research communications
of a 1:1 cocrystal of nicotinamide with 2-chloro-5-nitrobenzoic acid
aDepartment of Chemistry, Visvesvaraya National Institute of Technology, Nagpur 440 010, Maharashtra, India, bDepartment of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhauri, Bhopal 462 066, Madhya Pradesh, India, cDepartment of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Kingdom of Saudi Arabia, and dDepartment of Biotechnology and Food Technology, Durban University of Technology, Durban 4001, South Africa
*Correspondence e-mail: kvenugopala@kfu.edu.sa, sknayak@chm.vnit.ac.in
In the title 1:1 cocrystal, C7H4ClNO4·C6H6N2O, nicotinamide (NIC) and 2-chloro-5-nitrobenzoic acid (CNBA) cocrystallize with one molecule each of NIC and CNBA in the In this structure, CNBA and NIC form hydrogen bonds through O—H⋯N, N—H⋯O and C—H⋯O interactions along with N—H⋯O dimer hydrogen bonds of NIC. Further additional weak π–π interactions stabilize the molecular assembly of this cocrystal.
1. Chemical context
Nicotinamide (NIC) derivatives are used in various applications, for example, in the prevention of type 1 diabetes (Elliott et al., 1993) and nicotinamide cofactors are also used in preparative enzymatic synthesis (Chenault & Whitesides, 1987). The nicotinamide formulation has also been used for treatment in palliative radiotherapy (Horsman et al., 1993). The pharmacological result for the active pharmaceutical ingredient (API) will increase if it becomes cocrystallized with a coformer or other active component (Schultheiss & Newman, 2009; Lemmerer et al., 2010). Chlorobenzoic acid derivatives are widely used in the pharmaceutical industry. 2-Chloro-4-nitrobenzoic acid is used for immunodeficiency diseases as an antiviral and anticancer agent (Lemmerer et al., 2010). In the title compound, NIC is cocrystallized with the CNBA coformer as it acts as an excellent candidate for cocrystallization because of the hydrogen-bond acceptor and donor parts (Dragovic et al., 1995).
2. Structural commentary
The title compound CNBA–NIC (1:1) crystallizes in the monoclinic P21/c with four molecules of NIC and CNBA in the The dihedral angle between the amide plane with the mean plane of the phenyl part in NIC is 23.87 (1)°, and the dihedral angles of the carboxyl and nitro groups with the chlorophenyl ring in CNBA are 24.92 (1) and 3.56 (1)°, respectively. In the an (CNBA)O–H⋯N interaction plays a prime role in the molecular recognition of this cocrystal (Fig. 1).
3. Supramolecular features
In the and Table 1). In this cocrystal, the NIC molecule forms a dimer with itself having an R22(8) graph-set motif (Etter et al., 1990). These dimers are further connected via C—H⋯O hydrogen bonding and form a tetrameric ring with two molecules each of NIC and CNBA with R22(10) graph-set motifs (Etter et al., 1990) (Fig. 2). Furthermore, weak π–π interactions are observed for both NIC [3.68 (7) Å] and CNBA [3.73 (7) Å] which stabilize the molecular assembly along the bc plane (Fig. 3).
of the title cocrystal, a strong (CNBA)O—H⋯N(NIC) hydrogen bond and additional (NIC)N—H⋯O(CNBA) and (NIC)C—H⋯O(CNBA) hydrogen bonds are observed (Fig. 2
|
4. Hirshfeld surface analysis
To understand the role of intermolecular interactions, we have utilized the Hirshfeld surface analysis visualizing tool (Spackman & Jayatilaka, 2009). The Hirshfeld surfaces and two-dimensional fingerprint plots developed using CrystalExplorer (Version 3.1; Wolff et al., 2012) are shown in Fig. 4. The red spot on the surface represents a strong interaction through O—H⋯N and N—H⋯O hydrogen bonding, whereas the blue color represents a lack of interaction. The dnorm map of the title compound NIC·CNBA and its pure components is shown in Fig. 4, where individual molecular interactions were estimated. The fingerprint plot shows that O⋯H/H⋯O and H⋯H contribute the major part of the interaction in all compounds (Fig. 4). The O⋯H/H⋯O contact contributes 40% to the cocrystal NIC molecule (Fig. 5) and 20.5% to the pure NIC molecule (NICOAM01; Miwa et al., 1999) (Fig. 6), and H⋯H contributes 22% to the cocrystal NIC molecule and 41% to the pure NIC molecule. Similarly, O⋯H/H⋯O contacts contribute 33% to the cocrystal CNBA molecule (Fig. 7) and 36.6% to the pure CNBA molecule (CLNBZA; Ferguson & Sim, 1962) (Fig. 8), and H⋯H contributes 15.2% to the cocrystal CNBA molecule and 17.7% to the pure NIC molecule.
5. Database survey
A search for the title cocrystal in the Cambridge Structural Database (CSD, Version 5.40, update of February 2019; Groom et al., 2016) found no hits. However, searches for NIC and CNBA gave 237 and 9 hits, respectively. A search for the NIC molecule showed that the N atom on the phenyl ring forms strong O—H⋯N hydrogen bonds with a carboxyl H atom in the most of the cocrystals [ABULIU (Lou & Hu, 2011), BICQAH (Aitipamula et al., 2013), BICQEL (Aitipamula et al., 2013), BOBQUG (Zhang et al., 2013), CUYXUQ (Lemmerer & Bernstein, 2010), DINRUP (Lemmerer et al., 2013), DINSEA (Lemmerer et al., 2013), EDAPOQ (Orola & Veidis, 2009) etc]. For the CNBA search, two structures were found similar to the title compound where strong hydrogen bonding is formed by the carboxyl H atom with a pyridine N atom [AJIWIA (Gotoh & Ishida, 2009) and OCAZAT (Ishida et al., 2001)]. AJIWIA also shows halogen bonds through C—O⋯Cl bonding and forms a dimer through C—H⋯O hydrogen bonding.
6. Synthesis and crystallization
All the chemicals used for the synthesis were purchased from Alfa Aesar and used without further purification. A stock solution was prepared from an equimolar mixture of 2-chloro-5 nitrobenzoic acid (82.44 mg, 0.409 mmol) and nicotinamide (50 mg, 0.409 mmol) in a minimum amount of ethanol and made up to a volume of 10 ml. Ten different combinations of the mixture were prepared using ethanol–hexane as the solvent mixture over the ratio range 1:1 to 1:10. The mixture was kept in a 5 ml beaker and covered with parafilm, with four to five small holes in it. These solutions were allowed to evaporate slowly at room temperature (27 °C) over several days to obtain single crystals. After a few days, colourless crystals were obtained from ethanol–hexane solutions with concentration ratios of 1:10, 1:2 and 1:4. The melting point of the obtained crystal was 159.7 °C.
7. Refinement
Crystal data, data collection, and structure . All H atoms were found in a difference Fourier maps and were refind freely.
details are summarized in Table 2Supporting information
https://doi.org/10.1107/S2056989019013859/eb2025sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989019013859/eb2025Isup2.hkl
Data collection: APEX2 (Bruker, 2012); cell
SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS18 (Sheldrick, 2015); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009) and PLATON (Spek, 2009).C7H4ClNO4·C6H6N2O | Dx = 1.551 Mg m−3 |
Mr = 323.69 | Melting point: 159.7 K |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 7.4897 (1) Å | Cell parameters from 4123 reflections |
b = 26.3607 (5) Å | θ = 1.5–30.2° |
c = 7.0623 (1) Å | µ = 0.31 mm−1 |
β = 96.356 (1)° | T = 123 K |
V = 1385.77 (4) Å3 | Block, colorless |
Z = 4 | 0.28 × 0.22 × 0.15 mm |
F(000) = 664 |
Bruker Kappa APEXII DUO diffractometer | 4123 independent reflections |
Radiation source: fine-focus sealed tube | 3316 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
ω scans | θmax = 30.2°, θmin = 1.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −10→10 |
Tmin = 0.874, Tmax = 0.908 | k = −37→37 |
29950 measured reflections | l = −9→9 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | All H-atom parameters refined |
wR(F2) = 0.094 | w = 1/[σ2(Fo2) + (0.0394P)2 + 0.4303P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max < 0.001 |
4123 reflections | Δρmax = 0.30 e Å−3 |
239 parameters | Δρmin = −0.26 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. Single-crystal X-ray diffraction data were collected on a Bruker KAPPA APEX II DUO diffractometer using graphite-monochromated Mo-Kα radiation (λ = 0.71073Å)(Bruker, 2012). The data collection was performed at 153 (2) K. The temperature was monitored by an Oxford Cryostream cooling system (Oxford Cryostat). the program SAINT (Bruker, 2012) were used for cell refinement and data reduction. The data were scaled and absorption correction performed using SADABS(Bruker, 2001). The structure was solved by direct methods using SHELXS-18(Sheldrick, 2015) and refined by full-matrix least-squares methods based on F2 using SHELXL-2018/3(Sheldrick, 2015). The computing , Mercury(Macrae et al., 2008) and PLATON (Spek, 2009) were used for molecular graphics and molecular interactions. All non-hydrogen atoms were refined anisotropically. |
x | y | z | Uiso*/Ueq | ||
Cl1 | −0.18141 (5) | 0.18331 (2) | 0.33099 (6) | 0.04137 (12) | |
O2 | 0.39368 (12) | 0.16413 (3) | 0.29015 (14) | 0.0267 (2) | |
O1 | 0.87918 (13) | 0.45197 (3) | 1.35865 (13) | 0.0268 (2) | |
O5 | 0.29333 (16) | 0.39338 (4) | 0.38136 (16) | 0.0381 (3) | |
O3 | 0.16833 (14) | 0.13103 (3) | 0.43221 (14) | 0.0308 (2) | |
O4 | 0.50015 (15) | 0.34087 (4) | 0.32242 (18) | 0.0417 (3) | |
N1 | 0.87836 (15) | 0.53606 (4) | 1.29452 (16) | 0.0226 (2) | |
N2 | 0.57395 (14) | 0.41744 (4) | 0.85619 (15) | 0.0208 (2) | |
N3 | 0.34615 (16) | 0.35059 (4) | 0.35149 (16) | 0.0262 (2) | |
C6 | 0.75383 (15) | 0.50921 (4) | 0.89924 (17) | 0.0189 (2) | |
C1 | 0.83945 (15) | 0.48801 (4) | 1.24921 (17) | 0.0193 (2) | |
C2 | 0.74506 (15) | 0.47734 (4) | 1.05512 (16) | 0.0172 (2) | |
C12 | 0.21719 (17) | 0.30889 (4) | 0.35036 (17) | 0.0209 (2) | |
C4 | 0.59051 (17) | 0.44720 (5) | 0.70484 (18) | 0.0221 (2) | |
C13 | 0.28144 (16) | 0.25993 (4) | 0.35032 (17) | 0.0193 (2) | |
C5 | 0.67736 (17) | 0.49327 (5) | 0.72106 (18) | 0.0217 (2) | |
C9 | −0.02066 (17) | 0.23039 (5) | 0.34499 (19) | 0.0243 (3) | |
C3 | 0.65244 (16) | 0.43172 (4) | 1.02733 (17) | 0.0201 (2) | |
C8 | 0.16239 (16) | 0.21927 (4) | 0.35036 (16) | 0.0191 (2) | |
C10 | −0.08225 (18) | 0.28024 (5) | 0.3432 (2) | 0.0291 (3) | |
C7 | 0.24078 (17) | 0.16659 (4) | 0.36051 (17) | 0.0205 (2) | |
C11 | 0.03681 (19) | 0.32024 (5) | 0.34746 (19) | 0.0261 (3) | |
H3 | 0.639 (2) | 0.4084 (6) | 1.134 (2) | 0.022 (4)* | |
H6 | 0.813 (2) | 0.5415 (6) | 0.909 (2) | 0.022 (4)* | |
H13 | 0.404 (2) | 0.2537 (6) | 0.352 (2) | 0.028 (4)* | |
H4 | 0.540 (2) | 0.4339 (6) | 0.581 (2) | 0.025 (4)* | |
H5 | 0.691 (2) | 0.5138 (6) | 0.612 (2) | 0.026 (4)* | |
H1A | 0.947 (2) | 0.5426 (6) | 1.405 (3) | 0.035 (4)* | |
H1B | 0.850 (2) | 0.5613 (7) | 1.216 (3) | 0.038 (5)* | |
H11 | −0.006 (2) | 0.3550 (7) | 0.346 (3) | 0.040 (5)* | |
H10 | −0.208 (3) | 0.2870 (7) | 0.338 (3) | 0.042 (5)* | |
H2 | 0.462 (3) | 0.1292 (9) | 0.326 (3) | 0.074 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.02685 (18) | 0.0403 (2) | 0.0562 (3) | −0.01523 (14) | 0.00135 (15) | 0.00272 (16) |
O2 | 0.0251 (5) | 0.0190 (4) | 0.0362 (5) | 0.0037 (3) | 0.0040 (4) | 0.0050 (4) |
O1 | 0.0362 (5) | 0.0207 (4) | 0.0216 (5) | −0.0011 (4) | −0.0050 (4) | 0.0024 (3) |
O5 | 0.0529 (7) | 0.0147 (4) | 0.0430 (6) | −0.0008 (4) | −0.0109 (5) | −0.0029 (4) |
O3 | 0.0424 (6) | 0.0172 (4) | 0.0346 (5) | −0.0037 (4) | 0.0115 (4) | 0.0017 (4) |
O4 | 0.0345 (6) | 0.0268 (5) | 0.0654 (8) | −0.0094 (4) | 0.0126 (5) | 0.0039 (5) |
N1 | 0.0265 (5) | 0.0186 (5) | 0.0213 (5) | 0.0006 (4) | −0.0040 (4) | −0.0017 (4) |
N2 | 0.0211 (5) | 0.0163 (5) | 0.0243 (5) | −0.0016 (4) | −0.0008 (4) | −0.0014 (4) |
N3 | 0.0357 (6) | 0.0165 (5) | 0.0253 (6) | −0.0031 (4) | −0.0022 (4) | 0.0021 (4) |
C6 | 0.0196 (5) | 0.0151 (5) | 0.0220 (6) | −0.0004 (4) | 0.0022 (4) | −0.0009 (4) |
C1 | 0.0187 (5) | 0.0192 (6) | 0.0200 (6) | 0.0007 (4) | 0.0023 (4) | −0.0015 (4) |
C2 | 0.0167 (5) | 0.0164 (5) | 0.0184 (5) | 0.0018 (4) | 0.0015 (4) | −0.0014 (4) |
C12 | 0.0275 (6) | 0.0164 (5) | 0.0184 (6) | −0.0018 (4) | 0.0006 (4) | 0.0000 (4) |
C4 | 0.0247 (6) | 0.0197 (6) | 0.0207 (6) | 0.0010 (5) | −0.0022 (5) | −0.0025 (4) |
C13 | 0.0209 (5) | 0.0183 (5) | 0.0186 (6) | −0.0003 (4) | 0.0011 (4) | 0.0004 (4) |
C5 | 0.0268 (6) | 0.0184 (6) | 0.0194 (6) | 0.0004 (4) | 0.0006 (5) | 0.0017 (4) |
C9 | 0.0216 (6) | 0.0256 (6) | 0.0257 (6) | −0.0044 (5) | 0.0025 (5) | 0.0000 (5) |
C3 | 0.0216 (5) | 0.0173 (5) | 0.0212 (6) | −0.0002 (4) | 0.0015 (4) | 0.0001 (4) |
C8 | 0.0216 (5) | 0.0177 (5) | 0.0177 (6) | −0.0017 (4) | 0.0012 (4) | −0.0002 (4) |
C10 | 0.0217 (6) | 0.0320 (7) | 0.0335 (7) | 0.0045 (5) | 0.0027 (5) | 0.0004 (5) |
C7 | 0.0266 (6) | 0.0167 (5) | 0.0174 (6) | −0.0019 (4) | −0.0011 (4) | −0.0008 (4) |
C11 | 0.0305 (7) | 0.0218 (6) | 0.0255 (7) | 0.0061 (5) | 0.0010 (5) | −0.0004 (5) |
Cl1—C9 | 1.7244 (13) | C1—C2 | 1.4977 (16) |
O2—C7 | 1.2994 (15) | C2—C3 | 1.3913 (16) |
O2—H2 | 1.07 (2) | C12—C13 | 1.3774 (16) |
O1—C1 | 1.2399 (14) | C12—C11 | 1.3816 (18) |
O5—N3 | 1.2215 (15) | C4—C5 | 1.3766 (17) |
O3—C7 | 1.2208 (14) | C4—H4 | 0.977 (16) |
O4—N3 | 1.2209 (16) | C13—C8 | 1.3941 (16) |
N1—C1 | 1.3307 (16) | C13—H13 | 0.932 (16) |
N1—H1A | 0.901 (19) | C5—H5 | 0.957 (16) |
N1—H1B | 0.876 (18) | C9—C10 | 1.3921 (19) |
N2—C3 | 1.3383 (16) | C9—C8 | 1.3984 (17) |
N2—C4 | 1.3426 (16) | C3—H3 | 0.984 (15) |
N3—C12 | 1.4626 (16) | C8—C7 | 1.5064 (16) |
C6—C5 | 1.3887 (17) | C10—C11 | 1.379 (2) |
C6—C2 | 1.3922 (16) | C10—H10 | 0.955 (18) |
C6—H6 | 0.959 (15) | C11—H11 | 0.971 (18) |
C7—O2—H2 | 111.9 (13) | C12—C13—H13 | 120.6 (9) |
C1—N1—H1A | 118.6 (11) | C8—C13—H13 | 119.6 (9) |
C1—N1—H1B | 122.7 (12) | C4—C5—C6 | 119.08 (11) |
H1A—N1—H1B | 118.4 (16) | C4—C5—H5 | 121.5 (9) |
C3—N2—C4 | 118.98 (10) | C6—C5—H5 | 119.4 (9) |
O4—N3—O5 | 123.56 (12) | C10—C9—C8 | 121.40 (11) |
O4—N3—C12 | 118.49 (11) | C10—C9—Cl1 | 116.76 (10) |
O5—N3—C12 | 117.95 (12) | C8—C9—Cl1 | 121.80 (10) |
C5—C6—C2 | 118.89 (11) | N2—C3—C2 | 122.20 (11) |
C5—C6—H6 | 118.5 (9) | N2—C3—H3 | 116.1 (9) |
C2—C6—H6 | 122.6 (9) | C2—C3—H3 | 121.7 (9) |
O1—C1—N1 | 123.25 (11) | C13—C8—C9 | 117.65 (11) |
O1—C1—C2 | 118.88 (10) | C13—C8—C7 | 117.57 (10) |
N1—C1—C2 | 117.87 (11) | C9—C8—C7 | 124.77 (11) |
C3—C2—C6 | 118.46 (11) | C11—C10—C9 | 120.57 (12) |
C3—C2—C1 | 117.96 (10) | C11—C10—H10 | 119.3 (11) |
C6—C2—C1 | 123.47 (10) | C9—C10—H10 | 120.1 (11) |
C13—C12—C11 | 122.95 (11) | O3—C7—O2 | 124.84 (11) |
C13—C12—N3 | 118.27 (11) | O3—C7—C8 | 122.60 (11) |
C11—C12—N3 | 118.78 (11) | O2—C7—C8 | 112.54 (10) |
N2—C4—C5 | 122.26 (11) | C10—C11—C12 | 117.62 (12) |
N2—C4—H4 | 116.2 (9) | C10—C11—H11 | 120.6 (11) |
C5—C4—H4 | 121.6 (9) | C12—C11—H11 | 121.8 (11) |
C12—C13—C8 | 119.79 (11) | ||
C5—C6—C2—C3 | −2.96 (17) | C1—C2—C3—N2 | −175.60 (10) |
C5—C6—C2—C1 | 173.20 (11) | C12—C13—C8—C9 | 1.77 (17) |
O1—C1—C2—C3 | 21.57 (16) | C12—C13—C8—C7 | −176.93 (11) |
N1—C1—C2—C3 | −159.19 (11) | C10—C9—C8—C13 | −1.15 (19) |
O1—C1—C2—C6 | −154.61 (12) | Cl1—C9—C8—C13 | 176.29 (9) |
N1—C1—C2—C6 | 24.63 (17) | C10—C9—C8—C7 | 177.44 (12) |
O4—N3—C12—C13 | 11.29 (17) | Cl1—C9—C8—C7 | −5.12 (18) |
O5—N3—C12—C13 | −168.81 (12) | C8—C9—C10—C11 | −0.3 (2) |
O4—N3—C12—C11 | −168.07 (12) | Cl1—C9—C10—C11 | −177.83 (11) |
O5—N3—C12—C11 | 11.83 (17) | C13—C8—C7—O3 | 151.23 (12) |
C3—N2—C4—C5 | −3.55 (18) | C9—C8—C7—O3 | −27.36 (19) |
C11—C12—C13—C8 | −1.03 (19) | C13—C8—C7—O2 | −26.97 (15) |
N3—C12—C13—C8 | 179.64 (11) | C9—C8—C7—O2 | 154.44 (12) |
N2—C4—C5—C6 | 1.33 (19) | C9—C10—C11—C12 | 1.0 (2) |
C2—C6—C5—C4 | 1.97 (17) | C13—C12—C11—C10 | −0.4 (2) |
C4—N2—C3—C2 | 2.47 (17) | N3—C12—C11—C10 | 178.92 (12) |
C6—C2—C3—N2 | 0.78 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1 | 0.90 (2) | 2.005 (19) | 2.9004 (15) | 171.4 (14) |
N1—H1B···O3 | 0.873 (19) | 2.116 (19) | 2.9715 (14) | 166.6 (16) |
O2—H2···N2 | 1.07 (2) | 1.49 (2) | 2.5543 (13) | 172 (2) |
C3—H3···O4 | 0.986 (15) | 2.516 (15) | 3.4505 (16) | 158.2 (12) |
C4—H4···O5 | 0.979 (14) | 2.442 (15) | 3.3256 (17) | 149.9 (12) |
C5—H5···O5 | 0.956 (15) | 2.450 (16) | 3.0878 (17) | 124.0 (11) |
C6—H6···O3 | 0.959 (15) | 2.608 (15) | 3.452 (1) | 147.0 (11) |
C10—H10···O4 | 0.955 (15) | 2.599 (16) | 3.5010 (18) | 157.6 (15) |
Acknowledgements
The authors are thankful to IISER, Bhopal, for the single-crystal X-ray data collection.
Funding information
Funding for this research was provided by: National Research Foundation and Durban University of Technology, South Africa (grant Nos. 96807 and 98884), and SERB, DST India (grant No. ECR/2016/001820) for research support and instrument facilities.
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