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Acta Crystallogr Sect E Struct Rep Online. 2010 June 1; 66(Pt 6): o1291.
Published online 2010 May 8. doi:  10.1107/S1600536810016107
PMCID: PMC2979486

1,3-Dicyclo­hexyl-1-(4-nitro­benzo­yl)urea

Abstract

In the title compound, C20H27N3O4, both cyclo­hexane rings adopt chair conformations. The benzene ring and the amide group are oriented at a dihedral angle of 62.1 (2)°. In the crystal structure, inter­molecular N—H(...)O and C—H(...)O hydrogen bonds link the mol­ecules into chains propagating in [010], which contain R 2 2(12) ring motifs.

Related literature

For the biological activity of benzoyl­urea and N-aroylurea derivatives, see: Song et al. (2008 [triangle], 2009 [triangle]); Amornraksa et al. (2009 [triangle]). For related N-benzoyl-N,N′-dicyclo­hexyl­urea structures, see: Orea Flores et al. (2006 [triangle]); Wang & Peng (2008 [triangle]).

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Object name is e-66-o1291-scheme1.jpg

Experimental

Crystal data

  • C20H27N3O4
  • M r = 373.45
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1291-efi1.jpg
  • a = 25.294 (2) Å
  • b = 9.5757 (7) Å
  • c = 16.6943 (14) Å
  • β = 105.140 (2)°
  • V = 3903.1 (5) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 292 K
  • 0.25 × 0.20 × 0.20 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker 1999 [triangle]) T min = 0.836, T max = 0.982
  • 22623 measured reflections
  • 5012 independent reflections
  • 3152 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.049
  • wR(F 2) = 0.138
  • S = 1.02
  • 5012 reflections
  • 244 parameters
  • H-atom parameters constrained
  • Δρmax = 0.15 e Å−3
  • Δρmin = −0.14 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT-Plus (Bruker, 2004 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and Mercury (Macrae et al., 2008 [triangle]); software used to prepare material for publication: PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810016107/hb5432sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810016107/hb5432Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank Dr Babu Varghese, SAIF, IIT-Madras, Chennai, for providing data-collection facilities.

supplementary crystallographic information

Comment

Benzoylurea derivatives act as antimitotic (Song et al., 2008) and antiproliferative (Song et al., 2009) agents. Some of the N-aroylurea analogs have been found to exhibit antioxidant activity (Amornraksa et al., 2009). We report here the crystal structure of the title compound, (I), an aroylurea.

In the title molecule (Fig. 1), both cyclohexane rings adopt chair conformations. The benzoyl carbonyl group is twisted away from the N–H group and as a result no intramolecular N—H···O hydrogen bond is formed. The dihedral angle between the N1/C7/O1 and N2/C14/O2 planes is 65.0 (2)°. The amide group (C7/O1/N1) and the benzene ring (C15–C20) are oriented at a dihedral angle of 62.1 (1)°. The nitro group is almost coplanar with the attached benzene ring [C19—C18—N3—O3 = -0.8 (3)° and C17—C18—N3—O4 = -1.6 (3)°]. Bond lengths and angles are comparable to those observed in N-benzoyl-N,N'-dicyclohexylurea (Orea Flores et al., 2006) and N-(4-bromobenzoyl)-N,N-dicyclohexylurea (Wang & Peng, 2008).

In the crystal structure, N1—H1A···O1i and C1—H1···O2ii hydrogen bonds (symmetry codes as in Table 1) generate R22(12) ring motifs which are fused into a ribbon-like structure along the b axis (Fig.2).

Experimental

4-Nitrobenzoic acid (1 g, 5.9 mmol) and dicyclohexylcarbodiimide (1.203 g, 5.9 mmol) were dissolved in dichloromethane (30 ml). The resulting mixture was stirred overnight and then the solvent was removed by rotary evaporator. The product was isolated by column chromatography by using ethyl acetate-hexane (1:9) as eluent. Pale yellow blocks of (I) were obtained by slow evaporation of an ethanolic solution over a period of two weeks.

Refinement

H atoms were initially located in a difference Fourier map and later placed in idealized positions and constrained to ride on their parent atoms, with N–H = 0.86 Å, C–H = 0.93–0.98 Å and Uiso(H) = 1.2Ueq(C,N). The Uij parameters of the nitro group atoms indicate possible disorder but attempts to model the disorder were not successful. Beamstop affected reflection 200 was omitted during the refinement.

Figures

Fig. 1.
The molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level.
Fig. 2.
Part of the crystal structure of (I), showing fused R22(12) ring motifs generating a molecular ribbon extending along the b axis.

Crystal data

C20H27N3O4F(000) = 1600
Mr = 373.45Dx = 1.271 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 4827 reflections
a = 25.294 (2) Åθ = 2.5–23.4°
b = 9.5757 (7) ŵ = 0.09 mm1
c = 16.6943 (14) ÅT = 292 K
β = 105.140 (2)°Block, pale-yellow
V = 3903.1 (5) Å30.25 × 0.20 × 0.20 mm
Z = 8

Data collection

Bruker Kappa APEXII CCD diffractometer5012 independent reflections
Radiation source: fine-focus sealed tube3152 reflections with I > 2σ(I)
graphiteRint = 0.031
ω and [var phi] scanθmax = 28.7°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Bruker 1999)h = −34→34
Tmin = 0.836, Tmax = 0.982k = −12→12
22623 measured reflectionsl = −22→22

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.138H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.0549P)2 + 1.482P] where P = (Fo2 + 2Fc2)/3
5012 reflections(Δ/σ)max = 0.001
244 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = −0.14 e Å3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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)

xyzUiso*/Ueq
C10.18614 (6)0.20858 (14)0.12793 (9)0.0419 (3)
H10.19690.11160.12200.050*
C20.12619 (7)0.2094 (2)0.12851 (11)0.0651 (5)
H2A0.11510.30390.13740.078*
H2B0.12120.15170.17380.078*
C30.09045 (7)0.1538 (3)0.04623 (12)0.0795 (6)
H3A0.09910.05630.04020.095*
H3B0.05220.15960.04660.095*
C40.09915 (8)0.2346 (2)−0.02572 (12)0.0786 (6)
H4A0.08700.3301−0.02280.094*
H4B0.07750.1938−0.07700.094*
C50.15886 (8)0.2338 (2)−0.02557 (11)0.0713 (5)
H5A0.16380.2902−0.07130.086*
H5B0.17000.1391−0.03370.086*
C60.19480 (8)0.29061 (19)0.05559 (10)0.0603 (4)
H6A0.23300.28500.05490.072*
H6B0.18600.38800.06150.072*
C70.25502 (6)0.18506 (14)0.26110 (9)0.0405 (3)
C80.34370 (6)0.27308 (16)0.35126 (10)0.0511 (4)
H80.35450.35510.38690.061*
C90.36104 (7)0.2997 (2)0.27233 (12)0.0665 (5)
H9A0.34360.38410.24600.080*
H9B0.34920.22260.23410.080*
C100.42312 (8)0.3153 (3)0.29111 (15)0.0843 (6)
H10A0.43350.32690.23960.101*
H10B0.43450.39820.32460.101*
C110.45178 (8)0.1898 (3)0.33654 (17)0.0955 (8)
H11A0.49110.20370.34930.115*
H11B0.44270.10810.30130.115*
C120.43525 (8)0.1653 (3)0.41589 (16)0.1003 (8)
H12A0.44710.24340.45320.120*
H12B0.45310.08170.44280.120*
C130.37307 (7)0.1487 (2)0.39846 (13)0.0748 (6)
H13A0.36170.06440.36630.090*
H13B0.36310.13930.45050.090*
C140.25633 (7)0.32416 (15)0.38509 (9)0.0478 (4)
C150.19665 (6)0.29435 (15)0.37139 (9)0.0462 (3)
C160.16036 (8)0.40464 (17)0.36337 (13)0.0689 (5)
H160.17320.49560.36320.083*
C170.10558 (9)0.3818 (2)0.35558 (14)0.0784 (6)
H170.08110.45600.34890.094*
C180.08794 (7)0.2471 (2)0.35787 (11)0.0611 (4)
C190.12263 (7)0.13583 (19)0.36631 (11)0.0599 (4)
H190.10950.04530.36740.072*
C200.17750 (7)0.15920 (16)0.37322 (10)0.0521 (4)
H200.20160.08420.37910.063*
N10.22096 (5)0.26334 (11)0.20560 (7)0.0426 (3)
H1A0.21920.35100.21570.051*
N20.28337 (5)0.25964 (12)0.33451 (7)0.0450 (3)
N30.02944 (8)0.2204 (3)0.35113 (12)0.0897 (6)
O10.26427 (4)0.06149 (10)0.25260 (6)0.0535 (3)
O20.27950 (5)0.40101 (12)0.44180 (7)0.0660 (3)
O30.01453 (7)0.1016 (3)0.35244 (15)0.1366 (8)
O4−0.00053 (8)0.3209 (3)0.34562 (14)0.1356 (8)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0420 (8)0.0411 (7)0.0381 (8)0.0019 (6)0.0026 (6)−0.0032 (6)
C20.0507 (10)0.0968 (13)0.0464 (10)−0.0144 (9)0.0101 (8)−0.0049 (9)
C30.0459 (10)0.1293 (18)0.0568 (12)−0.0117 (11)0.0016 (8)−0.0154 (12)
C40.0766 (14)0.0941 (14)0.0491 (11)0.0318 (11)−0.0122 (9)−0.0059 (10)
C50.0924 (15)0.0818 (12)0.0369 (9)−0.0024 (10)0.0122 (9)0.0032 (8)
C60.0683 (11)0.0700 (10)0.0455 (9)−0.0077 (9)0.0199 (8)−0.0026 (8)
C70.0382 (7)0.0415 (7)0.0391 (8)−0.0064 (6)0.0052 (6)−0.0011 (6)
C80.0437 (8)0.0566 (8)0.0464 (9)−0.0144 (7)0.0000 (7)−0.0014 (7)
C90.0496 (10)0.0845 (12)0.0617 (11)−0.0081 (9)0.0079 (8)0.0146 (9)
C100.0558 (12)0.1142 (17)0.0825 (15)−0.0205 (11)0.0175 (10)0.0039 (13)
C110.0434 (11)0.1230 (19)0.109 (2)−0.0024 (12)−0.0003 (11)−0.0069 (16)
C120.0559 (12)0.1229 (19)0.1000 (19)−0.0031 (12)−0.0191 (12)0.0269 (15)
C130.0529 (11)0.0874 (13)0.0695 (13)−0.0088 (9)−0.0099 (9)0.0259 (10)
C140.0610 (10)0.0460 (7)0.0338 (8)−0.0122 (7)0.0075 (7)0.0021 (6)
C150.0602 (10)0.0465 (8)0.0329 (7)−0.0064 (7)0.0142 (7)−0.0015 (6)
C160.0856 (14)0.0472 (9)0.0866 (14)0.0010 (8)0.0453 (11)0.0004 (9)
C170.0818 (14)0.0768 (13)0.0902 (15)0.0217 (10)0.0466 (12)0.0135 (11)
C180.0551 (10)0.0856 (12)0.0461 (10)−0.0019 (9)0.0198 (8)0.0029 (8)
C190.0637 (11)0.0619 (10)0.0558 (10)−0.0155 (8)0.0188 (8)−0.0026 (8)
C200.0582 (10)0.0475 (8)0.0505 (9)−0.0055 (7)0.0140 (7)0.0030 (7)
N10.0465 (7)0.0358 (6)0.0405 (7)0.0001 (5)0.0020 (5)−0.0033 (5)
N20.0433 (7)0.0482 (7)0.0384 (7)−0.0094 (5)0.0019 (5)−0.0027 (5)
N30.0614 (12)0.1421 (19)0.0727 (12)−0.0012 (13)0.0299 (9)0.0005 (12)
O10.0563 (7)0.0400 (5)0.0544 (7)0.0028 (4)−0.0028 (5)−0.0017 (5)
O20.0836 (9)0.0709 (7)0.0413 (6)−0.0298 (6)0.0121 (6)−0.0137 (5)
O30.0837 (12)0.1591 (19)0.183 (2)−0.0499 (13)0.0636 (13)−0.0461 (16)
O40.0759 (11)0.192 (2)0.1528 (19)0.0377 (13)0.0546 (12)0.0442 (16)

Geometric parameters (Å, °)

C1—N11.4613 (17)C10—C111.503 (3)
C1—C61.504 (2)C10—H10A0.97
C1—C21.519 (2)C10—H10B0.97
C1—H10.98C11—C121.508 (4)
C2—C31.530 (2)C11—H11A0.97
C2—H2A0.97C11—H11B0.97
C2—H2B0.97C12—C131.531 (3)
C3—C41.493 (3)C12—H12A0.97
C3—H3A0.97C12—H12B0.97
C3—H3B0.97C13—H13A0.97
C4—C51.510 (3)C13—H13B0.97
C4—H4A0.97C14—O21.2213 (17)
C4—H4B0.97C14—N21.365 (2)
C5—C61.521 (2)C14—C151.494 (2)
C5—H5A0.97C15—C161.383 (2)
C5—H5B0.97C15—C201.385 (2)
C6—H6A0.97C16—C171.375 (3)
C6—H6B0.97C16—H160.93
C7—O11.2217 (16)C17—C181.369 (3)
C7—N11.3213 (18)C17—H170.93
C7—N21.4377 (17)C18—C191.364 (3)
C8—N21.4834 (19)C18—N31.477 (3)
C8—C131.512 (2)C19—C201.381 (2)
C8—C91.515 (2)C19—H190.93
C8—H80.98C20—H200.93
C9—C101.526 (2)N1—H1A0.86
C9—H9A0.97N3—O31.200 (3)
C9—H9B0.97N3—O41.213 (3)
N1—C1—C6110.17 (12)C9—C10—H10A109.4
N1—C1—C2111.33 (12)C11—C10—H10B109.4
C6—C1—C2110.94 (13)C9—C10—H10B109.4
N1—C1—H1108.1H10A—C10—H10B108.0
C6—C1—H1108.1C10—C11—C12111.1 (2)
C2—C1—H1108.1C10—C11—H11A109.4
C1—C2—C3110.45 (15)C12—C11—H11A109.4
C1—C2—H2A109.6C10—C11—H11B109.4
C3—C2—H2A109.6C12—C11—H11B109.4
C1—C2—H2B109.6H11A—C11—H11B108.0
C3—C2—H2B109.6C11—C12—C13110.85 (17)
H2A—C2—H2B108.1C11—C12—H12A109.5
C4—C3—C2111.43 (17)C13—C12—H12A109.5
C4—C3—H3A109.3C11—C12—H12B109.5
C2—C3—H3A109.3C13—C12—H12B109.5
C4—C3—H3B109.3H12A—C12—H12B108.1
C2—C3—H3B109.3C8—C13—C12110.96 (16)
H3A—C3—H3B108.0C8—C13—H13A109.4
C3—C4—C5110.71 (15)C12—C13—H13A109.4
C3—C4—H4A109.5C8—C13—H13B109.4
C5—C4—H4A109.5C12—C13—H13B109.4
C3—C4—H4B109.5H13A—C13—H13B108.0
C5—C4—H4B109.5O2—C14—N2122.40 (15)
H4A—C4—H4B108.1O2—C14—C15119.65 (15)
C4—C5—C6111.38 (16)N2—C14—C15117.92 (12)
C4—C5—H5A109.4C16—C15—C20119.26 (16)
C6—C5—H5A109.4C16—C15—C14119.19 (14)
C4—C5—H5B109.4C20—C15—C14121.35 (14)
C6—C5—H5B109.4C17—C16—C15120.97 (16)
H5A—C5—H5B108.0C17—C16—H16119.5
C1—C6—C5110.49 (14)C15—C16—H16119.5
C1—C6—H6A109.6C18—C17—C16118.38 (17)
C5—C6—H6A109.6C18—C17—H17120.8
C1—C6—H6B109.6C16—C17—H17120.8
C5—C6—H6B109.6C19—C18—C17122.23 (17)
H6A—C6—H6B108.1C19—C18—N3118.54 (18)
O1—C7—N1125.28 (13)C17—C18—N3119.23 (19)
O1—C7—N2120.81 (12)C18—C19—C20119.19 (16)
N1—C7—N2113.87 (12)C18—C19—H19120.4
N2—C8—C13111.79 (13)C20—C19—H19120.4
N2—C8—C9111.58 (12)C19—C20—C15119.96 (16)
C13—C8—C9111.80 (16)C19—C20—H20120.0
N2—C8—H8107.1C15—C20—H20120.0
C13—C8—H8107.1C7—N1—C1123.38 (11)
C9—C8—H8107.1C7—N1—H1A118.3
C8—C9—C10110.73 (15)C1—N1—H1A118.3
C8—C9—H9A109.5C14—N2—C7122.22 (12)
C10—C9—H9A109.5C14—N2—C8120.06 (12)
C8—C9—H9B109.5C7—N2—C8117.59 (12)
C10—C9—H9B109.5O3—N3—O4124.0 (2)
H9A—C9—H9B108.1O3—N3—C18118.4 (2)
C11—C10—C9111.10 (17)O4—N3—C18117.5 (2)
C11—C10—H10A109.4
N1—C1—C2—C3179.16 (15)C17—C18—C19—C200.3 (3)
C6—C1—C2—C356.1 (2)N3—C18—C19—C20−179.59 (16)
C1—C2—C3—C4−56.0 (2)C18—C19—C20—C15−0.1 (3)
C2—C3—C4—C556.1 (2)C16—C15—C20—C190.6 (2)
C3—C4—C5—C6−56.5 (2)C14—C15—C20—C19175.33 (14)
N1—C1—C6—C5179.75 (13)O1—C7—N1—C14.9 (2)
C2—C1—C6—C5−56.51 (19)N2—C7—N1—C1−177.33 (12)
C4—C5—C6—C156.7 (2)C6—C1—N1—C7−126.35 (15)
N2—C8—C9—C10179.16 (15)C2—C1—N1—C7110.13 (16)
C13—C8—C9—C10−54.8 (2)O2—C14—N2—C7−171.22 (13)
C8—C9—C10—C1155.8 (2)C15—C14—N2—C710.96 (19)
C9—C10—C11—C12−57.2 (3)O2—C14—N2—C84.6 (2)
C10—C11—C12—C1356.8 (3)C15—C14—N2—C8−173.21 (12)
N2—C8—C13—C12−179.41 (17)O1—C7—N2—C14−121.45 (16)
C9—C8—C13—C1254.7 (2)N1—C7—N2—C1460.66 (18)
C11—C12—C13—C8−55.3 (3)O1—C7—N2—C862.63 (18)
O2—C14—C15—C1653.2 (2)N1—C7—N2—C8−115.27 (14)
N2—C14—C15—C16−128.91 (16)C13—C8—N2—C1497.56 (18)
O2—C14—C15—C20−121.55 (17)C9—C8—N2—C14−136.42 (15)
N2—C14—C15—C2056.33 (19)C13—C8—N2—C7−86.42 (17)
C20—C15—C16—C17−1.3 (3)C9—C8—N2—C739.60 (18)
C14—C15—C16—C17−176.15 (17)C19—C18—N3—O3−0.8 (3)
C15—C16—C17—C181.5 (3)C17—C18—N3—O3179.3 (2)
C16—C17—C18—C19−1.0 (3)C19—C18—N3—O4178.3 (2)
C16—C17—C18—N3178.90 (17)C17—C18—N3—O4−1.6 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···O1i0.862.102.9396 (15)166
C1—H1···O2ii0.982.433.3636 (18)160

Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) −x+1/2, y−1/2, −z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB5432).

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