Ethyl 2-[2-(4-oxo-4H-chromen-2-yl)phen­oxy]acetate

Goyal, N.; Do, C.; Donahue, J.P.; Mague, J.T.; Foroozesh, M.

doi:10.1107/S2414314618009938

organic compounds

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ISSN: 2414-3146

Volume 3| Part 7| July 2018| x180993

https://doi.org/10.1107/S2414314618009938

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Ethyl 2-[2-(4-oxo-4H-chromen-2-yl)phenoxy]acetate

Navneet Goyal,^a ^* Camilla Do,^a James P. Donahue,^b Joel T. Mague ^b and Maryam Foroozesh ^a

^aDepartment of Chemistry, Xavier University of Louisiana, 1 Drexel Dr., New Orleans, Louisiana 70125, USA, and ^bDepartment of Chemistry, Tulane University, 6400 Freret Street, New Orleans, Louisiana 70118-5698, USA
^*Correspondence e-mail: ngoyal@xula.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 18 May 2018; accepted 11 July 2018; online 24 July 2018)

In the title flavonoid derivative, C₁₉H₁₆O₅, the chromene portion is planar (r.m.s. deviation = 0.022 Å) with the substituents lying closely to the same plane. The dihedral angle between its mean plane and that of the benzene ring is 4.9 (1)°. This planarity is due, in part, to the presence of a strong intramolecular C—H⋯O hydrogen bond and to two weak C—H⋯O contacts. In the crystal, neighboring molecules are linked by a C—H⋯O hydrogen bond and a C—H⋯π interaction, forming chains along the a-axis direction.

Keywords: crystal structure; flavonoid derivative; chromene; hydrogen bonding; C—H⋯π(ring) interactions.

CCDC reference: 1855031

Structure description

Flavonoids comprise a family of natural compounds with variable phenolic structures that occur in plants. Naturally occurring flavonoids and their chemical derivatives exhibit a variety of pharmacological activities (Kühnau, 1976 ; Kale et al., 2008 ; Walle, 2007 ). It has been shown that biological activity can be affected by the position of the different substituents on the flavone ring. Many studies have been published suggesting that flavonoid-based molecules have therapeutic efficacy in areas such as cardiovascular diseases, cancers, and age-related diseases (Bear & Teel, 2000 ; Rice-Evans et al., 1995 ; Pandey, 2007 ). In general, flavonoids can acts as substrates, inducers, and/or inhibitors of P450 enzymes. We have previously reported synthetic flavonoids metabolized by several cytochrome P450 enzymes including P450s 1 A1, 1 A2, 1B1, 2 C9, 3 A4 and 3 A5 (Sridhar et al., 2012 ; Foroozesh et al., 1997 ).

The crystal structure of flavone itself (Waller et al., 2003 ) is quite similar to that of ethyl 2-(2-(4-oxo-4H-chrome-2-yl)phenoxy)acetate in that it occurs in P2₁2₁2₁ with a comparably shaped cell, is essentially planar, and forms π stacks along the a axis. The crystallographically characterized flavone derivatives most similar to the title compound are 2′-hydroxy flavone (Seetharaman & Rajan, 1995 ) and 2′-methoxy flavone (Wallet et al., 1990 ), both of which are also planar molecules with hydrogen bonding playing a role in enforcing the molecular conformation. Both 2′-hydroxy flavone and 2′-methoxy flavone also form columnar π stacks, but the latter molecule packs to form two distinct stacks along different directions.

In the title compound, the 10-membered bicylic moiety is planar to within 0.028 (3) Å (r.m.s. deviation of the fitted atoms = 0.022 Å), while the dihedral angle between its mean plane and that of the C10–C15 benzene ring is only 4.9 (1)°. This planarity is likely due to the intramolecular C8—H8⋯O3 hydrogen bond (Fig. 1 and Table 1). The conformation of the ester grouping may be due in part to C19—H19B⋯O2 and C8—H8⋯O5 hydrogen bonds, but since the H⋯O distances are only 0.04 and 0.08 Å less than the sum of the van der Waals radii, respectively, these interactions would be quite weak at best.

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 is the centroid of the C10–C15 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8⋯O3	0.96 (3)	2.13 (3)	2.771 (3)	122 (2)
C5—H5⋯O2	0.97 (3)	2.54 (3)	2.876 (3)	100 (2)
C11—H11⋯O1	0.97 (3)	2.26 (3)	2.631 (3)	101 (2)
C16—H16B⋯O4ⁱ	1.03 (3)	2.56 (3)	3.327 (3)	131 (2)
C16—H16A⋯Cg3ⁱⁱ	0.99 (3)	2.75 (3)	3.0449 (3)	128 (2)
Symmetry codes: (i) x-1, y, z; (ii) x+1, y, z.

Figure 1
The molecular structure of the title compound, with atom labeling and 50% probability displacement ellipsoids. The intramolecular hydrogen bond is shown by a dashed line (Table 1

In the crystal, molecules are linked by C—H⋯O hydrogen bonds, forming chains extending along the a-axis direction (Table 1 and Fig. 2). Within the chains there are also C—H⋯π interactions present (Table 1, Fig. 2).

Figure 2
A view of the crystal packing of the title compound. The C—H⋯O hydrogen bonds are shown as dashed lines, and the C—H⋯π interactions are illustrated by blue arrows for the central column of molecules (see Table 1

Synthesis and crystallization

Potassium carbonate (0.86 g, 6.291 mmol) was added to a stirred solution of flavon-2′-ol (0.500 g, 2.097 mmol) in 30 ml of acetone. The mixture was stirred for 30 min at 298 K. Bromo ethyl acetate (0.761 g, 5.24 mmol) was added slowly to the mixture. The reaction mixture was heated at 303 K overnight and then filtered and concentrated on a rotary evaporator. The crude material was then purified by flash chromatography on silica gel with ethyl acetate:hexanes (20:80, v:v) as the eluent to yield the title compound as a white solid (yield 0.652 g, 96%; m.p. 361–363 K). Colorless plate-like crystals were obtained by slow cooling of a warm solution of ethyl acetate:hexanes (2:1, v:v).

¹H NMR (300 MHz, δ, p.p.m. in CDCl₃): 8.23 (d, J = 9.1 Hz, 1H), 7.93 (d, J = 8.1 Hz, 1H), 7.68 (d, J = 7.3 Hz, 1H), 7.56–7.38 (m, 3H), 7.24 (s, 1H), 7.16 (t, J = 7.6 Hz, 1H), 6.91 (d, J = 7.7 Hz, 1H), 4.76 (s, 2H), 4.28 (q, J = 7.2 Hz, 2H), 1.31 (t, J = 7.2 Hz, 3H). ¹³C NMR (75 MHz, δ, p.p.m. in CDCl₃): 178.7, 168.1, 160.4, 156.4, 156.0, 133.5, 132.2, 129.6, 125.6, 124.9, 123.8, 121.7, 121.5, 118.0, 112.9, 112.5, 65.6, 61.6, 14.0. Anal. calcd. for C₁₉H₁₆O₅: C, 70.36; H, 4.97. Found: C, 70.55; H, 4.91.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₉H₁₆O₅
M_r	324.32
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	150
a, b, c (Å)	4.6852 (1), 17.5786 (5), 18.8573 (5)
V (Å³)	1553.07 (7)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.83
Crystal size (mm)	0.29 × 0.22 × 0.07

Data collection
Diffractometer	Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.77, 0.94
No. of measured, independent and observed [I > 2σ(I)] reflections	11308, 3030, 2800
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.089, 1.08
No. of reflections	3030
No. of parameters	281
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.17
Absolute structure	Flack x determined using 1052 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 ).
Absolute structure parameter	0.04 (9)
Computer programs: APEX3 and SAINT (Bruker, 2016 ), SHELXT (Sheldrick, 2015a ), SHELXL2018/1 (Sheldrick, 2015b ), SHELXTL (Sheldrick, 2008 ), DIAMOND (Brandenburg & Putz, 2012 ), Mercury (Macrae et al., 2008 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1855031

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314618009938/su4166sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618009938/su4166Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314618009938/su4166Isup3.cml

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/1 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2010).

Ethyl 2-[2-(4-oxo-4H-chromen-2-yl)phenoxy]acetate top

Crystal data top

C₁₉H₁₆O₅	D_x = 1.387 Mg m⁻³
M_r = 324.32	Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, P2₁2₁2₁	Cell parameters from 9900 reflections
a = 4.6852 (1) Å	θ = 3.4–72.4°
b = 17.5786 (5) Å	µ = 0.83 mm⁻¹
c = 18.8573 (5) Å	T = 150 K
V = 1553.07 (7) Å³	Plate, colourless
Z = 4	0.29 × 0.22 × 0.07 mm
F(000) = 680

Data collection top

Bruker D8 VENTURE PHOTON 100 CMOS diffractometer	3030 independent reflections
Radiation source: INCOATEC IµS micro–focus source	2800 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.040
Detector resolution: 10.4167 pixels mm^-1	θ_max = 72.4°, θ_min = 3.4°
ω scans	h = −5→4
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −21→21
T_min = 0.77, T_max = 0.94	l = −23→22
11308 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.035	All H-atom parameters refined
wR(F²) = 0.089	w = 1/[σ²(F_o²) + (0.0432P)² + 0.2094P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max < 0.001
3030 reflections	Δρ_max = 0.13 e Å⁻³
281 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Absolute structure: Flack x determined using 1052 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013).
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.04 (9)

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.2034 (3)	0.36678 (8)	0.51445 (8)	0.0368 (4)
O2	0.7780 (4)	0.46099 (10)	0.65057 (8)	0.0460 (4)
O3	0.6284 (4)	0.55035 (9)	0.41929 (8)	0.0401 (4)
O4	1.1532 (4)	0.69398 (10)	0.40606 (10)	0.0513 (5)
O5	0.9663 (4)	0.62778 (9)	0.49699 (8)	0.0423 (4)
C1	0.2302 (5)	0.33774 (12)	0.58204 (11)	0.0346 (5)
C2	0.0567 (6)	0.27625 (14)	0.59824 (13)	0.0423 (6)
H2	−0.075 (7)	0.2546 (16)	0.5610 (14)	0.049 (8)*
C3	0.0689 (6)	0.24647 (14)	0.66622 (14)	0.0474 (6)
H3	−0.056 (7)	0.2035 (18)	0.6761 (16)	0.059 (8)*
C4	0.2536 (6)	0.27732 (14)	0.71673 (13)	0.0465 (6)
H4	0.247 (7)	0.2551 (16)	0.7655 (15)	0.052 (8)*
C5	0.4281 (6)	0.33689 (14)	0.69871 (12)	0.0421 (6)
H5	0.560 (6)	0.3608 (16)	0.7313 (15)	0.047 (7)*
C6	0.4182 (5)	0.36879 (12)	0.63074 (11)	0.0350 (5)
C7	0.6005 (5)	0.43284 (12)	0.61004 (11)	0.0361 (5)
C8	0.5556 (5)	0.46043 (13)	0.53864 (12)	0.0362 (5)
H8	0.669 (6)	0.5030 (16)	0.5230 (14)	0.046 (7)*
C9	0.3641 (5)	0.42812 (12)	0.49416 (11)	0.0330 (4)
C10	0.3013 (5)	0.44765 (12)	0.41940 (11)	0.0346 (5)
C11	0.0962 (5)	0.40542 (13)	0.38233 (13)	0.0405 (5)
H11	−0.012 (6)	0.3664 (15)	0.4072 (14)	0.042 (7)*
C12	0.0415 (6)	0.41769 (14)	0.31085 (13)	0.0469 (6)
H12	−0.103 (6)	0.3856 (15)	0.2880 (15)	0.047 (7)*
C13	0.1946 (6)	0.47231 (14)	0.27468 (13)	0.0458 (6)
H13	0.159 (6)	0.4829 (16)	0.2251 (15)	0.050 (7)*
C14	0.3935 (6)	0.51654 (14)	0.30949 (12)	0.0422 (6)
H14	0.488 (7)	0.5559 (17)	0.2835 (16)	0.057 (8)*
C15	0.4429 (5)	0.50577 (12)	0.38172 (12)	0.0358 (5)
C16	0.7779 (5)	0.60771 (14)	0.38187 (12)	0.0404 (5)
H16A	0.886 (6)	0.5842 (14)	0.3420 (13)	0.041 (7)*
H16B	0.642 (6)	0.6484 (14)	0.3621 (13)	0.035 (6)*
C17	0.9869 (5)	0.64768 (13)	0.42946 (12)	0.0382 (5)
C18	1.1644 (7)	0.66578 (16)	0.54554 (14)	0.0479 (6)
H18A	1.363 (7)	0.6452 (17)	0.5326 (17)	0.058 (8)*
H18B	1.143 (6)	0.7245 (17)	0.5402 (15)	0.053 (8)*
C19	1.0807 (9)	0.64282 (19)	0.61898 (16)	0.0607 (8)
H19A	1.224 (9)	0.663 (2)	0.650 (2)	0.083 (11)*
H19B	1.074 (7)	0.588 (2)	0.6227 (17)	0.070 (10)*
H19C	0.887 (10)	0.662 (2)	0.632 (2)	0.104 (15)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0381 (8)	0.0372 (7)	0.0350 (7)	−0.0042 (7)	−0.0006 (6)	−0.0031 (6)
O2	0.0501 (10)	0.0495 (9)	0.0384 (8)	−0.0137 (8)	−0.0087 (7)	−0.0020 (7)
O3	0.0434 (9)	0.0433 (8)	0.0337 (7)	−0.0057 (7)	0.0017 (7)	−0.0005 (6)
O4	0.0484 (11)	0.0482 (9)	0.0573 (10)	−0.0074 (9)	0.0135 (9)	0.0052 (8)
O5	0.0443 (9)	0.0421 (8)	0.0405 (8)	−0.0049 (7)	0.0005 (7)	−0.0001 (7)
C1	0.0359 (12)	0.0331 (10)	0.0348 (10)	0.0033 (9)	0.0033 (9)	−0.0036 (8)
C2	0.0421 (14)	0.0389 (12)	0.0460 (12)	−0.0057 (11)	0.0030 (10)	−0.0047 (10)
C3	0.0526 (15)	0.0374 (12)	0.0523 (14)	−0.0073 (12)	0.0104 (12)	−0.0006 (10)
C4	0.0570 (16)	0.0414 (12)	0.0411 (12)	−0.0014 (12)	0.0083 (12)	0.0009 (10)
C5	0.0503 (15)	0.0403 (12)	0.0358 (11)	−0.0025 (11)	0.0031 (10)	−0.0027 (9)
C6	0.0360 (11)	0.0329 (10)	0.0362 (10)	0.0011 (10)	0.0044 (9)	−0.0050 (8)
C7	0.0377 (12)	0.0352 (11)	0.0354 (10)	−0.0004 (10)	0.0018 (9)	−0.0046 (9)
C8	0.0380 (12)	0.0350 (11)	0.0356 (11)	−0.0020 (10)	0.0010 (9)	−0.0024 (9)
C9	0.0323 (11)	0.0311 (9)	0.0355 (10)	0.0039 (9)	0.0032 (9)	−0.0037 (8)
C10	0.0352 (12)	0.0340 (10)	0.0346 (10)	0.0077 (9)	0.0001 (9)	−0.0064 (8)
C11	0.0418 (13)	0.0360 (11)	0.0437 (11)	0.0056 (10)	−0.0067 (10)	−0.0051 (10)
C12	0.0539 (16)	0.0410 (13)	0.0458 (12)	0.0095 (12)	−0.0162 (11)	−0.0092 (11)
C13	0.0551 (16)	0.0446 (13)	0.0376 (12)	0.0174 (12)	−0.0095 (11)	−0.0067 (10)
C14	0.0486 (15)	0.0434 (12)	0.0347 (11)	0.0108 (12)	−0.0010 (10)	−0.0016 (10)
C15	0.0358 (12)	0.0376 (11)	0.0340 (10)	0.0082 (10)	0.0000 (9)	−0.0070 (8)
C16	0.0405 (13)	0.0431 (12)	0.0377 (11)	0.0014 (11)	0.0083 (10)	0.0033 (10)
C17	0.0374 (12)	0.0346 (11)	0.0427 (12)	0.0060 (10)	0.0088 (10)	0.0011 (9)
C18	0.0464 (16)	0.0450 (14)	0.0523 (14)	−0.0064 (12)	−0.0055 (11)	−0.0063 (11)
C19	0.079 (2)	0.0539 (17)	0.0492 (14)	−0.0116 (16)	−0.0156 (16)	−0.0003 (13)

Geometric parameters (Å, º) top

O1—C9	1.370 (3)	C8—H8	0.96 (3)
O1—C1	1.379 (3)	C9—C10	1.481 (3)
O2—C7	1.233 (3)	C10—C11	1.401 (3)
O3—C15	1.368 (3)	C10—C15	1.410 (3)
O3—C16	1.416 (3)	C11—C12	1.389 (3)
O4—C17	1.210 (3)	C11—H11	0.97 (3)
O5—C17	1.324 (3)	C12—C13	1.379 (4)
O5—C18	1.465 (3)	C12—H12	0.98 (3)
C1—C6	1.385 (3)	C13—C14	1.380 (4)
C1—C2	1.386 (3)	C13—H13	0.97 (3)
C2—C3	1.386 (4)	C14—C15	1.394 (3)
C2—H2	1.01 (3)	C14—H14	0.96 (3)
C3—C4	1.396 (4)	C16—C17	1.503 (4)
C3—H3	0.97 (3)	C16—H16A	0.99 (3)
C4—C5	1.371 (4)	C16—H16B	1.03 (3)
C4—H4	1.00 (3)	C18—C19	1.495 (4)
C5—C6	1.400 (3)	C18—H18A	1.03 (3)
C5—H5	0.97 (3)	C18—H18B	1.04 (3)
C6—C7	1.466 (3)	C19—H19A	0.97 (4)
C7—C8	1.446 (3)	C19—H19B	0.97 (4)
C8—C9	1.353 (3)	C19—H19C	1.00 (5)

C9—O1—C1	119.97 (17)	C10—C11—H11	119.4 (16)
C15—O3—C16	117.64 (17)	C13—C12—C11	119.5 (3)
C17—O5—C18	115.8 (2)	C13—C12—H12	122.9 (16)
O1—C1—C6	121.68 (19)	C11—C12—H12	117.6 (16)
O1—C1—C2	116.0 (2)	C12—C13—C14	120.6 (2)
C6—C1—C2	122.3 (2)	C12—C13—H13	121.6 (17)
C3—C2—C1	118.3 (2)	C14—C13—H13	117.8 (17)
C3—C2—H2	121.7 (16)	C13—C14—C15	120.0 (2)
C1—C2—H2	120.0 (16)	C13—C14—H14	118.5 (19)
C2—C3—C4	120.6 (2)	C15—C14—H14	121.4 (19)
C2—C3—H3	116.4 (18)	O3—C15—C14	122.2 (2)
C4—C3—H3	122.9 (18)	O3—C15—C10	116.94 (19)
C5—C4—C3	119.8 (2)	C14—C15—C10	120.8 (2)
C5—C4—H4	123.0 (18)	O3—C16—C17	110.95 (19)
C3—C4—H4	117.1 (18)	O3—C16—H16A	109.3 (15)
C4—C5—C6	120.9 (2)	C17—C16—H16A	108.3 (15)
C4—C5—H5	123.8 (16)	O3—C16—H16B	111.7 (14)
C6—C5—H5	115.3 (16)	C17—C16—H16B	107.2 (13)
C1—C6—C5	118.1 (2)	H16A—C16—H16B	109 (2)
C1—C6—C7	119.8 (2)	O4—C17—O5	125.1 (2)
C5—C6—C7	122.1 (2)	O4—C17—C16	121.1 (2)
O2—C7—C8	122.7 (2)	O5—C17—C16	113.8 (2)
O2—C7—C6	122.4 (2)	O5—C18—C19	106.8 (2)
C8—C7—C6	114.9 (2)	O5—C18—H18A	105.4 (17)
C9—C8—C7	122.2 (2)	C19—C18—H18A	111.3 (18)
C9—C8—H8	120.0 (16)	O5—C18—H18B	109.3 (17)
C7—C8—H8	117.8 (16)	C19—C18—H18B	109.4 (16)
C8—C9—O1	121.46 (19)	H18A—C18—H18B	114 (3)
C8—C9—C10	128.7 (2)	C18—C19—H19A	107 (2)
O1—C9—C10	109.83 (18)	C18—C19—H19B	110.1 (19)
C11—C10—C15	117.1 (2)	H19A—C19—H19B	110 (3)
C11—C10—C9	119.2 (2)	C18—C19—H19C	113 (3)
C15—C10—C9	123.7 (2)	H19A—C19—H19C	111 (3)
C12—C11—C10	121.9 (3)	H19B—C19—H19C	107 (4)
C12—C11—H11	118.7 (16)

C9—O1—C1—C6	−0.3 (3)	C8—C9—C10—C11	178.7 (2)
C9—O1—C1—C2	179.21 (19)	O1—C9—C10—C11	1.5 (3)
O1—C1—C2—C3	−178.0 (2)	C8—C9—C10—C15	0.6 (4)
C6—C1—C2—C3	1.6 (4)	O1—C9—C10—C15	−176.63 (19)
C1—C2—C3—C4	−0.6 (4)	C15—C10—C11—C12	2.6 (3)
C2—C3—C4—C5	−1.0 (4)	C9—C10—C11—C12	−175.7 (2)
C3—C4—C5—C6	1.8 (4)	C10—C11—C12—C13	0.8 (4)
O1—C1—C6—C5	178.7 (2)	C11—C12—C13—C14	−2.4 (4)
C2—C1—C6—C5	−0.8 (3)	C12—C13—C14—C15	0.6 (4)
O1—C1—C6—C7	−1.7 (3)	C16—O3—C15—C14	−1.6 (3)
C2—C1—C6—C7	178.7 (2)	C16—O3—C15—C10	178.42 (19)
C4—C5—C6—C1	−0.9 (4)	C13—C14—C15—O3	−177.0 (2)
C4—C5—C6—C7	179.6 (2)	C13—C14—C15—C10	2.9 (3)
C1—C6—C7—O2	−177.6 (2)	C11—C10—C15—O3	175.58 (19)
C5—C6—C7—O2	1.9 (3)	C9—C10—C15—O3	−6.3 (3)
C1—C6—C7—C8	2.5 (3)	C11—C10—C15—C14	−4.4 (3)
C5—C6—C7—C8	−177.9 (2)	C9—C10—C15—C14	173.8 (2)
O2—C7—C8—C9	178.7 (2)	C15—O3—C16—C17	−176.01 (18)
C6—C7—C8—C9	−1.5 (3)	C18—O5—C17—O4	−0.2 (3)
C7—C8—C9—O1	−0.5 (3)	C18—O5—C17—C16	−179.5 (2)
C7—C8—C9—C10	−177.5 (2)	O3—C16—C17—O4	173.4 (2)
C1—O1—C9—C8	1.5 (3)	O3—C16—C17—O5	−7.3 (3)
C1—O1—C9—C10	179.00 (18)	C17—O5—C18—C19	173.0 (2)

Hydrogen-bond geometry (Å, º) top

Cg3 is the centroid of the C10–C15 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8···O3	0.96 (3)	2.13 (3)	2.771 (3)	122 (2)
C5—H5···O2	0.97 (3)	2.54 (3)	2.876 (3)	100 (2)
C11—H11···O1	0.97 (3)	2.26 (3)	2.631 (3)	101 (2)
C16—H16B···O4ⁱ	1.03 (3)	2.56 (3)	3.327 (3)	131 (2)
C16—H16A···Cg3ⁱⁱ	0.99 (3)	2.75 (3)	3.0449 (3)	128 (2)

Symmetry codes: (i) x−1, y, z; (ii) x+1, y, z.

Funding information

The research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health under award No. R25GM060926, NIMHD–RCMI grant No. 5 G12MD007595, and by the Louisiana Cancer Research Consortium Core Facilities at Xavier University of Louisiana. The support of NSF–MRI Grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.

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