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Acta Crystallogr Sect E Struct Rep Online. 2011 November 1; 67(Pt 11): o3060.
Published online 2011 October 29. doi:  10.1107/S160053681104342X
PMCID: PMC3247451

Ethyl 2-(4-bromophenyl)-1-[3-(1H-imidazol-1-yl)prop­yl]-1H-benzimidazole-5-carboxyl­ate monohydrate

Abstract

In the title compound, C22H21BrN4O2·H2O, the two pyrazole rings are essentially planar [maximum deviations 0.002 (1) and 0.002 (1) Å], and form a dihedral angle of 73.46 (9)°. The dihedral angle between the benzene rings is 29.33 (7)°. In the crystal, mol­ecules are connected via C—H(...)O and O—H(...)N hydrogen bonds, forming layers in the ab plane.

Related literature

For applications of benzimidazole derivatives, see: Garuti et al. (2000 [triangle]); Rao et al. (2002 [triangle]); Thakurdesai et al. (2007 [triangle]); Yoon et al. (2011 [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-67-o3060-scheme1.jpg

Experimental

Crystal data

  • C22H21BrN4O2·H2O
  • M r = 471.35
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-67-o3060-efi1.jpg
  • a = 9.1854 (1) Å
  • b = 16.7389 (2) Å
  • c = 13.7379 (2) Å
  • β = 98.283 (1)°
  • V = 2090.22 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 2.00 mm−1
  • T = 100 K
  • 0.47 × 0.42 × 0.41 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.452, T max = 0.494
  • 28847 measured reflections
  • 7482 independent reflections
  • 5514 reflections with I > 2σ(I)
  • R int = 0.032

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.085
  • S = 1.03
  • 7482 reflections
  • 280 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.63 e Å−3
  • Δρmin = −0.34 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S160053681104342X/tk5002sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S160053681104342X/tk5002Isup2.hkl

Supplementary material file. DOI: 10.1107/S160053681104342X/tk5002Isup3.cml

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

Acknowledgments

YKY, MAA and TSC thank the Department of Pharmaco­genetic and Novel Therapeutic Research, Institute for Research in Mol­ecular Medicine, Universiti Sains Malaysia, Penang. This work was funded through a Research Grant (No. RUC 1001/PSK/8620012). HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for a Research University grant (No. 1001/PFIZIK/811160). MH thanks Universiti Sains Malaysia for a postdoctoral research fellowship.

supplementary crystallographic information

Comment

Benzimidazole derivatives are of wide interest because of their diverse biological activities and various clinical applications. Benzimidazoles are a class of bioactive heterocyclic compounds which exhibit a wide range of activities such as anti-proliferative (Garuti et al., 2000), anti-HIV (Rao et al., 2002), anti-inflammatory and anthelmintic (Thakurdesai et al., 2007) properties. As part of our on-going structural studies of benzimidazole derivatives (Yoon et al., 2011), we now report the structure of the title compound.

In the title compound (Fig. 1), the two pyrazole (N1,N2/C7,C8/C13 and N3,N4/C20–C22) rings are essentially planar, with a maximum deviation of 0.002 (1) Å for atom C8 and 0.002 (1) Å for atom N3. The dihedral angle between the two pyrazole (N1,N2/C7,C8/C13 : N3,N4/C20–C22) rings is 73.46 (9)° and between the two benzene (C8–C13 : C1–C6) rings is 29.33 (7)°.

In the crystal structure, molecules are connected via intermolecular C—H···O and O—H···N (Table 1) hydrogen bonds, forming layers in the ab plane.

Experimental

Ethyl-4-(3-(1H-imidazol-1-yl-propylamino)-3-aminobenzoate (0.84 mmol) and sodium metabisulfite adduct of bromobenzaldehyde (1.68 mmol) were dissolved in DMF. The reaction mixture was refluxed at 130°C for 2 h. After completion, the reaction mixture was diluted in ethyl acetate (20 ml) and washed with water (20 ml). The organic layer was collected, dried over Na2SO4 and then evaporated in vacuo to yield the product. The product was recrystallised from its ethyl acetate solution.

Refinement

Atoms H2W1 and H1W1 were located from a difference Fourier maps and refined freely [O—H = 0.80 (3)–0.92 (3) Å]. The remaining H atoms were positioned geometrically [C—H = 0.95–0.99 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5Ueq(C). A rotating group model was applied to the methyl group.

Figures

Fig. 1.
The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids.

Crystal data

C22H21BrN4O2·H2OF(000) = 968
Mr = 471.35Dx = 1.498 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 9939 reflections
a = 9.1854 (1) Åθ = 2.5–31.3°
b = 16.7389 (2) ŵ = 2.00 mm1
c = 13.7379 (2) ÅT = 100 K
β = 98.283 (1)°Block, yellow
V = 2090.22 (5) Å30.47 × 0.42 × 0.41 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer7482 independent reflections
Radiation source: fine-focus sealed tube5514 reflections with I > 2σ(I)
graphiteRint = 0.032
[var phi] and ω scansθmax = 32.4°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −13→13
Tmin = 0.452, Tmax = 0.494k = −25→17
28847 measured reflectionsl = −20→19

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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.085H atoms treated by a mixture of independent and constrained refinement
S = 1.03w = 1/[σ2(Fo2) + (0.0386P)2 + 0.518P] where P = (Fo2 + 2Fc2)/3
7482 reflections(Δ/σ)max = 0.001
280 parametersΔρmax = 0.63 e Å3
0 restraintsΔρmin = −0.34 e Å3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Br10.123446 (18)0.050021 (9)0.931417 (13)0.02720 (6)
O10.40323 (12)0.80153 (6)0.87745 (9)0.0247 (2)
O20.17930 (13)0.76409 (7)0.90802 (9)0.0260 (2)
N10.23105 (14)0.45313 (7)0.89922 (10)0.0199 (3)
N20.46106 (14)0.42561 (7)0.87069 (9)0.0174 (2)
N30.71289 (14)0.23427 (8)0.76584 (10)0.0216 (3)
N40.61875 (16)0.11193 (8)0.75103 (11)0.0265 (3)
C10.18138 (17)0.29413 (9)0.95735 (11)0.0207 (3)
H1A0.14110.33630.99130.025*
C20.13384 (17)0.21676 (9)0.96832 (12)0.0209 (3)
H2A0.06220.20561.00990.025*
C30.19242 (17)0.15558 (9)0.91768 (11)0.0197 (3)
C40.29838 (17)0.17037 (9)0.85769 (12)0.0212 (3)
H4A0.33850.12790.82420.025*
C50.34509 (17)0.24861 (9)0.84737 (11)0.0201 (3)
H5A0.41700.25950.80590.024*
C60.28788 (16)0.31134 (8)0.89703 (11)0.0174 (3)
C70.32652 (16)0.39632 (9)0.88789 (11)0.0181 (3)
C80.44933 (16)0.50829 (8)0.87200 (11)0.0175 (3)
C90.54989 (17)0.56882 (9)0.86054 (12)0.0207 (3)
H9A0.64730.55740.84900.025*
C100.50014 (17)0.64649 (9)0.86687 (11)0.0204 (3)
H10A0.56480.68950.85890.025*
C110.35573 (17)0.66335 (8)0.88480 (11)0.0188 (3)
C120.25683 (17)0.60237 (9)0.89609 (11)0.0201 (3)
H12A0.15950.61370.90780.024*
C130.30541 (16)0.52409 (9)0.88960 (11)0.0186 (3)
C140.30222 (17)0.74678 (9)0.89169 (11)0.0209 (3)
C150.35706 (19)0.88442 (9)0.88439 (14)0.0271 (4)
H15A0.32010.89360.94770.033*
H15B0.27710.89700.83020.033*
C160.4876 (2)0.93640 (10)0.87762 (16)0.0345 (4)
H16A0.46090.99240.88590.052*
H16B0.51960.92930.81310.052*
H16C0.56790.92150.92940.052*
C170.59623 (16)0.38267 (9)0.85909 (11)0.0186 (3)
H17A0.59340.32900.88910.022*
H17B0.68140.41180.89480.022*
C180.61756 (17)0.37351 (9)0.75149 (12)0.0209 (3)
H18A0.52620.35230.71320.025*
H18B0.63760.42650.72420.025*
C190.74492 (18)0.31714 (9)0.74141 (13)0.0241 (3)
H19A0.76690.31930.67300.029*
H19B0.83350.33540.78540.029*
C200.62362 (17)0.18286 (9)0.70936 (12)0.0223 (3)
H20A0.57060.19620.64690.027*
C210.7101 (2)0.11857 (11)0.83933 (14)0.0318 (4)
H21A0.72970.07690.88640.038*
C220.76797 (19)0.19311 (11)0.84941 (13)0.0310 (4)
H22A0.83380.21300.90370.037*
O1W0.41413 (16)0.03202 (9)0.36883 (13)0.0409 (4)
H2W10.406 (4)−0.015 (2)0.334 (2)0.092 (10)*
H1W10.496 (3)0.0391 (14)0.3976 (19)0.052 (8)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.02447 (9)0.01647 (7)0.04180 (11)−0.00321 (6)0.00871 (7)0.00484 (6)
O10.0236 (6)0.0141 (5)0.0369 (7)−0.0002 (4)0.0064 (5)0.0000 (4)
O20.0224 (6)0.0207 (5)0.0355 (7)0.0011 (4)0.0059 (5)−0.0032 (5)
N10.0168 (6)0.0168 (6)0.0267 (7)−0.0011 (5)0.0054 (5)0.0010 (5)
N20.0152 (6)0.0147 (5)0.0232 (6)−0.0008 (4)0.0056 (5)0.0004 (5)
N30.0179 (6)0.0207 (6)0.0270 (7)0.0007 (5)0.0065 (5)−0.0022 (5)
N40.0254 (7)0.0227 (7)0.0324 (8)0.0012 (5)0.0077 (6)0.0011 (6)
C10.0190 (7)0.0200 (7)0.0239 (8)−0.0014 (6)0.0056 (6)−0.0009 (6)
C20.0179 (7)0.0215 (7)0.0239 (8)−0.0016 (6)0.0054 (6)0.0029 (6)
C30.0187 (7)0.0157 (6)0.0245 (8)−0.0022 (5)0.0025 (6)0.0041 (6)
C40.0213 (8)0.0178 (7)0.0250 (8)0.0001 (6)0.0051 (6)0.0002 (6)
C50.0190 (7)0.0193 (7)0.0232 (8)−0.0012 (5)0.0070 (6)0.0010 (6)
C60.0158 (7)0.0170 (6)0.0197 (7)−0.0021 (5)0.0032 (5)0.0013 (5)
C70.0178 (7)0.0172 (6)0.0198 (7)−0.0014 (5)0.0039 (5)0.0003 (5)
C80.0180 (7)0.0149 (6)0.0199 (7)−0.0001 (5)0.0039 (5)−0.0004 (5)
C90.0176 (7)0.0197 (7)0.0255 (8)−0.0019 (5)0.0056 (6)0.0000 (6)
C100.0205 (7)0.0174 (6)0.0237 (8)−0.0035 (6)0.0042 (6)0.0011 (6)
C110.0199 (7)0.0164 (6)0.0199 (7)−0.0001 (5)0.0023 (6)−0.0006 (5)
C120.0169 (7)0.0196 (7)0.0238 (8)0.0003 (5)0.0031 (6)0.0003 (6)
C130.0166 (7)0.0172 (6)0.0221 (7)−0.0019 (5)0.0035 (6)0.0008 (5)
C140.0214 (8)0.0186 (7)0.0221 (8)−0.0010 (6)0.0007 (6)−0.0014 (6)
C150.0292 (9)0.0142 (7)0.0384 (10)0.0025 (6)0.0062 (7)−0.0004 (6)
C160.0313 (10)0.0184 (8)0.0557 (12)−0.0001 (6)0.0127 (9)−0.0008 (7)
C170.0162 (7)0.0175 (6)0.0229 (7)0.0004 (5)0.0055 (6)0.0002 (5)
C180.0208 (7)0.0183 (7)0.0250 (8)−0.0012 (6)0.0079 (6)−0.0007 (6)
C190.0208 (8)0.0213 (7)0.0325 (9)−0.0039 (6)0.0113 (6)−0.0039 (6)
C200.0211 (8)0.0215 (7)0.0250 (8)−0.0002 (6)0.0063 (6)−0.0018 (6)
C210.0301 (9)0.0293 (9)0.0351 (10)0.0053 (7)0.0013 (8)0.0065 (7)
C220.0259 (9)0.0338 (9)0.0313 (9)0.0032 (7)−0.0027 (7)0.0001 (7)
O1W0.0218 (7)0.0354 (8)0.0648 (10)0.0047 (6)0.0035 (7)−0.0090 (7)

Geometric parameters (Å, °)

Br1—C31.8957 (14)C9—H9A0.9500
O1—C141.3384 (19)C10—C111.412 (2)
O1—C151.4579 (18)C10—H10A0.9500
O2—C141.2174 (19)C11—C121.390 (2)
N1—C71.3179 (19)C11—C141.488 (2)
N1—C131.3860 (18)C12—C131.391 (2)
N2—C71.3811 (19)C12—H12A0.9500
N2—C81.3884 (18)C15—C161.495 (2)
N2—C171.4630 (19)C15—H15A0.9900
N3—C201.353 (2)C15—H15B0.9900
N3—C221.372 (2)C16—H16A0.9800
N3—C191.4668 (19)C16—H16B0.9800
N4—C201.322 (2)C16—H16C0.9800
N4—C211.376 (2)C17—C181.527 (2)
C1—C21.382 (2)C17—H17A0.9900
C1—C61.400 (2)C17—H17B0.9900
C1—H1A0.9500C18—C191.525 (2)
C2—C31.389 (2)C18—H18A0.9900
C2—H2A0.9500C18—H18B0.9900
C3—C41.385 (2)C19—H19A0.9900
C4—C51.392 (2)C19—H19B0.9900
C4—H4A0.9500C20—H20A0.9500
C5—C61.396 (2)C21—C221.355 (3)
C5—H5A0.9500C21—H21A0.9500
C6—C71.476 (2)C22—H22A0.9500
C8—C91.395 (2)O1W—H2W10.92 (3)
C8—C131.403 (2)O1W—H1W10.80 (3)
C9—C101.385 (2)
C14—O1—C15115.33 (12)N1—C13—C8110.14 (13)
C7—N1—C13105.17 (13)C12—C13—C8120.50 (14)
C7—N2—C8106.18 (12)O2—C14—O1123.01 (14)
C7—N2—C17129.68 (12)O2—C14—C11123.97 (14)
C8—N2—C17124.04 (12)O1—C14—C11113.02 (13)
C20—N3—C22106.29 (14)O1—C15—C16107.83 (14)
C20—N3—C19126.52 (14)O1—C15—H15A110.1
C22—N3—C19127.19 (14)C16—C15—H15A110.1
C20—N4—C21104.76 (14)O1—C15—H15B110.1
C2—C1—C6121.07 (15)C16—C15—H15B110.1
C2—C1—H1A119.5H15A—C15—H15B108.5
C6—C1—H1A119.5C15—C16—H16A109.5
C1—C2—C3119.01 (15)C15—C16—H16B109.5
C1—C2—H2A120.5H16A—C16—H16B109.5
C3—C2—H2A120.5C15—C16—H16C109.5
C4—C3—C2121.48 (14)H16A—C16—H16C109.5
C4—C3—Br1119.95 (12)H16B—C16—H16C109.5
C2—C3—Br1118.56 (12)N2—C17—C18112.59 (12)
C3—C4—C5118.83 (14)N2—C17—H17A109.1
C3—C4—H4A120.6C18—C17—H17A109.1
C5—C4—H4A120.6N2—C17—H17B109.1
C4—C5—C6120.99 (14)C18—C17—H17B109.1
C4—C5—H5A119.5H17A—C17—H17B107.8
C6—C5—H5A119.5C19—C18—C17110.93 (13)
C5—C6—C1118.62 (13)C19—C18—H18A109.5
C5—C6—C7124.85 (14)C17—C18—H18A109.5
C1—C6—C7116.47 (13)C19—C18—H18B109.5
N1—C7—N2113.02 (13)C17—C18—H18B109.5
N1—C7—C6120.87 (13)H18A—C18—H18B108.0
N2—C7—C6126.07 (13)N3—C19—C18112.50 (13)
N2—C8—C9131.96 (14)N3—C19—H19A109.1
N2—C8—C13105.48 (12)C18—C19—H19A109.1
C9—C8—C13122.55 (13)N3—C19—H19B109.1
C10—C9—C8116.42 (14)C18—C19—H19B109.1
C10—C9—H9A121.8H19A—C19—H19B107.8
C8—C9—H9A121.8N4—C20—N3112.23 (15)
C9—C10—C11121.69 (14)N4—C20—H20A123.9
C9—C10—H10A119.2N3—C20—H20A123.9
C11—C10—H10A119.2C22—C21—N4110.16 (15)
C12—C11—C10121.21 (14)C22—C21—H21A124.9
C12—C11—C14117.06 (14)N4—C21—H21A124.9
C10—C11—C14121.73 (13)C21—C22—N3106.55 (15)
C11—C12—C13117.63 (14)C21—C22—H22A126.7
C11—C12—H12A121.2N3—C22—H22A126.7
C13—C12—H12A121.2H2W1—O1W—H1W1113 (3)
N1—C13—C12129.35 (14)
C6—C1—C2—C3−0.6 (2)C14—C11—C12—C13179.87 (13)
C1—C2—C3—C40.8 (2)C7—N1—C13—C12−179.26 (15)
C1—C2—C3—Br1−178.80 (11)C7—N1—C13—C80.03 (17)
C2—C3—C4—C5−0.9 (2)C11—C12—C13—N1179.06 (15)
Br1—C3—C4—C5178.77 (11)C11—C12—C13—C8−0.2 (2)
C3—C4—C5—C60.6 (2)N2—C8—C13—N10.23 (16)
C4—C5—C6—C1−0.4 (2)C9—C8—C13—N1−179.16 (14)
C4—C5—C6—C7−177.66 (14)N2—C8—C13—C12179.59 (13)
C2—C1—C6—C50.3 (2)C9—C8—C13—C120.2 (2)
C2—C1—C6—C7177.85 (13)C15—O1—C14—O21.0 (2)
C13—N1—C7—N2−0.29 (17)C15—O1—C14—C11−179.41 (13)
C13—N1—C7—C6177.75 (13)C12—C11—C14—O21.2 (2)
C8—N2—C7—N10.43 (17)C10—C11—C14—O2−179.21 (15)
C17—N2—C7—N1176.78 (14)C12—C11—C14—O1−178.39 (13)
C8—N2—C7—C6−177.48 (14)C10—C11—C14—O11.2 (2)
C17—N2—C7—C6−1.1 (2)C14—O1—C15—C16173.90 (14)
C5—C6—C7—N1150.20 (15)C7—N2—C17—C18100.34 (17)
C1—C6—C7—N1−27.1 (2)C8—N2—C17—C18−83.90 (17)
C5—C6—C7—N2−32.0 (2)N2—C17—C18—C19−170.67 (12)
C1—C6—C7—N2150.63 (15)C20—N3—C19—C1875.0 (2)
C7—N2—C8—C9178.93 (16)C22—N3—C19—C18−105.67 (18)
C17—N2—C8—C92.3 (2)C17—C18—C19—N368.15 (17)
C7—N2—C8—C13−0.38 (15)C21—N4—C20—N30.10 (19)
C17—N2—C8—C13−176.99 (13)C22—N3—C20—N4−0.28 (19)
N2—C8—C9—C10−179.58 (15)C19—N3—C20—N4179.12 (14)
C13—C8—C9—C10−0.4 (2)C20—N4—C21—C220.1 (2)
C8—C9—C10—C110.5 (2)N4—C21—C22—N3−0.3 (2)
C9—C10—C11—C12−0.5 (2)C20—N3—C22—C210.35 (19)
C9—C10—C11—C14179.95 (14)C19—N3—C22—C21−179.05 (15)
C10—C11—C12—C130.3 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1W—H2W1···N4i0.92 (3)1.99 (3)2.910 (2)175 (3)
O1W—H1W1···N1ii0.81 (3)2.16 (3)2.891 (2)151 (2)
C17—H17B···O1Wiii0.992.413.236 (2)141.
C19—H19B···O1Wiii0.992.563.327 (2)135.
C20—H20A···O2iv0.952.583.301 (2)133.

Symmetry codes: (i) −x+1, −y, −z+1; (ii) x+1/2, −y+1/2, z−1/2; (iii) x+1/2, −y+1/2, z+1/2; (iv) −x+1/2, y−1/2, −z+3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK5002).

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