organic compounds
5-(Prop-2-yn-1-yl)-5H-dibenzo[b,f]azepine: orthorhombic polymorph
aDepartment of Physics, Faculty of Science, An Najah National University, Nabtus West Bank, Palestine, bDepartment of Studies in Physics, Manasagangotri, University of Mysore, Mysore 570 006, India, and cDepartment of Studies in Chemistry, Manasagangotri, University of Mysore, Mysore 570 006, India
*Correspondence e-mail: lokanath@physics.uni-mysore.ac.in
In the title orthorhombic polymorph (space group Iba2), C17H13N, the dihedral angle between the benzene rings is 55.99 (10)° and the azepine ring adopts a boat conformation. In the crystal, molecules are linked by C—H⋯π contacts. The previously-reported polymorph [Yousuf et al. (2012). Acta Cryst. E68, o1101] crystallizes in the monoclinic system (space group P21/c) with two molecules in the asymmetric unit.
Related literature
For the previously-reported monoclinic polymorph, see: Yousuf et al. (2012). For biochemical background, see: Sadashiva et al. (2005).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536812048908/hb6998sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812048908/hb6998Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536812048908/hb6998Isup3.cml
5H-dibenzo[b,f]azepine (1, 0.0026 mol) was taken in a mixture of toluene and water in the ratio 1:1,was added sodium hydroxide (0.026 mol) followed by tetra-n-butylammonium bromide (TBAB) (0.00286 mol) at room temperature. After 15 minutes, propargyl bromide was added (0.00286 mol) at room temperature. Then, the resulting reaction mixture was heated at 60°C for 5 h. After completion of reaction (monitored by TLC), the reaction mixture was diluted with water (50 ml). The aqueous layer was extracted with ethyl acetate (3 × 20 ml), the combined ethyl acetate layer was washed with 0.1 N hydrochloric acid (2 × 25 ml), followed by brine solution (2 × 25 ml). Then, the organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford crude 2, which was purified by
over silica gel (60–120 mesh) using Hexane: Ethyl acetate mixture in 9.5:0.5 ratios as The pure compound 2 was crystallized in ethyl acetate and hexane to obtain yellow blocks.1H NMR (DMSO-d6, 300 MHz): δ 7.33 (t, J=7.2 Hz, 2H), 7.13 (t, J=8.7 Hz, 4H), 7.02 (t, J=7.2 Hz, 2H), 6.75 (s, 2H), 4.51 (d, J=1.8 Hz, 2H), 3.08 (s, 1H).
MS (M++1): 232. Melting point (°C): 90 (Uncorrected)
In the absence of significant
effects Friedel pairs were merged. All the hydrogen atoms of the compound are fixed geometrically (C—H= 0.93–0.97 Å) and allowed to ride on their parent atoms. The poorly fitted reflections (2 0 0) and (1 1 0) were omitted during refinement.As part of our studies of new derivatives useful for tailoring of biologically active 5-membered heterocyclic rings such as 3,5-disubstituted isoxazole (Sadashiva et al., 2005), we now describe the title compound.
In the title molecule, C17 H13 N (Fig. 1.), benzene rings fused to azepine rings are nearly planar and its geometry is similar to 5-(Prop-2-ynyl)-5H-dibenzo[b,f]azepine (Yousuf et al., 2012). The dihedral angle between the benzene rings is 55.99 (10)° which is almost equal and large compared to the two molecules repectively for the first polymorph.
Seven-membered azepine ring adopts a boat conformation as indicated by the puckering parameters Q2 = 0.7126 (18) Å, Q3 = 0.2154 (17) Å, φ2 = 177.93 (15) °, φ3 = 178.1 (5) °, and the total puckering amplitude QT = 0.7444 (17) Å. The title molecule adopts butterfly shape which may be essential for inhibition pocket which is similar to the reported polymorph (Yousuf et al., 2012).
The packing of the title molecules is as shown (Fig. 2.) and features short C—H···π contacts (Table 1).
For the previously-reported monoclinic polymorph, see: Yousuf et al. (2012). For biochemical background, see: Sadashiva et al. (2005).
Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell
CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C17H13N | F(000) = 976 |
Mr = 231.28 | Dx = 1.234 Mg m−3 |
Orthorhombic, Iba2 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: I 2 -2c | Cell parameters from 1199 reflections |
a = 16.2444 (6) Å | θ = 3.2–25.0° |
b = 21.1700 (6) Å | µ = 0.07 mm−1 |
c = 7.2399 (2) Å | T = 103 K |
V = 2489.76 (13) Å3 | Block, yellow |
Z = 8 | 0.35 × 0.30 × 0.25 mm |
Oxford Diffraction Xcalibur Eos diffractometer | 1132 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.027 |
Graphite monochromator | θmax = 25.0°, θmin = 3.2° |
Detector resolution: 16.0839 pixels mm-1 | h = −19→19 |
ω scans | k = −25→25 |
10081 measured reflections | l = −8→8 |
1199 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.026 | H-atom parameters constrained |
wR(F2) = 0.067 | w = 1/[σ2(Fo2) + (0.0354P)2 + 0.3725P] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max < 0.001 |
1199 reflections | Δρmax = 0.08 e Å−3 |
164 parameters | Δρmin = −0.10 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), FC*=KFC[1+0.001XFC2Λ3/SIN(2Θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0046 (6) |
C17H13N | V = 2489.76 (13) Å3 |
Mr = 231.28 | Z = 8 |
Orthorhombic, Iba2 | Mo Kα radiation |
a = 16.2444 (6) Å | µ = 0.07 mm−1 |
b = 21.1700 (6) Å | T = 103 K |
c = 7.2399 (2) Å | 0.35 × 0.30 × 0.25 mm |
Oxford Diffraction Xcalibur Eos diffractometer | 1132 reflections with I > 2σ(I) |
10081 measured reflections | Rint = 0.027 |
1199 independent reflections |
R[F2 > 2σ(F2)] = 0.026 | 1 restraint |
wR(F2) = 0.067 | H-atom parameters constrained |
S = 1.09 | Δρmax = 0.08 e Å−3 |
1199 reflections | Δρmin = −0.10 e Å−3 |
164 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.23053 (8) | 0.36797 (6) | 0.6618 (2) | 0.0409 (4) | |
C2 | 0.31311 (10) | 0.36894 (7) | 0.5957 (3) | 0.0414 (5) | |
C3 | 0.34432 (10) | 0.42627 (8) | 0.5292 (3) | 0.0492 (6) | |
C4 | 0.29519 (12) | 0.48379 (8) | 0.5170 (3) | 0.0560 (6) | |
C5 | 0.21579 (11) | 0.48775 (7) | 0.4806 (3) | 0.0538 (6) | |
C6 | 0.15967 (10) | 0.43569 (8) | 0.4423 (3) | 0.0450 (5) | |
C7 | 0.16937 (9) | 0.37583 (7) | 0.5219 (2) | 0.0399 (5) | |
C8 | 0.11790 (10) | 0.32691 (8) | 0.4686 (3) | 0.0483 (6) | |
C9 | 0.05556 (11) | 0.33719 (9) | 0.3419 (3) | 0.0592 (7) | |
C10 | 0.04355 (11) | 0.39633 (10) | 0.2688 (3) | 0.0635 (7) | |
C11 | 0.09515 (11) | 0.44467 (9) | 0.3192 (3) | 0.0571 (6) | |
C12 | 0.36307 (11) | 0.31589 (9) | 0.5992 (3) | 0.0532 (6) | |
C13 | 0.44347 (12) | 0.31917 (11) | 0.5374 (3) | 0.0705 (8) | |
C14 | 0.47460 (12) | 0.37508 (13) | 0.4711 (4) | 0.0791 (9) | |
C15 | 0.42559 (12) | 0.42769 (11) | 0.4679 (4) | 0.0691 (8) | |
C16 | 0.21109 (11) | 0.32276 (8) | 0.8082 (3) | 0.0491 (6) | |
C17 | 0.26199 (11) | 0.33371 (8) | 0.9703 (3) | 0.0474 (6) | |
C18 | 0.30303 (14) | 0.34250 (9) | 1.1020 (3) | 0.0616 (7) | |
H4 | 0.32340 | 0.52250 | 0.53740 | 0.0670* | |
H5 | 0.19270 | 0.52900 | 0.47920 | 0.0650* | |
H8 | 0.12550 | 0.28600 | 0.51950 | 0.0580* | |
H9 | 0.02100 | 0.30320 | 0.30540 | 0.0710* | |
H10 | −0.00010 | 0.40370 | 0.18410 | 0.0760* | |
H11 | 0.08650 | 0.48550 | 0.26830 | 0.0690* | |
H12 | 0.34190 | 0.27700 | 0.64430 | 0.0640* | |
H13 | 0.47730 | 0.28260 | 0.54070 | 0.0850* | |
H14 | 0.52970 | 0.37720 | 0.42790 | 0.0950* | |
H15 | 0.44760 | 0.46630 | 0.42260 | 0.0830* | |
H16A | 0.15230 | 0.32680 | 0.84240 | 0.0590* | |
H16B | 0.22030 | 0.27930 | 0.76240 | 0.0590* | |
H18 | 0.33610 | 0.34960 | 1.20820 | 0.0740* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0432 (7) | 0.0429 (7) | 0.0367 (8) | −0.0037 (6) | 0.0005 (6) | 0.0061 (6) |
C2 | 0.0424 (8) | 0.0505 (9) | 0.0314 (8) | −0.0034 (8) | −0.0036 (8) | −0.0045 (7) |
C3 | 0.0494 (9) | 0.0594 (10) | 0.0389 (10) | −0.0153 (8) | −0.0019 (8) | −0.0043 (8) |
C4 | 0.0762 (12) | 0.0439 (10) | 0.0479 (11) | −0.0187 (8) | 0.0020 (10) | −0.0015 (8) |
C5 | 0.0747 (11) | 0.0393 (9) | 0.0474 (11) | 0.0003 (8) | 0.0066 (11) | 0.0039 (8) |
C6 | 0.0506 (9) | 0.0464 (8) | 0.0380 (9) | 0.0061 (7) | 0.0079 (8) | 0.0023 (8) |
C7 | 0.0385 (8) | 0.0449 (8) | 0.0362 (9) | 0.0031 (7) | 0.0050 (7) | −0.0001 (7) |
C8 | 0.0464 (9) | 0.0486 (9) | 0.0498 (11) | −0.0009 (8) | −0.0006 (9) | −0.0001 (8) |
C9 | 0.0498 (10) | 0.0693 (12) | 0.0584 (13) | −0.0044 (9) | −0.0072 (10) | −0.0051 (10) |
C10 | 0.0506 (10) | 0.0866 (14) | 0.0533 (13) | 0.0091 (11) | −0.0072 (10) | 0.0044 (12) |
C11 | 0.0574 (11) | 0.0628 (11) | 0.0511 (11) | 0.0143 (9) | 0.0018 (10) | 0.0122 (9) |
C12 | 0.0539 (10) | 0.0610 (11) | 0.0448 (11) | 0.0056 (9) | −0.0074 (9) | −0.0068 (9) |
C13 | 0.0560 (11) | 0.1000 (17) | 0.0554 (13) | 0.0212 (12) | −0.0066 (11) | −0.0157 (13) |
C14 | 0.0453 (11) | 0.131 (2) | 0.0610 (14) | −0.0082 (12) | 0.0035 (11) | −0.0112 (15) |
C15 | 0.0540 (11) | 0.0919 (15) | 0.0615 (13) | −0.0257 (11) | 0.0031 (11) | −0.0036 (13) |
C16 | 0.0545 (10) | 0.0483 (9) | 0.0446 (11) | −0.0065 (8) | −0.0006 (9) | 0.0095 (8) |
C17 | 0.0632 (11) | 0.0407 (8) | 0.0384 (10) | −0.0004 (8) | 0.0064 (10) | 0.0056 (8) |
C18 | 0.0885 (15) | 0.0558 (11) | 0.0404 (11) | −0.0061 (11) | −0.0077 (11) | 0.0014 (9) |
N1—C2 | 1.424 (2) | C14—C15 | 1.369 (3) |
N1—C7 | 1.429 (2) | C16—C17 | 1.454 (3) |
N1—C16 | 1.463 (2) | C17—C18 | 1.178 (3) |
C2—C3 | 1.401 (2) | C4—H4 | 0.9500 |
C2—C12 | 1.386 (2) | C5—H5 | 0.9500 |
C3—C4 | 1.459 (2) | C8—H8 | 0.9500 |
C3—C15 | 1.393 (3) | C9—H9 | 0.9500 |
C4—C5 | 1.319 (3) | C10—H10 | 0.9500 |
C5—C6 | 1.457 (2) | C11—H11 | 0.9500 |
C6—C7 | 1.401 (2) | C12—H12 | 0.9500 |
C6—C11 | 1.389 (3) | C13—H13 | 0.9500 |
C7—C8 | 1.386 (2) | C14—H14 | 0.9500 |
C8—C9 | 1.384 (3) | C15—H15 | 0.9500 |
C9—C10 | 1.373 (3) | C16—H16A | 0.9900 |
C10—C11 | 1.372 (3) | C16—H16B | 0.9900 |
C12—C13 | 1.382 (3) | C18—H18 | 0.9500 |
C13—C14 | 1.374 (4) | ||
C2—N1—C7 | 114.53 (14) | C3—C4—H4 | 117.00 |
C2—N1—C16 | 117.15 (13) | C5—C4—H4 | 117.00 |
C7—N1—C16 | 116.10 (13) | C4—C5—H5 | 117.00 |
N1—C2—C3 | 117.96 (14) | C6—C5—H5 | 116.00 |
N1—C2—C12 | 122.26 (15) | C7—C8—H8 | 120.00 |
C3—C2—C12 | 119.77 (16) | C9—C8—H8 | 120.00 |
C2—C3—C4 | 123.10 (16) | C8—C9—H9 | 120.00 |
C2—C3—C15 | 118.11 (17) | C10—C9—H9 | 120.00 |
C4—C3—C15 | 118.76 (17) | C9—C10—H10 | 120.00 |
C3—C4—C5 | 126.88 (16) | C11—C10—H10 | 120.00 |
C4—C5—C6 | 127.00 (15) | C6—C11—H11 | 119.00 |
C5—C6—C7 | 122.38 (16) | C10—C11—H11 | 119.00 |
C5—C6—C11 | 119.39 (16) | C2—C12—H12 | 120.00 |
C7—C6—C11 | 118.21 (15) | C13—C12—H12 | 120.00 |
N1—C7—C6 | 118.38 (14) | C12—C13—H13 | 120.00 |
N1—C7—C8 | 122.01 (14) | C14—C13—H13 | 120.00 |
C6—C7—C8 | 119.58 (15) | C13—C14—H14 | 120.00 |
C7—C8—C9 | 120.57 (16) | C15—C14—H14 | 120.00 |
C8—C9—C10 | 120.19 (17) | C3—C15—H15 | 119.00 |
C9—C10—C11 | 119.39 (18) | C14—C15—H15 | 119.00 |
C6—C11—C10 | 121.97 (18) | N1—C16—H16A | 109.00 |
C2—C12—C13 | 120.44 (18) | N1—C16—H16B | 109.00 |
C12—C13—C14 | 120.3 (2) | C17—C16—H16A | 109.00 |
C13—C14—C15 | 119.5 (2) | C17—C16—H16B | 109.00 |
C3—C15—C14 | 121.9 (2) | H16A—C16—H16B | 108.00 |
N1—C16—C17 | 110.96 (14) | C17—C18—H18 | 180.00 |
C16—C17—C18 | 179.8 (2) | ||
C7—N1—C2—C3 | 69.0 (2) | C4—C3—C15—C14 | −178.4 (2) |
C7—N1—C2—C12 | −112.4 (2) | C3—C4—C5—C6 | −0.8 (4) |
C16—N1—C2—C3 | −149.95 (18) | C4—C5—C6—C7 | 32.0 (3) |
C16—N1—C2—C12 | 28.6 (3) | C4—C5—C6—C11 | −146.4 (2) |
C2—N1—C7—C6 | −72.36 (18) | C5—C6—C7—N1 | 7.6 (3) |
C2—N1—C7—C8 | 110.12 (17) | C5—C6—C7—C8 | −174.84 (18) |
C16—N1—C7—C6 | 146.21 (16) | C11—C6—C7—N1 | −174.02 (16) |
C16—N1—C7—C8 | −31.3 (2) | C11—C6—C7—C8 | 3.6 (3) |
C2—N1—C16—C17 | 58.9 (2) | C5—C6—C11—C10 | 175.77 (19) |
C7—N1—C16—C17 | −160.75 (14) | C7—C6—C11—C10 | −2.7 (3) |
N1—C2—C3—C4 | −2.9 (3) | N1—C7—C8—C9 | 175.51 (16) |
N1—C2—C3—C15 | 178.7 (2) | C6—C7—C8—C9 | −2.0 (3) |
C12—C2—C3—C4 | 178.5 (2) | C7—C8—C9—C10 | −0.6 (3) |
C12—C2—C3—C15 | 0.1 (3) | C8—C9—C10—C11 | 1.6 (3) |
N1—C2—C12—C13 | −178.59 (19) | C9—C10—C11—C6 | 0.1 (3) |
C3—C2—C12—C13 | 0.0 (3) | C2—C12—C13—C14 | −0.3 (3) |
C2—C3—C4—C5 | −33.6 (4) | C12—C13—C14—C15 | 0.5 (4) |
C15—C3—C4—C5 | 144.8 (2) | C13—C14—C15—C3 | −0.4 (4) |
C2—C3—C15—C14 | 0.1 (4) |
Cg1 and Cg2 are the centroids of the C2/C3/C12–C15 and C6-C11 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10···Cg2i | 0.95 | 2.75 | 3.659 (2) | 160 |
C18—H18···Cg1ii | 0.95 | 2.58 | 3.512 (2) | 167 |
Symmetry codes: (i) −x, y, z−1/2; (ii) x, y, z+1. |
Experimental details
Crystal data | |
Chemical formula | C17H13N |
Mr | 231.28 |
Crystal system, space group | Orthorhombic, Iba2 |
Temperature (K) | 103 |
a, b, c (Å) | 16.2444 (6), 21.1700 (6), 7.2399 (2) |
V (Å3) | 2489.76 (13) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.35 × 0.30 × 0.25 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur Eos |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10081, 1199, 1132 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.026, 0.067, 1.09 |
No. of reflections | 1199 |
No. of parameters | 164 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.08, −0.10 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2006).
Cg1 and Cg2 are the centroids of the C2/C3/C12–C15 and C6-C11 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10···Cg2i | 0.95 | 2.75 | 3.659 (2) | 160 |
C18—H18···Cg1ii | 0.95 | 2.58 | 3.512 (2) | 167 |
Symmetry codes: (i) −x, y, z−1/2; (ii) x, y, z+1. |
Acknowledgements
SMK thanks UGC–BRS and University of Mysore for the award of a fellowship. MPS gratefully acknowledges financial support (grant No. 37–456/2009[SR]) from the University Grants Commission, New Delhi, India.
References
Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453–457. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England. Google Scholar
Sadashiva, M. P., Mallesha, H., KarunakaraMurthy, K. & Rangappa, K. S. (2005). Bioorg. Med. Chem. Lett. 15, 1811–1814. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Yousuf, S., Khan, M., Fazal, S., Butt, M. & Basha, F. Z. (2012). Acta Cryst. E68, o1101. CSD CrossRef IUCr Journals Google Scholar
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As part of our studies of new derivatives useful for tailoring of biologically active 5-membered heterocyclic rings such as 3,5-disubstituted isoxazole (Sadashiva et al., 2005), we now describe the title compound.
In the title molecule, C17 H13 N (Fig. 1.), benzene rings fused to azepine rings are nearly planar and its geometry is similar to 5-(Prop-2-ynyl)-5H-dibenzo[b,f]azepine (Yousuf et al., 2012). The dihedral angle between the benzene rings is 55.99 (10)° which is almost equal and large compared to the two molecules repectively for the first polymorph.
Seven-membered azepine ring adopts a boat conformation as indicated by the puckering parameters Q2 = 0.7126 (18) Å, Q3 = 0.2154 (17) Å, φ2 = 177.93 (15) °, φ3 = 178.1 (5) °, and the total puckering amplitude QT = 0.7444 (17) Å. The title molecule adopts butterfly shape which may be essential for inhibition pocket which is similar to the reported polymorph (Yousuf et al., 2012).
The packing of the title molecules is as shown (Fig. 2.) and features short C—H···π contacts (Table 1).