organic compounds
Ethyl 2-(4-hydroxy-1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)acetate
aNational University of Pharmacy, 4 Blyukhera ave., Kharkiv 61002, Ukraine, and bSTC "Institute for Single Crystals", National Academy of Sciences of Ukraine, 60 Lenina ave., Kharkiv 61001, Ukraine
*Correspondence e-mail: uiv@kharkov.ua
In the title compound, C14H15NO4, the bicyclic fragment and the ester group form a dihedral angle of 86.7 (2)°. Intermolecular O—H⋯O and C—H⋯O hydrogen bonding connects molecules into a helix along the crystallographic b axis.
Related literature
For et al. (2001). For their use in the synthesis of natural see: Ramesh & Shanmugam (1985); Geismann & Cho (1959) and in highly active antithyroid substances, see: Ukrainets et al. (1997). For van der Waals radii, see: Zefirov (1997). For related structures, see: Jurd et al. (1983); Ukrainets et al. (2000). For bond-length data, see: Bürgi & Dunitz (1994).
of 4-hydroxy-2-oxo-1,2-dihydroquinolin-3-acetic acids as non-steroidal anti-inflammatory drugs, see: UkrainetsExperimental
Crystal data
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Data collection
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: XP (Siemens, 1998); software used to prepare material for publication: SHELXTL.
Supporting information
10.1107/S1600536809011921/kp2212sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809011921/kp2212Isup2.hkl
(4-Hydroxy-1-methyl-2-oxo-1,2-dihydroquinolin-3-yl)-acetic acid is synthesized from the methyl N-methyl anthranilate using the known method (Geismann & Cho, 1959) and then is esterified by ethanol (Ukrainets et al., 2001). Yield 96%. M.p. 454–457 K.
All hydrogen atoms were located from electron density difference maps and were refined isotropically.
Data collection: CrysAlis CCD (Oxford Diffraction, 2005); cell
CrysAlis RED (Oxford Diffraction, 2005); data reduction: CrysAlis RED (Oxford Diffraction, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: XP (Siemens, 1998); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).C14H15NO4 | Dx = 1.366 Mg m−3 |
Mr = 261.27 | Melting point: 455 K |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 21.608 (2) Å | Cell parameters from 8736 reflections |
b = 9.2155 (9) Å | θ = 4–32° |
c = 14.6795 (12) Å | µ = 0.10 mm−1 |
β = 119.632 (9)° | T = 293 K |
V = 2540.8 (4) Å3 | Block, colourless |
Z = 8 | 0.30 × 0.30 × 0.20 mm |
F(000) = 1104 |
Oxford Diffraction Xcalibur3 diffractometer | 2376 reflections with I > 2σ(I) |
Radiation source: Enhance (Mo) X-ray Source | Rint = 0.030 |
Graphite monochromator | θmax = 27.5°, θmin = 3.2° |
Detector resolution: 16.1827 pixels mm-1 | h = −28→28 |
ω scans | k = −11→11 |
13114 measured reflections | l = −19→19 |
2862 independent reflections |
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)] = 0.060 | Hydrogen site location: difference Fourier map |
wR(F2) = 0.171 | All H-atom parameters refined |
S = 1.19 | w = 1/[σ2(Fo2) + (0.0943P)2] where P = (Fo2 + 2Fc2)/3 |
2862 reflections | (Δ/σ)max < 0.001 |
232 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.19 e Å−3 |
C14H15NO4 | V = 2540.8 (4) Å3 |
Mr = 261.27 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 21.608 (2) Å | µ = 0.10 mm−1 |
b = 9.2155 (9) Å | T = 293 K |
c = 14.6795 (12) Å | 0.30 × 0.30 × 0.20 mm |
β = 119.632 (9)° |
Oxford Diffraction Xcalibur3 diffractometer | 2376 reflections with I > 2σ(I) |
13114 measured reflections | Rint = 0.030 |
2862 independent reflections |
R[F2 > 2σ(F2)] = 0.060 | 0 restraints |
wR(F2) = 0.171 | All H-atom parameters refined |
S = 1.19 | Δρmax = 0.28 e Å−3 |
2862 reflections | Δρmin = −0.19 e Å−3 |
232 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 | ||
N1 | 0.12615 (8) | 0.48562 (16) | 0.00279 (10) | 0.0447 (4) | |
O1 | 0.23317 (6) | 0.38519 (13) | 0.11389 (9) | 0.0511 (4) | |
O2 | 0.14804 (7) | 0.78108 (14) | 0.22763 (10) | 0.0528 (4) | |
H2O | 0.1932 (14) | 0.807 (3) | 0.284 (2) | 0.086 (8)* | |
O3 | 0.21567 (7) | 0.39416 (16) | 0.34316 (11) | 0.0651 (4) | |
O4 | 0.32312 (6) | 0.48690 (14) | 0.45168 (9) | 0.0525 (4) | |
C1 | 0.07158 (8) | 0.58298 (18) | −0.01697 (12) | 0.0434 (4) | |
C2 | 0.00694 (10) | 0.5816 (2) | −0.11336 (15) | 0.0566 (5) | |
H2 | 0.0020 (13) | 0.511 (3) | −0.161 (2) | 0.077 (7)* | |
C3 | −0.04624 (10) | 0.6786 (3) | −0.13061 (17) | 0.0652 (6) | |
H3 | −0.0931 (15) | 0.677 (3) | −0.195 (2) | 0.102 (9)* | |
C4 | −0.03752 (10) | 0.7799 (3) | −0.05606 (18) | 0.0638 (6) | |
H4 | −0.0737 (14) | 0.850 (3) | −0.064 (2) | 0.087 (7)* | |
C5 | 0.02492 (9) | 0.7826 (2) | 0.03876 (16) | 0.0541 (5) | |
H5 | 0.0334 (10) | 0.852 (2) | 0.0948 (15) | 0.054 (5)* | |
C6 | 0.07974 (8) | 0.68292 (17) | 0.05940 (13) | 0.0419 (4) | |
C7 | 0.14509 (8) | 0.68166 (17) | 0.15888 (12) | 0.0393 (4) | |
C8 | 0.19716 (8) | 0.58370 (17) | 0.17776 (12) | 0.0390 (4) | |
C9 | 0.18749 (9) | 0.47940 (18) | 0.09900 (12) | 0.0407 (4) | |
C10 | 0.26583 (8) | 0.57643 (19) | 0.28059 (12) | 0.0413 (4) | |
H10B | 0.3055 (9) | 0.5445 (19) | 0.2663 (13) | 0.042 (4)* | |
H10A | 0.2774 (9) | 0.668 (2) | 0.3117 (14) | 0.044 (5)* | |
C11 | 0.26352 (8) | 0.47532 (18) | 0.35929 (13) | 0.0416 (4) | |
C12 | 0.32854 (11) | 0.3976 (2) | 0.53692 (15) | 0.0564 (5) | |
H12B | 0.2882 (13) | 0.416 (3) | 0.5450 (19) | 0.082 (7)* | |
H12A | 0.3291 (12) | 0.291 (3) | 0.5182 (18) | 0.084 (7)* | |
C13 | 0.39738 (15) | 0.4393 (3) | 0.63283 (17) | 0.0757 (7) | |
H13C | 0.3974 (17) | 0.546 (4) | 0.658 (2) | 0.132 (12)* | |
H13B | 0.4378 (17) | 0.416 (4) | 0.623 (3) | 0.119 (11)* | |
H13A | 0.4017 (15) | 0.380 (3) | 0.688 (2) | 0.105 (9)* | |
C14 | 0.11943 (14) | 0.3847 (3) | −0.07860 (17) | 0.0627 (5) | |
H14C | 0.1113 (13) | 0.444 (3) | −0.1404 (19) | 0.084 (7)* | |
H14B | 0.1627 (16) | 0.332 (3) | −0.050 (2) | 0.105 (10)* | |
H14A | 0.0770 (14) | 0.324 (3) | −0.0999 (19) | 0.080 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0472 (8) | 0.0479 (8) | 0.0323 (7) | −0.0083 (6) | 0.0145 (6) | 0.0011 (6) |
O1 | 0.0542 (7) | 0.0477 (7) | 0.0450 (7) | 0.0045 (5) | 0.0196 (6) | 0.0028 (5) |
O2 | 0.0436 (7) | 0.0519 (7) | 0.0528 (7) | −0.0003 (5) | 0.0160 (6) | −0.0072 (6) |
O3 | 0.0505 (8) | 0.0751 (10) | 0.0550 (8) | −0.0127 (6) | 0.0149 (6) | 0.0126 (7) |
O4 | 0.0458 (7) | 0.0627 (8) | 0.0352 (6) | 0.0027 (5) | 0.0095 (5) | 0.0072 (5) |
C1 | 0.0368 (8) | 0.0472 (9) | 0.0359 (8) | −0.0093 (7) | 0.0101 (7) | 0.0112 (7) |
C2 | 0.0476 (10) | 0.0667 (13) | 0.0378 (9) | −0.0157 (9) | 0.0075 (8) | 0.0124 (9) |
C3 | 0.0387 (10) | 0.0794 (15) | 0.0531 (11) | −0.0089 (9) | 0.0040 (8) | 0.0275 (11) |
C4 | 0.0373 (10) | 0.0654 (13) | 0.0707 (13) | 0.0015 (9) | 0.0129 (9) | 0.0215 (11) |
C5 | 0.0400 (9) | 0.0511 (11) | 0.0597 (11) | −0.0004 (8) | 0.0159 (8) | 0.0127 (9) |
C6 | 0.0345 (8) | 0.0410 (9) | 0.0417 (8) | −0.0051 (6) | 0.0123 (7) | 0.0121 (7) |
C7 | 0.0356 (8) | 0.0383 (8) | 0.0380 (8) | −0.0068 (6) | 0.0137 (6) | 0.0032 (6) |
C8 | 0.0356 (8) | 0.0384 (8) | 0.0337 (8) | −0.0037 (6) | 0.0100 (6) | 0.0046 (6) |
C9 | 0.0420 (9) | 0.0398 (8) | 0.0356 (8) | −0.0045 (6) | 0.0156 (7) | 0.0050 (6) |
C10 | 0.0340 (8) | 0.0394 (9) | 0.0380 (9) | −0.0014 (6) | 0.0084 (7) | −0.0008 (6) |
C11 | 0.0365 (8) | 0.0442 (9) | 0.0372 (8) | 0.0059 (6) | 0.0128 (7) | −0.0017 (6) |
C12 | 0.0600 (12) | 0.0693 (14) | 0.0412 (10) | 0.0198 (9) | 0.0259 (9) | 0.0129 (9) |
C13 | 0.0800 (17) | 0.0909 (19) | 0.0360 (10) | 0.0189 (14) | 0.0134 (10) | 0.0088 (11) |
C14 | 0.0691 (14) | 0.0706 (14) | 0.0398 (10) | −0.0091 (11) | 0.0204 (10) | −0.0092 (10) |
N1—C9 | 1.380 (2) | C5—H5 | 0.98 (2) |
N1—C1 | 1.393 (2) | C6—C7 | 1.445 (2) |
N1—C14 | 1.463 (3) | C7—C8 | 1.360 (2) |
O1—C9 | 1.250 (2) | C8—C9 | 1.437 (2) |
O2—C7 | 1.341 (2) | C8—C10 | 1.507 (2) |
O2—H2O | 0.95 (3) | C10—C11 | 1.504 (2) |
O3—C11 | 1.201 (2) | C10—H10B | 1.021 (18) |
O4—C11 | 1.335 (2) | C10—H10A | 0.935 (19) |
O4—C12 | 1.453 (2) | C12—C13 | 1.507 (3) |
C1—C6 | 1.393 (2) | C12—H12B | 0.95 (2) |
C1—C2 | 1.414 (2) | C12—H12A | 1.02 (3) |
C2—C3 | 1.377 (3) | C13—H13C | 1.05 (4) |
C2—H2 | 0.92 (3) | C13—H13B | 0.98 (3) |
C3—C4 | 1.378 (3) | C13—H13A | 0.94 (3) |
C3—H3 | 0.99 (3) | C14—H14C | 1.00 (3) |
C4—C5 | 1.379 (3) | C14—H14B | 0.95 (3) |
C4—H4 | 0.97 (3) | C14—H14A | 0.98 (3) |
C5—C6 | 1.409 (2) | ||
C9—N1—C1 | 121.71 (14) | O1—C9—C8 | 122.39 (14) |
C9—N1—C14 | 117.82 (16) | N1—C9—C8 | 118.67 (14) |
C1—N1—C14 | 120.46 (16) | C11—C10—C8 | 114.00 (13) |
C7—O2—H2O | 118.5 (15) | C11—C10—H10B | 109.2 (10) |
C11—O4—C12 | 117.13 (15) | C8—C10—H10B | 108.6 (10) |
C6—C1—N1 | 120.06 (14) | C11—C10—H10A | 106.7 (11) |
C6—C1—C2 | 118.72 (17) | C8—C10—H10A | 110.0 (10) |
N1—C1—C2 | 121.21 (17) | H10B—C10—H10A | 108.2 (14) |
C3—C2—C1 | 120.0 (2) | O3—C11—O4 | 123.65 (16) |
C3—C2—H2 | 123.1 (16) | O3—C11—C10 | 125.92 (15) |
C1—C2—H2 | 116.8 (16) | O4—C11—C10 | 110.43 (14) |
C2—C3—C4 | 121.30 (18) | O4—C12—C13 | 106.40 (19) |
C2—C3—H3 | 122.3 (17) | O4—C12—H12B | 108.5 (15) |
C4—C3—H3 | 116.4 (16) | C13—C12—H12B | 112.4 (14) |
C3—C4—C5 | 119.7 (2) | O4—C12—H12A | 108.7 (14) |
C3—C4—H4 | 124.4 (15) | C13—C12—H12A | 111.0 (13) |
C5—C4—H4 | 115.9 (16) | H12B—C12—H12A | 110 (2) |
C4—C5—C6 | 120.3 (2) | C12—C13—H13C | 113.3 (18) |
C4—C5—H5 | 122.7 (11) | C12—C13—H13B | 110 (2) |
C6—C5—H5 | 117.1 (11) | H13C—C13—H13B | 114 (3) |
C1—C6—C5 | 119.99 (15) | C12—C13—H13A | 106.8 (18) |
C1—C6—C7 | 118.66 (14) | H13C—C13—H13A | 105 (3) |
C5—C6—C7 | 121.36 (17) | H13B—C13—H13A | 107 (3) |
O2—C7—C8 | 124.99 (14) | N1—C14—H14C | 107.4 (15) |
O2—C7—C6 | 114.46 (14) | N1—C14—H14B | 106.9 (18) |
C8—C7—C6 | 120.53 (15) | H14C—C14—H14B | 112 (2) |
C7—C8—C9 | 120.23 (14) | N1—C14—H14A | 108.7 (15) |
C7—C8—C10 | 122.64 (15) | H14C—C14—H14A | 107.6 (19) |
C9—C8—C10 | 117.11 (14) | H14B—C14—H14A | 114 (2) |
O1—C9—N1 | 118.92 (15) | ||
C9—N1—C1—C6 | 3.6 (2) | O2—C7—C8—C9 | 178.40 (14) |
C14—N1—C1—C6 | −177.17 (16) | C6—C7—C8—C9 | −0.4 (2) |
C9—N1—C1—C2 | −175.56 (14) | O2—C7—C8—C10 | −0.3 (2) |
C14—N1—C1—C2 | 3.7 (2) | C6—C7—C8—C10 | −179.14 (14) |
C6—C1—C2—C3 | 0.5 (2) | C1—N1—C9—O1 | 176.58 (14) |
N1—C1—C2—C3 | 179.68 (15) | C14—N1—C9—O1 | −2.7 (2) |
C1—C2—C3—C4 | 1.1 (3) | C1—N1—C9—C8 | −4.7 (2) |
C2—C3—C4—C5 | −1.5 (3) | C14—N1—C9—C8 | 176.02 (16) |
C3—C4—C5—C6 | 0.2 (3) | C7—C8—C9—O1 | −178.23 (15) |
N1—C1—C6—C5 | 179.10 (14) | C10—C8—C9—O1 | 0.5 (2) |
C2—C1—C6—C5 | −1.7 (2) | C7—C8—C9—N1 | 3.1 (2) |
N1—C1—C6—C7 | −0.8 (2) | C10—C8—C9—N1 | −178.10 (13) |
C2—C1—C6—C7 | 178.41 (14) | C7—C8—C10—C11 | 90.75 (19) |
C4—C5—C6—C1 | 1.4 (3) | C9—C8—C10—C11 | −87.98 (19) |
C4—C5—C6—C7 | −178.75 (16) | C12—O4—C11—O3 | −1.4 (2) |
C1—C6—C7—O2 | −179.69 (13) | C12—O4—C11—C10 | 178.93 (15) |
C5—C6—C7—O2 | 0.4 (2) | C8—C10—C11—O3 | 7.3 (3) |
C1—C6—C7—C8 | −0.7 (2) | C8—C10—C11—O4 | −173.09 (13) |
C5—C6—C7—C8 | 179.38 (15) | C11—O4—C12—C13 | −175.83 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···O1i | 0.95 (3) | 1.71 (3) | 2.649 (2) | 169 (2) |
C10—H10a···O1i | 0.94 (2) | 2.34 (3) | 3.235 (2) | 159 (2) |
Symmetry code: (i) −x+1/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H15NO4 |
Mr | 261.27 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 293 |
a, b, c (Å) | 21.608 (2), 9.2155 (9), 14.6795 (12) |
β (°) | 119.632 (9) |
V (Å3) | 2540.8 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.30 × 0.30 × 0.20 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur3 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 13114, 2862, 2376 |
Rint | 0.030 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.060, 0.171, 1.19 |
No. of reflections | 2862 |
No. of parameters | 232 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.28, −0.19 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2005), CrysAlis RED (Oxford Diffraction, 2005), SHELXTL (Sheldrick, 2008), XP (Siemens, 1998).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···O1i | 0.95 (3) | 1.71 (3) | 2.649 (2) | 169 (2) |
C10—H10a···O1i | 0.94 (2) | 2.34 (3) | 3.235 (2) | 159 (2) |
Symmetry code: (i) −x+1/2, y+1/2, −z+1/2. |
References
Bürgi, H.-B. & Dunitz, J. D. (1994). Structure Correlation, Vol. 2, pp. 767-784. Weinheim: VCH. Google Scholar
Geismann, T. A. & Cho, A. K. (1959). J. Org. Chem. 24, 41–43. Google Scholar
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Oxford Diffraction (2005). CrysAlis CCD and CrysAlis RED. Oxford Diffraction, Abingdon, England. Google Scholar
Ramesh, M. & Shanmugam, P. (1985). Indian J. Chem. Sect. B, 24, 602–604. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Esters of 4-hydroxy-2-oxo-1,2-dihydroquinolin-3-acetic acids can be considered as non-steroid anti-inflammatory drugs (Ukrainets et al., 2001). However they are of great interest for synthesis of natural alkaloids (Ramesh & Shanmugam, 1985; Geismann & Cho, 1959) and highly active antithyroid substances (Ukrainets et al., 1997). In the present paper, we report the crystal structure of the (4-hydroxy-1-methyl-2-oxo-1,2-dihydro- quinolin-3-yl)-acetic acid ethyl ester (I) (Fig. 1). The bicyclic fragment and the C14, O1, C10 and O2 atoms are coplanar within 0.02 Å. The planar ester group at the C10 atom has orthogonal orientation with respect to the plane of quinolone bicycle (the C7—C8—C10—C11 torsion angle is 90.8 (2) %A) whereas the C8—C10—C11—O3 torsion angle is 7.3 (3) %A). The C9—O1 bond (1.250 (2) Å) is elongated as compared with its mean value (1.210 Å; Bürgi & Dunitz, 1994) owing to the formation of the intermolecular hydrogen bond O2—H2O···O1' (Table 1). The presence of hydrogen bond affects the orientation of the hydrogen atom of hydroxy group despite of strong repulsion with hydrogen atom of neighbouring methylene group: distance H10a···H2O is 2.09 Å [the van der Waals radii sum is 2.34 Å (Zefirov, 1997)]. It should be noted that the C7—O2 bond length (1.341 (2) Å) is close to its mean value 1.333 Å observed in earlier investigated compounds (Jurd et al., 1983; Ukrainets et al., 2000). In the crystal the molecules form the infinite helix along the [0 1 0] direction (Fig. 2) via the O2—H2O···O1 intermolecular hydrogen bond between hydroxyl group of one molecule and carbonyl group of quinolone fragment of neighbouring molecule. The C10—H10a···O1' intermolecular hydrogen bond (Table 1) occurs as well.