organic compounds
(2E,2′E)-1,1′-Bis(2,5-dimethyl-3-thienyl)-3,3′-(p-phenylene)diprop-2-en-1-one
aChemistry Department, Faculty of Science, King Abdul Aziz University, Jeddah, Saudi Arabia, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
In the title bis-chalcone, C24H22O2S2, the –C(O)CH=CH–C6H4–CH=CHC(O)– portion is planar (r.m.s. deviation = 0.04 Å); one thienyl ring is aligned at 8.8 (1)° with respect to this fragment, whereas the other is aligned at 21.3 (1)°.
Related literature
et al. (2008); such properties are dramatically enhanced in bis-chalcones. For the crystal structures of some bis-chalcones, see: Harrison et al. (2007a,b,c); Prajapati et al. (2008).
possess anti-bacterial, anti-fungal and anti-inflammatory properties, see: YarishkinExperimental
Crystal data
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Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).
Supporting information
10.1107/S1600536809024581/tk2486sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809024581/tk2486Isup2.hkl
A solution of 3-acetyl-2,5-dimethylthiophene (3.13 ml, 0.0074 mol) and terephthaldehyde (2 g, 0.0074 mol) in ethanolic sodium hydroxide (60%) was stirred for 20 h at room temperature. The solution was poured into ice-cold water and the pH of the mixture was adjusted to 2 by the addition of concentrated hydrochloric acid. The solid that separated was dissolved in dichloromethane and then washed with saturated sodium bicarbonate. The residual obtained upon removal of the solvent was recrystallized from a methanol–chloroform (1/1) mixture in 80% yield; m.p. 467–468 K.
Carbon-bound H-atoms were placed in calculated positions (C—H 0.95–0.98 Å) and were included in the
in the riding model approximation with U(H) fixed at 1.2–1.5Ueq(C).Data collection: APEX2 (Bruker, 2008); cell
SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C24H22O2S2 at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. |
C24H22O2S2 | F(000) = 856 |
Mr = 406.54 | Dx = 1.343 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 765 reflections |
a = 15.6120 (12) Å | θ = 2.8–19.6° |
b = 7.5600 (6) Å | µ = 0.28 mm−1 |
c = 18.2863 (14) Å | T = 140 K |
β = 111.305 (4)° | Plate, yellow |
V = 2010.8 (3) Å3 | 0.40 × 0.10 × 0.01 mm |
Z = 4 |
Bruker SMART APEX diffractometer | 3537 independent reflections |
Radiation source: fine-focus sealed tube | 2102 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.098 |
ω scans | θmax = 25.0°, θmin = 1.4° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −18→18 |
Tmin = 0.896, Tmax = 0.997 | k = −8→8 |
10889 measured reflections | l = −21→21 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.052 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.125 | H-atom parameters constrained |
S = 0.97 | w = 1/[σ2(Fo2) + (0.0496P)2] where P = (Fo2 + 2Fc2)/3 |
3537 reflections | (Δ/σ)max = 0.001 |
257 parameters | Δρmax = 0.27 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C24H22O2S2 | V = 2010.8 (3) Å3 |
Mr = 406.54 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 15.6120 (12) Å | µ = 0.28 mm−1 |
b = 7.5600 (6) Å | T = 140 K |
c = 18.2863 (14) Å | 0.40 × 0.10 × 0.01 mm |
β = 111.305 (4)° |
Bruker SMART APEX diffractometer | 3537 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2102 reflections with I > 2σ(I) |
Tmin = 0.896, Tmax = 0.997 | Rint = 0.098 |
10889 measured reflections |
R[F2 > 2σ(F2)] = 0.052 | 0 restraints |
wR(F2) = 0.125 | H-atom parameters constrained |
S = 0.97 | Δρmax = 0.27 e Å−3 |
3537 reflections | Δρmin = −0.28 e Å−3 |
257 parameters |
x | y | z | Uiso*/Ueq | ||
S1 | 0.05024 (6) | 0.83736 (12) | 0.17666 (5) | 0.0311 (3) | |
S2 | 0.83487 (6) | −0.22707 (12) | 0.99588 (5) | 0.0309 (3) | |
O1 | 0.27593 (18) | 0.9170 (3) | 0.41549 (14) | 0.0387 (7) | |
O2 | 0.64980 (17) | −0.3043 (3) | 0.73797 (14) | 0.0377 (7) | |
C1 | 0.0397 (3) | 0.4820 (5) | 0.1280 (2) | 0.0389 (10) | |
H1A | 0.0806 | 0.3799 | 0.1347 | 0.058* | |
H1B | 0.0250 | 0.5316 | 0.0753 | 0.058* | |
H1C | −0.0171 | 0.4443 | 0.1346 | 0.058* | |
C2 | 0.0865 (2) | 0.6196 (5) | 0.1881 (2) | 0.0284 (9) | |
C3 | 0.1587 (2) | 0.6012 (5) | 0.2562 (2) | 0.0295 (9) | |
H3 | 0.1891 | 0.4915 | 0.2731 | 0.035* | |
C4 | 0.1860 (2) | 0.7622 (5) | 0.3013 (2) | 0.0264 (8) | |
C5 | 0.1326 (2) | 0.9034 (5) | 0.2631 (2) | 0.0272 (9) | |
C6 | 0.1384 (3) | 1.0950 (4) | 0.2861 (2) | 0.0358 (10) | |
H6A | 0.1373 | 1.1054 | 0.3391 | 0.054* | |
H6B | 0.0860 | 1.1591 | 0.2491 | 0.054* | |
H6C | 0.1958 | 1.1455 | 0.2851 | 0.054* | |
C7 | 0.2590 (2) | 0.7752 (5) | 0.3798 (2) | 0.0268 (8) | |
C8 | 0.3077 (2) | 0.6124 (4) | 0.4165 (2) | 0.0262 (9) | |
H8 | 0.3004 | 0.5090 | 0.3853 | 0.031* | |
C9 | 0.3615 (2) | 0.6057 (4) | 0.4917 (2) | 0.0253 (8) | |
H9 | 0.3682 | 0.7128 | 0.5205 | 0.030* | |
C10 | 0.4115 (2) | 0.4536 (4) | 0.53522 (19) | 0.0214 (8) | |
C11 | 0.4739 (2) | 0.4748 (5) | 0.61117 (19) | 0.0249 (8) | |
H11 | 0.4832 | 0.5891 | 0.6344 | 0.030* | |
C12 | 0.5228 (2) | 0.3329 (5) | 0.6538 (2) | 0.0270 (9) | |
H12 | 0.5657 | 0.3513 | 0.7056 | 0.032* | |
C13 | 0.5099 (2) | 0.1626 (4) | 0.6218 (2) | 0.0242 (8) | |
C14 | 0.4463 (2) | 0.1415 (5) | 0.5455 (2) | 0.0253 (8) | |
H14 | 0.4363 | 0.0269 | 0.5227 | 0.030* | |
C15 | 0.3978 (2) | 0.2827 (4) | 0.50260 (19) | 0.0243 (8) | |
H15 | 0.3549 | 0.2645 | 0.4508 | 0.029* | |
C16 | 0.5607 (2) | 0.0092 (5) | 0.66412 (19) | 0.0264 (9) | |
H16 | 0.5522 | −0.0976 | 0.6350 | 0.032* | |
C17 | 0.6172 (2) | 0.0010 (5) | 0.7384 (2) | 0.0272 (9) | |
H17 | 0.6275 | 0.1049 | 0.7696 | 0.033* | |
C18 | 0.6650 (2) | −0.1639 (5) | 0.7744 (2) | 0.0265 (9) | |
C19 | 0.7270 (2) | −0.4819 (4) | 0.8930 (2) | 0.0322 (9) | |
H19A | 0.6629 | −0.4868 | 0.8568 | 0.048* | |
H19B | 0.7321 | −0.5351 | 0.9433 | 0.048* | |
H19C | 0.7658 | −0.5473 | 0.8706 | 0.048* | |
C20 | 0.7578 (2) | −0.2932 (4) | 0.9058 (2) | 0.0256 (8) | |
C21 | 0.7327 (2) | −0.1511 (4) | 0.8555 (2) | 0.0229 (8) | |
C22 | 0.7768 (2) | 0.0090 (5) | 0.8912 (2) | 0.0274 (9) | |
H22 | 0.7658 | 0.1194 | 0.8646 | 0.033* | |
C23 | 0.8357 (2) | −0.0104 (4) | 0.9663 (2) | 0.0276 (9) | |
C24 | 0.8943 (2) | 0.1272 (5) | 1.0203 (2) | 0.0373 (10) | |
H24A | 0.8767 | 0.2445 | 0.9968 | 0.056* | |
H24B | 0.9591 | 0.1050 | 1.0287 | 0.056* | |
H24C | 0.8856 | 0.1224 | 1.0707 | 0.056* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0305 (5) | 0.0267 (5) | 0.0311 (6) | 0.0034 (4) | 0.0052 (4) | 0.0043 (4) |
S2 | 0.0339 (6) | 0.0282 (6) | 0.0260 (5) | 0.0042 (4) | 0.0055 (4) | 0.0039 (4) |
O1 | 0.0514 (17) | 0.0216 (15) | 0.0339 (15) | 0.0018 (13) | 0.0046 (13) | −0.0036 (13) |
O2 | 0.0467 (17) | 0.0211 (15) | 0.0347 (16) | 0.0028 (12) | 0.0020 (13) | −0.0040 (13) |
C1 | 0.040 (2) | 0.034 (2) | 0.035 (2) | 0.002 (2) | 0.0059 (19) | −0.006 (2) |
C2 | 0.033 (2) | 0.024 (2) | 0.027 (2) | 0.0048 (17) | 0.0091 (18) | 0.0001 (17) |
C3 | 0.033 (2) | 0.017 (2) | 0.033 (2) | 0.0030 (17) | 0.0068 (18) | −0.0027 (17) |
C4 | 0.030 (2) | 0.023 (2) | 0.029 (2) | 0.0000 (17) | 0.0133 (17) | 0.0014 (18) |
C5 | 0.028 (2) | 0.023 (2) | 0.031 (2) | −0.0021 (17) | 0.0122 (17) | 0.0001 (18) |
C6 | 0.040 (2) | 0.024 (2) | 0.042 (2) | 0.0027 (19) | 0.012 (2) | 0.0004 (19) |
C7 | 0.032 (2) | 0.022 (2) | 0.027 (2) | −0.0032 (17) | 0.0113 (17) | −0.0004 (18) |
C8 | 0.031 (2) | 0.018 (2) | 0.026 (2) | 0.0015 (16) | 0.0057 (17) | −0.0010 (16) |
C9 | 0.028 (2) | 0.020 (2) | 0.025 (2) | −0.0017 (16) | 0.0062 (17) | −0.0029 (17) |
C10 | 0.0234 (19) | 0.018 (2) | 0.0199 (19) | −0.0017 (15) | 0.0046 (15) | 0.0008 (15) |
C11 | 0.028 (2) | 0.020 (2) | 0.026 (2) | −0.0042 (16) | 0.0091 (16) | −0.0046 (17) |
C12 | 0.027 (2) | 0.029 (2) | 0.0200 (19) | −0.0022 (17) | 0.0021 (16) | 0.0012 (17) |
C13 | 0.0280 (19) | 0.021 (2) | 0.024 (2) | 0.0010 (17) | 0.0091 (16) | 0.0021 (17) |
C14 | 0.029 (2) | 0.021 (2) | 0.025 (2) | −0.0014 (16) | 0.0085 (17) | −0.0040 (17) |
C15 | 0.0236 (19) | 0.024 (2) | 0.0221 (19) | −0.0033 (16) | 0.0041 (16) | −0.0017 (17) |
C16 | 0.0256 (19) | 0.023 (2) | 0.028 (2) | −0.0041 (17) | 0.0065 (17) | −0.0040 (17) |
C17 | 0.032 (2) | 0.020 (2) | 0.028 (2) | 0.0012 (17) | 0.0101 (17) | −0.0016 (17) |
C18 | 0.027 (2) | 0.024 (2) | 0.029 (2) | 0.0014 (17) | 0.0101 (17) | 0.0018 (18) |
C19 | 0.036 (2) | 0.023 (2) | 0.038 (2) | 0.0039 (17) | 0.0137 (18) | 0.0047 (18) |
C20 | 0.0252 (19) | 0.022 (2) | 0.029 (2) | 0.0046 (16) | 0.0082 (16) | 0.0006 (17) |
C21 | 0.0240 (18) | 0.022 (2) | 0.0227 (19) | 0.0032 (16) | 0.0081 (15) | 0.0026 (17) |
C22 | 0.032 (2) | 0.021 (2) | 0.027 (2) | 0.0033 (17) | 0.0079 (17) | 0.0025 (17) |
C23 | 0.028 (2) | 0.024 (2) | 0.030 (2) | 0.0069 (17) | 0.0090 (17) | 0.0010 (18) |
C24 | 0.036 (2) | 0.029 (2) | 0.040 (2) | −0.0009 (18) | 0.0046 (19) | −0.0024 (19) |
S1—C5 | 1.710 (4) | C11—C12 | 1.382 (4) |
S1—C2 | 1.729 (3) | C11—H11 | 0.9500 |
S2—C23 | 1.726 (4) | C12—C13 | 1.398 (5) |
S2—C20 | 1.723 (3) | C12—H12 | 0.9500 |
O1—C7 | 1.233 (4) | C13—C14 | 1.396 (5) |
O2—C18 | 1.230 (4) | C13—C16 | 1.458 (4) |
C1—C2 | 1.497 (5) | C14—C15 | 1.378 (4) |
C1—H1A | 0.9800 | C14—H14 | 0.9500 |
C1—H1B | 0.9800 | C15—H15 | 0.9500 |
C1—H1C | 0.9800 | C16—C17 | 1.325 (4) |
C2—C3 | 1.348 (5) | C16—H16 | 0.9500 |
C3—C4 | 1.445 (5) | C17—C18 | 1.479 (5) |
C3—H3 | 0.9500 | C17—H17 | 0.9500 |
C4—C5 | 1.378 (5) | C18—C21 | 1.479 (5) |
C4—C7 | 1.475 (5) | C19—C20 | 1.497 (4) |
C5—C6 | 1.502 (5) | C19—H19A | 0.9800 |
C6—H6A | 0.9800 | C19—H19B | 0.9800 |
C6—H6B | 0.9800 | C19—H19C | 0.9800 |
C6—H6C | 0.9800 | C20—C21 | 1.375 (4) |
C7—C8 | 1.474 (5) | C21—C22 | 1.428 (5) |
C8—C9 | 1.327 (5) | C22—C23 | 1.355 (5) |
C8—H8 | 0.9500 | C22—H22 | 0.9500 |
C9—C10 | 1.453 (4) | C23—C24 | 1.496 (5) |
C9—H9 | 0.9500 | C24—H24A | 0.9800 |
C10—C11 | 1.386 (4) | C24—H24B | 0.9800 |
C10—C15 | 1.407 (4) | C24—H24C | 0.9800 |
C5—S1—C2 | 93.59 (17) | C13—C12—H12 | 119.6 |
C23—S2—C20 | 93.32 (16) | C14—C13—C12 | 117.7 (3) |
C2—C1—H1A | 109.5 | C14—C13—C16 | 119.4 (3) |
C2—C1—H1B | 109.5 | C12—C13—C16 | 122.8 (3) |
H1A—C1—H1B | 109.5 | C15—C14—C13 | 121.7 (3) |
C2—C1—H1C | 109.5 | C15—C14—H14 | 119.2 |
H1A—C1—H1C | 109.5 | C13—C14—H14 | 119.2 |
H1B—C1—H1C | 109.5 | C14—C15—C10 | 120.2 (3) |
C3—C2—C1 | 128.9 (3) | C14—C15—H15 | 119.9 |
C3—C2—S1 | 109.7 (3) | C10—C15—H15 | 119.9 |
C1—C2—S1 | 121.4 (3) | C17—C16—C13 | 127.7 (3) |
C2—C3—C4 | 114.5 (3) | C17—C16—H16 | 116.1 |
C2—C3—H3 | 122.7 | C13—C16—H16 | 116.1 |
C4—C3—H3 | 122.7 | C16—C17—C18 | 122.5 (3) |
C5—C4—C3 | 111.3 (3) | C16—C17—H17 | 118.8 |
C5—C4—C7 | 123.6 (3) | C18—C17—H17 | 118.8 |
C3—C4—C7 | 125.0 (3) | O2—C18—C17 | 121.2 (3) |
C4—C5—C6 | 129.9 (3) | O2—C18—C21 | 121.8 (3) |
C4—C5—S1 | 110.9 (3) | C17—C18—C21 | 116.9 (3) |
C6—C5—S1 | 119.3 (3) | C20—C19—H19A | 109.5 |
C5—C6—H6A | 109.5 | C20—C19—H19B | 109.5 |
C5—C6—H6B | 109.5 | H19A—C19—H19B | 109.5 |
H6A—C6—H6B | 109.5 | C20—C19—H19C | 109.5 |
C5—C6—H6C | 109.5 | H19A—C19—H19C | 109.5 |
H6A—C6—H6C | 109.5 | H19B—C19—H19C | 109.5 |
H6B—C6—H6C | 109.5 | C21—C20—C19 | 130.0 (3) |
O1—C7—C8 | 120.6 (3) | C21—C20—S2 | 110.1 (3) |
O1—C7—C4 | 120.9 (3) | C19—C20—S2 | 119.9 (3) |
C8—C7—C4 | 118.4 (3) | C20—C21—C22 | 112.6 (3) |
C9—C8—C7 | 122.1 (3) | C20—C21—C18 | 123.1 (3) |
C9—C8—H8 | 118.9 | C22—C21—C18 | 124.3 (3) |
C7—C8—H8 | 118.9 | C23—C22—C21 | 114.1 (3) |
C8—C9—C10 | 127.5 (3) | C23—C22—H22 | 123.0 |
C8—C9—H9 | 116.2 | C21—C22—H22 | 123.0 |
C10—C9—H9 | 116.2 | C22—C23—C24 | 128.3 (3) |
C11—C10—C15 | 118.3 (3) | C22—C23—S2 | 109.9 (3) |
C11—C10—C9 | 120.0 (3) | C24—C23—S2 | 121.7 (3) |
C15—C10—C9 | 121.7 (3) | C23—C24—H24A | 109.5 |
C12—C11—C10 | 121.3 (3) | C23—C24—H24B | 109.5 |
C12—C11—H11 | 119.4 | H24A—C24—H24B | 109.5 |
C10—C11—H11 | 119.4 | C23—C24—H24C | 109.5 |
C11—C12—C13 | 120.8 (3) | H24A—C24—H24C | 109.5 |
C11—C12—H12 | 119.6 | H24B—C24—H24C | 109.5 |
C5—S1—C2—C3 | 0.4 (3) | C12—C13—C14—C15 | 0.2 (5) |
C5—S1—C2—C1 | −179.9 (3) | C16—C13—C14—C15 | −178.9 (3) |
C1—C2—C3—C4 | −179.1 (3) | C13—C14—C15—C10 | 0.0 (5) |
S1—C2—C3—C4 | 0.6 (4) | C11—C10—C15—C14 | −0.6 (5) |
C2—C3—C4—C5 | −1.6 (5) | C9—C10—C15—C14 | 180.0 (3) |
C2—C3—C4—C7 | 176.2 (3) | C14—C13—C16—C17 | −173.7 (3) |
C3—C4—C5—C6 | −177.4 (4) | C12—C13—C16—C17 | 7.2 (6) |
C7—C4—C5—C6 | 4.8 (6) | C13—C16—C17—C18 | −179.8 (3) |
C3—C4—C5—S1 | 1.8 (4) | C16—C17—C18—O2 | −4.4 (5) |
C7—C4—C5—S1 | −176.0 (3) | C16—C17—C18—C21 | 174.5 (3) |
C2—S1—C5—C4 | −1.3 (3) | C23—S2—C20—C21 | −1.1 (3) |
C2—S1—C5—C6 | 178.0 (3) | C23—S2—C20—C19 | −179.8 (3) |
C5—C4—C7—O1 | 0.0 (5) | C19—C20—C21—C22 | 178.7 (3) |
C3—C4—C7—O1 | −177.6 (3) | S2—C20—C21—C22 | 0.1 (4) |
C5—C4—C7—C8 | 176.5 (3) | C19—C20—C21—C18 | 0.6 (6) |
C3—C4—C7—C8 | −1.0 (5) | S2—C20—C21—C18 | −178.0 (3) |
O1—C7—C8—C9 | 9.4 (5) | O2—C18—C21—C20 | −24.7 (5) |
C4—C7—C8—C9 | −167.2 (3) | C17—C18—C21—C20 | 156.4 (3) |
C7—C8—C9—C10 | 178.5 (3) | O2—C18—C21—C22 | 157.4 (3) |
C8—C9—C10—C11 | 171.8 (3) | C17—C18—C21—C22 | −21.5 (5) |
C8—C9—C10—C15 | −8.8 (6) | C20—C21—C22—C23 | 1.3 (4) |
C15—C10—C11—C12 | 1.0 (5) | C18—C21—C22—C23 | 179.3 (3) |
C9—C10—C11—C12 | −179.6 (3) | C21—C22—C23—C24 | 178.6 (3) |
C10—C11—C12—C13 | −0.8 (5) | C21—C22—C23—S2 | −2.0 (4) |
C11—C12—C13—C14 | 0.2 (5) | C20—S2—C23—C22 | 1.8 (3) |
C11—C12—C13—C16 | 179.2 (3) | C20—S2—C23—C24 | −178.8 (3) |
Experimental details
Crystal data | |
Chemical formula | C24H22O2S2 |
Mr | 406.54 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 140 |
a, b, c (Å) | 15.6120 (12), 7.5600 (6), 18.2863 (14) |
β (°) | 111.305 (4) |
V (Å3) | 2010.8 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.28 |
Crystal size (mm) | 0.40 × 0.10 × 0.01 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.896, 0.997 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10889, 3537, 2102 |
Rint | 0.098 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.052, 0.125, 0.97 |
No. of reflections | 3537 |
No. of parameters | 257 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.27, −0.28 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).
Acknowledgements
We thank King Abdul Aziz University and the University of Malaya for supporting this study.
References
Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Harrison, W. T. A., Ravindra, H. J., Suresh Kumar, M. R. & Dharmaprakash, S. M. (2007a). Acta Cryst. E63, o3068. Web of Science CSD CrossRef IUCr Journals Google Scholar
Harrison, W. T. A., Ravindra, H. J., Kumar, M. R. S. & Dharmaprakash, S. M. (2007b). Acta Cryst. E63, o3702. Web of Science CSD CrossRef IUCr Journals Google Scholar
Harrison, W. T. A., Ravindra, H. J., Kumar, M. R. S. & Dharmaprakash, S. M. (2007c). Acta Cryst. E63, o3706. Google Scholar
Prajapati, R., Mishra, L., Grabowski, S. J., Govil, C. & Dubey, S. K. (2008). J. Mol. Struct. 879, 1–6. Web of Science CSD CrossRef CAS Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2009). publCIF. In preparation. Google Scholar
Yarishkin, O. V., Ryu, H. W., Park, J.-Y., Yang, M. S., Hong, S.-G. & Park, K.-H. (2008). Bioorg. Med. Chem. Lett. 18, 137–140. Web of Science CrossRef PubMed CAS Google Scholar
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