The –COOH group of the title compound adopts a syn conformation (O= C—O—H = 0°) unlike the anti conformation observed in related maleamic acids. This is correlated with the formation of carboxylic acid inversion dimers linked by pairwise O—H⋯O hydrogen bonds in the crystal of the title compound rather than an intramolecular O—H⋯O hydrogen bond.
Keywords: crystal structure, hydrogen bonds, maleamic acids, Hirshfeld surface
Abstract
The title molecule, C11H8F3NO3, adopts a cis configuration across the –C=C– double bond in the side chain and the dihedral angle between the phenyl ring and side chain is 47.35 (1)°. The –COOH group adopts a syn conformation (O=C—O—H = 0°), unlike the anti conformation observed in related maleamic acids. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds are connected via N—H⋯O hydrogen bonds and C—H⋯O interactions into (100) sheets, which are cross-linked by another C—H⋯O interaction to result in a three-dimensional network. The Hirshfeld surface fingerprint plots show that the highest contribution to surface contacts arises from O⋯H/H⋯O contacts (26.5%) followed by H⋯F/F⋯H (23.4%) and H⋯H (17.3%).
Chemical context
The development of pH-induced charge-conversion drug-delivery systems can help to overcome the intrinsic pH difference between tumor tissues (pH 6.5–6.8) and normal tissues or the blood stream (pH 7.2–7.4) (Ge et al., 2013 ▸). Reactions of 2,3-dimethylmaleic anhydride (DMMA) and amino groups on the particle surface have been used to shield the positive charge of nanoparticles (Du et al., 2010 ▸). The generated amide bond is cleavable under mildly acidic conditions but is stable at neutral or basic pH, whereas the DMMA-decorated nanoparticles are inert under physiological conditions. After accumulating into the acidic tumor tissue through the enhanced permeation and retention (EPR) effect, the amide bond slowly cleaves and thus exposes the positive charge, which eventually promotes cell internalization. Therefore, maleamic acids and their derivatives, by virtue of their unique weak acid sensitivity and charge conversion have been widely used as smart carriers to deliver nucleic acids (Meyer et al., 2009 ▸), proteins (Zhang et al., 2015 ▸; Lee et al., 2007 ▸) and drugs (Du et al., 2011 ▸; Chen et al., 2015 ▸; Han et al., 2015 ▸). Simple methods to control the ratio of two positional isomers of mono-substituted maleamic acids and a highly efficient way to synthesize di-substituted maleamic acids have been reported (Su et al., 2017 ▸). The hydrolysis profiles of mono- or di-substituted maleamic acids were studied by the same authors to elucidate their hydrolysis selectivity towards various physiologically available pH values (Su et al., 2017 ▸). As part our studies in this area, the synthesis and crystal structure of N-[2-(trifluoromethyl)phenyl]maleamic acid, (I), is described and is further analysed using Hirshfeld surfaces and fingerprint plots and compared to related structures.
Structural commentary
The molecule of (I) adopts a cis configuration across the –C=C– double bond in the side chain (Fig. 1 ▸), similar to that observed in N-(phenyl)maleamic acid (Lo et al., 2009 ▸) and other related o-substituted maleamic acids, viz. N-(2-methylphenyl)maleamic acid (Gowda et al., 2010 ▸) and N-(2-aminophenyl)maleamic acid (Santos-Sánchez et al., 2007 ▸). In (I), the dihedral angle between the planes of the phenyl ring C1–C6 and the side chain C1—N1(O1)—C7—C8—C9 is 47.35 (1)° compared to the reported values of 12.7 (1)° in N-(2-methylphenyl)maleamic acid (Gowda et al., 2010 ▸) and 43.08 (10)° in N-(2-aminophenyl)maleamic acid (Santos-Sánchez et al., 2007 ▸). Compound (I) differs from related structures in the conformation of its carboxylic acid group. In (I), the –COOH group adopts syn conformation (i.e. the O3=C10—O2—H2O torsion angle = 0°) whereas an anti conformation is noted in related structures (the equivalent torsion angle is close to 180°). This disparity is a result of O—Hc⋯O=Ca (c = carboxylic acid, a = amide) intramolecular hydrogen bonds present in related structures and not observed in (I).
Figure 1.
A view of the molecular structure of (I), with displacement ellipsoids drawn at the 50% probability level.
Supramolecular features
In the crystal of (I), the molecules are connected via pairwise O2—H2O⋯O3 hydrogen bonds (Fig. 2 ▸, Table 1 ▸) forming 
(8) inversion dimers and N1—H1N⋯O1 hydrogen bonds forming C(4) chains (Fig. 2 ▸, Table 1 ▸), resulting in sheets lying in the (100) plane (Fig. 2 ▸). The N1—H1N⋯O1 hydrogen bond is reinforced by a C8—H8⋯O1 interaction forming another C(4) chain in its own right (Fig. 2 ▸, Table 1 ▸). In addition, C9—H9⋯O3 interactions (Table 1 ▸) forming C(4) chains runs down the b-axis direction, thereby cross-linking the sheets into a three-dimensional network.
Figure 2.
A view down [010] of the crystal packing in (I) showing the sheets of molecules linked by O—H⋯O and N—H⋯O hydrogen bonds and C—H⋯O interactions (thin blue lines).
Table 1. Hydrogen-bond geometry (Å, °).
| D—H⋯A | D—H | H⋯A | D⋯A | D—H⋯A |
|---|---|---|---|---|
| N1—H1N⋯O1i | 0.86 (2) | 2.15 (2) | 2.937 (3) | 153 (3) |
| O2—H2O⋯O3ii | 0.84 (2) | 1.84 (2) | 2.679 (3) | 179 (7) |
| C8—H8⋯O1i | 0.93 | 2.48 | 3.213 (3) | 136 |
| C9—H9⋯O3iii | 0.93 | 2.49 | 3.190 (4) | 133 |
Symmetry codes: (i) 
; (ii) 
; (iii) 
.
Hirshfeld surface analysis
In the Hirshfeld surface analysis, d norm surfaces and two-dimensional fingerprint plots (FP) were generated to further investigate the intermolecular interactions in (I) and to provide quantitative data for the relative contributions to the surfaces (Turner et al., 2017 ▸). The appearance of both dark- and faint-red spots near O1 and O3 support the involvement of each of these atoms in architectures involving the acceptance of a strong hydrogen bond and a weak intermolecular interaction (Fig. 3 ▸). Similarly, dark-red spots near the H1N and H2O hydrogen atoms are due to their involvement as donors in stronger hydrogen bonds, while faint spots near H8 and H9 atoms are due to the weak C—H⋯O interactions involving these atoms (Fig. 3 ▸). Analysis of the fingerprint plots (Fig. 4 ▸) showed that the major contributions to the overall Hirshfeld surfaces of (I) are from O⋯H/H⋯O (26.5%; d i + d e ∼1.8 Å), F⋯H/H⋯F (23.4%; d i + d e ∼2.6 Å), H⋯H (17.3%; d i + d e ∼2.4 Å), C⋯H/H⋯C (13.2%; d i + d e ∼3.2 Å), C⋯F/F⋯C (6.9%; d i + d e ∼3.4 Å) and F⋯F (5.5%; d i + d e ∼3.2 Å) interactions, with other contacts contributing the remaining 10.2%.
Figure 3.
The Hirshfeld surface mapped with d norm for the molecule in (I) over the range −0.753 to 1.252 a.u., shown interacting with near-neighbour molecules connected through hydrogen bonds (dashed lines).
Figure 4.
The full two-dimensional fingerprint plot and those delineated into O⋯H/H⋯O, F⋯H/H⋯F, H⋯H, C⋯H/H⋯C, C⋯F/F⋯C and F⋯F contacts in (I).
Database survey
Nineteen N-(aryl)-maleamic acids have been reported to date with varied substituents (mono-, di- and trisubstituted derivatives at different positions) on the phenyl ring. Three of these, namely N-(phenyl)maleamic acid (CCDC refcode: LOSJUZ) (Lo et al., 2009 ▸) and two o-substituted compounds, viz. N-(2-methylphenyl)maleamic acid (QUYJUQ) (Gowda et al., 2010 ▸) and N-(2-aminophenyl)maleamic acid (PILVAI) (Santos-Sánchez et al., 2007 ▸) are closely related to (I), and are therefore of most relevance to the present work. The other 16 structures are either di/tri-substituted compounds or monosubstituted ones at the meta/para positions. The nature and type of intermolecular interactions, and thereby the resulting architecture in (I) is different from those observed in the three structures, which each feature an anti O=C—O—H conformation and an intramolecular O—H⋯O hydrogen bond, as noted above. In LOSJUZ, adjacent molecules are linked by N—H⋯O hydrogen bonds into a flat ribbon, while in QUYJUQ, N—H⋯O hydrogen bonds link the molecules into zigzag chains propagating parallel to [001] and these chains are further linked into sheets by weak π–π interactions. In the crystal structure of PILVAI, symmetry-related molecules are linked by N—H⋯N hydrogen bonds, forming centrosymmetric amine–amide dimers. The dimers are linked by N—H⋯O and C—H⋯O hydrogen bonds and weak N—H⋯π and π–π interactions into a three-dimensional network.
Synthesis and crystallization
The title compound was synthesized by following the same procedure that was employed for synthesizing N-(2-methylphenyl)maleamic acid (Gowda et al., 2010 ▸). Colourless prisms of (I) were recrystallized from ethanol solution.
Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2 ▸. The carbon-bound H atoms were placed in calculated positions (C—H = 0.93 Å) and were included in the refinement in the riding-model approximation, with U iso(H) set to 1.2U eq(C). The oxygen- and nitrogen-bound H atoms were located from difference-Fourier maps and freely refined.
Table 2. Experimental details.
| Crystal data | |
| Chemical formula | C11H8F3NO3 |
| M r | 259.18 |
| Crystal system, space group | Monoclinic, P21/c |
| Temperature (K) | 293 |
| a, b, c (Å) | 16.307 (4), 7.6438 (16), 9.532 (2) |
| β (°) | 103.669 (8) |
| V (Å3) | 1154.5 (4) |
| Z | 4 |
| Radiation type | Mo Kα |
| μ (mm−1) | 0.14 |
| Crystal size (mm) | 0.22 × 0.19 × 0.17 |
| Data collection | |
| Diffractometer | Bruker APEXII CCD |
| Absorption correction | Multi-scan (SADABS; Bruker, 2009 ▸) |
| T min, T max | 0.970, 0.976 |
| No. of measured, independent and observed [I > 2σ(I)] reflections | 4213, 2598, 1690 |
| R int | 0.061 |
| (sin θ/λ)max (Å−1) | 0.650 |
| Refinement | |
| R[F 2 > 2σ(F 2)], wR(F 2), S | 0.065, 0.186, 1.03 |
| No. of reflections | 2598 |
| No. of parameters | 171 |
| No. of restraints | 2 |
| H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
| Δρmax, Δρmin (e Å−3) | 0.34, −0.26 |
Supplementary Material
Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989019006509/hb7816sup1.cif
Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989019006509/hb7816Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989019006509/hb7816Isup3.cml
CCDC reference: 1914411
Additional supporting information: crystallographic information; 3D view; checkCIF report
Acknowledgments
The authors thank the Institution of Excellence, Vijnana Bhavana, University of Mysore, Manasagangotri, Mysore, for collecting the X-ray diffraction data.
supplementary crystallographic information
Crystal data
| C11H8F3NO3 | Prism |
| Mr = 259.18 | Dx = 1.491 Mg m−3 |
| Monoclinic, P21/c | Melting point: 440 K |
| Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
| a = 16.307 (4) Å | Cell parameters from 143 reflections |
| b = 7.6438 (16) Å | θ = 3.5–27.5° |
| c = 9.532 (2) Å | µ = 0.14 mm−1 |
| β = 103.669 (8)° | T = 293 K |
| V = 1154.5 (4) Å3 | Prism, colourless |
| Z = 4 | 0.22 × 0.19 × 0.17 mm |
| F(000) = 528 |
Data collection
| Bruker APEXII CCD diffractometer | 2598 independent reflections |
| Radiation source: fine-focus sealed tube | 1690 reflections with I > 2σ(I) |
| Graphite monochromator | Rint = 0.061 |
| ω scans | θmax = 27.5°, θmin = 3.5° |
| Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −21→12 |
| Tmin = 0.970, Tmax = 0.976 | k = −9→9 |
| 4213 measured reflections | l = −12→11 |
Refinement
| Refinement on F2 | Primary atom site location: dual |
| Least-squares matrix: full | Hydrogen site location: mixed |
| R[F2 > 2σ(F2)] = 0.065 | H atoms treated by a mixture of independent and constrained refinement |
| wR(F2) = 0.186 | w = 1/[σ2(Fo2) + (0.0701P)2 + 0.4963P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.02 | (Δ/σ)max < 0.001 |
| 2598 reflections | Δρmax = 0.34 e Å−3 |
| 171 parameters | Δρmin = −0.26 e Å−3 |
| 2 restraints |
Special details
| 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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)
| x | y | z | Uiso*/Ueq | ||
| O1 | 0.34076 (13) | 0.7544 (3) | 0.73122 (17) | 0.0570 (5) | |
| O2 | 0.41280 (13) | 1.1030 (3) | 0.8624 (2) | 0.0604 (6) | |
| O3 | 0.52092 (13) | 0.9298 (3) | 0.8536 (2) | 0.0609 (5) | |
| N1 | 0.28493 (13) | 0.6788 (3) | 0.4975 (2) | 0.0475 (5) | |
| F2 | 0.15299 (15) | 0.6837 (4) | 0.2366 (2) | 0.1062 (8) | |
| F3 | 0.03339 (14) | 0.6184 (4) | 0.2675 (3) | 0.1295 (11) | |
| C1 | 0.23369 (16) | 0.5362 (3) | 0.5229 (2) | 0.0457 (6) | |
| F1 | 0.1069 (2) | 0.8137 (3) | 0.3972 (3) | 0.1357 (12) | |
| C7 | 0.33398 (15) | 0.7774 (3) | 0.6013 (2) | 0.0425 (6) | |
| C10 | 0.45863 (17) | 1.0115 (3) | 0.7934 (3) | 0.0465 (6) | |
| C9 | 0.43322 (18) | 1.0235 (4) | 0.6336 (3) | 0.0523 (7) | |
| H9 | 0.457140 | 1.113209 | 0.590732 | 0.063* | |
| C8 | 0.38002 (17) | 0.9193 (3) | 0.5470 (3) | 0.0502 (6) | |
| H8 | 0.371000 | 0.935384 | 0.447771 | 0.060* | |
| C6 | 0.26681 (18) | 0.4086 (4) | 0.6223 (3) | 0.0580 (7) | |
| H6 | 0.322621 | 0.416324 | 0.674408 | 0.070* | |
| C2 | 0.15006 (17) | 0.5244 (4) | 0.4447 (3) | 0.0546 (7) | |
| C3 | 0.1014 (2) | 0.3826 (5) | 0.4683 (4) | 0.0756 (9) | |
| H3 | 0.045544 | 0.373178 | 0.416789 | 0.091* | |
| C5 | 0.2173 (2) | 0.2686 (5) | 0.6450 (4) | 0.0761 (10) | |
| H5 | 0.239695 | 0.183177 | 0.712740 | 0.091* | |
| C11 | 0.1111 (2) | 0.6602 (5) | 0.3390 (4) | 0.0750 (9) | |
| C4 | 0.1357 (2) | 0.2570 (5) | 0.5674 (4) | 0.0861 (11) | |
| H4 | 0.102772 | 0.162430 | 0.581975 | 0.103* | |
| H1N | 0.285 (2) | 0.717 (4) | 0.413 (2) | 0.072 (10)* | |
| H2O | 0.433 (3) | 1.094 (6) | 0.952 (2) | 0.104 (14)* |
Atomic displacement parameters (Å2)
| U11 | U22 | U33 | U12 | U13 | U23 | |
| O1 | 0.0721 (13) | 0.0702 (12) | 0.0297 (8) | −0.0182 (10) | 0.0138 (8) | −0.0043 (8) |
| O2 | 0.0620 (12) | 0.0664 (13) | 0.0500 (11) | 0.0158 (10) | 0.0073 (9) | −0.0087 (10) |
| O3 | 0.0565 (12) | 0.0719 (13) | 0.0507 (10) | 0.0130 (10) | 0.0051 (9) | −0.0098 (9) |
| N1 | 0.0513 (12) | 0.0585 (13) | 0.0319 (10) | −0.0109 (10) | 0.0085 (8) | −0.0007 (10) |
| F2 | 0.0939 (16) | 0.152 (2) | 0.0649 (12) | −0.0081 (15) | 0.0031 (11) | 0.0347 (13) |
| F3 | 0.0652 (14) | 0.161 (2) | 0.136 (2) | −0.0054 (16) | −0.0303 (13) | 0.0407 (19) |
| C1 | 0.0465 (14) | 0.0539 (14) | 0.0380 (11) | −0.0066 (12) | 0.0127 (10) | −0.0059 (11) |
| F1 | 0.188 (3) | 0.0863 (17) | 0.1125 (19) | 0.0550 (19) | −0.0055 (18) | 0.0035 (15) |
| C7 | 0.0436 (13) | 0.0517 (13) | 0.0319 (11) | −0.0027 (11) | 0.0084 (9) | −0.0030 (10) |
| C10 | 0.0488 (14) | 0.0410 (12) | 0.0483 (13) | −0.0048 (11) | 0.0089 (11) | −0.0058 (11) |
| C9 | 0.0653 (17) | 0.0480 (15) | 0.0452 (13) | −0.0079 (13) | 0.0163 (12) | 0.0014 (11) |
| C8 | 0.0610 (16) | 0.0553 (15) | 0.0339 (11) | −0.0063 (13) | 0.0104 (11) | 0.0031 (11) |
| C6 | 0.0467 (15) | 0.0666 (18) | 0.0597 (16) | −0.0050 (14) | 0.0104 (12) | 0.0043 (14) |
| C2 | 0.0421 (14) | 0.0652 (17) | 0.0542 (15) | −0.0019 (13) | 0.0071 (11) | −0.0063 (14) |
| C3 | 0.0479 (16) | 0.088 (2) | 0.086 (2) | −0.0175 (17) | 0.0066 (15) | −0.003 (2) |
| C5 | 0.066 (2) | 0.071 (2) | 0.091 (2) | −0.0053 (17) | 0.0175 (17) | 0.0224 (19) |
| C11 | 0.0561 (19) | 0.093 (3) | 0.0674 (19) | −0.0018 (19) | −0.0028 (15) | 0.005 (2) |
| C4 | 0.067 (2) | 0.079 (2) | 0.112 (3) | −0.0220 (19) | 0.020 (2) | 0.014 (2) |
Geometric parameters (Å, º)
| O1—C7 | 1.230 (3) | C10—C9 | 1.483 (4) |
| O2—C10 | 1.309 (3) | C9—C8 | 1.316 (4) |
| O2—H2O | 0.845 (18) | C9—H9 | 0.9300 |
| O3—C10 | 1.215 (3) | C8—H8 | 0.9300 |
| N1—C7 | 1.346 (3) | C6—C5 | 1.388 (4) |
| N1—C1 | 1.428 (3) | C6—H6 | 0.9300 |
| N1—H1N | 0.861 (18) | C2—C3 | 1.393 (4) |
| F2—C11 | 1.328 (4) | C2—C11 | 1.481 (4) |
| F3—C11 | 1.329 (4) | C3—C4 | 1.369 (5) |
| C1—C6 | 1.378 (4) | C3—H3 | 0.9300 |
| C1—C2 | 1.394 (4) | C5—C4 | 1.365 (5) |
| F1—C11 | 1.307 (4) | C5—H5 | 0.9300 |
| C7—C8 | 1.481 (3) | C4—H4 | 0.9300 |
| C10—O2—H2O | 110 (3) | C1—C6—H6 | 119.8 |
| C7—N1—C1 | 124.9 (2) | C5—C6—H6 | 119.8 |
| C7—N1—H1N | 112 (2) | C1—C2—C3 | 119.1 (3) |
| C1—N1—H1N | 123 (2) | C1—C2—C11 | 121.8 (3) |
| C6—C1—C2 | 119.8 (2) | C3—C2—C11 | 119.1 (3) |
| C6—C1—N1 | 120.4 (2) | C4—C3—C2 | 120.1 (3) |
| C2—C1—N1 | 119.8 (2) | C4—C3—H3 | 119.9 |
| O1—C7—N1 | 123.8 (2) | C2—C3—H3 | 119.9 |
| O1—C7—C8 | 121.6 (2) | C4—C5—C6 | 119.6 (3) |
| N1—C7—C8 | 114.6 (2) | C4—C5—H5 | 120.2 |
| O3—C10—O2 | 123.4 (2) | C6—C5—H5 | 120.2 |
| O3—C10—C9 | 121.1 (2) | F1—C11—F3 | 107.1 (3) |
| O2—C10—C9 | 115.4 (2) | F1—C11—F2 | 106.2 (4) |
| C8—C9—C10 | 126.1 (2) | F3—C11—F2 | 104.4 (3) |
| C8—C9—H9 | 116.9 | F1—C11—C2 | 113.4 (3) |
| C10—C9—H9 | 116.9 | F3—C11—C2 | 112.6 (3) |
| C9—C8—C7 | 122.5 (2) | F2—C11—C2 | 112.5 (3) |
| C9—C8—H8 | 118.7 | C3—C4—C5 | 121.0 (3) |
| C7—C8—H8 | 118.7 | C3—C4—H4 | 119.5 |
| C1—C6—C5 | 120.4 (3) | C5—C4—H4 | 119.5 |
| C7—N1—C1—C6 | −48.6 (4) | C6—C1—C2—C11 | 178.7 (3) |
| C7—N1—C1—C2 | 132.6 (3) | N1—C1—C2—C11 | −2.5 (4) |
| C1—N1—C7—O1 | 0.7 (4) | C1—C2—C3—C4 | 0.0 (5) |
| C1—N1—C7—C8 | −179.1 (2) | C11—C2—C3—C4 | −178.9 (3) |
| O3—C10—C9—C8 | 92.9 (4) | C1—C6—C5—C4 | 0.6 (5) |
| O2—C10—C9—C8 | −91.3 (4) | C1—C2—C11—F1 | −63.2 (4) |
| C10—C9—C8—C7 | 3.4 (5) | C3—C2—C11—F1 | 115.7 (4) |
| O1—C7—C8—C9 | 3.0 (4) | C1—C2—C11—F3 | 175.0 (3) |
| N1—C7—C8—C9 | −177.3 (3) | C3—C2—C11—F3 | −6.1 (5) |
| C2—C1—C6—C5 | −0.1 (4) | C1—C2—C11—F2 | 57.3 (4) |
| N1—C1—C6—C5 | −178.9 (3) | C3—C2—C11—F2 | −123.8 (3) |
| C6—C1—C2—C3 | −0.2 (4) | C2—C3—C4—C5 | 0.4 (6) |
| N1—C1—C2—C3 | 178.6 (3) | C6—C5—C4—C3 | −0.7 (6) |
Hydrogen-bond geometry (Å, º)
| D—H···A | D—H | H···A | D···A | D—H···A |
| N1—H1N···O1i | 0.86 (2) | 2.15 (2) | 2.937 (3) | 153 (3) |
| O2—H2O···O3ii | 0.84 (2) | 1.84 (2) | 2.679 (3) | 179 (7) |
| C8—H8···O1i | 0.93 | 2.48 | 3.213 (3) | 136 |
| C9—H9···O3iii | 0.93 | 2.49 | 3.190 (4) | 133 |
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, −y+2, −z+2; (iii) −x+1, y+1/2, −z+3/2.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989019006509/hb7816sup1.cif
Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989019006509/hb7816Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989019006509/hb7816Isup3.cml
CCDC reference: 1914411
Additional supporting information: crystallographic information; 3D view; checkCIF report