organic compounds
1-[(2E)-3-Phenylprop-2-en-1-yl]-1H-indole-2,3-dione
aLaboratoire de Chimie Organique Appliquée-Chimie Appliquée, Faculté des Sciences et Techniques, Université Sidi Mohamed Ben Abdallah, Fès, Morocco, bLaboratoire de Chimie Organique Hétérocyclique, Pôle de Compétences Pharmacochimie, Mohammed V University in Rabat, BP 1014, Avenue Ibn Batouta, Rabat, Morocco, cUnité de Catalyse et de Chimie du Solide (UCCS), UMR 8181., Ecole Nationale Supérieure de Chimie de Lille, France, and dLaboratoire d'Ingénierie des Matériaux et d'Environnement: Modélisation et Application (LIMEMA), Ibn Tofail University, Kénitra, Morocco
*Correspondence e-mail: hafid.zouihri@gmail.com
In the title compound, C17H13NO2, the indole ring is essentially planar (r.m.s. deviation = 0.027 Å) and is oriented at an angle of 69.33 (7)° with respect to the phenyl ring. In the crystal, C—H⋯O hydrogen bonds link the molecules, forming zigzag chains propagating along the a-axis direction. Within the chains there are π–π stacking interactions [centroid–centroid distances = 3.7163 (8) and 3.7162 (8) Å] involving isatin groups of neighbouring molecules.
Keywords: crystal structure; indoline; hydrogen bonding; π–π stacking.
CCDC reference: 1474205
Structure description
The importance of the indole derivatives in different fields and, in particular, chemistry, biology and pharmacology, has prompted researchers to develop many synthetic methods for their preparation and to find new applications. Isatin (indoline-2,3-dione) has provoked tremendous interest due to its numerous biological and pharmacological activities. The growing importance of substituted isatins in the field of medicinal chemistry as potential chemotherapeutic agents and their implications for prodrug design have been reported (Matesic et al., 2008; Wang et al., 2008; Lane et al., 2001; Patyna et al., 2006). As a continuation of our research devoted to the development of isatin derivatives (Qachchachi et al., 2014a,b), we report herein on the synthesis and of a new indoline-2,3-dione derivative.
In the title compound, Fig. 1, the indole ring system is essentially planar, with an r.m.s. deviation of 0.027 Å, and is oriented at an angle of 69.33 (7) ° with respect to the phenyl ring.
In the crystal, C—H⋯O hydrogen bonds link the molecules, and lead to the formation of zigzag chains parallel to the a axis (Table 1 and Fig. 2). There are weak π–π stacking [centroid–centroid separations = 3.7163 (8) and 3.7162 (8) Å] interactions present involving the six-membered rings (C1–C6) of the isatin groups of neighbouring molecules in the chain.
Synthesis and crystallization
To a solution of isatin (0.2 g, 1.4 mmol) dissolved in DMF(10 ml) was added potassium carbonate (0.33 g, 2.38 mmol), a catalytic quantity of tetra-n-butylammonium bromide (0.04 g, 0.11 mmol) and 3-bromo-1-phenyl-1-propene (0.3 g, 1.5 mmol). The mixture was stirred for 48 h; the reaction was monitored by thin layer On completion of the reaction, the mixture was filtered and the solvent removed under vacuum. The solid obtained was recrystallized from ethanol to afford the title compound as orange crystals (yield 86%; m.p. = 413 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1474205
10.1107/S2414314616006337/su4035sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2414314616006337/su4035Isup2.hkl
Supporting information file. DOI: 10.1107/S2414314616006337/su4035Isup3.cml
To a solution of isatin (0.2 g, 1.4 mmol) dissolved in DMF(10 ml) was added potassium carbonate (0.33 g, 2.38 mmol), a catalytic quantity of tetra-n-butylammonium bromide (0.04 g, 0.11 mmol) and 3-bromo-1-phenyl-1-propene (0.3 g, 1.5 mmol). The mixture was stirred for 48 h; the reaction was monitored by thin layer
On completion of the reaction, the mixture was filtered and the solvent removed under vacuum. The solid obtained was recrystallized from ethanol to afford the title compound as orange crystals (yield 86%; m.p .= 413 K).The importance of the indole derivatives in different fields and, in particular, chemistry, biology and pharmacology, has prompted researchers to develop many synthetic methods for their preparation and to find new applications. Isatin (indoline-2,3-dione) has provoked tremendous interest due to its numerous biological and pharmacological activities. The growing importance of substituted isatins in the field of medicinal chemistry as potential chemotherapeutic agents and their implications for prodrug design have been reported (Matesic et al., 2008; Wang et al., 2008; Lane et al., 2001; Patyna et al., 2006). As a continuation of our research devoted to the development of isatin derivatives (Qachchachi et al., 2014a,b), we report herein on the synthesis and
of a new indoline-2,3-dione derivative.In the title compound, Fig. 1, the indole ring system is essentially planar, with an r.m.s. deviation of 0.027 Å, and is oriented at an angle of 69.33 (7) ° with respect to the phenyl ring.
In the crystal, C—H···O hydrogen bonds link the molecules, and lead to the formation of zigzag chains parallel to the a axis (Table 1 and Fig. 2). There are weak π–π stacking [centroid–centroid separations = 3.7163 (8) and 3.7162 (8) Å] interactions present involving the six-membered rings (C1–C6) of the isatin groups of neighbouring molecules in the chain.
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).Fig. 1. View of the molecular structure of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. | |
Fig. 2. View along the b axis of the crystal packing of the title compound. Dashed lines indicate hydrogen bonds (see Table 1). |
C17H13NO2 | Dx = 1.310 Mg m−3 |
Mr = 263.28 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pbca | Cell parameters from 5160 reflections |
a = 8.2585 (2) Å | θ = 2.6–26.3° |
b = 7.2677 (1) Å | µ = 0.09 mm−1 |
c = 44.4667 (8) Å | T = 296 K |
V = 2668.90 (9) Å3 | Prism, orange |
Z = 8 | 0.60 × 0.25 × 0.10 mm |
F(000) = 1104 |
Bruker APEXII CCD diffractometer | 2571 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.041 |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | θmax = 30.5°, θmin = 3.1° |
Tmin = 0.689, Tmax = 0.746 | h = −11→11 |
23607 measured reflections | k = −9→10 |
4060 independent reflections | l = −62→62 |
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)] = 0.047 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.127 | All H-atom parameters refined |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0519P)2 + 0.4017P] where P = (Fo2 + 2Fc2)/3 |
4060 reflections | (Δ/σ)max = 0.001 |
233 parameters | Δρmax = 0.19 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C17H13NO2 | V = 2668.90 (9) Å3 |
Mr = 263.28 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 8.2585 (2) Å | µ = 0.09 mm−1 |
b = 7.2677 (1) Å | T = 296 K |
c = 44.4667 (8) Å | 0.60 × 0.25 × 0.10 mm |
Bruker APEXII CCD diffractometer | 4060 independent reflections |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | 2571 reflections with I > 2σ(I) |
Tmin = 0.689, Tmax = 0.746 | Rint = 0.041 |
23607 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.127 | All H-atom parameters refined |
S = 1.04 | Δρmax = 0.19 e Å−3 |
4060 reflections | Δρmin = −0.17 e Å−3 |
233 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.60603 (15) | 0.50695 (16) | 0.42372 (3) | 0.0383 (3) | |
C2 | 0.77082 (17) | 0.51765 (19) | 0.42004 (4) | 0.0477 (3) | |
C3 | 0.86641 (17) | 0.4597 (2) | 0.44390 (4) | 0.0552 (4) | |
C4 | 0.80102 (18) | 0.3924 (2) | 0.47026 (4) | 0.0530 (4) | |
C5 | 0.63530 (17) | 0.37805 (19) | 0.47351 (3) | 0.0449 (3) | |
C6 | 0.53775 (14) | 0.43512 (17) | 0.44995 (3) | 0.0370 (3) | |
C7 | 0.36259 (15) | 0.43553 (19) | 0.44613 (3) | 0.0429 (3) | |
C8 | 0.33388 (16) | 0.5264 (2) | 0.41483 (3) | 0.0468 (3) | |
C9 | 0.5122 (2) | 0.6473 (2) | 0.37450 (3) | 0.0544 (4) | |
C10 | 0.53530 (19) | 0.5127 (2) | 0.34949 (3) | 0.0519 (4) | |
C11 | 0.49844 (17) | 0.3365 (2) | 0.35012 (3) | 0.0485 (3) | |
C12 | 0.51148 (17) | 0.2088 (2) | 0.32464 (3) | 0.0478 (3) | |
C13 | 0.4109 (2) | 0.0559 (2) | 0.32305 (4) | 0.0661 (4) | |
C14 | 0.4145 (3) | −0.0586 (3) | 0.29827 (5) | 0.0850 (6) | |
C15 | 0.5194 (3) | −0.0252 (3) | 0.27504 (5) | 0.0813 (6) | |
C16 | 0.6240 (3) | 0.1213 (3) | 0.27678 (4) | 0.0736 (5) | |
C17 | 0.6202 (2) | 0.2371 (2) | 0.30122 (3) | 0.0593 (4) | |
H2 | 0.816 (2) | 0.566 (2) | 0.4016 (4) | 0.063 (5)* | |
H3 | 0.980 (2) | 0.473 (2) | 0.4419 (4) | 0.067 (5)* | |
H4 | 0.873 (2) | 0.355 (2) | 0.4865 (4) | 0.070 (5)* | |
H5 | 0.5861 (17) | 0.328 (2) | 0.4922 (3) | 0.051 (4)* | |
H10 | 0.5754 (18) | 0.565 (2) | 0.3313 (4) | 0.061 (4)* | |
H11 | 0.4492 (19) | 0.285 (2) | 0.3686 (4) | 0.067 (4)* | |
H13 | 0.336 (2) | 0.031 (3) | 0.3395 (4) | 0.089 (6)* | |
H14 | 0.342 (3) | −0.158 (3) | 0.2971 (5) | 0.102 (7)* | |
H15 | 0.526 (3) | −0.104 (3) | 0.2577 (5) | 0.109 (7)* | |
H16 | 0.703 (2) | 0.141 (3) | 0.2607 (4) | 0.087 (6)* | |
H17 | 0.695 (2) | 0.338 (3) | 0.3020 (4) | 0.074 (5)* | |
H9A | 0.6096 (18) | 0.722 (2) | 0.3761 (3) | 0.051 (4)* | |
H9B | 0.417 (2) | 0.725 (2) | 0.3698 (4) | 0.072 (5)* | |
N1 | 0.48280 (13) | 0.56265 (16) | 0.40353 (2) | 0.0449 (3) | |
O1 | 0.25550 (12) | 0.37772 (17) | 0.46186 (2) | 0.0631 (3) | |
O2 | 0.20406 (12) | 0.55750 (18) | 0.40305 (2) | 0.0681 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0342 (6) | 0.0341 (6) | 0.0464 (6) | 0.0005 (5) | 0.0018 (5) | −0.0056 (5) |
C2 | 0.0378 (7) | 0.0413 (7) | 0.0640 (8) | −0.0042 (6) | 0.0111 (6) | −0.0084 (6) |
C3 | 0.0284 (7) | 0.0471 (8) | 0.0902 (11) | 0.0016 (6) | −0.0010 (7) | −0.0154 (7) |
C4 | 0.0394 (7) | 0.0489 (8) | 0.0707 (9) | 0.0074 (6) | −0.0167 (7) | −0.0063 (7) |
C5 | 0.0425 (7) | 0.0428 (7) | 0.0495 (7) | 0.0021 (6) | −0.0061 (6) | −0.0019 (6) |
C6 | 0.0296 (6) | 0.0378 (6) | 0.0436 (6) | 0.0017 (5) | 0.0001 (5) | −0.0026 (5) |
C7 | 0.0329 (6) | 0.0530 (8) | 0.0428 (6) | 0.0010 (6) | 0.0017 (5) | −0.0018 (6) |
C8 | 0.0369 (7) | 0.0580 (8) | 0.0456 (7) | 0.0039 (6) | −0.0028 (5) | −0.0008 (6) |
C9 | 0.0663 (10) | 0.0498 (8) | 0.0472 (8) | −0.0036 (8) | 0.0045 (7) | 0.0080 (6) |
C10 | 0.0582 (9) | 0.0546 (9) | 0.0429 (7) | −0.0022 (7) | 0.0059 (6) | 0.0099 (6) |
C11 | 0.0465 (8) | 0.0546 (8) | 0.0443 (7) | −0.0021 (6) | 0.0055 (6) | 0.0087 (6) |
C12 | 0.0474 (8) | 0.0493 (7) | 0.0467 (7) | 0.0030 (6) | −0.0022 (6) | 0.0079 (6) |
C13 | 0.0619 (10) | 0.0590 (10) | 0.0775 (11) | −0.0042 (8) | 0.0033 (9) | 0.0013 (8) |
C14 | 0.0801 (14) | 0.0678 (12) | 0.1070 (16) | −0.0065 (11) | −0.0166 (13) | −0.0168 (11) |
C15 | 0.1023 (16) | 0.0746 (13) | 0.0671 (11) | 0.0209 (12) | −0.0208 (11) | −0.0169 (10) |
C16 | 0.0950 (14) | 0.0745 (12) | 0.0512 (9) | 0.0218 (11) | 0.0070 (9) | 0.0037 (8) |
C17 | 0.0674 (10) | 0.0591 (10) | 0.0512 (8) | 0.0032 (8) | 0.0089 (7) | 0.0060 (7) |
N1 | 0.0429 (6) | 0.0507 (6) | 0.0410 (5) | 0.0005 (5) | 0.0012 (4) | 0.0036 (5) |
O1 | 0.0364 (5) | 0.0969 (9) | 0.0560 (6) | −0.0069 (5) | 0.0069 (5) | 0.0103 (6) |
O2 | 0.0440 (6) | 0.0988 (9) | 0.0614 (6) | 0.0094 (6) | −0.0131 (5) | 0.0108 (6) |
C1—C2 | 1.3730 (19) | C9—H9A | 0.972 (15) |
C1—C6 | 1.3968 (17) | C9—H9B | 0.987 (18) |
C1—N1 | 1.4162 (16) | C10—C11 | 1.316 (2) |
C2—C3 | 1.388 (2) | C10—H10 | 0.952 (16) |
C2—H2 | 0.967 (17) | C11—C12 | 1.469 (2) |
C3—C4 | 1.380 (2) | C11—H11 | 0.990 (16) |
C3—H3 | 0.950 (18) | C12—C13 | 1.389 (2) |
C4—C5 | 1.380 (2) | C12—C17 | 1.390 (2) |
C4—H4 | 0.976 (18) | C13—C14 | 1.381 (3) |
C5—C6 | 1.3850 (18) | C13—H13 | 0.98 (2) |
C5—H5 | 0.994 (14) | C14—C15 | 1.370 (3) |
C6—C7 | 1.4565 (17) | C14—H14 | 0.94 (2) |
C7—O1 | 1.2033 (15) | C15—C16 | 1.374 (3) |
C7—C8 | 1.5583 (19) | C15—H15 | 0.96 (2) |
C8—O2 | 1.2146 (16) | C16—C17 | 1.375 (2) |
C8—N1 | 1.3545 (17) | C16—H16 | 0.98 (2) |
C9—N1 | 1.4504 (18) | C17—H17 | 0.959 (19) |
C9—C10 | 1.494 (2) | ||
C2—C1—C6 | 121.40 (12) | H9A—C9—H9B | 110.9 (13) |
C2—C1—N1 | 128.35 (12) | C11—C10—C9 | 126.28 (13) |
C6—C1—N1 | 110.25 (11) | C11—C10—H10 | 119.1 (10) |
C1—C2—C3 | 117.09 (14) | C9—C10—H10 | 114.5 (10) |
C1—C2—H2 | 120.5 (10) | C10—C11—C12 | 125.53 (13) |
C3—C2—H2 | 122.4 (10) | C10—C11—H11 | 118.5 (10) |
C4—C3—C2 | 122.29 (13) | C12—C11—H11 | 115.7 (10) |
C4—C3—H3 | 120.1 (10) | C13—C12—C17 | 117.78 (15) |
C2—C3—H3 | 117.5 (10) | C13—C12—C11 | 120.06 (13) |
C3—C4—C5 | 120.26 (14) | C17—C12—C11 | 122.14 (14) |
C3—C4—H4 | 119.2 (10) | C14—C13—C12 | 120.66 (18) |
C5—C4—H4 | 120.5 (10) | C14—C13—H13 | 120.0 (12) |
C4—C5—C6 | 118.35 (14) | C12—C13—H13 | 119.3 (12) |
C4—C5—H5 | 121.4 (8) | C15—C14—C13 | 120.5 (2) |
C6—C5—H5 | 120.3 (8) | C15—C14—H14 | 119.7 (14) |
C5—C6—C1 | 120.58 (12) | C13—C14—H14 | 119.7 (14) |
C5—C6—C7 | 131.81 (12) | C14—C15—C16 | 119.52 (19) |
C1—C6—C7 | 107.61 (11) | C14—C15—H15 | 122.3 (14) |
O1—C7—C6 | 131.40 (12) | C16—C15—H15 | 118.1 (14) |
O1—C7—C8 | 123.73 (12) | C15—C16—C17 | 120.31 (19) |
C6—C7—C8 | 104.85 (10) | C15—C16—H16 | 119.7 (12) |
O2—C8—N1 | 127.24 (13) | C17—C16—H16 | 120.0 (12) |
O2—C8—C7 | 126.76 (13) | C16—C17—C12 | 121.11 (18) |
N1—C8—C7 | 106.00 (10) | C16—C17—H17 | 118.9 (11) |
N1—C9—C10 | 113.96 (13) | C12—C17—H17 | 119.9 (11) |
N1—C9—H9A | 107.9 (8) | C8—N1—C1 | 111.20 (10) |
C10—C9—H9A | 108.3 (8) | C8—N1—C9 | 124.38 (12) |
N1—C9—H9B | 107.2 (9) | C1—N1—C9 | 124.42 (12) |
C10—C9—H9B | 108.5 (10) | ||
C6—C1—C2—C3 | −2.10 (19) | C10—C11—C12—C13 | −152.41 (16) |
N1—C1—C2—C3 | 177.52 (12) | C10—C11—C12—C17 | 26.2 (2) |
C1—C2—C3—C4 | 0.6 (2) | C17—C12—C13—C14 | −3.0 (2) |
C2—C3—C4—C5 | 1.0 (2) | C11—C12—C13—C14 | 175.72 (16) |
C3—C4—C5—C6 | −0.9 (2) | C12—C13—C14—C15 | 1.2 (3) |
C4—C5—C6—C1 | −0.60 (19) | C13—C14—C15—C16 | 1.4 (3) |
C4—C5—C6—C7 | 178.91 (13) | C14—C15—C16—C17 | −2.0 (3) |
C2—C1—C6—C5 | 2.17 (19) | C15—C16—C17—C12 | 0.2 (3) |
N1—C1—C6—C5 | −177.51 (11) | C13—C12—C17—C16 | 2.3 (2) |
C2—C1—C6—C7 | −177.44 (12) | C11—C12—C17—C16 | −176.36 (15) |
N1—C1—C6—C7 | 2.88 (14) | O2—C8—N1—C1 | −179.96 (15) |
C5—C6—C7—O1 | −4.3 (3) | C7—C8—N1—C1 | −0.20 (15) |
C1—C6—C7—O1 | 175.27 (15) | O2—C8—N1—C9 | 0.0 (2) |
C5—C6—C7—C8 | 177.60 (13) | C7—C8—N1—C9 | 179.73 (12) |
C1—C6—C7—C8 | −2.84 (14) | C2—C1—N1—C8 | 178.67 (13) |
O1—C7—C8—O2 | 3.3 (2) | C6—C1—N1—C8 | −1.67 (15) |
C6—C7—C8—O2 | −178.36 (14) | C2—C1—N1—C9 | −1.3 (2) |
O1—C7—C8—N1 | −176.42 (13) | C6—C1—N1—C9 | 178.39 (12) |
C6—C7—C8—N1 | 1.88 (14) | C10—C9—N1—C8 | −92.71 (18) |
N1—C9—C10—C11 | 15.3 (2) | C10—C9—N1—C1 | 87.21 (18) |
C9—C10—C11—C12 | 175.49 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···O1i | 0.947 (17) | 2.539 (17) | 3.3642 (17) | 145.8 (13) |
C11—H11···O2ii | 0.990 (17) | 2.585 (16) | 3.5281 (18) | 159.2 (13) |
Symmetry codes: (i) x+1, y, z; (ii) −x+1/2, y−1/2, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···O1i | 0.947 (17) | 2.539 (17) | 3.3642 (17) | 145.8 (13) |
C11—H11···O2ii | 0.990 (17) | 2.585 (16) | 3.5281 (18) | 159.2 (13) |
Symmetry codes: (i) x+1, y, z; (ii) −x+1/2, y−1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C17H13NO2 |
Mr | 263.28 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 296 |
a, b, c (Å) | 8.2585 (2), 7.2677 (1), 44.4667 (8) |
V (Å3) | 2668.90 (9) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.60 × 0.25 × 0.10 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Krause et al., 2015) |
Tmin, Tmax | 0.689, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 23607, 4060, 2571 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.714 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.127, 1.04 |
No. of reflections | 4060 |
No. of parameters | 233 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.19, −0.17 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXT (Sheldrick, 2015a), SHELXL2014 (Sheldrick, 2015b), PLATON (Spek, 2009), publCIF (Westrip, 2010).
References
Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3–10. Web of Science CrossRef CAS IUCr Journals Google Scholar
Lane, M. E., Yu, B., Rice, A., Lipson, K. E., Liang, C., Sun, L., Tang, C., McMahon, G., Pestell, R. G. & Wadler, S. (2001). Cancer Res. 61, 6170–6177. PubMed CAS Google Scholar
Matesic, L., Locke, J. M., Bremner, J. B., Pyne, S. G., Skropeta, D., Ranson, M. & Vine, K. L. (2008). Bioorg. Med. Chem. 16, 3118–3124. Web of Science CrossRef PubMed CAS Google Scholar
Patyna, S., Laird, A. D., Mendel, D. B., O'Farrell, A. M., Liang, C., Guan, H., Vojkovsky, T., Vasile, S., Wang, X., Chen, J., Grazzini, M., Yang, C. Y., Haznedar, J. Ö., Sukbuntherng, J., Zhong, W.-Z., Cherrington, J. M. & Hu-Lowe, D. (2006). Mol. Cancer Therapeut. 5, 1774–1782. CrossRef CAS Google Scholar
Qachchachi, F.-Z., Kandri Rodi, Y., Essassi, E. M., Bodensteiner, M. & El Ammari, L. (2014a). Acta Cryst. E70, o361–o362. CSD CrossRef IUCr Journals Google Scholar
Qachchachi, F.-Z., Kandri Rodi, Y., Essassi, E. M., Bodensteiner, M. & El Ammari, L. (2014b). Acta Cryst. E70, o588. CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015a). Acta Cryst. A71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2015b). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, F., Fang, Y., Zhu, T., Zhang, M., Lin, A., Gu, Q. & Zhu, W. (2008). Tetrahedron, 64, 7986–7991. CrossRef CAS Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
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