Ethyl 9-fluoro-5,12-dioxo-5,12-dihydro­indolizino[2,3-g]quinoline-6-carboxyl­ate

Zhang, D.-L.; Zhang, L.-P.; Yao, J.; Wu, X.-W.; An, L.-K.

doi:10.1107/S160053681202692X

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 8| August 2012| Page o2548

https://doi.org/10.1107/S160053681202692X

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Ethyl 9-fluoro-5,12-dioxo-5,12-dihydroindolizino[2,3-g]quinoline-6-carboxylate

Da-Li Zhang,^a Li-Ping Zhang,^a Jia Yao,^b Xi-Wei Wu ^a and Lin-Kun An ^a ^*

^aSchool of Pharmaceutical Science, Sun Yat-Sen University, Guangzhou 510006, People's Republic of China, and ^bSchool of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China
^*Correspondence e-mail: lssalk@mail.sysu.edu.cn

(Received 4 June 2012; accepted 14 June 2012; online 25 July 2012)

In the title molecule, C₁₈H₁₁FN₂O₄, the fused four- ring system is essentially planar, with an r.m.s. deviation of 0.032 Å. In the crystal, molecules are connected by π–π stacking interactions [centroid–centroid distances = 3.5684 (9) and 3.8247 (9) Å] into chains along [100].

Related literature

The title compound was obtained in an attempt to synthesize a Top1 (DNA topoisomerase IB) inhibitor. For general background to Top1, see: Pommier (2006 ). For the synthesis, see: Shen et al. (2008 ); Cheng et al. (2008 ). For a related structure, see: Wu et al. (2011 ). For the Top1 inhibitory activity of a related indolizinoquinoline-5,12-dione derivative, see: Wu et al. (2010 ).

Experimental

Crystal data

C₁₈H₁₁FN₂O₄
M_r = 338.29
Monoclinic, P 2₁ /c
a = 6.85562 (10) Å
b = 12.12898 (16) Å
c = 17.0304 (2) Å
β = 94.2306 (13)°
V = 1412.25 (3) Å³
Z = 4
Cu Kα radiation
μ = 1.04 mm⁻¹
T = 136 K
0.30 × 0.20 × 0.20 mm

Data collection

Agilent Xcalibur Onyx Nova diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ) T_min = 0.550, T_max = 1.000
5740 measured reflections
2723 independent reflections
2278 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.101
S = 1.08
2723 reflections
270 parameters
All H-atom parameters refined
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis RED (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053681202692X/lh5489sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053681202692X/lh5489Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S160053681202692X/lh5489Isup3.cml

checkCIF report

Comment top

Top1 is an essential nuclear enzyme, and can be used as a target to discover anticancer agents (Pommier, 2006). In our previous research, we found ethyl 7-fluoro-5,12-dioxo-5,12-dihydroindolizino[2,3-g] quinoline-6-carboxylate is a strong Top1 inhibitor with a different inhibitory mechanism from camptothecin, a well known Top1 inhibitor (Wu et al. 2010). In order to investigate the Top1 inhibitory activity of the 9-fluoro substituted isomer, the title compound was synthesized according to a modified literature method (Shen et al. 2008; Cheng et al. 2008; Wu et al. 2011) and its crystal structure was determined.

The asymmetric unit of the title compound is shown in figure 1. In the molecule the four fused aromatic rings system is approximately planar with an r.m.s. deviation = 0.032 Å. In the crystal, molecules are connected by π–π stacking interactions to form chains along [100]. Cg1···Cg1ⁱ = 3.5684 (9)Å and Cg1···Cg4ⁱⁱ = 3.8247 (9) Å, where Cg1 and Cg2 are the centroids of the N2/C8/C7/C6/C13 and C4/C5/C6/C13/C14/C15 rings [symmetry codes: (i) -x, 1-y, 1-z, (ii) 1-x, 1-y, 1-z].

Related literature top

The title compound was obtained in an attempt to synthesize a Top1 (DNA topoisomerase IB) inhibitor. For general background to Top1, see: Pommier (2006). For the synthesis, see: Shen et al. (2008); Cheng et al. (2008). For a related structure, see: Wu et al. (2011). For the Top1 inhibitory activity of a related indolizinoquinoline-5,12-dione derivative, see: Wu et al. (2010).

Experimental top

According to a modified literature method (Shen et al., 2008; Cheng et al., 2008; Wu et al., 2011), 12 equivalents of 3-fluoropyridine reacted with 6,7-dichloroquinoline-5,8-dione and ethyl acetoacetate to give the title compound as orange solid. Needle-shaped crystals suitable for X-ray analysis were obtained by slow evaporation of a solution of the title compound in chloroform-ethyl acetate (20/1, v/v).

Structure description top

The title compound was obtained in an attempt to synthesize a Top1 (DNA topoisomerase IB) inhibitor. For general background to Top1, see: Pommier (2006). For the synthesis, see: Shen et al. (2008); Cheng et al. (2008). For a related structure, see: Wu et al. (2011). For the Top1 inhibitory activity of a related indolizinoquinoline-5,12-dione derivative, see: Wu et al. (2010).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis RED (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

Fig. 1. The molecular structure of the title compound. The displacement ellipsoids are at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.

Ethyl 9-fluoro-5,12-dioxo-5,12-dihydroindolizino[2,3-g]quinoline-6-carboxylate top

Crystal data top

C₁₈H₁₁FN₂O₄	F(000) = 696
M_r = 338.29	D_x = 1.591 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.5418 Å
Hall symbol: -P 2ybc	Cell parameters from 3543 reflections
a = 6.85562 (10) Å	θ = 2.6–72.7°
b = 12.12898 (16) Å	µ = 1.04 mm⁻¹
c = 17.0304 (2) Å	T = 136 K
β = 94.2306 (13)°	Needle, orange
V = 1412.25 (3) Å³	0.30 × 0.20 × 0.20 mm
Z = 4

Data collection top

Agilent Xcalibur Onyx Nova diffractometer	2723 independent reflections
Radiation source: Nova (Cu) X-ray Source	2278 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.025
Detector resolution: 8.2417 pixels mm^-1	θ_max = 72.9°, θ_min = 5.2°
ω scans	h = −8→8
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −14→10
T_min = 0.550, T_max = 1.000	l = −20→20
5740 measured reflections

Refinement top

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.101	All H-atom parameters refined
S = 1.08	w = 1/[σ²(F_o²) + (0.0396P)² + 0.8533P] where P = (F_o² + 2F_c²)/3
2723 reflections	(Δ/σ)_max = 0.001
270 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₈H₁₁FN₂O₄	V = 1412.25 (3) Å³
M_r = 338.29	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 6.85562 (10) Å	µ = 1.04 mm⁻¹
b = 12.12898 (16) Å	T = 136 K
c = 17.0304 (2) Å	0.30 × 0.20 × 0.20 mm
β = 94.2306 (13)°

Data collection top

Agilent Xcalibur Onyx Nova diffractometer	2723 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	2278 reflections with I > 2σ(I)
T_min = 0.550, T_max = 1.000	R_int = 0.025
5740 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.101	All H-atom parameters refined
S = 1.08	Δρ_max = 0.30 e Å⁻³
2723 reflections	Δρ_min = −0.24 e Å⁻³
270 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
F1	0.02823 (18)	0.90196 (9)	0.34624 (7)	0.0382 (3)
O2	0.28727 (18)	0.79052 (10)	0.60332 (7)	0.0266 (3)
O3	0.1029 (2)	0.36760 (11)	0.33751 (7)	0.0301 (3)
O1	0.3911 (2)	0.34756 (10)	0.58977 (7)	0.0307 (3)
N1	0.4460 (2)	0.68373 (12)	0.73454 (9)	0.0241 (3)
O4	0.2439 (2)	0.28907 (10)	0.44611 (8)	0.0291 (3)
C4	0.4124 (2)	0.51043 (14)	0.66509 (10)	0.0199 (4)
N2	0.1785 (2)	0.66666 (11)	0.45980 (8)	0.0195 (3)
C13	0.2564 (2)	0.62440 (14)	0.53105 (10)	0.0192 (4)
C6	0.2735 (2)	0.51065 (14)	0.52314 (10)	0.0193 (4)
C16	0.1782 (2)	0.37539 (14)	0.40402 (10)	0.0204 (4)
C14	0.3084 (2)	0.68974 (14)	0.60029 (10)	0.0199 (4)
C7	0.2028 (2)	0.48181 (14)	0.44537 (10)	0.0199 (4)
C5	0.3582 (2)	0.44629 (14)	0.59152 (10)	0.0202 (4)
C15	0.3912 (2)	0.62469 (14)	0.66995 (10)	0.0206 (4)
C12	0.1396 (3)	0.77509 (15)	0.44053 (11)	0.0238 (4)
C1	0.5239 (3)	0.62799 (15)	0.79713 (11)	0.0270 (4)
C10	0.0304 (3)	0.71363 (16)	0.30895 (11)	0.0286 (4)
C3	0.4925 (2)	0.45453 (15)	0.73164 (10)	0.0223 (4)
C18	0.2975 (3)	0.09848 (17)	0.46821 (13)	0.0328 (5)
C8	0.1448 (2)	0.58082 (14)	0.40663 (10)	0.0204 (4)
C2	0.5502 (3)	0.51463 (15)	0.79815 (11)	0.0253 (4)
C9	0.0689 (2)	0.60677 (15)	0.32938 (11)	0.0231 (4)
C17	0.2236 (3)	0.18208 (15)	0.40799 (12)	0.0265 (4)
C11	0.0667 (3)	0.79580 (15)	0.36591 (11)	0.0266 (4)
H1	0.568 (3)	0.6713 (18)	0.8436 (12)	0.028 (5)*
H17A	0.302 (3)	0.1835 (16)	0.3619 (12)	0.023 (5)*
H2	0.607 (3)	0.4777 (17)	0.8449 (12)	0.026 (5)*
H9	0.043 (3)	0.5454 (19)	0.2945 (13)	0.033 (6)*
H3	0.513 (3)	0.3732 (18)	0.7311 (12)	0.031 (5)*
H12	0.167 (3)	0.8305 (18)	0.4819 (13)	0.032 (6)*
H10	−0.018 (3)	0.7362 (18)	0.2575 (13)	0.034 (6)*
H17B	0.079 (3)	0.1699 (18)	0.3898 (12)	0.033 (6)*
H18A	0.439 (4)	0.117 (2)	0.4875 (15)	0.052 (7)*
H18B	0.217 (4)	0.099 (2)	0.5139 (15)	0.045 (7)*
H18C	0.291 (3)	0.022 (2)	0.4457 (13)	0.039 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0529 (7)	0.0221 (6)	0.0372 (7)	0.0044 (5)	−0.0126 (5)	0.0072 (5)
O2	0.0321 (7)	0.0185 (6)	0.0281 (7)	0.0017 (5)	−0.0049 (5)	−0.0011 (5)
O3	0.0403 (7)	0.0246 (7)	0.0237 (7)	−0.0013 (6)	−0.0091 (6)	−0.0024 (5)
O1	0.0468 (8)	0.0173 (7)	0.0265 (7)	0.0026 (6)	−0.0071 (6)	0.0008 (5)
N1	0.0267 (8)	0.0217 (8)	0.0235 (8)	0.0003 (6)	−0.0008 (6)	−0.0025 (6)
O4	0.0408 (8)	0.0168 (6)	0.0278 (7)	0.0042 (6)	−0.0096 (6)	−0.0034 (5)
C4	0.0181 (8)	0.0186 (8)	0.0229 (9)	−0.0005 (6)	0.0003 (6)	−0.0009 (7)
N2	0.0178 (7)	0.0175 (7)	0.0229 (7)	0.0000 (5)	−0.0005 (5)	0.0003 (6)
C13	0.0175 (8)	0.0178 (8)	0.0218 (9)	0.0005 (6)	−0.0015 (6)	0.0025 (6)
C6	0.0169 (8)	0.0202 (8)	0.0208 (8)	0.0004 (6)	0.0009 (6)	−0.0008 (7)
C16	0.0165 (8)	0.0220 (9)	0.0227 (9)	−0.0015 (6)	0.0012 (6)	−0.0008 (7)
C14	0.0183 (8)	0.0160 (8)	0.0252 (9)	−0.0001 (6)	0.0010 (7)	−0.0008 (7)
C7	0.0173 (8)	0.0196 (8)	0.0223 (8)	−0.0005 (6)	−0.0016 (6)	−0.0004 (7)
C5	0.0201 (8)	0.0179 (9)	0.0225 (9)	−0.0007 (7)	0.0012 (7)	0.0019 (7)
C15	0.0212 (8)	0.0181 (8)	0.0219 (9)	−0.0023 (7)	−0.0010 (7)	−0.0002 (7)
C12	0.0235 (9)	0.0192 (9)	0.0284 (9)	0.0015 (7)	−0.0011 (7)	0.0025 (7)
C1	0.0330 (10)	0.0241 (9)	0.0231 (9)	−0.0005 (8)	−0.0046 (8)	−0.0025 (7)
C10	0.0277 (9)	0.0320 (10)	0.0251 (9)	0.0004 (8)	−0.0049 (7)	0.0037 (8)
C3	0.0230 (8)	0.0194 (9)	0.0243 (9)	−0.0006 (7)	0.0003 (7)	0.0020 (7)
C18	0.0386 (11)	0.0218 (10)	0.0375 (12)	0.0030 (8)	−0.0018 (9)	0.0016 (8)
C8	0.0174 (8)	0.0199 (9)	0.0237 (9)	−0.0011 (6)	−0.0001 (7)	−0.0002 (7)
C2	0.0297 (9)	0.0226 (9)	0.0229 (9)	0.0005 (7)	−0.0027 (7)	0.0028 (7)
C9	0.0219 (8)	0.0235 (9)	0.0234 (9)	−0.0002 (7)	−0.0023 (7)	0.0005 (7)
C17	0.0309 (10)	0.0186 (9)	0.0293 (10)	0.0002 (7)	−0.0023 (8)	−0.0053 (7)
C11	0.0286 (9)	0.0183 (9)	0.0320 (10)	0.0021 (7)	−0.0029 (8)	0.0069 (7)

Geometric parameters (Å, º) top

F1—C11	1.352 (2)	C7—C8	1.413 (2)
O2—C14	1.232 (2)	C12—C11	1.354 (3)
O3—C16	1.213 (2)	C12—H12	0.98 (2)
O1—C5	1.219 (2)	C1—C2	1.387 (3)
N1—C15	1.343 (2)	C1—H1	0.98 (2)
N1—C1	1.339 (2)	C10—C9	1.363 (3)
O4—C16	1.329 (2)	C10—C11	1.400 (3)
O4—C17	1.453 (2)	C10—H10	0.95 (2)
C4—C5	1.498 (2)	C3—C2	1.380 (3)
C4—C15	1.397 (2)	C3—H3	1.00 (2)
C4—C3	1.398 (2)	C18—C17	1.503 (3)
N2—C13	1.387 (2)	C18—H18A	1.02 (3)
N2—C12	1.377 (2)	C18—H18B	0.99 (3)
N2—C8	1.388 (2)	C18—H18C	1.00 (2)
C13—C6	1.392 (2)	C8—C9	1.414 (2)
C13—C14	1.443 (2)	C2—H2	0.97 (2)
C6—C7	1.420 (2)	C9—H9	0.96 (2)
C6—C5	1.484 (2)	C17—H17A	0.98 (2)
C16—C7	1.474 (2)	C17—H17B	1.02 (2)
C14—C15	1.501 (2)

C1—N1—C15	116.99 (15)	N1—C1—H1	117.0 (12)
C16—O4—C17	116.44 (13)	C2—C1—H1	119.3 (12)
C15—C4—C5	122.98 (15)	C9—C10—C11	118.60 (17)
C15—C4—C3	118.01 (16)	C9—C10—H10	123.7 (14)
C3—C4—C5	118.99 (15)	C11—C10—H10	117.7 (13)
C13—N2—C8	109.17 (14)	C4—C3—H3	121.3 (12)
C12—N2—C13	128.08 (15)	C2—C3—C4	118.75 (16)
C12—N2—C8	122.75 (15)	C2—C3—H3	119.9 (12)
N2—C13—C6	108.13 (14)	C17—C18—H18A	109.7 (15)
N2—C13—C14	124.58 (15)	C17—C18—H18B	110.7 (14)
C6—C13—C14	127.29 (15)	C17—C18—H18C	111.0 (13)
C13—C6—C7	108.00 (15)	H18A—C18—H18B	109 (2)
C13—C6—C5	118.44 (15)	H18A—C18—H18C	109.6 (19)
C7—C6—C5	133.55 (16)	H18B—C18—H18C	107.2 (19)
O3—C16—O4	123.11 (16)	N2—C8—C7	107.77 (14)
O3—C16—C7	122.68 (16)	N2—C8—C9	118.18 (15)
O4—C16—C7	114.21 (14)	C7—C8—C9	134.04 (16)
O2—C14—C13	123.79 (16)	C1—C2—H2	120.8 (12)
O2—C14—C15	121.81 (15)	C3—C2—C1	118.96 (17)
C13—C14—C15	114.40 (14)	C3—C2—H2	120.2 (12)
C6—C7—C16	132.87 (15)	C10—C9—C8	120.02 (17)
C8—C7—C6	106.93 (14)	C10—C9—H9	123.8 (13)
C8—C7—C16	120.18 (15)	C8—C9—H9	116.1 (13)
O1—C5—C4	119.70 (15)	O4—C17—C18	106.34 (15)
O1—C5—C6	124.04 (16)	O4—C17—H17A	107.5 (12)
C6—C5—C4	116.21 (14)	O4—C17—H17B	108.8 (12)
N1—C15—C4	123.62 (16)	C18—C17—H17A	112.4 (11)
N1—C15—C14	115.71 (15)	C18—C17—H17B	112.2 (12)
C4—C15—C14	120.65 (15)	H17A—C17—H17B	109.3 (16)
N2—C12—H12	117.3 (13)	F1—C11—C12	117.46 (17)
C11—C12—N2	116.90 (17)	F1—C11—C10	118.99 (16)
C11—C12—H12	125.8 (13)	C12—C11—C10	123.55 (17)
N1—C1—C2	123.66 (17)

O2—C14—C15—N1	−2.0 (2)	C14—C13—C6—C5	−1.6 (3)
O2—C14—C15—C4	179.59 (17)	C7—C6—C5—O1	3.6 (3)
O3—C16—C7—C6	175.43 (17)	C7—C6—C5—C4	−179.07 (17)
O3—C16—C7—C8	−2.5 (3)	C7—C8—C9—C10	−178.48 (19)
N1—C1—C2—C3	−0.5 (3)	C5—C4—C15—N1	−177.38 (16)
O4—C16—C7—C6	−4.0 (3)	C5—C4—C15—C14	0.9 (3)
O4—C16—C7—C8	178.07 (15)	C5—C4—C3—C2	177.18 (16)
C4—C3—C2—C1	1.0 (3)	C5—C6—C7—C16	3.4 (3)
N2—C13—C6—C7	−0.53 (19)	C5—C6—C7—C8	−178.46 (17)
N2—C13—C6—C5	178.65 (14)	C15—N1—C1—C2	0.2 (3)
N2—C13—C14—O2	0.6 (3)	C15—C4—C5—O1	175.68 (17)
N2—C13—C14—C15	−179.64 (15)	C15—C4—C5—C6	−1.8 (2)
N2—C12—C11—F1	−179.88 (16)	C15—C4—C3—C2	−1.3 (2)
N2—C12—C11—C10	0.0 (3)	C12—N2—C13—C6	−178.91 (16)
N2—C8—C9—C10	−0.2 (3)	C12—N2—C13—C14	1.3 (3)
C13—N2—C12—C11	178.63 (17)	C12—N2—C8—C7	179.30 (15)
C13—N2—C8—C7	0.03 (18)	C12—N2—C8—C9	0.6 (2)
C13—N2—C8—C9	−178.66 (15)	C1—N1—C15—C4	−0.4 (3)
C13—C6—C7—C16	−177.61 (17)	C1—N1—C15—C14	−178.78 (16)
C13—C6—C7—C8	0.54 (19)	C3—C4—C5—O1	−2.7 (2)
C13—C6—C5—O1	−175.32 (17)	C3—C4—C5—C6	179.87 (15)
C13—C6—C5—C4	2.0 (2)	C3—C4—C15—N1	1.0 (3)
C13—C14—C15—N1	178.18 (15)	C3—C4—C15—C14	179.27 (15)
C13—C14—C15—C4	−0.2 (2)	C8—N2—C13—C6	0.31 (19)
C6—C13—C14—O2	−179.20 (17)	C8—N2—C13—C14	−179.48 (16)
C6—C13—C14—C15	0.6 (3)	C8—N2—C12—C11	−0.5 (3)
C6—C7—C8—N2	−0.35 (18)	C9—C10—C11—F1	−179.75 (17)
C6—C7—C8—C9	178.04 (18)	C9—C10—C11—C12	0.4 (3)
C16—O4—C17—C18	−177.06 (16)	C17—O4—C16—O3	0.8 (3)
C16—C7—C8—N2	178.08 (15)	C17—O4—C16—C7	−179.83 (15)
C16—C7—C8—C9	−3.5 (3)	C11—C10—C9—C8	−0.2 (3)
C14—C13—C6—C7	179.26 (16)

Experimental details

Crystal data
Chemical formula	C₁₈H₁₁FN₂O₄
M_r	338.29
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	136
a, b, c (Å)	6.85562 (10), 12.12898 (16), 17.0304 (2)
β (°)	94.2306 (13)
V (Å³)	1412.25 (3)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	1.04
Crystal size (mm)	0.30 × 0.20 × 0.20

Data collection
Diffractometer	Agilent Xcalibur Onyx Nova
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2011)
T_min, T_max	0.550, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	5740, 2723, 2278
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.620

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.101, 1.08
No. of reflections	2723
No. of parameters	270
H-atom treatment	All H-atom parameters refined
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.24

Computer programs: CrysAlis PRO (Agilent, 2011), CrysAlis RED (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009), publCIF (Westrip, 2010).

Acknowledgements

The authors gratefully acknowledge financial support from the National Natural Science Foundation of China (No. 30801425) and the Guangdong Natural Science Fund (No. 10151008901000022).

References

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