experimental

Crystal data
  • C20H20Cl2N4O2

  • Mr = 419.30

  • Monoclinic, P 21 /n

  • a = 8.8206 (16) Å

  • b = 25.005 (5) Å

  • c = 9.0450 (17) Å

  • β = 100.802 (3)°

  • V = 1959.6 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.36 mm−1

  • T = 298 K

  • 0.32 × 0.24 × 0.18 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.903, Tmax = 0.938

  • 9838 measured reflections

  • 3449 independent reflections

  • 2464 reflections with I > 2σ(I)

  • Rint = 0.037

Refinement
  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.139

  • S = 1.03

  • 3449 reflections

  • 253 parameters

  • H-atom parameters constrained

  • Δρmax = 0.49 e Å−3

  • Δρmin = −0.24 e Å−3

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SMART 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Nitrogen mustards as anticancer agents containing typical β-chloroethylamine moiety with easy synthesis and inexpensive expense are one of the most important antitumor drugs (Zhuang et al., 2008). Nitroimidazole compounds are also extensively used in the treatment of various cancers as clinical radiosensitizer (Cai et al., 2009). In view of this, it is of great interest for us to investigate the nitrogen mustard-based nitroimidazoles as new potential anticancer agents. Herein we would like to report the crystal structure of the title compound (I).

The title compound, C20H20Cl2N4O2, crystallized in non-chiral monoclinic crystal system of P2(1)/n space group, including a racemic chiral isomers. In the molecule, the nitroimidazole ring makes dihedral angles of 17.00 (1) and 60.45 (11)°, respectively, with the benzene and chlorophenyl ring.

Related literature top

For the use of nitrogen mustards containing a β-chloroethylamine moiety as antitumor drugs, see: Zhuang et al. (2008). Nitroimidazole compounds are also used extensively in the treatment of various cancers as clinical radiosensitizers, see: Cai et al. (2009). For the synthesis, see: Fang et al. (2010); Gan et al. (2010).

Experimental top

The intermediate 2-chloro-N-(2-chloroethyl)-N-((4-chlorophenyl(phenyl)methyl)ethanamine (0.85 g, 2.5 mmol), which was prepared according to the procedure of Fang et al.(2010) and Gan et al.(2010), reacted with 4-nitroimidazole (0.34 g, 3.0 mmol) in the presence of weak base in acetonitrile at 60 °C for 12 h to produce the title compound (I) 0.30 g as white solid via silica gel column chromatography (ethyl acetate/petroleum ether, 1/2, V/V). A crystal of (I) suitable for X-ray analysis was grown from a mixture solution of ethyl acetate and petroleum ether by slow evaporation at room temperature.

Refinement top

Hydrogen atoms were placed in idealized positions and treated as riding, with C—H = 0.93Å (CH), 0.98Å (CH) or 0.98Å (CH2) and Uiso(H) = 1.2 Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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
[Figure 1] Fig. 1. Ellipsoid plot.
2-Chloro-N-[(4-chlorophenyl)(phenyl)methyl]-N-[2-(4-nitro- 1H-imidazol-1-yl)ethyl]ethanamine top
Crystal data top
C20H20Cl2N4O2Z = 4
Mr = 419.30F(000) = 872
Monoclinic, P21/nDx = 1.421 Mg m3
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.8206 (16) Åθ = 2.4–21.3°
b = 25.005 (5) ŵ = 0.36 mm1
c = 9.0450 (17) ÅT = 298 K
β = 100.802 (3)°Block, colourless
V = 1959.6 (6) Å30.32 × 0.24 × 0.18 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
3449 independent reflections
Radiation source: fine-focus sealed tube2464 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
phi and ω scansθmax = 25.0°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 107
Tmin = 0.903, Tmax = 0.938k = 2929
9838 measured reflectionsl = 1010
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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.139H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0576P)2 + 0.904P]
where P = (Fo2 + 2Fc2)/3
3449 reflections(Δ/σ)max = 0.001
253 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = 0.24 e Å3
Crystal data top
C20H20Cl2N4O2V = 1959.6 (6) Å3
Mr = 419.30Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.8206 (16) ŵ = 0.36 mm1
b = 25.005 (5) ÅT = 298 K
c = 9.0450 (17) Å0.32 × 0.24 × 0.18 mm
β = 100.802 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
3449 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2464 reflections with I > 2σ(I)
Tmin = 0.903, Tmax = 0.938Rint = 0.037
9838 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0530 restraints
wR(F2) = 0.139H-atom parameters constrained
S = 1.03Δρmax = 0.49 e Å3
3449 reflectionsΔρmin = 0.24 e Å3
253 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
C10.3270 (3)0.05952 (13)0.0927 (3)0.0487 (7)
C20.4173 (4)0.01834 (13)0.1569 (4)0.0615 (9)
H20.39720.01650.12310.074*
C30.5385 (4)0.02915 (12)0.2723 (3)0.0538 (8)
H30.59940.00090.31610.065*
C40.5734 (3)0.07989 (11)0.3257 (3)0.0402 (6)
C50.4771 (3)0.12070 (12)0.2588 (3)0.0498 (7)
H50.49570.15560.29330.060*
C60.3544 (3)0.11081 (12)0.1423 (3)0.0514 (8)
H60.29170.13860.09850.062*
C70.7143 (3)0.08861 (11)0.4496 (3)0.0401 (6)
H70.76280.05330.46540.048*
C80.6827 (3)0.10452 (10)0.6032 (3)0.0400 (6)
C90.8038 (3)0.10174 (11)0.7245 (3)0.0456 (7)
H90.89990.09020.70910.055*
C100.7859 (4)0.11550 (12)0.8666 (3)0.0536 (8)
H100.86950.11370.94630.064*
C110.6439 (4)0.13203 (13)0.8913 (4)0.0592 (8)
H110.63130.14170.98750.071*
C120.5226 (4)0.13412 (14)0.7746 (4)0.0657 (9)
H120.42630.14480.79120.079*
C130.5415 (3)0.12044 (12)0.6309 (3)0.0538 (8)
H130.45730.12200.55180.065*
C140.9049 (3)0.10277 (13)0.2887 (3)0.0547 (8)
H14A0.96710.13080.25590.066*
H14B0.82310.09410.20460.066*
C151.0037 (4)0.05433 (13)0.3272 (4)0.0591 (8)
H15A1.04570.04360.24000.071*
H15B0.94070.02520.35260.071*
C160.7954 (3)0.18032 (11)0.3913 (3)0.0498 (7)
H16A0.71320.18840.44560.060*
H16B0.75740.18760.28550.060*
C170.9333 (4)0.21643 (13)0.4485 (3)0.0557 (8)
H17A1.02050.20490.40510.067*
H17B0.90810.25280.41580.067*
C181.1030 (3)0.19238 (12)0.6938 (4)0.0523 (8)
H181.17750.17480.65160.063*
C190.9802 (3)0.22472 (11)0.8478 (3)0.0479 (7)
C200.8953 (3)0.23602 (11)0.7104 (4)0.0521 (8)
H200.80170.25420.68910.063*
Cl10.17478 (11)0.04618 (4)0.05458 (11)0.0835 (3)
Cl21.15787 (10)0.06636 (4)0.48090 (12)0.0777 (3)
N10.8356 (2)0.12352 (9)0.4102 (2)0.0412 (5)
N20.9760 (3)0.21524 (9)0.6115 (3)0.0458 (6)
N31.1106 (3)0.19743 (10)0.8388 (3)0.0538 (6)
N40.9403 (4)0.23746 (13)0.9901 (4)0.0692 (8)
O11.0250 (3)0.22177 (12)1.1050 (3)0.0897 (9)
O20.8228 (4)0.26290 (15)0.9864 (4)0.1142 (12)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0397 (16)0.0603 (19)0.0430 (17)0.0055 (14)0.0002 (13)0.0095 (14)
C20.059 (2)0.0473 (18)0.073 (2)0.0065 (16)0.0015 (18)0.0138 (16)
C30.0534 (18)0.0446 (17)0.060 (2)0.0017 (14)0.0013 (16)0.0014 (14)
C40.0360 (14)0.0425 (15)0.0416 (16)0.0020 (12)0.0059 (12)0.0013 (12)
C50.0451 (16)0.0416 (16)0.0565 (19)0.0023 (13)0.0061 (14)0.0055 (14)
C60.0427 (17)0.0503 (18)0.0561 (19)0.0063 (14)0.0040 (14)0.0038 (14)
C70.0361 (14)0.0399 (15)0.0417 (16)0.0039 (12)0.0005 (12)0.0038 (12)
C80.0383 (15)0.0369 (14)0.0433 (16)0.0022 (12)0.0041 (12)0.0054 (12)
C90.0347 (15)0.0561 (18)0.0450 (17)0.0012 (13)0.0049 (13)0.0102 (14)
C100.0498 (18)0.068 (2)0.0392 (17)0.0077 (16)0.0004 (14)0.0072 (15)
C110.063 (2)0.068 (2)0.0475 (18)0.0007 (17)0.0118 (16)0.0073 (16)
C120.0505 (19)0.087 (3)0.059 (2)0.0159 (18)0.0107 (17)0.0067 (18)
C130.0397 (16)0.069 (2)0.0493 (18)0.0076 (15)0.0010 (14)0.0013 (15)
C140.0442 (17)0.076 (2)0.0419 (17)0.0036 (16)0.0032 (14)0.0063 (15)
C150.0513 (19)0.072 (2)0.057 (2)0.0036 (17)0.0181 (16)0.0093 (17)
C160.0454 (17)0.0521 (18)0.0463 (17)0.0048 (14)0.0055 (14)0.0111 (14)
C170.0549 (19)0.0574 (19)0.0500 (18)0.0139 (15)0.0022 (15)0.0171 (15)
C180.0396 (16)0.0621 (19)0.054 (2)0.0032 (15)0.0060 (14)0.0025 (15)
C190.0413 (16)0.0467 (17)0.0552 (19)0.0076 (14)0.0074 (14)0.0049 (14)
C200.0404 (17)0.0441 (17)0.067 (2)0.0010 (14)0.0030 (16)0.0054 (15)
Cl10.0626 (6)0.0995 (7)0.0751 (6)0.0043 (5)0.0216 (5)0.0236 (5)
Cl20.0537 (5)0.0773 (6)0.0937 (7)0.0113 (4)0.0080 (5)0.0054 (5)
N10.0341 (12)0.0473 (13)0.0411 (13)0.0014 (10)0.0038 (10)0.0070 (10)
N20.0381 (13)0.0465 (13)0.0494 (15)0.0064 (11)0.0001 (11)0.0047 (11)
N30.0452 (15)0.0627 (16)0.0507 (16)0.0013 (13)0.0017 (12)0.0051 (13)
N40.0560 (19)0.080 (2)0.072 (2)0.0215 (16)0.0145 (17)0.0256 (17)
O10.094 (2)0.117 (2)0.0570 (16)0.0273 (18)0.0125 (16)0.0085 (15)
O20.078 (2)0.151 (3)0.117 (3)0.012 (2)0.0262 (18)0.065 (2)
Geometric parameters (Å, º) top
C1—C21.364 (4)C13—H130.9300
C1—C61.365 (4)C14—N11.450 (4)
C1—Cl11.737 (3)C14—C151.495 (4)
C2—C31.374 (4)C14—H14A0.9700
C2—H20.9300C14—H14B0.9700
C3—C41.372 (4)C15—Cl21.779 (3)
C3—H30.9300C15—H15A0.9700
C4—C51.392 (4)C15—H15B0.9700
C4—C71.524 (4)C16—N11.466 (3)
C5—C61.384 (4)C16—C171.525 (4)
C5—H50.9300C16—H16A0.9700
C6—H60.9300C16—H16B0.9700
C7—N11.475 (3)C17—N21.452 (4)
C7—C81.520 (4)C17—H17A0.9700
C7—H70.9800C17—H17B0.9700
C8—C131.375 (4)C18—N31.307 (4)
C8—C91.382 (4)C18—N21.350 (4)
C9—C101.368 (4)C18—H180.9300
C9—H90.9300C19—N31.353 (4)
C10—C111.376 (4)C19—C201.355 (4)
C10—H100.9300C19—N41.432 (4)
C11—C121.356 (4)C20—N21.348 (4)
C11—H110.9300C20—H200.9300
C12—C131.384 (4)N4—O21.211 (4)
C12—H120.9300N4—O11.225 (4)
C2—C1—C6121.1 (3)N1—C14—H14A108.5
C2—C1—Cl1119.2 (2)C15—C14—H14A108.5
C6—C1—Cl1119.8 (2)N1—C14—H14B108.5
C1—C2—C3119.0 (3)C15—C14—H14B108.5
C1—C2—H2120.5H14A—C14—H14B107.5
C3—C2—H2120.5C14—C15—Cl2111.8 (2)
C4—C3—C2122.8 (3)C14—C15—H15A109.2
C4—C3—H3118.6Cl2—C15—H15A109.2
C2—C3—H3118.6C14—C15—H15B109.2
C3—C4—C5116.5 (3)Cl2—C15—H15B109.2
C3—C4—C7119.3 (2)H15A—C15—H15B107.9
C5—C4—C7124.2 (2)N1—C16—C17112.0 (2)
C6—C5—C4121.8 (3)N1—C16—H16A109.2
C6—C5—H5119.1C17—C16—H16A109.2
C4—C5—H5119.1N1—C16—H16B109.2
C1—C6—C5118.9 (3)C17—C16—H16B109.2
C1—C6—H6120.6H16A—C16—H16B107.9
C5—C6—H6120.6N2—C17—C16111.8 (2)
N1—C7—C8109.3 (2)N2—C17—H17A109.3
N1—C7—C4115.8 (2)C16—C17—H17A109.3
C8—C7—C4116.5 (2)N2—C17—H17B109.3
N1—C7—H7104.6C16—C17—H17B109.3
C8—C7—H7104.6H17A—C17—H17B107.9
C4—C7—H7104.6N3—C18—N2113.2 (3)
C13—C8—C9117.5 (3)N3—C18—H18123.4
C13—C8—C7124.7 (3)N2—C18—H18123.4
C9—C8—C7117.8 (2)N3—C19—C20112.3 (3)
C10—C9—C8121.7 (3)N3—C19—N4121.4 (3)
C10—C9—H9119.2C20—C19—N4126.2 (3)
C8—C9—H9119.2N2—C20—C19105.0 (3)
C9—C10—C11119.8 (3)N2—C20—H20127.5
C9—C10—H10120.1C19—C20—H20127.5
C11—C10—H10120.1C14—N1—C16112.7 (2)
C12—C11—C10119.7 (3)C14—N1—C7113.5 (2)
C12—C11—H11120.2C16—N1—C7115.5 (2)
C10—C11—H11120.2C20—N2—C18106.5 (2)
C11—C12—C13120.4 (3)C20—N2—C17126.7 (3)
C11—C12—H12119.8C18—N2—C17126.8 (3)
C13—C12—H12119.8C18—N3—C19103.0 (3)
C8—C13—C12121.0 (3)O2—N4—O1125.0 (3)
C8—C13—H13119.5O2—N4—C19116.4 (3)
C12—C13—H13119.5O1—N4—C19118.5 (3)
N1—C14—C15115.1 (2)
C6—C1—C2—C30.6 (5)N1—C14—C15—Cl258.3 (3)
Cl1—C1—C2—C3179.4 (2)N1—C16—C17—N270.4 (3)
C1—C2—C3—C40.4 (5)N3—C19—C20—N20.3 (3)
C2—C3—C4—C51.3 (4)N4—C19—C20—N2178.3 (3)
C2—C3—C4—C7177.3 (3)C15—C14—N1—C16156.5 (3)
C3—C4—C5—C61.3 (4)C15—C14—N1—C769.7 (3)
C7—C4—C5—C6177.2 (3)C17—C16—N1—C1483.4 (3)
C2—C1—C6—C50.6 (5)C17—C16—N1—C7143.8 (2)
Cl1—C1—C6—C5179.4 (2)C8—C7—N1—C14163.5 (2)
C4—C5—C6—C10.4 (5)C4—C7—N1—C1462.6 (3)
C3—C4—C7—N1118.5 (3)C8—C7—N1—C1664.1 (3)
C5—C4—C7—N160.0 (3)C4—C7—N1—C1669.8 (3)
C3—C4—C7—C8110.9 (3)C19—C20—N2—C180.6 (3)
C5—C4—C7—C870.6 (3)C19—C20—N2—C17179.6 (3)
N1—C7—C8—C13121.7 (3)N3—C18—N2—C200.7 (3)
C4—C7—C8—C1311.9 (4)N3—C18—N2—C17179.7 (3)
N1—C7—C8—C959.8 (3)C16—C17—N2—C2070.0 (4)
C4—C7—C8—C9166.6 (2)C16—C17—N2—C18108.8 (3)
C13—C8—C9—C101.6 (4)N2—C18—N3—C190.4 (3)
C7—C8—C9—C10179.7 (3)C20—C19—N3—C180.1 (3)
C8—C9—C10—C110.7 (4)N4—C19—N3—C18178.0 (3)
C9—C10—C11—C120.5 (5)N3—C19—N4—O2178.6 (3)
C10—C11—C12—C130.9 (5)C20—C19—N4—O23.6 (5)
C9—C8—C13—C121.2 (4)N3—C19—N4—O12.0 (4)
C7—C8—C13—C12179.8 (3)C20—C19—N4—O1175.8 (3)
C11—C12—C13—C80.0 (5)

Experimental details

Crystal data
Chemical formulaC20H20Cl2N4O2
Mr419.30
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)8.8206 (16), 25.005 (5), 9.0450 (17)
β (°) 100.802 (3)
V3)1959.6 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.36
Crystal size (mm)0.32 × 0.24 × 0.18
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.903, 0.938
No. of measured, independent and
observed [I > 2σ(I)] reflections
9838, 3449, 2464
Rint0.037
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.139, 1.03
No. of reflections3449
No. of parameters253
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.49, 0.24

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

We thank Southwest University (grant Nos. SWUB2006018 and XSGX0602), the Natural Science Foundation of Chongqing (grant No. 2009BB5296) and the Research Funds for the Central Universities (XDJK2009c092) for financial support.

References

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First citationZhuang, Y. Y., Zhou, C. H., Wang, Y. F. & Li, D. H. (2008). Chin. Pharm. J. 43, 1281–1287.  CAS Google Scholar

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