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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 4| April 2014| Page o439
doi:10.1107/S1600536814005327

6,8-Di­bromo-4-oxo-4H-chromene-3-carbaldehyde

Yoshinobu Ishikawaa*

aSchool of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
*Correspondence e-mail: ishi206@u-shizuoka-ken.ac.jp

(Received 6 February 2014; accepted 7 March 2014; online 15 March 2014)

In the title compound, C10H4Br2O3, the atoms of the 6,8-di­bromo­chromone unit are essentially coplanar [largest deviation from the mean planes = 0.1109 (3) Å] and the formyl group is twisted slightly with respect to the attached ring [C—C—C—O torsion angles = 11.5 (4) and −168.9 (3)°]. In the crystal, mol­ecules are linked to each other through halogen bonds [Br⋯O = 3.118 (2) Å, C—Br⋯O = 162.37 (8) and C=O⋯Br = 140.20 (15)°]. The molecules are further assembled via π–π stacking interactions [centroid–centroid distance = 3.850 (2) Å].

CCDC reference: 990678

Related literature

For the biological activity of the title compound, see: Kawase et al. (2007[Kawase, M., Tanaka, T., Kan, H., Tani, S., Nakashima, H. & Sakagami, H. (2007). In Vivo, 21, 829-834.]). For its use as a starting material for the synthesis of alkaline phosphatase inhibitorsrelated literature, see: al-Rashida et al. (2013[al-Rashida, M., Raza, R., Abbas, G., Shah, M. S., Kostakis, G. E., Lecka, J., Sévigny, J., Muddassar, M., Papatriantafyllopoulou, C., & Iqbal, J. (2013). Eur. J. Med. Chem. 66, 438-449.]). For a related structure, see: Ishikawa & Motohashi (2013[Ishikawa, Y. & Motohashi, Y. (2013). Acta Cryst. E69, o1416.]). For halogen bonding, see: Auffinger et al. (2004[Auffinger, P., Hays, F. A., Westhof, E. & Ho, P. S. (2004). Proc. Natl Acad. Sci. USA, 101, 16789-16794.]); Metrangolo et al. (2005[Metrangolo, P., Neukirch, H., Pilati, T. & Resnati, G. (2005). Acc. Chem. Res. 38, 386-395.]); Wilcken et al. (2013[Wilcken, R., Zimmermann, M. O., Lange, A., Joerger, A. C. & Boeckler, F. M. (2013). J. Med. Chem. 56, 1363-1388.]); Sirimulla et al. (2013[Sirimulla, S., Bailey, J. B., Vegesna, R. & Narayan, M. (2013). J. Chem. Inf. Model. 53, 2781-2791.]).

[Scheme 1]

Experimental

Crystal data

  • C10H4Br2O3

  • Mr = 331.95

  • Monoclinic, P 21 /c

  • a = 11.910 (4) Å

  • b = 3.8500 (12) Å

  • c = 20.817 (6) Å

  • β = 95.69 (3)°

  • V = 949.8 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 8.54 mm−1

  • T = 100 K

  • 0.42 × 0.25 × 0.23 mm
Data collection

  • Rigaku AFC-7R diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.086, Tmax = 0.140

  • 2871 measured reflections

  • 2163 independent reflections

  • 1937 reflections with F2 > 2σ(F2)

  • Rint = 0.010

  • 3 standard reflections every 150 reflections intensity decay: −0.1%
Refinement

  • R[F2 > 2σ(F2)] = 0.019

  • wR(F2) = 0.045

  • S = 1.06

  • 2163 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.46 e Å−3

Data collection: WinAFC (Rigaku, 1999[Rigaku (1999). WinAFC Diffractometer Control Software. Rigaku Corporation, Tokyo, Japan.]); cell refinement: WinAFC; data reduction: WinAFC; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: CrystalStructure (Rigaku, 2010[Rigaku (2010). CrystalStructure. Rigaku Corporation, Tokyo, Japan.]); software used to prepare material for publication: CrystalStructure.

Supporting information

CCDC reference: 990678

Crystal structure: contains datablocks General, I. DOI: 10.1107/S1600536814005327/rn2123sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814005327/rn2123Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814005327/rn2123Isup3.cml

checkCIF report


Comment top

The title compound shows tumor cell-cytotoxic, anti-HIV, anti-Helicobacter pylori, and urease inhibitory activities (Kawase et al. 2007). In addition, it is used as a starting material for the synthesis of alkaline phosphatase inhibitors (al-Rashida et al. 2013).

The atoms of 6,8-dibromo-chromone ring in the title compound is essentially coplanar, and the largest deviations is 0.1109 (3) Å for Br2. The formyl group is slightly twisted with respect to the attached ring [C1–C2–C10–O3 = 11.5 (4)° and C3–C2–C10–O3 = -168.9 (3)°].

In the crystal, the molecules are linked to each other through intermolecular interactions of the Br2 atom with the O3 atom of the formyl group [Br2···O3; 3.118 (2) Å, C7–Br2···O3i = 162.37 (8)°, Br2···Oi–C10i = 140.20 (15)° (i): -x + 2, -y + 1, -z + 1], as shown in Fig. 1. The short contact and the geometry of the Br···O interactions come within the range of halogen bonding (Auffinger et al. 2004). The similar geometry is found in the crystal structure of 6,8-dichloro-4-oxochromene-3-carbaldehyde (Ishikawa et al. 2013).

Halogen bonds have been found to occur in organic, inorganic, and biological systems, and have recently attracted much attention in medicinal chemistry, chemical biology, and supramolecular chemistry (Auffinger et al. 2004, Metrangolo et al. 2005, Wilcken et al. 2013, Sirimulla et al. 2013). Our analysis suggests that the strong inhibitory activity of the title compound against urease might be attributable to the halogen bond observed in the crystal, because 3-formylchromones without any halogen atom at the 8-position in the literature do not show the urease inhibitory activity (Kawase et al. 2007).

Related literature top

For the biological activity of the title compound, see: Kawase et al. (2007). For its use as a starting material for the synthesis of alkaline phosphatase inhibitorsrelated literature, see: al-Rashida et al. (2013). For a related structure, see: Ishikawa & Motohashi (2013). For halogen bonding, see: Auffinger et al. (2004); Metrangolo et al. (2005); Wilcken et al. (2013); Sirimulla et al. (2013).

Experimental top

Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a 2-butanone solution of commercially available title compound at room temperature.

Refinement top

The C(sp2)-bound hydrogen atoms were placed in geometrical positions [C—H 0.95 Å, Uiso(H) = 1.2Ueq(C)], and refined using a riding model.

Computing details top

Data collection: WinAFC (Rigaku, 1999); cell refinement: WinAFC (Rigaku, 1999); data reduction: WinAFC (Rigaku, 1999); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku, 2010); software used to prepare material for publication: CrystalStructure (Rigaku, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level. Hydrogen atoms are shown as small spheres of arbitrary radius. The intermolecular interaction of the title compound is represented as dashed lines for Br···O.
6,8-Dibromo-4-oxo-4H-chromene-3-carbaldehyde top
Crystal data top
C10H4Br2O3F(000) = 632.00
Mr = 331.95Dx = 2.321 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 11.910 (4) Åθ = 15.0–17.3°
b = 3.8500 (12) ŵ = 8.54 mm−1
c = 20.817 (6) ÅT = 100 K
β = 95.69 (3)°Block, colorless
V = 949.8 (5) Å30.42 × 0.25 × 0.23 mm
Z = 4
Data collection top
Rigaku AFC-7R
diffractometer		Rint = 0.010
ω scansθmax = 27.5°
Absorption correction: ψ scan
(North et al., 1968)		h = −15→15
Tmin = 0.086, Tmax = 0.140k = −2→4
2871 measured reflectionsl = −14→26
2163 independent reflections3 standard reflections every 150 reflections
1937 reflections with F2 > 2σ(F2) intensity decay: −0.1%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.019Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.045H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0209P)2 + 0.9331P]
where P = (Fo2 + 2Fc2)/3
2163 reflections(Δ/σ)max = 0.002
136 parametersΔρmax = 0.37 e Å−3
0 restraintsΔρmin = −0.46 e Å−3
Primary atom site location: structure-invariant direct methods
Crystal data top
C10H4Br2O3V = 949.8 (5) Å3
Mr = 331.95Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.910 (4) ŵ = 8.54 mm−1
b = 3.8500 (12) ÅT = 100 K
c = 20.817 (6) Å0.42 × 0.25 × 0.23 mm
β = 95.69 (3)°
Data collection top
Rigaku AFC-7R
diffractometer		1937 reflections with F2 > 2σ(F2)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.010
Tmin = 0.086, Tmax = 0.1403 standard reflections every 150 reflections
2871 measured reflections intensity decay: −0.1%
2163 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0190 restraints
wR(F2) = 0.045H-atom parameters constrained
S = 1.06Δρmax = 0.37 e Å−3
2163 reflectionsΔρmin = −0.46 e Å−3
136 parameters
Special details top

Refinement. Refinement was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.573035 (18)0.93086 (6)0.699129 (10)0.01429 (7)
Br20.985432 (18)0.27016 (6)0.660364 (10)0.01402 (6)
O10.88801 (13)0.2982 (5)0.52224 (7)0.0135 (4)
O20.59071 (14)0.7059 (5)0.43970 (8)0.0183 (4)
O30.78264 (15)0.1122 (6)0.32871 (8)0.0230 (4)
C10.85463 (19)0.2641 (7)0.45870 (10)0.0137 (5)
C20.75650 (19)0.3792 (7)0.42904 (10)0.0138 (5)
C30.67683 (19)0.5722 (7)0.46469 (10)0.0132 (5)
C40.63812 (18)0.7387 (6)0.57688 (10)0.0125 (5)
C50.67063 (18)0.7382 (7)0.64209 (10)0.0122 (5)
C60.77314 (18)0.5989 (7)0.66820 (10)0.0129 (5)
C70.84520 (18)0.4570 (7)0.62724 (10)0.0123 (5)
C80.71085 (18)0.5882 (7)0.53541 (10)0.0119 (5)
C90.81363 (18)0.4500 (6)0.56088 (10)0.0111 (5)
C100.7291 (2)0.3114 (7)0.35894 (11)0.0173 (5)
H10.90460.14920.43290.0165*
H40.56820.83810.56020.0149*
H60.79320.60160.71350.0155*
H100.66680.42960.33680.0208*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.01503 (11)0.01571 (12)0.01299 (11)0.00054 (9)0.00562 (8)−0.00072 (9)
Br20.01206 (11)0.01685 (12)0.01260 (11)0.00133 (9)−0.00153 (8)0.00018 (9)
O10.0109 (8)0.0193 (9)0.0102 (7)0.0017 (7)0.0008 (6)−0.0015 (7)
O20.0151 (8)0.0233 (10)0.0159 (8)0.0032 (8)−0.0015 (7)0.0023 (8)
O30.0206 (9)0.0327 (11)0.0157 (8)0.0031 (9)0.0015 (7)−0.0066 (8)
C10.0151 (11)0.0162 (12)0.0099 (10)−0.0017 (10)0.0013 (8)−0.0029 (9)
C20.0142 (11)0.0145 (12)0.0128 (11)−0.0025 (10)0.0013 (9)−0.0005 (9)
C30.0142 (11)0.0137 (12)0.0117 (10)−0.0038 (10)0.0013 (8)0.0008 (9)
C40.0107 (10)0.0117 (12)0.0148 (11)−0.0015 (9)0.0003 (8)0.0009 (9)
C50.0121 (11)0.0114 (12)0.0141 (10)−0.0025 (10)0.0072 (8)−0.0014 (9)
C60.0150 (11)0.0135 (12)0.0103 (10)−0.0022 (10)0.0013 (8)0.0006 (9)
C70.0109 (10)0.0123 (12)0.0136 (11)−0.0007 (9)−0.0004 (8)0.0012 (9)
C80.0114 (10)0.0125 (12)0.0119 (10)−0.0029 (10)0.0017 (8)0.0012 (9)
C90.0108 (10)0.0110 (11)0.0122 (10)−0.0008 (9)0.0041 (8)0.0002 (9)
C100.0157 (11)0.0241 (14)0.0117 (11)−0.0008 (11)−0.0006 (9)−0.0006 (10)
Geometric parameters (Å, º) top
Br1—C51.893 (3)C4—C51.374 (3)
Br2—C71.885 (3)C4—C81.407 (4)
O1—C11.349 (3)C5—C61.394 (3)
O1—C91.384 (3)C6—C71.381 (4)
O2—C31.217 (3)C7—C91.395 (3)
O3—C101.213 (4)C8—C91.391 (3)
C1—C21.342 (3)C1—H10.950
C2—C31.464 (4)C4—H40.950
C2—C101.486 (3)C6—H60.950
C3—C81.489 (3)C10—H100.950
Br2···O12.9940 (17)C10···O2v3.395 (4)
O1···C32.877 (3)C10···O3iii3.223 (4)
O2···C13.561 (3)Br1···H42.9089
O2···C42.858 (3)Br1···H62.9009
O2···C102.898 (4)Br2···H62.9323
O3···C12.818 (3)O2···H42.5993
C1···C73.599 (4)O2···H102.6314
C1···C82.753 (4)O3···H12.4918
C2···C92.775 (3)C1···H103.2748
C4···C72.801 (3)C3···H13.2875
C5···C92.750 (4)C3···H42.6802
C6···C82.790 (3)C3···H102.7091
Br1···Br1i3.4567 (8)C4···H63.2769
Br1···Br1ii3.4567 (8)C6···H43.2818
Br1···C5iii3.563 (3)C9···H13.1918
Br2···O3iv3.118 (2)C9···H43.2814
Br2···C7v3.583 (3)C9···H63.2634
O1···O1vi3.298 (3)C10···H12.5478
O1···C1vi3.486 (3)H1···H103.4736
O1···C8v3.481 (3)Br1···H10vii3.1969
O1···C9v3.498 (3)Br1···H10xi3.0191
O2···C2iii3.280 (3)Br2···H1iv2.9314
O2···C3iii3.513 (4)Br2···H1vi3.3140
O2···C4vii3.208 (3)Br2···H6xii3.5908
O2···C4viii3.455 (3)O1···H1iv3.0794
O2···C10iii3.395 (4)O1···H1vi3.3226
O3···Br2iv3.118 (2)O2···H4vii2.8234
O3···C2v3.543 (4)O2···H4viii2.5820
O3···C6ix3.430 (3)O3···H6ix2.5500
O3···C10v3.223 (4)O3···H10v2.9808
C1···O1vi3.486 (3)C1···H1iii3.5101
C1···C3v3.413 (4)C2···H1iii3.4467
C1···C8v3.577 (4)C3···H4vii3.3142
C2···O2v3.280 (3)C4···H4v3.5744
C2···O3iii3.543 (4)C8···H4v3.4152
C2···C3v3.353 (4)C10···H6ix3.5682
C3···O2v3.513 (4)C10···H10v3.4959
C3···C1iii3.413 (4)H1···Br2iv2.9314
C3···C2iii3.353 (4)H1···Br2vi3.3140
C4···O2vii3.208 (3)H1···O1iv3.0794
C4···O2viii3.455 (3)H1···O1vi3.3226
C4···C8iii3.513 (4)H1···C1v3.5101
C4···C9iii3.481 (4)H1···C2v3.4467
C5···Br1v3.563 (3)H4···O2vii2.8234
C5···C6iii3.555 (4)H4···O2viii2.5820
C5···C7iii3.493 (4)H4···C3vii3.3142
C6···O3x3.430 (3)H4···C4iii3.5744
C6···C5v3.555 (4)H4···C8iii3.4152
C6···C7iii3.539 (4)H4···H4viii3.1095
C7···Br2iii3.583 (3)H6···Br2xiii3.5908
C7···C5v3.493 (4)H6···O3x2.5500
C7···C6v3.539 (4)H6···C10x3.5682
C8···O1iii3.481 (3)H6···H10xi3.5884
C8···C1iii3.577 (4)H10···Br1vii3.1969
C8···C4v3.513 (4)H10···Br1xiv3.0191
C8···C9iii3.558 (4)H10···O3iii2.9808
C9···O1iii3.498 (3)H10···C10iii3.4959
C9···C4v3.481 (4)H10···H6xiv3.5884
C9···C8v3.558 (4)
C1—O1—C9117.88 (17)C3—C8—C4119.99 (19)
O1—C1—C2125.3 (3)C3—C8—C9120.3 (2)
C1—C2—C3120.9 (2)C4—C8—C9119.73 (19)
C1—C2—C10119.3 (3)O1—C9—C7117.29 (19)
C3—C2—C10119.8 (2)O1—C9—C8122.01 (19)
O2—C3—C2124.0 (2)C7—C9—C8120.7 (2)
O2—C3—C8122.7 (3)O3—C10—C2123.0 (3)
C2—C3—C8113.31 (19)O1—C1—H1117.367
C5—C4—C8118.4 (2)C2—C1—H1117.366
Br1—C5—C4119.25 (17)C5—C4—H4120.820
Br1—C5—C6118.34 (16)C8—C4—H4120.803
C4—C5—C6122.4 (2)C5—C6—H6120.481
C5—C6—C7119.05 (19)C7—C6—H6120.472
Br2—C7—C6120.49 (16)O3—C10—H10118.496
Br2—C7—C9119.78 (17)C2—C10—H10118.482
C6—C7—C9119.7 (2)
C1—O1—C9—C7174.68 (18)C8—C4—C5—Br1−178.77 (18)
C1—O1—C9—C8−4.8 (3)C8—C4—C5—C60.9 (4)
C9—O1—C1—C23.1 (4)H4—C4—C5—Br11.2
C9—O1—C1—H1−176.9H4—C4—C5—C6−179.1
O1—C1—C2—C32.7 (4)H4—C4—C8—C3−2.2
O1—C1—C2—C10−177.74 (19)H4—C4—C8—C9178.8
H1—C1—C2—C3−177.3Br1—C5—C6—C7179.91 (14)
H1—C1—C2—C102.3Br1—C5—C6—H6−0.1
C1—C2—C3—O2174.2 (3)C4—C5—C6—C70.3 (4)
C1—C2—C3—C8−6.2 (4)C4—C5—C6—H6−179.8
C1—C2—C10—O311.5 (4)C5—C6—C7—Br2179.31 (18)
C1—C2—C10—H10−168.5C5—C6—C7—C9−1.1 (4)
C3—C2—C10—O3−168.9 (3)H6—C6—C7—Br2−0.7
C3—C2—C10—H1011.1H6—C6—C7—C9178.9
C10—C2—C3—O2−5.4 (4)Br2—C7—C9—O10.9 (3)
C10—C2—C3—C8174.23 (19)Br2—C7—C9—C8−179.62 (14)
O2—C3—C8—C45.1 (4)C6—C7—C9—O1−178.7 (2)
O2—C3—C8—C9−175.9 (2)C6—C7—C9—C80.8 (4)
C2—C3—C8—C4−174.51 (19)C3—C8—C9—O10.8 (4)
C2—C3—C8—C94.5 (3)C3—C8—C9—C7−178.61 (19)
C5—C4—C8—C3177.82 (19)C4—C8—C9—O1179.8 (2)
C5—C4—C8—C9−1.2 (4)C4—C8—C9—C70.4 (4)
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+1, y+1/2, −z+3/2; (iii) x, y+1, z; (iv) −x+2, −y, −z+1; (v) x, y−1, z; (vi) −x+2, −y+1, −z+1; (vii) −x+1, −y+1, −z+1; (viii) −x+1, −y+2, −z+1; (ix) x, −y+1/2, z−1/2; (x) x, −y+1/2, z+1/2; (xi) x, −y+3/2, z+1/2; (xii) −x+2, y−1/2, −z+3/2; (xiii) −x+2, y+1/2, −z+3/2; (xiv) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formulaC10H4Br2O3
Mr331.95
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)11.910 (4), 3.8500 (12), 20.817 (6)
β (°) 95.69 (3)
V (Å3)949.8 (5)
Z4
Radiation typeMo Kα
µ (mm−1)8.54
Crystal size (mm)0.42 × 0.25 × 0.23
Data collection
DiffractometerRigaku AFC-7R
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.086, 0.140
No. of measured, independent and
observed [F2 > 2σ(F2)] reflections		2871, 2163, 1937
Rint0.010
(sin θ/λ)max (Å−1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.019, 0.045, 1.06
No. of reflections2163
No. of parameters136
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.37, −0.46

Computer programs: WinAFC (Rigaku, 1999), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), CrystalStructure (Rigaku, 2010).

 

Acknowledgements

We acknowledge University of Shizuoka for instrumental support.

References

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ISSN: 2056-9890
Volume 70| Part 4| April 2014| Page o439
doi:10.1107/S1600536814005327
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