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Acta Crystallogr Sect E Struct Rep Online. 2009 September 1; 65(Pt 9): o2211.
Published online 2009 August 22. doi:  10.1107/S160053680903267X
PMCID: PMC2969870

4,5-Bis(1H-imidazol-1-ylmeth­yl)acridine monohydrate

Abstract

In the title compound, C21H17N5·H2O, the dihedral angles between the acridine ring system and the imidazole rings are 78.8 (1) and 71.2 (1)°. The crystal packing is stabilized by O—H(...)N, C—H(...)O, C—H(...)π and π–π inter­actions [centroid–centroid separations = 3.732 (1) and 3.569 (1) Å].

Related literature

For the biological activity of acridines, see: Talacki et al. (1974 [triangle]); Achenson (1956 [triangle]); Prasad Krishna et al. (1984 [triangle]); Asthana et al. (1991 [triangle]). For their anti­protozoal activity, see: Karolak-Wojciechowska et al. (1996 [triangle]). For the ability of acridine to inter­calate between the base-pairs of DNA, see: Neidle (1979 [triangle]); Fan et al. (1997 [triangle]). For acridine compounds in the treatment of Alzheimer’s disease, see: Bandoli et al. (1994 [triangle]). For their toxicity, see: Di Giorgio et al. (2005 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o2211-scheme1.jpg

Experimental

Crystal data

  • C21H17N5·H2O
  • M r = 357.41
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2211-efi5.jpg
  • a = 14.3359 (6) Å
  • b = 6.9132 (3) Å
  • c = 17.7458 (8) Å
  • β = 92.895 (3)°
  • V = 1756.49 (13) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 293 K
  • 0.25 × 0.22 × 0.19 mm

Data collection

  • Bruker Kappa APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.978, T max = 0.984
  • 19520 measured reflections
  • 4286 independent reflections
  • 2652 reflections with I > 2σ(I)
  • R int = 0.036

Refinement

  • R[F 2 > 2σ(F 2)] = 0.046
  • wR(F 2) = 0.145
  • S = 1.06
  • 4286 reflections
  • 252 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.19 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT (Bruker, 2004 [triangle]); data reduction: SAINT; 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]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680903267X/bt5021sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680903267X/bt5021Isup2.hkl

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

Acknowledgments

ST and ASP thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the X-ray data collection.

supplementary crystallographic information

Comment

Acridines are found to have a wide range of biological activities, such as mutagenic, antitumour (Talacki et al., 1974), antibacterial (Achenson, 1956), antiamoebic (Prasad Krishna et al., 1984), hypersensitive, antiinflammatory and antiimplantation (Asthana et al., 1991) activities. A drug containing the acridine moiety has been found to possess antiprotozoal activity (Karolak-Wojciechowska et al., 1996). The ability of acridine to intercalate between the base-pairs of DNA is also well known (Neidle, 1979; Fan et al., 1997). Acridine compounds are considered to be efficient drugs for the treatment of Alzheimer's disease (Bandoli et al., 1994). Acridine derivatives have been shown to exert toxicity towards Plasmodium, Trypanosoma, and Leishmania parasites (Di Giorgio et al., 2005). The imidazole group have found a wide range of applications in coordination chemistry as ligands, in medicinal chemistry and materials science. Against this background, and in order to obtain detailed information on molecular conformations in the solid state, an X-ray study of the title compound has been carried out.

The two imidazole groups are almost parallel to each other, the dihedral angle between the mean planes being 39.5 (1)°; these planes are inclined at 78.9 (1)° and 71.2 (9)° with respect to the mean plane of the acridine system. The pseudo-torsion angle N2–C14···.C18–N4 [-145.8 (2)°], resulting in both imidazole group being approximately bisected by the plane of the acridine system. The acridine ring system and imidazole rings are essentially planar, with maximum deviations of 0.062 (3), 0.006 (2) and 0.001 (2) Å, for atoms C4, N3 and C19, respectively.

The crystal packing is stabilized by C–H···O, C–H···N, C–H···π (Table. 1) and π–π interactions with a Cg2···Cg2ii and a Cg4···Cg3iv separation of 3.732 (1)Å and 3.569 (1) Å, respectively (Fig.2; Cg2, Cg3 and Cg4 are the centroids of the N2/N3/C15–C17 imidazole ring, N1/C1/C6/C7/C8/C13 pyridine ring and C8–C13 benzene ring, respectively, symmetry code as in Fig. 2).

Experimental

To a solution of imidazole, in the presence of acetonitrile (50 ml) and NaOH solution (7.5 ml) was added and stirred for 10 minutes, then 4,5-bis(bromomethyl) acridine in the presence of acetonitrile(20 ml) was added at once and stirred at room temperature for 48hrs. After completion of reaction, the solvent was evaporated in vaccum and the residue was extracted with CHCl3(300 ml). Single crystals suitable for the X-ray diffraction were obtained by slow evaporation of a solution of the title compound in methanol at room temperature.

Refinement

H atoms of water were located is a difference fourier map, and were refined with distance restraints of O–H= 0.85 (3)Å. All other H atoms were fixed geometrically and allowed to ride on their parent atoms, with C–H = 0.93–0.98Å and with Uiso(H) = 1.2Ueq(C, N).

Figures

Fig. 1.
The structure of the title compound, showing the atom-numbering scheme and intramolecular hydrogen bond. Displacement ellipsoids are drawn at the 30% probability level.
Fig. 2.
C–H···O, O–H···N, C–H···π and π—π interactions (dotted lines) in the title compound. Cg denotes ring centroid. [Symmetry code: ...

Crystal data

C21H17N5·H2OF(000) = 752
Mr = 357.41Dx = 1.352 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4286 reflections
a = 14.3359 (6) Åθ = 1.8–28.1°
b = 6.9132 (3) ŵ = 0.09 mm1
c = 17.7458 (8) ÅT = 293 K
β = 92.895 (3)°Block, white crystalline
V = 1756.49 (13) Å30.25 × 0.22 × 0.19 mm
Z = 4

Data collection

Bruker Kappa APEXII CCD diffractometer4286 independent reflections
Radiation source: fine-focus sealed tube2652 reflections with I > 2σ(I)
graphiteRint = 0.036
ω scansθmax = 28.1°, θmin = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −19→19
Tmin = 0.978, Tmax = 0.984k = −9→8
19520 measured reflectionsl = −23→23

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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H atoms treated by a mixture of independent and constrained refinement
S = 1.06w = 1/[σ2(Fo2) + (0.0577P)2 + 0.3961P] where P = (Fo2 + 2Fc2)/3
4286 reflections(Δ/σ)max < 0.001
252 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = −0.20 e Å3

Special details

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)

xyzUiso*/Ueq
C10.31970 (12)0.7854 (2)−0.06027 (9)0.0394 (4)
C20.22370 (12)0.8010 (3)−0.08514 (10)0.0463 (4)
C30.20069 (15)0.8387 (3)−0.15855 (12)0.0618 (5)
H30.13820.8558−0.17370.074*
C40.26910 (17)0.8528 (4)−0.21250 (12)0.0715 (6)
H40.25130.8793−0.26260.086*
C50.35988 (16)0.8283 (3)−0.19224 (11)0.0609 (5)
H50.40410.8324−0.22880.073*
C60.38899 (13)0.7960 (3)−0.11539 (10)0.0446 (4)
C70.48111 (13)0.7751 (3)−0.09095 (10)0.0466 (4)
H70.52740.7779−0.12580.056*
C80.50554 (12)0.7500 (2)−0.01541 (10)0.0414 (4)
C90.59945 (12)0.7289 (3)0.01289 (12)0.0509 (5)
H90.64760.7313−0.02030.061*
C100.61933 (13)0.7056 (3)0.08691 (12)0.0570 (5)
H100.68110.69120.10480.068*
C110.54661 (13)0.7027 (3)0.13806 (11)0.0522 (5)
H110.56170.68570.18920.063*
C120.45576 (12)0.7241 (2)0.11476 (10)0.0412 (4)
C130.43189 (11)0.7464 (2)0.03633 (9)0.0374 (4)
C140.14924 (12)0.7687 (3)−0.03008 (11)0.0490 (4)
H14A0.16710.83180.01730.059*
H14B0.09120.8261−0.04960.059*
C150.10166 (15)0.4321 (3)−0.06850 (13)0.0663 (6)
H150.08650.4554−0.11930.080*
C160.09479 (17)0.2638 (3)−0.03245 (16)0.0750 (7)
H160.07270.1496−0.05450.090*
C180.38042 (13)0.7272 (3)0.17082 (10)0.0465 (4)
H18A0.32350.67370.14740.056*
H18B0.39920.64590.21350.056*
C190.30224 (12)1.0562 (3)0.16560 (11)0.0497 (5)
H190.26431.04150.12190.060*
C200.30963 (14)1.2133 (3)0.20991 (12)0.0584 (5)
H200.27651.32750.20130.070*
C210.40165 (14)1.0055 (3)0.25943 (10)0.0554 (5)
H210.44540.94430.29170.067*
N10.34184 (9)0.76245 (19)0.01343 (8)0.0385 (3)
N20.13497 (9)0.5626 (2)−0.01681 (8)0.0446 (4)
N30.12452 (15)0.2830 (3)0.04082 (14)0.0815 (6)
N40.36165 (9)0.9226 (2)0.19781 (8)0.0427 (4)
N50.37208 (13)1.1834 (3)0.26923 (10)0.0658 (5)
O10.04120 (12)0.0382 (3)0.15544 (11)0.0766 (5)
C170.14712 (15)0.4659 (4)0.04758 (12)0.0668 (6)
H170.16930.52210.09260.080*
H1A0.074 (2)0.096 (5)0.120 (2)0.138 (14)*
H1B0.066 (2)−0.070 (4)0.1662 (16)0.099 (11)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0481 (9)0.0282 (9)0.0424 (9)−0.0013 (7)0.0082 (7)0.0005 (7)
C20.0493 (10)0.0365 (10)0.0527 (11)−0.0003 (7)0.0009 (8)0.0019 (8)
C30.0616 (12)0.0634 (14)0.0593 (12)−0.0044 (10)−0.0090 (10)0.0072 (10)
C40.0830 (16)0.0837 (18)0.0469 (12)−0.0154 (13)−0.0069 (11)0.0117 (11)
C50.0765 (14)0.0628 (14)0.0444 (11)−0.0136 (11)0.0120 (10)0.0034 (9)
C60.0534 (10)0.0353 (10)0.0459 (10)−0.0060 (7)0.0119 (8)−0.0001 (7)
C70.0533 (10)0.0383 (10)0.0501 (10)−0.0047 (8)0.0206 (8)−0.0025 (8)
C80.0435 (9)0.0277 (9)0.0539 (10)−0.0006 (7)0.0115 (7)−0.0023 (7)
C90.0434 (9)0.0424 (11)0.0681 (13)0.0009 (8)0.0150 (8)−0.0049 (9)
C100.0434 (10)0.0515 (13)0.0756 (14)0.0053 (8)−0.0005 (9)−0.0052 (10)
C110.0560 (11)0.0450 (12)0.0548 (11)0.0033 (8)−0.0039 (9)−0.0028 (9)
C120.0468 (9)0.0302 (9)0.0469 (10)0.0003 (7)0.0044 (7)−0.0014 (7)
C130.0419 (9)0.0255 (8)0.0456 (9)0.0006 (6)0.0082 (7)−0.0013 (7)
C140.0443 (9)0.0406 (11)0.0623 (12)0.0026 (8)0.0027 (8)−0.0001 (9)
C150.0788 (14)0.0549 (14)0.0635 (13)−0.0027 (11)−0.0115 (11)−0.0049 (11)
C160.0743 (15)0.0424 (13)0.108 (2)−0.0039 (10)0.0035 (14)−0.0016 (13)
C180.0569 (10)0.0406 (11)0.0423 (9)−0.0052 (8)0.0057 (8)0.0042 (8)
C190.0440 (9)0.0541 (12)0.0519 (10)0.0030 (8)0.0122 (8)0.0075 (9)
C200.0586 (12)0.0549 (13)0.0642 (13)0.0068 (9)0.0276 (10)0.0016 (10)
C210.0568 (11)0.0655 (14)0.0445 (10)−0.0020 (10)0.0071 (8)−0.0060 (9)
N10.0420 (7)0.0303 (8)0.0440 (8)0.0003 (5)0.0090 (6)−0.0001 (6)
N20.0398 (7)0.0426 (9)0.0516 (9)0.0010 (6)0.0040 (6)0.0018 (7)
N30.0780 (13)0.0672 (15)0.0993 (17)−0.0087 (10)0.0051 (12)0.0298 (12)
N40.0448 (8)0.0454 (9)0.0388 (7)−0.0028 (6)0.0111 (6)0.0010 (6)
N50.0769 (12)0.0624 (13)0.0598 (11)−0.0014 (9)0.0203 (9)−0.0158 (9)
O10.0682 (10)0.0828 (14)0.0784 (12)0.0017 (10)0.0003 (9)0.0099 (10)
C170.0725 (14)0.0716 (17)0.0562 (12)−0.0135 (12)0.0012 (10)0.0141 (11)

Geometric parameters (Å, °)

C1—N11.340 (2)C14—N21.460 (2)
C1—C21.428 (2)C14—H14A0.9700
C1—C61.431 (2)C14—H14B0.9700
C2—C31.353 (3)C15—C161.334 (3)
C2—C141.500 (2)C15—N21.356 (3)
C3—C41.408 (3)C15—H150.9300
C3—H30.9300C16—N31.354 (3)
C4—C51.343 (3)C16—H160.9300
C4—H40.9300C18—N41.462 (2)
C5—C61.423 (3)C18—H18A0.9700
C5—H50.9300C18—H18B0.9700
C6—C71.377 (3)C19—C201.342 (3)
C7—C81.379 (3)C19—N41.362 (2)
C7—H70.9300C19—H190.9300
C8—C91.421 (3)C20—N51.363 (3)
C8—C131.434 (2)C20—H200.9300
C9—C101.340 (3)C21—N51.315 (3)
C9—H90.9300C21—N41.338 (2)
C10—C111.416 (3)C21—H210.9300
C10—H100.9300N2—C171.327 (2)
C11—C121.355 (2)N3—C171.310 (3)
C11—H110.9300O1—H1A0.91 (4)
C12—C131.425 (2)O1—H1B0.85 (3)
C12—C181.505 (2)C17—H170.9300
C13—N11.338 (2)
N1—C1—C2119.20 (15)N2—C14—H14A109.4
N1—C1—C6122.36 (15)C2—C14—H14A109.4
C2—C1—C6118.44 (16)N2—C14—H14B109.4
C3—C2—C1119.77 (17)C2—C14—H14B109.4
C3—C2—C14120.60 (17)H14A—C14—H14B108.0
C1—C2—C14119.60 (16)C16—C15—N2106.7 (2)
C2—C3—C4121.58 (19)C16—C15—H15126.6
C2—C3—H3119.2N2—C15—H15126.6
C4—C3—H3119.2C15—C16—N3110.4 (2)
C5—C4—C3120.52 (19)C15—C16—H16124.8
C5—C4—H4119.7N3—C16—H16124.8
C3—C4—H4119.7N4—C18—C12112.31 (14)
C4—C5—C6120.63 (19)N4—C18—H18A109.1
C4—C5—H5119.7C12—C18—H18A109.1
C6—C5—H5119.7N4—C18—H18B109.1
C7—C6—C5123.26 (17)C12—C18—H18B109.1
C7—C6—C1117.86 (16)H18A—C18—H18B107.9
C5—C6—C1118.88 (17)C20—C19—N4105.90 (18)
C6—C7—C8120.78 (15)C20—C19—H19127.1
C6—C7—H7119.6N4—C19—H19127.1
C8—C7—H7119.6C19—C20—N5111.03 (19)
C7—C8—C9123.10 (16)C19—C20—H20124.5
C7—C8—C13117.74 (15)N5—C20—H20124.5
C9—C8—C13119.16 (16)N5—C21—N4112.40 (19)
C10—C9—C8120.65 (17)N5—C21—H21123.8
C10—C9—H9119.7N4—C21—H21123.8
C8—C9—H9119.7C13—N1—C1118.91 (14)
C9—C10—C11120.20 (18)C17—N2—C15105.89 (18)
C9—C10—H10119.9C17—N2—C14128.06 (17)
C11—C10—H10119.9C15—N2—C14125.97 (17)
C12—C11—C10122.02 (18)C17—N3—C16104.28 (19)
C12—C11—H11119.0C21—N4—C19106.58 (17)
C10—C11—H11119.0C21—N4—C18125.81 (16)
C11—C12—C13119.33 (16)C19—N4—C18127.60 (15)
C11—C12—C18120.72 (16)C21—N5—C20104.10 (17)
C13—C12—C18119.95 (15)H1A—O1—H1B109 (3)
N1—C13—C12119.07 (14)N3—C17—N2112.7 (2)
N1—C13—C8122.30 (15)N3—C17—H17123.6
C12—C13—C8118.62 (15)N2—C17—H17123.6
N2—C14—C2111.13 (14)
N1—C1—C2—C3175.05 (17)C9—C8—C13—N1−178.93 (15)
C6—C1—C2—C3−4.7 (3)C7—C8—C13—C12−178.90 (15)
N1—C1—C2—C14−7.0 (2)C9—C8—C13—C120.8 (2)
C6—C1—C2—C14173.28 (16)C3—C2—C14—N299.4 (2)
C1—C2—C3—C43.6 (3)C1—C2—C14—N2−78.6 (2)
C14—C2—C3—C4−174.4 (2)N2—C15—C16—N3−1.1 (3)
C2—C3—C4—C50.2 (4)C11—C12—C18—N489.8 (2)
C3—C4—C5—C6−2.8 (4)C13—C12—C18—N4−89.38 (19)
C4—C5—C6—C7−178.2 (2)N4—C19—C20—N50.1 (2)
C4—C5—C6—C11.5 (3)C12—C13—N1—C1179.31 (14)
N1—C1—C6—C72.2 (2)C8—C13—N1—C1−1.0 (2)
C2—C1—C6—C7−178.12 (16)C2—C1—N1—C13179.48 (15)
N1—C1—C6—C5−177.52 (17)C6—C1—N1—C13−0.8 (2)
C2—C1—C6—C52.2 (2)C16—C15—N2—C170.5 (2)
C5—C6—C7—C8177.98 (18)C16—C15—N2—C14−176.70 (17)
C1—C6—C7—C8−1.7 (3)C2—C14—N2—C17118.2 (2)
C6—C7—C8—C9−179.63 (16)C2—C14—N2—C15−65.3 (2)
C6—C7—C8—C130.0 (2)C15—C16—N3—C171.3 (3)
C7—C8—C9—C10179.76 (18)N5—C21—N4—C190.1 (2)
C13—C8—C9—C100.1 (3)N5—C21—N4—C18179.16 (15)
C8—C9—C10—C11−0.3 (3)C20—C19—N4—C21−0.08 (19)
C9—C10—C11—C12−0.4 (3)C20—C19—N4—C18−179.16 (15)
C10—C11—C12—C131.3 (3)C12—C18—N4—C21−92.4 (2)
C10—C11—C12—C18−177.90 (18)C12—C18—N4—C1986.5 (2)
C11—C12—C13—N1178.27 (15)N4—C21—N5—C200.0 (2)
C18—C12—C13—N1−2.6 (2)C19—C20—N5—C210.0 (2)
C11—C12—C13—C8−1.4 (2)C16—N3—C17—N2−1.0 (3)
C18—C12—C13—C8177.73 (15)C15—N2—C17—N30.4 (3)
C7—C8—C13—N11.4 (2)C14—N2—C17—N3177.43 (17)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C18—H18B···O1i0.972.553.482 (3)162
O1—H1A···N30.90 (3)2.07 (3)2.945 (3)166 (3)
O1—H1B···N5ii0.85 (3)2.21 (3)3.030 (3)162 (3)
C7—H7···Cg1iii0.932.693.577 (2)159
C20—H20···Cg1iv0.932.903.648 (2)139

Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) −x+1/2, y−3/2, −z+1/2; (iii) −x+1, −y+2, −z; (iv) −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: BT5021).

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