organic compounds
Ethyl 8-chloro-1-cyclopropyl-6,7-difluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate
aDepartment of Applied Chemistry, Nanjing College of Chemical Technology, Geguan Road No. 265 Nanjing, Nanjing 210048, People's Republic of China, bR&D Center, Jiangsu Yabang Pharmaceutical Group, Liangchang Road East No. 6 Jingtan, Changzhou 213200, People's Republic of China, and cDepartment of Chemical Engineering, Nanjing College of Chemical Technology, Geguan Road No. 265 Nanjing, Nanjing 210048, People's Republic of China
*Correspondence e-mail: njutshs@126.com
In the molecule of the title compound, C15H12ClF2NO3, the quinoline ring system is not planar, the dihedral angle between the pyridine and benzene rings being 3.55 (8)°. In the crystal, intermolecular C—H⋯O hydrogen bonds link the molecules into layers parallel to (101).
Related literature
For the antibacterial activity of quinolone derivatives, see: Fujita & Chiba (1998). For a related structure, see: Wang et al. (2008).
Experimental
Crystal data
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Refinement
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Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S160053681104205X/rz2646sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681104205X/rz2646Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681104205X/rz2646Isup3.cml
A solution of 3-cyclopropylamino-2-(2,4,5-trifluoro-3-chlorobenzoyl)acrylic acid ethyl ester (26.1 g, 0.075 mol) in DMF (110 ml) was treated with K2CO3 (22 g, 0.16 mol) and then heated to 50°C with stirring for 1 h. The resulting precipitate was filtered, washed with a mixture of ice and water, and dried to give 22 g of the title compound (yield 90%). Crystals of the title compound suitable for X-ray
were obtained by slow evaporation of an acetone solution.All H atoms were positioned geometrically and refined using a riding model with C—H = 0.93–0.98 Å and Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating-group model was applied for the methyl groups.
Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell
CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo,1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level. |
C15H12ClF2NO3 | F(000) = 672 |
Mr = 327.71 | Dx = 1.541 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 25 reflections |
a = 11.336 (2) Å | θ = 9–13° |
b = 7.7440 (15) Å | µ = 0.31 mm−1 |
c = 16.157 (3) Å | T = 293 K |
β = 95.40 (3)° | Block, colourless |
V = 1412.1 (5) Å3 | 0.30 × 0.20 × 0.10 mm |
Z = 4 |
Enraf–Nonius CAD-4 diffractometer | 1728 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.025 |
Graphite monochromator | θmax = 25.4°, θmin = 2.1° |
ω/2θ scans | h = 0→13 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→9 |
Tmin = 0.914, Tmax = 0.970 | l = −19→19 |
2741 measured reflections | 3 standard reflections every 200 reflections |
2604 independent reflections | intensity decay: 1% |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.053 | H-atom parameters constrained |
wR(F2) = 0.158 | w = 1/[σ2(Fo2) + (0.094P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max < 0.001 |
2604 reflections | Δρmax = 0.21 e Å−3 |
200 parameters | Δρmin = −0.25 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.022 (3) |
C15H12ClF2NO3 | V = 1412.1 (5) Å3 |
Mr = 327.71 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 11.336 (2) Å | µ = 0.31 mm−1 |
b = 7.7440 (15) Å | T = 293 K |
c = 16.157 (3) Å | 0.30 × 0.20 × 0.10 mm |
β = 95.40 (3)° |
Enraf–Nonius CAD-4 diffractometer | 1728 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.025 |
Tmin = 0.914, Tmax = 0.970 | 3 standard reflections every 200 reflections |
2741 measured reflections | intensity decay: 1% |
2604 independent reflections |
R[F2 > 2σ(F2)] = 0.053 | 0 restraints |
wR(F2) = 0.158 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.21 e Å−3 |
2604 reflections | Δρmin = −0.25 e Å−3 |
200 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cl | 0.19669 (7) | 0.51225 (11) | 0.40024 (6) | 0.0668 (4) | |
N | 0.44922 (19) | 0.3170 (3) | 0.40949 (14) | 0.0419 (6) | |
O1 | 0.59434 (19) | 0.1055 (3) | 0.62827 (13) | 0.0642 (7) | |
C1 | 0.3696 (3) | 0.2253 (4) | 0.62119 (19) | 0.0544 (8) | |
H1A | 0.4037 | 0.1728 | 0.6694 | 0.065* | |
F1 | 0.19320 (19) | 0.2766 (4) | 0.68412 (14) | 0.0983 (8) | |
O2 | 0.79506 (19) | 0.0443 (3) | 0.54403 (15) | 0.0651 (7) | |
F2 | 0.09874 (16) | 0.4358 (3) | 0.54885 (14) | 0.0800 (7) | |
C2 | 0.2582 (3) | 0.2886 (5) | 0.6180 (2) | 0.0631 (9) | |
O3 | 0.79232 (18) | 0.1827 (3) | 0.42263 (14) | 0.0627 (6) | |
C3 | 0.2086 (3) | 0.3706 (4) | 0.5476 (2) | 0.0570 (9) | |
C4 | 0.2681 (3) | 0.3882 (4) | 0.47802 (19) | 0.0485 (8) | |
C5 | 0.3828 (2) | 0.3153 (3) | 0.47746 (17) | 0.0399 (7) | |
C6 | 0.4329 (2) | 0.2392 (4) | 0.55187 (17) | 0.0420 (7) | |
C7 | 0.5626 (2) | 0.2603 (4) | 0.41917 (17) | 0.0436 (7) | |
H7A | 0.6060 | 0.2690 | 0.3733 | 0.052* | |
C8 | 0.6190 (2) | 0.1915 (4) | 0.48987 (17) | 0.0421 (7) | |
C9 | 0.5555 (2) | 0.1703 (4) | 0.56176 (17) | 0.0440 (7) | |
C10 | 0.4003 (3) | 0.3598 (4) | 0.32426 (17) | 0.0499 (8) | |
H10A | 0.3941 | 0.4831 | 0.3109 | 0.060* | |
C11 | 0.3070 (3) | 0.2476 (4) | 0.28256 (18) | 0.0569 (9) | |
H11A | 0.2816 | 0.1486 | 0.3131 | 0.068* | |
H11B | 0.2450 | 0.3023 | 0.2462 | 0.068* | |
C12 | 0.4275 (3) | 0.2441 (5) | 0.25528 (18) | 0.0630 (9) | |
H12A | 0.4393 | 0.2967 | 0.2022 | 0.076* | |
H12B | 0.4759 | 0.1431 | 0.2692 | 0.076* | |
C13 | 0.7432 (3) | 0.1294 (4) | 0.49057 (19) | 0.0475 (7) | |
C14 | 0.9161 (3) | 0.1308 (6) | 0.4192 (2) | 0.0697 (10) | |
H14A | 0.9241 | 0.0067 | 0.4261 | 0.084* | |
H14B | 0.9663 | 0.1869 | 0.4632 | 0.084* | |
C15 | 0.9506 (4) | 0.1833 (6) | 0.3377 (2) | 0.0891 (13) | |
H15A | 1.0316 | 0.1516 | 0.3332 | 0.134* | |
H15B | 0.9421 | 0.3062 | 0.3317 | 0.134* | |
H15C | 0.9005 | 0.1266 | 0.2947 | 0.134* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl | 0.0592 (5) | 0.0603 (6) | 0.0764 (6) | 0.0187 (4) | −0.0166 (4) | −0.0001 (4) |
N | 0.0404 (13) | 0.0399 (13) | 0.0437 (13) | −0.0013 (10) | −0.0054 (10) | 0.0007 (10) |
O1 | 0.0579 (13) | 0.0809 (17) | 0.0511 (13) | 0.0097 (12) | −0.0089 (10) | 0.0147 (12) |
C1 | 0.056 (2) | 0.058 (2) | 0.0477 (17) | −0.0018 (16) | 0.0012 (15) | 0.0002 (15) |
F1 | 0.0732 (15) | 0.146 (2) | 0.0798 (14) | 0.0125 (15) | 0.0296 (12) | 0.0032 (15) |
O2 | 0.0507 (13) | 0.0699 (16) | 0.0727 (15) | 0.0149 (11) | −0.0035 (12) | 0.0137 (13) |
F2 | 0.0461 (11) | 0.0932 (16) | 0.1010 (16) | 0.0177 (11) | 0.0077 (11) | −0.0139 (13) |
C2 | 0.055 (2) | 0.078 (2) | 0.058 (2) | −0.0008 (18) | 0.0145 (17) | −0.0068 (18) |
O3 | 0.0421 (12) | 0.0806 (17) | 0.0646 (14) | 0.0079 (11) | 0.0012 (10) | 0.0107 (13) |
C3 | 0.0412 (17) | 0.060 (2) | 0.069 (2) | 0.0050 (15) | 0.0009 (16) | −0.0149 (18) |
C4 | 0.0454 (17) | 0.0388 (16) | 0.0585 (19) | 0.0015 (13) | −0.0102 (15) | −0.0070 (14) |
C5 | 0.0364 (14) | 0.0321 (14) | 0.0493 (16) | −0.0045 (12) | −0.0057 (12) | −0.0023 (12) |
C6 | 0.0423 (16) | 0.0381 (15) | 0.0440 (15) | −0.0032 (12) | −0.0039 (13) | −0.0028 (13) |
C7 | 0.0408 (16) | 0.0427 (16) | 0.0470 (16) | −0.0042 (13) | 0.0024 (13) | −0.0002 (14) |
C8 | 0.0396 (15) | 0.0378 (15) | 0.0471 (16) | −0.0035 (12) | −0.0043 (13) | −0.0024 (13) |
C9 | 0.0445 (16) | 0.0395 (16) | 0.0452 (17) | −0.0026 (13) | −0.0110 (13) | −0.0020 (14) |
C10 | 0.0549 (18) | 0.0459 (17) | 0.0460 (17) | 0.0000 (14) | −0.0102 (14) | 0.0065 (14) |
C11 | 0.055 (2) | 0.061 (2) | 0.0516 (17) | 0.0007 (16) | −0.0129 (15) | 0.0014 (16) |
C12 | 0.069 (2) | 0.076 (2) | 0.0430 (17) | 0.0012 (19) | 0.0009 (16) | 0.0032 (17) |
C13 | 0.0442 (16) | 0.0441 (17) | 0.0526 (18) | −0.0020 (14) | −0.0044 (14) | −0.0023 (15) |
C14 | 0.0433 (18) | 0.087 (3) | 0.079 (2) | 0.0094 (18) | 0.0044 (17) | 0.005 (2) |
C15 | 0.072 (3) | 0.106 (3) | 0.092 (3) | 0.008 (2) | 0.022 (2) | 0.004 (3) |
Cl—C4 | 1.723 (3) | C7—C8 | 1.364 (4) |
N—C7 | 1.353 (3) | C7—H7A | 0.9300 |
N—C5 | 1.389 (4) | C8—C9 | 1.432 (4) |
N—C10 | 1.473 (3) | C8—C13 | 1.486 (4) |
O1—C9 | 1.229 (3) | C10—C11 | 1.481 (4) |
C1—C2 | 1.351 (5) | C10—C12 | 1.485 (4) |
C1—C6 | 1.390 (4) | C10—H10A | 0.9800 |
C1—H1A | 0.9300 | C11—C12 | 1.475 (5) |
F1—C2 | 1.357 (4) | C11—H11A | 0.9700 |
O2—C13 | 1.196 (3) | C11—H11B | 0.9700 |
F2—C3 | 1.346 (4) | C12—H12A | 0.9700 |
C2—C3 | 1.375 (5) | C12—H12B | 0.9700 |
O3—C13 | 1.342 (4) | C14—C15 | 1.467 (5) |
O3—C14 | 1.466 (4) | C14—H14A | 0.9700 |
C3—C4 | 1.371 (4) | C14—H14B | 0.9700 |
C4—C5 | 1.418 (4) | C15—H15A | 0.9600 |
C5—C6 | 1.410 (4) | C15—H15B | 0.9600 |
C6—C9 | 1.483 (4) | C15—H15C | 0.9600 |
C7—N—C5 | 119.0 (2) | N—C10—C12 | 118.7 (3) |
C7—N—C10 | 116.8 (2) | C11—C10—C12 | 59.6 (2) |
C5—N—C10 | 123.8 (2) | N—C10—H10A | 116.0 |
C2—C1—C6 | 119.5 (3) | C11—C10—H10A | 116.0 |
C2—C1—H1A | 120.3 | C12—C10—H10A | 116.0 |
C6—C1—H1A | 120.3 | C12—C11—C10 | 60.3 (2) |
C1—C2—F1 | 121.3 (3) | C12—C11—H11A | 117.7 |
C1—C2—C3 | 120.5 (3) | C10—C11—H11A | 117.7 |
F1—C2—C3 | 118.2 (3) | C12—C11—H11B | 117.7 |
C13—O3—C14 | 114.8 (2) | C10—C11—H11B | 117.7 |
F2—C3—C4 | 120.2 (3) | H11A—C11—H11B | 114.9 |
F2—C3—C2 | 117.9 (3) | C11—C12—C10 | 60.1 (2) |
C4—C3—C2 | 121.9 (3) | C11—C12—H12A | 117.8 |
C3—C4—C5 | 119.2 (3) | C10—C12—H12A | 117.8 |
C3—C4—Cl | 114.8 (2) | C11—C12—H12B | 117.8 |
C5—C4—Cl | 125.9 (3) | C10—C12—H12B | 117.8 |
N—C5—C6 | 118.3 (2) | H12A—C12—H12B | 114.9 |
N—C5—C4 | 124.5 (3) | O2—C13—O3 | 123.1 (3) |
C6—C5—C4 | 117.2 (3) | O2—C13—C8 | 125.8 (3) |
C1—C6—C5 | 121.5 (3) | O3—C13—C8 | 111.1 (3) |
C1—C6—C9 | 115.8 (3) | O3—C14—C15 | 107.1 (3) |
C5—C6—C9 | 122.7 (3) | O3—C14—H14A | 110.3 |
N—C7—C8 | 126.1 (3) | C15—C14—H14A | 110.3 |
N—C7—H7A | 116.9 | O3—C14—H14B | 110.3 |
C8—C7—H7A | 116.9 | C15—C14—H14B | 110.3 |
C7—C8—C9 | 119.4 (3) | H14A—C14—H14B | 108.5 |
C7—C8—C13 | 120.1 (3) | C14—C15—H15A | 109.5 |
C9—C8—C13 | 120.3 (3) | C14—C15—H15B | 109.5 |
O1—C9—C8 | 126.1 (3) | H15A—C15—H15B | 109.5 |
O1—C9—C6 | 119.7 (3) | C14—C15—H15C | 109.5 |
C8—C9—C6 | 114.2 (2) | H15A—C15—H15C | 109.5 |
N—C10—C11 | 118.9 (3) | H15B—C15—H15C | 109.5 |
C6—C1—C2—F1 | 179.6 (3) | C10—N—C7—C8 | −170.2 (3) |
C6—C1—C2—C3 | −1.8 (5) | N—C7—C8—C9 | 1.7 (4) |
C1—C2—C3—F2 | −178.0 (3) | N—C7—C8—C13 | 178.1 (3) |
F1—C2—C3—F2 | 0.7 (5) | C7—C8—C9—O1 | 177.6 (3) |
C1—C2—C3—C4 | 1.4 (5) | C13—C8—C9—O1 | 1.3 (5) |
F1—C2—C3—C4 | −179.9 (3) | C7—C8—C9—C6 | −3.9 (4) |
F2—C3—C4—C5 | −178.7 (3) | C13—C8—C9—C6 | 179.8 (2) |
C2—C3—C4—C5 | 2.0 (5) | C1—C6—C9—O1 | 0.3 (4) |
F2—C3—C4—Cl | 5.2 (4) | C5—C6—C9—O1 | 179.9 (3) |
C2—C3—C4—Cl | −174.1 (3) | C1—C6—C9—C8 | −178.3 (2) |
C7—N—C5—C6 | −5.9 (4) | C5—C6—C9—C8 | 1.3 (4) |
C10—N—C5—C6 | 167.3 (2) | C7—N—C10—C11 | 110.6 (3) |
C7—N—C5—C4 | 172.8 (3) | C5—N—C10—C11 | −62.8 (4) |
C10—N—C5—C4 | −13.9 (4) | C7—N—C10—C12 | 41.4 (4) |
C3—C4—C5—N | 176.6 (3) | C5—N—C10—C12 | −132.0 (3) |
Cl—C4—C5—N | −7.8 (4) | N—C10—C11—C12 | −108.2 (3) |
C3—C4—C5—C6 | −4.7 (4) | N—C10—C12—C11 | 108.5 (3) |
Cl—C4—C5—C6 | 170.9 (2) | C14—O3—C13—O2 | −0.9 (5) |
C2—C1—C6—C5 | −1.1 (5) | C14—O3—C13—C8 | 178.5 (3) |
C2—C1—C6—C9 | 178.4 (3) | C7—C8—C13—O2 | −168.0 (3) |
N—C5—C6—C1 | −176.8 (3) | C9—C8—C13—O2 | 8.3 (5) |
C4—C5—C6—C1 | 4.3 (4) | C7—C8—C13—O3 | 12.5 (4) |
N—C5—C6—C9 | 3.6 (4) | C9—C8—C13—O3 | −171.2 (2) |
C4—C5—C6—C9 | −175.2 (3) | C13—O3—C14—C15 | 174.0 (3) |
C5—N—C7—C8 | 3.5 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O1i | 0.97 | 2.55 | 3.240 (4) | 128 |
C11—H11B···O1ii | 0.97 | 2.54 | 3.491 (4) | 167 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x−1/2, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H12ClF2NO3 |
Mr | 327.71 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 293 |
a, b, c (Å) | 11.336 (2), 7.7440 (15), 16.157 (3) |
β (°) | 95.40 (3) |
V (Å3) | 1412.1 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.31 |
Crystal size (mm) | 0.30 × 0.20 × 0.10 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.914, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2741, 2604, 1728 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.603 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.053, 0.158, 1.00 |
No. of reflections | 2604 |
No. of parameters | 200 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.25 |
Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo,1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11A···O1i | 0.9700 | 2.5500 | 3.240 (4) | 128.00 |
C11—H11B···O1ii | 0.9700 | 2.5400 | 3.491 (4) | 167.00 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x−1/2, −y+1/2, z−1/2. |
Acknowledgements
The authors thank the Center of Testing and Analysis, Nanjing University, for support.
References
Enraf–Nonius (1994). CAD-4 EXPRESS. Enraf–Nonius, Delft, The Netherlands. Google Scholar
Fujita, M. & Chiba, K. (1998). Chem. Pharm. Bull. 46, 631–638. Web of Science CrossRef CAS PubMed Google Scholar
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany. Google Scholar
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359. CrossRef IUCr Journals Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Wang, D.-C., Huang, X.-M., Liu, Y.-P. & Tang, C.-L. (2008). Acta Cryst. E64, o2214. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Quinolone antibacterials were found several decades ago, and some excellent antibacterials have been developed and used widely (Fujita & Chiba, 1998). An interest in the search of more potent antibacterial agents led us to design and synthesize a new type of quinoline derivative. The title compound is one of the key intermediates and we report here its crystal structure.
The quinoline ring system is not planar, the dihedral angle between the pyridine and benzene rings being 3.55 (8)°. The dihedral angle between the three-membered ring and the quinoline ring system is 80.5 (5)°. Bond lengths and angles agree well with those observed in the strictly related compound ethyl 1-cyclopropyl-6,7-difluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylate reported recently (Wang et al., 2008). In the crystal structure, intermolecular C—H···O hydrogen bonds link molecules into layers parallel to the (101) plane.