organic compounds
3-{(E)-[(4-Formylphenyl)iminiumyl]methyl}naphthalen-2-olate
aSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my
The title Schiff base compound, C18H13NO2, is a zwitterion, with the naphthol hydroxy group deprotonated and the imine N atom protonated. It adopts an E configuration about the central C=N double bond. The dihedral angle between the naphthyl ring system and the benzene ring is 1.73 (11)°. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, adjacent molecules are connected by intermolecular C—H⋯O hydrogen bonds, forming a supramolecular ribbon along the b axis.
Related literature
For details and applications of condensation reactions, see: Alsalim et al. (2010); Wadher et al. (2009); Abou-Melha & Faruk (2008); Sondhi et al. (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536810051822/is2641sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810051822/is2641Isup2.hkl
2-Hydroxy-1-naphthaldehyde (0.172 g, 1 mmol) was added to the solution of 4-aminobenzaldehyde (0.121 g, 1mmol) in ethanol (30 ml) following which the mixture was refluxed with stirring for 1 h. The resultant orange needle-shaped single crystals suitable for X-ray
which formed was then filtered and washed with ethanolAtom H1N1 was located from a difference Fourier map and refined freely [N—H = 1.00 (3) Å]. The remaining H atoms were positioned geometrically [C—H = 0.93 Å] and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C).
Condensation reactions between
and primary have provided one of the most important and widely studied classes of chelating ligand. The ligands, usually obtained via Schiff base condensation reactions, show variations in flexibility and electronic properties (Alsalim et al., 2010). are a class of important compounds in the medicinal and pharmaceutical fields. They exhibit biological properties, including antibacterial, antifungal (Wadher et al., 2009; Abou-Melha & Faruk, 2008), anticancer, herbicidal (Wadher et al., 2009), anti-inflammatory, analgesic and kinase inhibitory activities (Sondhi et al., 2006).The ═N1 double bond [1.329 (3) Å] with the torsion angle C10-C11-N1-C12 = -179.4 (3)°. The dihedral angle between the naphthyl (C1–C10) ring system and the benzene (C12–C17) ring is 1.73 (11)°.
of the title compound is shown in Fig. 1. The molecule is a zwitterion in the crystal, with the naphthol hydroxy group deprotonated and the imine N atom protonated. It adopts an E configuration about the central C11In the
(Fig. 2), an intramolecular N1—H1N1···O1 hydrogen bonding generates an S(6) ring motif (Bernstein et al., 1995). Furthermore, the adjacent molecules are connected by intermolecular C8—H7···O2 and C17—H17A···O2 (Table 1) hydrogen bonds forming a supramolecular ribbon along the b-axis.For details and applications of condensation reactions, see: Alsalim et al. (2010); Wadher et al. (2009); Abou-Melha & Faruk (2008); Sondhi et al. (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).C18H13NO2 | F(000) = 576 |
Mr = 275.29 | Dx = 1.348 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2561 reflections |
a = 7.3685 (8) Å | θ = 3.2–30.0° |
b = 12.7437 (13) Å | µ = 0.09 mm−1 |
c = 14.4586 (15) Å | T = 296 K |
β = 91.979 (7)° | Needle, orange |
V = 1356.9 (2) Å3 | 0.86 × 0.08 × 0.07 mm |
Z = 4 |
Bruker SMART APEXII CCD area-detector diffractometer | 2394 independent reflections |
Radiation source: fine-focus sealed tube | 1416 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.054 |
φ and ω scans | θmax = 25.0°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −8→8 |
Tmin = 0.928, Tmax = 0.994 | k = −15→14 |
11574 measured reflections | l = −16→17 |
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)] = 0.064 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.171 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0799P)2 + 0.244P] where P = (Fo2 + 2Fc2)/3 |
2394 reflections | (Δ/σ)max = 0.001 |
194 parameters | Δρmax = 0.13 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C18H13NO2 | V = 1356.9 (2) Å3 |
Mr = 275.29 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.3685 (8) Å | µ = 0.09 mm−1 |
b = 12.7437 (13) Å | T = 296 K |
c = 14.4586 (15) Å | 0.86 × 0.08 × 0.07 mm |
β = 91.979 (7)° |
Bruker SMART APEXII CCD area-detector diffractometer | 2394 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 1416 reflections with I > 2σ(I) |
Tmin = 0.928, Tmax = 0.994 | Rint = 0.054 |
11574 measured reflections |
R[F2 > 2σ(F2)] = 0.064 | 0 restraints |
wR(F2) = 0.171 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | Δρmax = 0.13 e Å−3 |
2394 reflections | Δρmin = −0.23 e Å−3 |
194 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. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.6211 (3) | −0.00216 (15) | 0.67024 (13) | 0.0694 (7) | |
O2 | 0.9842 (4) | −0.31405 (18) | 0.16917 (18) | 0.0913 (8) | |
N1 | 0.7418 (3) | −0.02531 (16) | 0.50829 (17) | 0.0496 (6) | |
C1 | 0.6323 (4) | 0.0967 (2) | 0.65940 (19) | 0.0527 (7) | |
C2 | 0.5864 (4) | 0.1658 (2) | 0.73351 (19) | 0.0578 (8) | |
H2 | 0.5496 | 0.1373 | 0.7890 | 0.069* | |
C3 | 0.5952 (4) | 0.2702 (2) | 0.72465 (19) | 0.0563 (8) | |
H3 | 0.5634 | 0.3119 | 0.7743 | 0.068* | |
C4 | 0.6515 (4) | 0.3201 (2) | 0.64209 (19) | 0.0503 (7) | |
C5 | 0.6622 (4) | 0.4289 (2) | 0.6367 (2) | 0.0673 (9) | |
H4 | 0.6302 | 0.4692 | 0.6872 | 0.081* | |
C6 | 0.7185 (5) | 0.4774 (2) | 0.5590 (2) | 0.0804 (11) | |
H5 | 0.7255 | 0.5502 | 0.5564 | 0.096* | |
C7 | 0.7654 (5) | 0.4169 (2) | 0.4837 (2) | 0.0752 (10) | |
H6 | 0.8034 | 0.4496 | 0.4302 | 0.090* | |
C8 | 0.7564 (4) | 0.3100 (2) | 0.4871 (2) | 0.0587 (8) | |
H7 | 0.7884 | 0.2712 | 0.4356 | 0.070* | |
C9 | 0.7000 (3) | 0.25724 (19) | 0.56633 (17) | 0.0450 (7) | |
C10 | 0.6907 (3) | 0.14332 (19) | 0.57427 (17) | 0.0448 (7) | |
C11 | 0.7430 (3) | 0.07881 (19) | 0.50285 (18) | 0.0463 (7) | |
H11A | 0.7807 | 0.1098 | 0.4485 | 0.056* | |
C12 | 0.7929 (3) | −0.09668 (18) | 0.44023 (18) | 0.0440 (7) | |
C13 | 0.7754 (4) | −0.20274 (19) | 0.46048 (19) | 0.0524 (7) | |
H13A | 0.7329 | −0.2236 | 0.5175 | 0.063* | |
C14 | 0.8209 (4) | −0.2768 (2) | 0.39614 (19) | 0.0537 (7) | |
H14A | 0.8092 | −0.3476 | 0.4104 | 0.064* | |
C15 | 0.8834 (3) | −0.24824 (19) | 0.31103 (18) | 0.0455 (7) | |
C16 | 0.9013 (4) | −0.1417 (2) | 0.29133 (19) | 0.0534 (7) | |
H16A | 0.9443 | −0.1212 | 0.2344 | 0.064* | |
C17 | 0.8566 (4) | −0.0671 (2) | 0.35455 (18) | 0.0513 (7) | |
H17A | 0.8688 | 0.0037 | 0.3403 | 0.062* | |
C18 | 0.9279 (4) | −0.3289 (2) | 0.2450 (2) | 0.0625 (8) | |
H18A | 0.9115 | −0.3982 | 0.2629 | 0.075* | |
H1N1 | 0.698 (4) | −0.048 (2) | 0.570 (2) | 0.086 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0902 (17) | 0.0565 (13) | 0.0634 (14) | 0.0048 (11) | 0.0285 (12) | 0.0080 (10) |
O2 | 0.116 (2) | 0.0838 (16) | 0.0757 (17) | −0.0014 (13) | 0.0242 (15) | −0.0122 (12) |
N1 | 0.0528 (15) | 0.0482 (14) | 0.0486 (15) | 0.0021 (10) | 0.0130 (12) | −0.0011 (11) |
C1 | 0.0472 (18) | 0.0561 (18) | 0.0552 (18) | 0.0041 (13) | 0.0085 (14) | 0.0025 (14) |
C2 | 0.0542 (19) | 0.074 (2) | 0.0461 (17) | −0.0002 (15) | 0.0125 (14) | −0.0011 (14) |
C3 | 0.053 (2) | 0.065 (2) | 0.0511 (18) | 0.0029 (14) | 0.0072 (15) | −0.0126 (14) |
C4 | 0.0432 (17) | 0.0557 (17) | 0.0520 (17) | 0.0027 (12) | 0.0037 (14) | −0.0088 (13) |
C5 | 0.080 (2) | 0.0574 (19) | 0.065 (2) | 0.0052 (15) | 0.0082 (18) | −0.0145 (15) |
C6 | 0.115 (3) | 0.0487 (18) | 0.078 (2) | 0.0010 (17) | 0.016 (2) | −0.0039 (17) |
C7 | 0.104 (3) | 0.055 (2) | 0.068 (2) | 0.0024 (17) | 0.0191 (19) | 0.0091 (16) |
C8 | 0.072 (2) | 0.0506 (18) | 0.0543 (18) | 0.0065 (14) | 0.0099 (16) | −0.0014 (13) |
C9 | 0.0373 (16) | 0.0488 (15) | 0.0487 (16) | 0.0020 (11) | 0.0018 (13) | −0.0020 (12) |
C10 | 0.0379 (16) | 0.0494 (16) | 0.0475 (16) | 0.0032 (11) | 0.0058 (13) | −0.0001 (12) |
C11 | 0.0440 (16) | 0.0482 (16) | 0.0470 (16) | 0.0035 (12) | 0.0053 (13) | 0.0025 (12) |
C12 | 0.0374 (16) | 0.0447 (15) | 0.0500 (17) | 0.0019 (11) | 0.0053 (13) | −0.0008 (12) |
C13 | 0.0563 (19) | 0.0534 (17) | 0.0479 (16) | 0.0013 (13) | 0.0088 (14) | 0.0058 (13) |
C14 | 0.0603 (19) | 0.0427 (15) | 0.0581 (18) | 0.0008 (12) | 0.0048 (15) | −0.0005 (13) |
C15 | 0.0385 (16) | 0.0478 (15) | 0.0501 (17) | 0.0002 (12) | 0.0022 (13) | −0.0032 (12) |
C16 | 0.0525 (19) | 0.0583 (18) | 0.0500 (17) | −0.0030 (13) | 0.0124 (14) | −0.0004 (13) |
C17 | 0.0570 (18) | 0.0440 (15) | 0.0539 (17) | −0.0007 (12) | 0.0152 (14) | 0.0032 (12) |
C18 | 0.071 (2) | 0.0581 (18) | 0.059 (2) | −0.0023 (15) | 0.0134 (17) | −0.0067 (14) |
O1—C1 | 1.272 (3) | C7—H6 | 0.9300 |
O2—C18 | 1.201 (3) | C8—C9 | 1.404 (4) |
N1—C11 | 1.329 (3) | C8—H7 | 0.9300 |
N1—C12 | 1.401 (3) | C9—C10 | 1.458 (3) |
N1—H1N1 | 1.00 (3) | C10—C11 | 1.385 (3) |
C1—C2 | 1.437 (4) | C11—H11A | 0.9300 |
C1—C10 | 1.446 (3) | C12—C13 | 1.390 (3) |
C2—C3 | 1.338 (4) | C12—C17 | 1.392 (3) |
C2—H2 | 0.9300 | C13—C14 | 1.374 (4) |
C3—C4 | 1.427 (4) | C13—H13A | 0.9300 |
C3—H3 | 0.9300 | C14—C15 | 1.378 (4) |
C4—C5 | 1.390 (4) | C14—H14A | 0.9300 |
C4—C9 | 1.413 (3) | C15—C16 | 1.394 (3) |
C5—C6 | 1.359 (4) | C15—C18 | 1.448 (4) |
C5—H4 | 0.9300 | C16—C17 | 1.367 (3) |
C6—C7 | 1.389 (4) | C16—H16A | 0.9300 |
C6—H5 | 0.9300 | C17—H17A | 0.9300 |
C7—C8 | 1.364 (4) | C18—H18A | 0.9300 |
C11—N1—C12 | 127.2 (2) | C4—C9—C10 | 119.3 (2) |
C11—N1—H1N1 | 110.3 (17) | C11—C10—C1 | 119.3 (2) |
C12—N1—H1N1 | 122.6 (17) | C11—C10—C9 | 121.2 (2) |
O1—C1—C2 | 119.8 (2) | C1—C10—C9 | 119.5 (2) |
O1—C1—C10 | 122.3 (2) | N1—C11—C10 | 123.1 (2) |
C2—C1—C10 | 117.9 (2) | N1—C11—H11A | 118.5 |
C3—C2—C1 | 121.7 (3) | C10—C11—H11A | 118.5 |
C3—C2—H2 | 119.2 | C13—C12—C17 | 119.2 (2) |
C1—C2—H2 | 119.2 | C13—C12—N1 | 117.0 (2) |
C2—C3—C4 | 122.7 (3) | C17—C12—N1 | 123.8 (2) |
C2—C3—H3 | 118.7 | C14—C13—C12 | 119.9 (2) |
C4—C3—H3 | 118.7 | C14—C13—H13A | 120.1 |
C5—C4—C9 | 120.3 (3) | C12—C13—H13A | 120.1 |
C5—C4—C3 | 120.7 (3) | C13—C14—C15 | 121.4 (2) |
C9—C4—C3 | 119.0 (2) | C13—C14—H14A | 119.3 |
C6—C5—C4 | 121.3 (3) | C15—C14—H14A | 119.3 |
C6—C5—H4 | 119.3 | C14—C15—C16 | 118.4 (2) |
C4—C5—H4 | 119.3 | C14—C15—C18 | 119.5 (2) |
C5—C6—C7 | 119.1 (3) | C16—C15—C18 | 122.1 (3) |
C5—C6—H5 | 120.5 | C17—C16—C15 | 120.9 (2) |
C7—C6—H5 | 120.5 | C17—C16—H16A | 119.5 |
C8—C7—C6 | 120.9 (3) | C15—C16—H16A | 119.5 |
C8—C7—H6 | 119.6 | C16—C17—C12 | 120.2 (2) |
C6—C7—H6 | 119.6 | C16—C17—H17A | 119.9 |
C7—C8—C9 | 121.6 (3) | C12—C17—H17A | 119.9 |
C7—C8—H7 | 119.2 | O2—C18—C15 | 125.7 (3) |
C9—C8—H7 | 119.2 | O2—C18—H18A | 117.2 |
C8—C9—C4 | 116.8 (2) | C15—C18—H18A | 117.2 |
C8—C9—C10 | 123.9 (2) | ||
O1—C1—C2—C3 | −179.6 (3) | C4—C9—C10—C11 | −177.8 (2) |
C10—C1—C2—C3 | 0.6 (4) | C8—C9—C10—C1 | 179.4 (3) |
C1—C2—C3—C4 | −0.4 (4) | C4—C9—C10—C1 | −0.1 (3) |
C2—C3—C4—C5 | −178.7 (3) | C12—N1—C11—C10 | −179.6 (2) |
C2—C3—C4—C9 | 0.0 (4) | C1—C10—C11—N1 | 0.2 (4) |
C9—C4—C5—C6 | 0.2 (5) | C9—C10—C11—N1 | 177.9 (2) |
C3—C4—C5—C6 | 178.9 (3) | C11—N1—C12—C13 | −178.2 (2) |
C4—C5—C6—C7 | 0.3 (5) | C11—N1—C12—C17 | 0.8 (4) |
C5—C6—C7—C8 | −0.3 (5) | C17—C12—C13—C14 | 0.0 (4) |
C6—C7—C8—C9 | −0.1 (5) | N1—C12—C13—C14 | 179.1 (2) |
C7—C8—C9—C4 | 0.6 (4) | C12—C13—C14—C15 | −0.3 (4) |
C7—C8—C9—C10 | −179.0 (3) | C13—C14—C15—C16 | 0.5 (4) |
C5—C4—C9—C8 | −0.6 (4) | C13—C14—C15—C18 | −179.4 (3) |
C3—C4—C9—C8 | −179.3 (2) | C14—C15—C16—C17 | −0.5 (4) |
C5—C4—C9—C10 | 178.9 (2) | C18—C15—C16—C17 | 179.3 (3) |
C3—C4—C9—C10 | 0.2 (4) | C15—C16—C17—C12 | 0.3 (4) |
O1—C1—C10—C11 | −2.4 (4) | C13—C12—C17—C16 | 0.0 (4) |
C2—C1—C10—C11 | 177.4 (2) | N1—C12—C17—C16 | −179.1 (2) |
O1—C1—C10—C9 | 179.8 (2) | C14—C15—C18—O2 | −179.6 (3) |
C2—C1—C10—C9 | −0.3 (4) | C16—C15—C18—O2 | 0.5 (5) |
C8—C9—C10—C11 | 1.7 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O1 | 1.00 (3) | 1.68 (3) | 2.551 (3) | 143 (2) |
C8—H7···O2i | 0.93 | 2.54 | 3.399 (4) | 153 |
C17—H17A···O2i | 0.93 | 2.57 | 3.453 (4) | 159 |
Symmetry code: (i) −x+2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C18H13NO2 |
Mr | 275.29 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 7.3685 (8), 12.7437 (13), 14.4586 (15) |
β (°) | 91.979 (7) |
V (Å3) | 1356.9 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.86 × 0.08 × 0.07 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.928, 0.994 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11574, 2394, 1416 |
Rint | 0.054 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.064, 0.171, 1.04 |
No. of reflections | 2394 |
No. of parameters | 194 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.13, −0.23 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O1 | 1.00 (3) | 1.68 (3) | 2.551 (3) | 143 (2) |
C8—H7···O2i | 0.93 | 2.54 | 3.399 (4) | 153 |
C17—H17A···O2i | 0.93 | 2.57 | 3.453 (4) | 159 |
Symmetry code: (i) −x+2, y+1/2, −z+1/2. |
Acknowledgements
AMF, SGT and HO thank the Malaysian Government and Universiti Sains Malaysia for the RU research grant (815002). AMF also thanks the Libyan Government for providing a scholarship. HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.
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Condensation reactions between carbonyl compounds and primary amines have provided one of the most important and widely studied classes of chelating ligand. The ligands, usually obtained via Schiff base condensation reactions, show variations in flexibility and electronic properties (Alsalim et al., 2010). Schiff bases are a class of important compounds in the medicinal and pharmaceutical fields. They exhibit biological properties, including antibacterial, antifungal (Wadher et al., 2009; Abou-Melha & Faruk, 2008), anticancer, herbicidal (Wadher et al., 2009), anti-inflammatory, analgesic and kinase inhibitory activities (Sondhi et al., 2006).
The asymmetric unit of the title compound is shown in Fig. 1. The molecule is a zwitterion in the crystal, with the naphthol hydroxy group deprotonated and the imine N atom protonated. It adopts an E configuration about the central C11═N1 double bond [1.329 (3) Å] with the torsion angle C10-C11-N1-C12 = -179.4 (3)°. The dihedral angle between the naphthyl (C1–C10) ring system and the benzene (C12–C17) ring is 1.73 (11)°.
In the crystal structure (Fig. 2), an intramolecular N1—H1N1···O1 hydrogen bonding generates an S(6) ring motif (Bernstein et al., 1995). Furthermore, the adjacent molecules are connected by intermolecular C8—H7···O2 and C17—H17A···O2 (Table 1) hydrogen bonds forming a supramolecular ribbon along the b-axis.