research communications
Different classical hydrogen-bonding patterns in three salicylaldoxime derivatives, 2-HO-4-XC6H3C=NOH (X = Me, OH and MeO)
aREQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007, Porto, Portugal, bFP-ENAS-Faculdade de Ciências de Saúde, Escola Superior de Saúde da UFP, Universidade Fernando Pessoa, Rua Carlos da Maia, 296, P-4200-150 Porto, Portugal, cInstituto de Tecnologia em Fármacos e Farmanguinhos, Fundação Oswaldo Cruz, 21041-250 Rio de Janeiro, RJ, Brazil, and dDepartment of Chemistry, University of Aberdeen, Meston Walk, Old Aberdeen, AB24 3UE, Scotland
*Correspondence e-mail: jnlow111@gmail.com
The crystal structures of three salicyaldoxime compounds, namely 2-hydroxy-4-methylbenzaldehyde oxime, C8H9NO2, 1, 2,4-dihydroxybenzaldehyde oxime, C7H7NO3, 2, and 2-hydroxy-4-methoxybenzaldehyde oxime, C8H9NO3, 3, are discussed. In each compound, the hydroxyl groups are essentially coplanar with their attached phenyl group. The interplanar angles between the C=N—O moieties of the oxime unit and their attached phenyl rings are 0.08 (9), 1.08 (15) and 6.65 (15)° in 1, 2 and 3, respectively. In all three molecules, the 2-hydroxy group forms an intramolecular O—H⋯N(oxime) hydrogen bond. In compound (1), intermolecular O—H(oxime)⋯O(hydroxyl) hydrogen bonds generate R22(14) dimers, related by inversion centres. In compound 2, intermolecular O—H(oxime)⋯O(4-hydroxy) hydrogen bonds generate C9 chains along the b-axis direction, while O—H(4-hydroxyl)⋯O(2-hydroxyl) interactions form zigzag C6 spiral chains along the c-axis direction, generated by a screw axis at 1, y, 1/4: the combination of the two chains provides a bimolecular sheet running parallel to the b axis, which lies between 0–1/2 c and 1/2–1 c. In compound 3, similar C9 chains, along the b-axis direction are generated by O—H(oxime)⋯O(4-methoxy) hydrogen bonds. Further weaker, C—H⋯π (in 1), π–π (in 2) and both C—H⋯π and π–π interactions (in 3) further cement the three-dimensional structures. Hirshfeld surface and fingerprint analyses are discussed.
1. Chemical context
RCH=NOH, are found in many biologically active compounds (Abele et al., 2008; Nikitjuka & Jirgensons 2014), having a diverse range of uses including as anti-tumor agents (Martínez-Pascual et al., 2017; Qin et al., 2017; Canario et al., 2018; Huang et al., 2018), acaricidal and insecticidal agents (Dai et al., 2017), thymidine phosphorylase inhibitors (Zhao et al., 2018), anti-microbial agents (Yadav et al., 2017), bacteriocides (Kozlowska et al., 2017), anti-inflammatory agents (Mohassab et al., 2017) and in the treatment of nerve-gas poisoning (Lorke et al., 2008; Voicu et al., 2010; Katalinić et al., 2017; Radić et al., 2013). In the plant kingdom, play a vital role in metabolism (Sørensen et al., 2018). A specific interest in 2-hydroxbenzaldehyde derivatives has arisen regarding their use as ligands for metal complexation (Wood et al., 2006, 2008b).
The compounds described herein are all salicylaldoxime derivatives (2-HO-4-X-C6H3-CH=NOH) with different substituents in the 4-position, namely a methyl group, a hydroxy group and a methoxy group, respectively, in compounds, 1, 2 and 3. A frequent finding for salicylaldoxime derivatives is the formation of inversion-related R22(14) dimers, as concluded from a Cambridge Structural Database survey (CSD Version 5.39, May 2018 update; Groom et al., 2016). While the structures of many salicylaldoxime derivatives have been reported, the structures of very few compounds with an additional substituent in the 4 position are known.
Compounds 1 and 3 have been shown to have significant activity against Mycobacterium tuberculosis ATTC 27294. The full report will be published elsewhere (da Costa et al., 2018).
2. Structural commentary
There are no unusual features in the molecular structures. Compound 1 (Fig. 1) crystallizes in the monoclinic P21/n with one molecule in the Compounds 2 and 3 crystallize in the monoclinic P21/c with one molecule in the (Figs. 2 and 3), all having an oxime unit with an (E) geometry. Bond angles and bond lengths in the phenyl and oxime fragments are all in the expected ranges.
In compound 1, the hydroxyl group is essentially coplanar with its attached phenyl group [displaced by 0.020 (1) Å], while the interplanar angle between the C=NO moiety of the oxime unit and the attached phenyl rings is 0.08 (9)°. In compound 2, the hydroxyl groups lie essentially within the phenyl ring plane [O atoms deviate by −0.003 (1) and 0.006 (1) Å], while the interplanar angle between the C=NO moiety of the oxime unit and the attached phenyl rings is 1.08 (15)°. In compound 3, the interplanar angle between the C=NO moiety of the oxime unit and the attached phenyl rings is 6.65 (15)°.
In all three molecules, an intramolecular O2—H2⋯N12 hydrogen bond (Tables 1–3) forms a pseudo six-membered ring.
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3. Supramolecular features
3.1. Hydrogen Bonding
In the crystal of 1, molecules are linked by O13—H13 ⋯O2 hydrogen bonds into inversion-related R44(14) dimers (Table 1). As stated above, such dimers are the most frequently found arrangement for salicyldoxime derivatives. These R22(14), or R44(10) (via the intramolecular hydrogen bond) dimers are linked into two-molecule-wide chains, propagating in the a-axis direction by pairs of O13—H13⋯O13 hydrogen bonds, thereby creating R22(4) rings, as shown in Fig. 4. The H13⋯O13 lengths in the O13—H13⋯O13ii hydrogen bond are rather long [2.611 (16) Å] with a small angle of 100.8 (12)°. However, such data fits well with published findings for H2O2 rings: a recent CSD (Groom et al., 2016) search revealed more than 500 entries for non-solvated structures having centrosymmetric H2O2 rings with H—O—H angles of 120° or less and H⋯O distances up to the sum of the van der Waals contact radii, 2.72 Å, of oxygen and hydrogen atoms. The two-molecule-wide chains are further linked into a three-dimensional arrangement by C3—H3⋯Cgiii and C11—H11⋯ Cgiv interactions (Table 1). No π–π interactions can be identified.
Compound 2 with two hydroxyl groups, as well as the oxime moiety, produces a much more complex classical hydrogen-bonding arrangement than the one found for compound 1. The bonding arrangement in 2 can be readily considered to be composed of two elements: a C9 chain, generated from O13—H13(oxime)⋯O4(4-hydroxy)ii hydrogen bonds, propagating in the direction of the b axis, see Fig. 5, and secondly a zigzag C6 spiral chain formed from O4—H4⋯O2i hydrogen bonds, see Fig. 6. The C6 and C9 chains combine to form a bimolecular sheet running parallel to the b axis which lies between 0–½ c and ½–1 c. These sheets are further linked by moderately strong π–π stacking interactions, involving all the phenyl rings in the sheet: the Cg⋯Cg separation is 3.7242 (13) Å with a phenyl ring slippage of 1.586 Å. The lack of an R22(14) dimer in 2 is apparent and results from the preferential interaction of the oxime group with the 4-hydroxyl group rather than with the 2-hydroxy group.
In compound 3, C9 chains are generated from O13—H13⋯O41(methoxy)i hydrogen bonds, which propagate in the direction of the b axis, see Fig. 7. This chain is similar to that found in compound 2, but involving the methoxy oxygen atom O41 involved instead of the hydroxy oxygen O4. Interestingly, the parameters of the two hydrogen bonds in the chains of compound 2 and 3 are very similar. The chains in compound 3 are linked into a two-dimensional array by C11—H11⋯Cg (Table 3) and π–π interactions. The centroid–centroid separation in the π–π interaction is 3.7926 (12) Å with a phenyl ring slippage of 1.571 Å – again similar parameters are found in the interactions of compounds 2 and 3. The lack of an R22(14) dimer results from the preferential interaction of the oxime group with the 4-methoxy group rather than with the 2-hydroxy group. The C141—H14B⋯O2ii and C3—H3⋯O2iii hydrogen bonds link the molecules into centrosymmetric dimers across the centre of symmetry at (½, 0, ½). The former hydrogen bond forms R22(14) rings, and the latter R22(8) rings. These link anti-parallel C9 chains, forming a corrugated ribbon which runs parallel to the a axis.
3.2. Hirshfeld Surface Analyses
The Hirshfeld surfaces (Spackman & Jayatilaka, 2009) and two-dimensional fingerprint (FP) plots (Spackman & McKinnon, 2002) provide complementary information concerning the intermolecular interactions discussed above. The analyses were generated using CrystalExplorer3.1 (Wolff et al., 2012). The Hirshfeld surfaces mapped over dnorm for 1–3 are illustrated in Fig. 8. The intense red areas on the surfaces correspond to O⋯H close contacts. The less intense red spot on the surface of 1 relates to a O⋯O short contact. The fingerprint plots are shown in Fig. 9. The percentage contributions to the Hirshfeld surface of the various atom⋯atom contacts shown in Table 4 are derived from the fingerprint plots.
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There are some differences in the percentage of close contacts listed in Table 4 between the R22(14) dimer formed by compound 1 and the molecular chains formed by compounds 2 and 3. Thus compound 1 exhibits the highest percentage of H⋯C/ C⋯H close contacts, but no C⋯C and N⋯O/ O⋯N close contacts, unlike compounds 2 and 3, and is the only one of the three compounds to have any close O⋯O contacts, albeit a very small percentage. It has to be said that the different substituents, especially the number of hydroxyl units, and other interactions, such as C—H⋯π and π–π interactions, will have significant effects on the hydrogen-bonding.
4. Database survey
A survey of the Cambridge Structural Database (CSD Version 5.39, May 2018 update; Groom et al., 2016) of the hydrogen-bonding patterns of confirmed the invariable occurrence for salicylaldoximes, R—CH=N—OH (where R is a 2-hydroxyphenyl derivative) of the formation of intramolecular O—H⋯NO(oxime) hydrogen bonds involving the ortho hydroxyl group. In addition, this hydroxyl group is also most frequently involved in intermolecular interactions producing inversion-related R22(14) dimers (Smith et al., 2003; Wood et al., 2006, 2008b). Exceptions include MXSALO [R = 2-HO-5-MeOC6H3, producing a C5 chain from O—H(oxime)⋯O(2-hydroxyl) hydrogen bonds; Pfluger et al., 1978], YUPSOT [R = 2-HO-5-tBu-C6H3, producing a C5 chain from O—H(oxime)⋯O(2-hydroxyl) hydrogen bonds; White et al., 2015a], YUPROS [R = 2-HO-3-Me-5-(piperin-1-yl-CH2)-C6H2, producing a C9 chain from O—H(oxime)⋯N(piperinyl) hydrogen bonds; White et al., 2015b] and XUSPIL [R = 2-HO-3-(piperin-1-ylmethyl)-5-tBu-C6H2, producing a C9 chain from O—H(oxime)⋯N(piperinyl) hydrogen bonds; Forgan et al., 2010].
The compounds 2-HO-3-MeOC6H3CH=N—OH (ABULIT01–07; Forgan et al., 2007; Wood et al., 2008a) and 2-HO-3-EtOC6H3CH=N—OH (HAHGAA; Cai, 2011) both form R22(14) dimers, in contrast to the chain forming 2-HO-4-MeOC6H3CH=N—OH (this study) and 2-HO-5-MeOC6H3CH=N—OH (MXSALO; Pfluger et al., 1978) and 2-HO-5-tBuOC6H3CH=N—OH (YUPSOT; White et al., 2015a).
An earlier search (Low et al., 2010) indicated that the most frequently found hydrogen-bonding arrangements for without a 2-hydroxyphenyl group are inversion-related R22(6) dimers and C3 chains.
5. Synthesis and crystallization
The title compounds were prepared from hydroxylamine and the corresponding benzaldehyde in methanol in the presence of potassium carbonate and were recrystallized from methanol. Compound 1, m.p. 378–379 K. Compound 2, m.p. 451–452 K. Compound 3, m.p. 410–411 K.
6. details
Crystal data, data collection and structure . All hydroxyl H atoms were refined isotropically. Those attached to C atoms were refined as riding atoms with C—H = 0.95–0.98 Å and Uiso(H) = 1.2–1.5Uiso(C).
details are summarized in Table 5
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Supporting information
https://doi.org/10.1107/S2056989018013361/qm2128sup1.cif
contains datablocks 1, 2, 3, global. DOI:Structure factors: contains datablock 1. DOI: https://doi.org/10.1107/S2056989018013361/qm21281sup2.hkl
Structure factors: contains datablock 2. DOI: https://doi.org/10.1107/S2056989018013361/qm21282sup3.hkl
Structure factors: contains datablock 3. DOI: https://doi.org/10.1107/S2056989018013361/qm21283sup4.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989018013361/qm21281sup5.cml
Supporting information file. DOI: https://doi.org/10.1107/S2056989018013361/qm21282sup6.cml
Supporting information file. DOI: https://doi.org/10.1107/S2056989018013361/qm21283sup7.cml
For all structures, data collection: CrysAlis PRO (Rigaku OD, 2017); cell
CrysAlis PRO (Rigaku OD, 2017); data reduction: CrysAlis PRO (Rigaku OD, 2017); program(s) used to solve structure: OSCAIL (McArdle et al., 2004), SHELXT (Sheldrick, 2015a). Program(s) used to refine structure: OSCAIL (McArdle et al., 2004), ShelXle (Hübschle et al., 2011), SHELXL2017/1 (Sheldrick, 2015b) for (1), (2); OSCAIL (McArdle et al., 2004), ShelXle (Hübschle et al., 2011), SHELXL2017/1 (Sheldrick, 2015b) for (3). For all structures, molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: OSCAIL (McArdle et al., 2004), SHELXL2017/1 (Sheldrick, 2015b), PLATON (Spek, 2009).C8H9NO2 | F(000) = 320 |
Mr = 151.16 | Dx = 1.369 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71075 Å |
a = 6.5507 (2) Å | Cell parameters from 8222 reflections |
b = 7.2523 (2) Å | θ = 3.1–31.9° |
c = 15.5478 (4) Å | µ = 0.10 mm−1 |
β = 96.737 (3)° | T = 100 K |
V = 733.54 (4) Å3 | Plate, brown |
Z = 4 | 0.25 × 0.15 × 0.02 mm |
Rigaku FRE+ AFC12 with HyPix 6000 detector diffractometer | 1696 independent reflections |
Radiation source: Rotating Anode, Rigaku FRE+ | 1560 reflections with I > 2σ(I) |
Confocal mirrors, VHF Varimax monochromator | Rint = 0.024 |
Detector resolution: 10 pixels mm-1 | θmax = 27.5°, θmin = 2.6° |
profile data from ω–scans | h = −8→8 |
Absorption correction: multi-scan (CrysAlisPro ; Rigaku OD, 2017) | k = −9→9 |
Tmin = 0.742, Tmax = 1.000 | l = −20→20 |
16323 measured reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.032 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.100 | w = 1/[σ2(Fo2) + (0.0569P)2 + 0.1857P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max < 0.001 |
1696 reflections | Δρmax = 0.33 e Å−3 |
109 parameters | Δρmin = −0.20 e Å−3 |
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 | ||
O2 | 0.62147 (10) | 0.55213 (9) | 0.38936 (4) | 0.01715 (19) | |
H2 | 0.520 (3) | 0.516 (2) | 0.4176 (11) | 0.046 (4)* | |
O13 | 0.11027 (10) | 0.35295 (10) | 0.46255 (4) | 0.01893 (19) | |
H13 | 0.155 (2) | 0.389 (2) | 0.5139 (11) | 0.041 (4)* | |
N12 | 0.27030 (11) | 0.40720 (11) | 0.41612 (5) | 0.01501 (19) | |
C1 | 0.38496 (13) | 0.41353 (12) | 0.27677 (5) | 0.0129 (2) | |
C2 | 0.57244 (13) | 0.50209 (12) | 0.30486 (5) | 0.0131 (2) | |
C3 | 0.71163 (13) | 0.54354 (12) | 0.24671 (6) | 0.0139 (2) | |
H3 | 0.837332 | 0.603208 | 0.266799 | 0.017* | |
C4 | 0.66904 (13) | 0.49864 (12) | 0.15934 (6) | 0.0137 (2) | |
C5 | 0.48296 (14) | 0.41041 (12) | 0.13081 (6) | 0.0144 (2) | |
H5 | 0.451750 | 0.379046 | 0.071398 | 0.017* | |
C6 | 0.34460 (13) | 0.36875 (12) | 0.18861 (6) | 0.0139 (2) | |
H6 | 0.219471 | 0.308503 | 0.168196 | 0.017* | |
C11 | 0.23470 (13) | 0.36707 (12) | 0.33550 (6) | 0.0139 (2) | |
H11 | 0.110265 | 0.306989 | 0.313953 | 0.017* | |
C41 | 0.81701 (14) | 0.54974 (13) | 0.09625 (6) | 0.0173 (2) | |
H41A | 0.814596 | 0.454650 | 0.051360 | 0.026* | |
H41B | 0.956069 | 0.559362 | 0.126945 | 0.026* | |
H41C | 0.776779 | 0.668498 | 0.069346 | 0.026* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O2 | 0.0175 (3) | 0.0221 (4) | 0.0115 (3) | −0.0050 (3) | 0.0003 (2) | −0.0029 (2) |
O13 | 0.0156 (3) | 0.0260 (4) | 0.0162 (3) | −0.0046 (3) | 0.0059 (3) | −0.0030 (3) |
N12 | 0.0137 (4) | 0.0158 (4) | 0.0162 (4) | −0.0005 (3) | 0.0048 (3) | 0.0001 (3) |
C1 | 0.0133 (4) | 0.0110 (4) | 0.0141 (4) | 0.0013 (3) | 0.0009 (3) | 0.0004 (3) |
C2 | 0.0159 (4) | 0.0114 (4) | 0.0115 (4) | 0.0016 (3) | −0.0009 (3) | −0.0006 (3) |
C3 | 0.0135 (4) | 0.0124 (4) | 0.0153 (4) | −0.0004 (3) | −0.0001 (3) | 0.0000 (3) |
C4 | 0.0152 (4) | 0.0112 (4) | 0.0147 (4) | 0.0020 (3) | 0.0016 (3) | 0.0009 (3) |
C5 | 0.0166 (4) | 0.0137 (4) | 0.0124 (4) | 0.0015 (3) | −0.0009 (3) | −0.0008 (3) |
C6 | 0.0133 (4) | 0.0122 (4) | 0.0153 (4) | 0.0005 (3) | −0.0016 (3) | −0.0009 (3) |
C11 | 0.0132 (4) | 0.0118 (4) | 0.0164 (4) | 0.0007 (3) | 0.0007 (3) | −0.0005 (3) |
C41 | 0.0177 (4) | 0.0192 (4) | 0.0153 (4) | −0.0016 (3) | 0.0029 (3) | 0.0000 (3) |
O2—C2 | 1.3645 (10) | C3—H3 | 0.9500 |
O2—H2 | 0.879 (18) | C4—C5 | 1.4018 (13) |
O13—N12 | 1.3973 (9) | C4—C41 | 1.5041 (12) |
O13—H13 | 0.857 (17) | C5—C6 | 1.3826 (12) |
N12—C11 | 1.2812 (11) | C5—H5 | 0.9500 |
C1—C6 | 1.4033 (12) | C6—H6 | 0.9500 |
C1—C2 | 1.4091 (12) | C11—H11 | 0.9500 |
C1—C11 | 1.4584 (12) | C41—H41A | 0.9800 |
C2—C3 | 1.3902 (12) | C41—H41B | 0.9800 |
C3—C4 | 1.3928 (12) | C41—H41C | 0.9800 |
C2—O2—H2 | 107.2 (11) | C6—C5—C4 | 120.40 (8) |
N12—O13—H13 | 101.6 (11) | C6—C5—H5 | 119.8 |
C11—N12—O13 | 112.33 (7) | C4—C5—H5 | 119.8 |
C6—C1—C2 | 117.75 (8) | C5—C6—C1 | 121.44 (8) |
C6—C1—C11 | 119.63 (8) | C5—C6—H6 | 119.3 |
C2—C1—C11 | 122.61 (8) | C1—C6—H6 | 119.3 |
O2—C2—C3 | 118.06 (8) | N12—C11—C1 | 120.08 (8) |
O2—C2—C1 | 121.18 (8) | N12—C11—H11 | 120.0 |
C3—C2—C1 | 120.75 (8) | C1—C11—H11 | 120.0 |
C2—C3—C4 | 120.80 (8) | C4—C41—H41A | 109.5 |
C2—C3—H3 | 119.6 | C4—C41—H41B | 109.5 |
C4—C3—H3 | 119.6 | H41A—C41—H41B | 109.5 |
C3—C4—C5 | 118.86 (8) | C4—C41—H41C | 109.5 |
C3—C4—C41 | 120.51 (8) | H41A—C41—H41C | 109.5 |
C5—C4—C41 | 120.60 (8) | H41B—C41—H41C | 109.5 |
C6—C1—C2—O2 | 179.14 (7) | C3—C4—C5—C6 | −0.06 (13) |
C11—C1—C2—O2 | −1.14 (14) | C41—C4—C5—C6 | −178.02 (8) |
C6—C1—C2—C3 | 0.13 (13) | C4—C5—C6—C1 | 0.24 (14) |
C11—C1—C2—C3 | 179.86 (8) | C2—C1—C6—C5 | −0.28 (13) |
O2—C2—C3—C4 | −178.99 (7) | C11—C1—C6—C5 | 179.99 (7) |
C1—C2—C3—C4 | 0.04 (14) | O13—N12—C11—C1 | 179.95 (7) |
C2—C3—C4—C5 | −0.08 (13) | C6—C1—C11—N12 | 179.91 (8) |
C2—C3—C4—C41 | 177.88 (7) | C2—C1—C11—N12 | 0.19 (14) |
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···N12 | 0.879 (18) | 1.814 (18) | 2.6066 (10) | 149.0 (15) |
O13—H13···O2i | 0.857 (17) | 2.019 (17) | 2.8132 (9) | 153.7 (15) |
O13—H13···O13ii | 0.857 (17) | 2.611 (16) | 2.8961 (14) | 100.8 (12) |
C3—H3···Cgiii | 0.95 | 2.71 | 3.4577 (9) | 136 |
C11—H11···Cgiv | 0.95 | 2.73 | 3.4910 (9) | 138 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y+1, −z+1; (iii) −x+3/2, y+1/2, −z+1/2; (iv) −x+1/2, y−1/2, −z+1/2. |
C7H7NO3 | F(000) = 320 |
Mr = 153.14 | Dx = 1.516 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71075 Å |
a = 3.7241 (1) Å | Cell parameters from 13388 reflections |
b = 8.6902 (2) Å | θ = 1.9–32.1° |
c = 20.7570 (5) Å | µ = 0.12 mm−1 |
β = 92.501 (2)° | T = 100 K |
V = 671.12 (3) Å3 | Block, colourless |
Z = 4 | 0.20 × 0.10 × 0.05 mm |
Rigaku FRE+ AFC12 with HyPix 6000 detector diffractometer | 1537 independent reflections |
Radiation source: Rotating Anode, Rigaku FRE+ | 1482 reflections with I > 2σ(I) |
Confocal mirrors, VHF Varimax monochromator | Rint = 0.039 |
Detector resolution: 10 pixels mm-1 | θmax = 27.5°, θmin = 2.0° |
profile data from ω–scans | h = −4→4 |
Absorption correction: multi-scan (CrysAlisPro ; Rigaku OD, 2017) | k = −11→11 |
Tmin = 0.654, Tmax = 1.000 | l = −26→26 |
29482 measured reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.092 | w = 1/[σ2(Fo2) + (0.0229P)2 + 1.3357P] where P = (Fo2 + 2Fc2)/3 |
S = 0.86 | (Δ/σ)max < 0.001 |
1537 reflections | Δρmax = 0.38 e Å−3 |
113 parameters | Δρmin = −0.21 e Å−3 |
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. |
Refinement. Refined as a 2-component twin. |
x | y | z | Uiso*/Ueq | ||
O2 | 0.6604 (3) | 0.13314 (13) | 0.28983 (5) | 0.0175 (3) | |
H2 | 0.568 (7) | 0.056 (3) | 0.3130 (12) | 0.045 (7)* | |
O4 | 1.0469 (3) | 0.64910 (12) | 0.32704 (5) | 0.0167 (3) | |
H4 | 1.132 (6) | 0.639 (3) | 0.2893 (11) | 0.031 (6)* | |
O13 | 0.2536 (3) | −0.13686 (13) | 0.41952 (6) | 0.0213 (3) | |
H13 | 0.208 (7) | −0.200 (3) | 0.3880 (12) | 0.043 (7)* | |
N12 | 0.3984 (4) | −0.01346 (15) | 0.38573 (6) | 0.0161 (3) | |
C1 | 0.6052 (4) | 0.24418 (16) | 0.39524 (7) | 0.0125 (3) | |
C2 | 0.7061 (4) | 0.25485 (16) | 0.33098 (7) | 0.0129 (3) | |
C3 | 0.8530 (4) | 0.38889 (17) | 0.30720 (7) | 0.0133 (3) | |
H3 | 0.9193 | 0.3946 | 0.2636 | 0.016* | |
C4 | 0.9020 (4) | 0.51454 (17) | 0.34786 (7) | 0.0133 (3) | |
C5 | 0.8047 (4) | 0.50773 (17) | 0.41191 (7) | 0.0148 (3) | |
H5 | 0.8379 | 0.5943 | 0.4395 | 0.018* | |
C6 | 0.6596 (4) | 0.37332 (17) | 0.43460 (7) | 0.0141 (3) | |
H6 | 0.5947 | 0.3683 | 0.4783 | 0.017* | |
C11 | 0.4474 (4) | 0.10553 (17) | 0.42134 (7) | 0.0144 (3) | |
H11 | 0.3805 | 0.1034 | 0.4650 | 0.017* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O2 | 0.0273 (6) | 0.0106 (5) | 0.0150 (5) | −0.0041 (5) | 0.0047 (4) | −0.0036 (4) |
O4 | 0.0249 (6) | 0.0096 (5) | 0.0161 (5) | −0.0052 (4) | 0.0051 (4) | 0.0002 (4) |
O13 | 0.0335 (7) | 0.0110 (5) | 0.0194 (6) | −0.0095 (5) | 0.0025 (5) | 0.0019 (4) |
N12 | 0.0189 (6) | 0.0103 (6) | 0.0191 (6) | −0.0029 (5) | 0.0010 (5) | 0.0030 (5) |
C1 | 0.0127 (7) | 0.0096 (6) | 0.0151 (7) | 0.0003 (5) | 0.0005 (5) | 0.0003 (5) |
C2 | 0.0142 (7) | 0.0101 (6) | 0.0143 (7) | 0.0008 (5) | −0.0003 (5) | −0.0023 (5) |
C3 | 0.0149 (7) | 0.0123 (7) | 0.0126 (6) | 0.0003 (6) | 0.0020 (5) | 0.0000 (5) |
C4 | 0.0135 (7) | 0.0087 (6) | 0.0176 (7) | −0.0005 (5) | 0.0009 (5) | 0.0020 (5) |
C5 | 0.0180 (7) | 0.0106 (7) | 0.0158 (7) | −0.0010 (6) | 0.0015 (6) | −0.0027 (5) |
C6 | 0.0158 (7) | 0.0132 (7) | 0.0135 (7) | −0.0005 (6) | 0.0021 (5) | −0.0010 (5) |
C11 | 0.0158 (7) | 0.0117 (7) | 0.0156 (7) | −0.0003 (6) | 0.0003 (5) | 0.0019 (5) |
O2—C2 | 1.3655 (17) | C1—C11 | 1.456 (2) |
O2—H2 | 0.91 (3) | C2—C3 | 1.387 (2) |
O4—C4 | 1.3660 (17) | C3—C4 | 1.387 (2) |
O4—H4 | 0.86 (2) | C3—H3 | 0.9500 |
O13—N12 | 1.4020 (16) | C4—C5 | 1.394 (2) |
O13—H13 | 0.86 (3) | C5—C6 | 1.378 (2) |
N12—C11 | 1.280 (2) | C5—H5 | 0.9500 |
C1—C6 | 1.398 (2) | C6—H6 | 0.9500 |
C1—C2 | 1.405 (2) | C11—H11 | 0.9500 |
C2—O2—H2 | 106.5 (16) | O4—C4—C3 | 121.64 (13) |
C4—O4—H4 | 111.3 (15) | O4—C4—C5 | 117.43 (13) |
N12—O13—H13 | 99.9 (16) | C3—C4—C5 | 120.93 (14) |
C11—N12—O13 | 112.18 (13) | C6—C5—C4 | 118.93 (14) |
C6—C1—C2 | 117.65 (13) | C6—C5—H5 | 120.5 |
C6—C1—C11 | 119.85 (13) | C4—C5—H5 | 120.5 |
C2—C1—C11 | 122.50 (13) | C5—C6—C1 | 121.98 (14) |
O2—C2—C3 | 117.93 (13) | C5—C6—H6 | 119.0 |
O2—C2—C1 | 120.77 (13) | C1—C6—H6 | 119.0 |
C3—C2—C1 | 121.30 (13) | N12—C11—C1 | 120.25 (14) |
C2—C3—C4 | 119.22 (13) | N12—C11—H11 | 119.9 |
C2—C3—H3 | 120.4 | C1—C11—H11 | 119.9 |
C4—C3—H3 | 120.4 | ||
C6—C1—C2—O2 | −179.97 (14) | O4—C4—C5—C6 | −179.63 (14) |
C11—C1—C2—O2 | −0.2 (2) | C3—C4—C5—C6 | 0.3 (2) |
C6—C1—C2—C3 | −0.3 (2) | C4—C5—C6—C1 | −0.4 (2) |
C11—C1—C2—C3 | 179.41 (14) | C2—C1—C6—C5 | 0.4 (2) |
O2—C2—C3—C4 | 179.88 (13) | C11—C1—C6—C5 | −179.33 (14) |
C1—C2—C3—C4 | 0.2 (2) | O13—N12—C11—C1 | 178.31 (12) |
C2—C3—C4—O4 | 179.71 (14) | C6—C1—C11—N12 | −179.63 (14) |
C2—C3—C4—C5 | −0.2 (2) | C2—C1—C11—N12 | 0.6 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···N12 | 0.91 (3) | 1.77 (3) | 2.5899 (17) | 150 (2) |
O4—H4···O2i | 0.86 (2) | 1.85 (2) | 2.7062 (16) | 174 (2) |
O13—H13···O4ii | 0.86 (3) | 1.90 (3) | 2.7583 (16) | 171 (2) |
Symmetry codes: (i) −x+2, y+1/2, −z+1/2; (ii) x−1, y−1, z. |
C8H9NO3 | F(000) = 352 |
Mr = 167.16 | Dx = 1.467 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71075 Å |
a = 9.3591 (13) Å | Cell parameters from 1379 reflections |
b = 6.2634 (7) Å | θ = 3.3–30.2° |
c = 13.6260 (2) Å | µ = 0.11 mm−1 |
β = 108.636 (16)° | T = 100 K |
V = 756.87 (15) Å3 | Plate, colourless |
Z = 4 | 0.15 × 0.05 × 0.01 mm |
Rigaku FRE+ AFC12 with HyPix 6000 detector diffractometer | 1686 independent reflections |
Radiation source: Rotating Anode, Rigaku FRE+ | 1323 reflections with I > 2σ(I) |
Confocal mirrors, VHF Varimax monochromator | Rint = 0.060 |
Detector resolution: 10 pixels mm-1 | θmax = 27.4°, θmin = 2.3° |
profile data from ω–scans | h = −11→12 |
Absorption correction: multi-scan (CrysAlisPro; Rigaku OD, 2017) | k = −7→7 |
Tmin = 0.305, Tmax = 1.000 | l = −17→17 |
5525 measured reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.049 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.158 | w = 1/[σ2(Fo2) + (0.1063P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max < 0.001 |
1686 reflections | Δρmax = 0.26 e Å−3 |
118 parameters | Δρmin = −0.29 e Å−3 |
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 | ||
O2 | 0.63191 (14) | 0.1847 (2) | 0.42822 (9) | 0.0193 (3) | |
H2 | 0.711 (3) | 0.265 (5) | 0.423 (2) | 0.049 (7)* | |
O13 | 0.91351 (14) | 0.6293 (2) | 0.38674 (10) | 0.0228 (4) | |
H13 | 0.981 (3) | 0.524 (5) | 0.388 (2) | 0.062 (9)* | |
O41 | 0.10398 (13) | 0.30632 (19) | 0.36291 (8) | 0.0182 (3) | |
N12 | 0.78766 (16) | 0.5076 (2) | 0.38782 (11) | 0.0175 (4) | |
C1 | 0.52304 (18) | 0.5260 (3) | 0.36005 (11) | 0.0145 (4) | |
C2 | 0.51014 (18) | 0.3173 (3) | 0.39480 (11) | 0.0147 (4) | |
C3 | 0.37212 (18) | 0.2374 (3) | 0.39667 (12) | 0.0158 (4) | |
H3 | 0.365066 | 0.097118 | 0.421199 | 0.019* | |
C4 | 0.24440 (19) | 0.3667 (3) | 0.36197 (12) | 0.0150 (4) | |
C5 | 0.25337 (19) | 0.5722 (3) | 0.32479 (12) | 0.0172 (4) | |
H5 | 0.165354 | 0.657670 | 0.299366 | 0.021* | |
C6 | 0.39104 (19) | 0.6495 (3) | 0.32543 (12) | 0.0158 (4) | |
H6 | 0.397195 | 0.790761 | 0.301740 | 0.019* | |
C11 | 0.66646 (18) | 0.6195 (3) | 0.36181 (12) | 0.0157 (4) | |
H11 | 0.670249 | 0.765245 | 0.343458 | 0.019* | |
C141 | 0.0866 (2) | 0.0952 (3) | 0.39792 (14) | 0.0220 (4) | |
H14A | −0.018185 | 0.074061 | 0.395637 | 0.033* | |
H14B | 0.153667 | 0.076825 | 0.469161 | 0.033* | |
H14C | 0.112340 | −0.009659 | 0.352899 | 0.033* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O2 | 0.0191 (7) | 0.0148 (6) | 0.0240 (7) | 0.0044 (5) | 0.0068 (5) | 0.0056 (5) |
O13 | 0.0187 (6) | 0.0164 (7) | 0.0360 (8) | −0.0006 (5) | 0.0127 (5) | 0.0018 (5) |
O41 | 0.0181 (6) | 0.0152 (7) | 0.0220 (6) | 0.0002 (5) | 0.0075 (5) | 0.0021 (4) |
N12 | 0.0179 (7) | 0.0163 (8) | 0.0200 (7) | −0.0027 (5) | 0.0083 (6) | −0.0003 (5) |
C1 | 0.0200 (8) | 0.0122 (8) | 0.0122 (8) | −0.0001 (6) | 0.0062 (6) | −0.0011 (6) |
C2 | 0.0175 (8) | 0.0147 (8) | 0.0121 (7) | 0.0024 (6) | 0.0051 (6) | −0.0005 (6) |
C3 | 0.0216 (9) | 0.0118 (8) | 0.0149 (8) | 0.0013 (6) | 0.0073 (6) | 0.0007 (6) |
C4 | 0.0180 (8) | 0.0155 (9) | 0.0119 (7) | −0.0001 (6) | 0.0054 (6) | −0.0024 (6) |
C5 | 0.0204 (8) | 0.0150 (8) | 0.0160 (8) | 0.0045 (6) | 0.0055 (6) | 0.0006 (6) |
C6 | 0.0235 (9) | 0.0106 (8) | 0.0139 (8) | 0.0017 (6) | 0.0068 (6) | 0.0008 (6) |
C11 | 0.0204 (9) | 0.0131 (8) | 0.0143 (8) | 0.0004 (6) | 0.0065 (6) | −0.0004 (5) |
C141 | 0.0225 (9) | 0.0144 (9) | 0.0290 (9) | −0.0018 (7) | 0.0082 (7) | 0.0031 (7) |
O2—C2 | 1.365 (2) | C3—C4 | 1.395 (2) |
O2—H2 | 0.92 (3) | C3—H3 | 0.9500 |
O13—N12 | 1.4067 (18) | C4—C5 | 1.396 (2) |
O13—H13 | 0.91 (3) | C5—C6 | 1.374 (2) |
O41—C4 | 1.371 (2) | C5—H5 | 0.9500 |
O41—C141 | 1.432 (2) | C6—H6 | 0.9500 |
N12—C11 | 1.283 (2) | C11—H11 | 0.9500 |
C1—C2 | 1.409 (2) | C141—H14A | 0.9800 |
C1—C6 | 1.405 (2) | C141—H14B | 0.9800 |
C1—C11 | 1.458 (2) | C141—H14C | 0.9800 |
C2—C3 | 1.393 (2) | ||
C2—O2—H2 | 104.4 (17) | C6—C5—C4 | 119.18 (15) |
N12—O13—H13 | 100.6 (19) | C6—C5—H5 | 120.4 |
C4—O41—C141 | 117.95 (13) | C4—C5—H5 | 120.4 |
C11—N12—O13 | 111.75 (14) | C5—C6—C1 | 122.04 (15) |
C2—C1—C6 | 117.58 (15) | C5—C6—H6 | 119.0 |
C2—C1—C11 | 123.02 (15) | C1—C6—H6 | 119.0 |
C6—C1—C11 | 119.37 (15) | N12—C11—C1 | 120.87 (16) |
O2—C2—C3 | 117.11 (15) | N12—C11—H11 | 119.6 |
O2—C2—C1 | 121.63 (15) | C1—C11—H11 | 119.6 |
C3—C2—C1 | 121.26 (15) | O41—C141—H14A | 109.5 |
C4—C3—C2 | 118.99 (15) | O41—C141—H14B | 109.5 |
C4—C3—H3 | 120.5 | H14A—C141—H14B | 109.5 |
C2—C3—H3 | 120.5 | O41—C141—H14C | 109.5 |
O41—C4—C3 | 123.83 (15) | H14A—C141—H14C | 109.5 |
O41—C4—C5 | 115.24 (14) | H14B—C141—H14C | 109.5 |
C3—C4—C5 | 120.92 (16) | ||
C6—C1—C2—O2 | 178.92 (13) | C2—C3—C4—C5 | 0.7 (2) |
C11—C1—C2—O2 | −3.1 (2) | O41—C4—C5—C6 | 177.11 (13) |
C6—C1—C2—C3 | −1.2 (2) | C3—C4—C5—C6 | −1.9 (2) |
C11—C1—C2—C3 | 176.75 (14) | C4—C5—C6—C1 | 1.6 (2) |
O2—C2—C3—C4 | −179.21 (13) | C2—C1—C6—C5 | −0.1 (2) |
C1—C2—C3—C4 | 0.9 (2) | C11—C1—C6—C5 | −178.10 (14) |
C141—O41—C4—C3 | −2.5 (2) | O13—N12—C11—C1 | −178.61 (13) |
C141—O41—C4—C5 | 178.56 (14) | C2—C1—C11—N12 | 5.8 (2) |
C2—C3—C4—O41 | −178.25 (14) | C6—C1—C11—N12 | −176.33 (14) |
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···N12 | 0.92 (3) | 1.81 (3) | 2.6518 (19) | 152 (2) |
O13—H13···O41i | 0.91 (3) | 1.89 (3) | 2.7829 (18) | 169 (3) |
C141—H14B···O2ii | 0.98 | 2.62 | 3.412 (2) | 138 |
C3—H3···O2ii | 0.95 | 2.70 | 3.570 (2) | 154 |
C11—H11···Cgiii | 0.95 | 2.89 | 3.4524 (6) | 128 |
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y, −z+1; (iii) −x+1, y+1/2, −z+1/2. |
Compound | 1 | 2 | 3 |
H···H | 42.7 | 36.9 | 41.5 |
H···O/O···H | 21.4 | 33.8 | 27.9 |
H···C/C···H | 29.1 | 10.0 | 15.5 |
H···N/N···H | 5.4 | 2.9 | 4.1 |
C···C | – | 10.8 | 5.8 |
O···C/C···O | 1.2 | 2.2 | 3.1 |
N···O/O···N | – | 2.0 | 0.7 |
N···C/C···N | – | – | – |
O···O | 0.2 | – | – |
Acknowledgements
The authors thank the staff at the National Crystallographic Service, University of Southampton (Coles & Gale, 2012), for the data collection, help and advice.
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