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Acta Crystallogr Sect E Struct Rep Online. 2009 November 1; 65(Pt 11): o2664.
Published online 2009 October 7. doi:  10.1107/S1600536809039877
PMCID: PMC2971334

Ethyl 4-(3-hydroxy­phen­yl)-2,7,7-trimethyl-5-oxo-1,4,5,6,7,8-hexa­hydro­quinoline-3-carboxyl­ate

Abstract

In the mol­ecular structure of the title compound, C21H25NO4, the dihydro­pyridine ring adopts a flattened boat conformation while the cyclo­hexenone ring is in an envelope conformation. In the crystal structure, mol­ecules are linked into a two-dimensional network parallel to (10An external file that holds a picture, illustration, etc.
Object name is e-65-o2664-efi1.jpg) by N—H(...)O and O—H(...)O hydrogen bonds. The network is generated by R 4 4(30) and R 4 4(34) graph-set motifs.

Related literature

For general background to oxoquinoline derivatives, see: Baba (1997 [triangle]); Baba et al. (1997 [triangle],1998 [triangle]); Koga et al. (1980 [triangle]); Qi et al. (2007 [triangle]). For a related structure, see: Czaun et al. (2002 [triangle]); For graph-set motifs, see: Etter et al. (1990 [triangle]).

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Object name is e-65-o2664-scheme1.jpg

Experimental

Crystal data

  • C21H25NO4
  • M r = 355.42
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2664-efi2.jpg
  • a = 10.8721 (4) Å
  • b = 16.1255 (7) Å
  • c = 11.0856 (4) Å
  • β = 100.682 (2)°
  • V = 1909.83 (13) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 296 K
  • 0.26 × 0.15 × 0.12 mm

Data collection

  • Bruker Kappa APEXII area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004 [triangle]) T min = 0.93, T max = 0.95
  • 14667 measured reflections
  • 3163 independent reflections
  • 2137 reflections with I > 2σ(I)
  • R int = 0.041

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.115
  • S = 1.02
  • 3163 reflections
  • 236 parameters
  • H-atom parameters constrained
  • Δρmax = 0.15 e Å−3
  • Δρmin = −0.15 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT-Plus (Bruker, 2004 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809039877/ci2916sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809039877/ci2916Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Some oxoquinoline derivatives viz. 8-difluoromethoxy-1-ethyl-6-fluoro-1,4-dihydro-7-[4-(2-methoxyphenyl)- 1-πiperazinyl]- 4-oxoquinoline-3-carboxylic acid (K-12), 7-(3,4-dehydro-4-phenyl-1-piperidinyl)-1,4-dihydro-6-fluoro-1-methyl- 8-trifluoromethyl-4-oxoquinoline-3-carboxylic acid (K-37), 8-difluoromethoxy-1,4-dihydro-6-fluoro-7-(3,4-dehydro-4-phenyl- 1-piperidinyl)-1-[4,(1,2,4-triazol-1-yl)methylphenyl]-4-oxoquinoline- 3-carboxylic acid (K-38) act as potent and selective inhibitor of human immunodeficiency virus type I (HIV-1) transcription (Baba, 1997; Baba et al., 1997,1998). Structure-activity relationships of antibacterial oxoquinolone-3-carboxylic acids have been studied (Koga et al., 1980). In view of the signficicant biological activitiy, precise single crystal structure determinations of these derivatives are expcted to provide insights in their design and function. The crystal structure of 1H-2-phenyl-3-hydroxy-4-oxoquinoline-dimethylsulfoxide has already been reported (Czaun et al., 2002). The expression, purification and crystallization of 1H-3-hydroxy-4-oxoquinoline 2,4-dioxygenase are reported elsewhere (Qi et al., 2007).

The dihydropyridine ring of the title molecule (Fig.1) adopts a flattened boat conformation. The cyclohexenone ring is in an envelope conformation with atom C4 at the flap. The 4-methoxyphenyl ring and the planar part of the dihydropyridine ring (C2/C7/C9/C10) are nearly perpendicular to each other, with a dihedral angle of 89.37 (6)°.

In the crystal structure, molecules are linked into a two-dimensional network (Fig.2) parallel to the (101) by N—H···O and O—H···O hydrogen bonds (Table 1). The two-deimensional layer, resembiling a corrugated sheet, contains R44(30) and R44(34) graph-set motifs (Etter et al., 1990) as its fundamental repeating units. It is observed that these rings are assembled through centrosymmetrically related pairs of molecules with no direct hydrogen bonding between them.

Experimental

A 50 ml round-bottomed flask was charged with 3-hydroxybenzaldehyde (1.221 g, 10 mmol), 5,5-dimethyl-1,3-cyclohexanedione (1.402 g, 10 mmol), ethyl acetoacetate (1.265 ml, 10 mmol) and ammonium acetate (0.771 g, 10 mmol) followed by ethanol (10 ml). The mixture was stirred at 343 K for 1.5 h and left aside for a day. The solid separated out was filtered and washed with ethanol-diethyl ether mixture (1:4). It was recrystalyzed from 100% chloroform. Light yellow prismatic crystals of the title compound were obtained by slow evaporation of a methonolic solution. Pale yellow crystals with slab morphology were obtained by slow evaporation of a methonol-chloroform solution.

Refinement

H atoms were positioned geometrically [O-H = 0.82 Å, N-H = 0.86 Å and C-H = 0.93–0.98 Å] and refined using a riding model with Uiso(H) = 1.2Ueq(C) and 1.2Ueq(O and Cmethyl).

Figures

Fig. 1.
The molecular structure of the title compound, with atom labels and 50% probability displacement ellipsoids for non-H atoms. H atoms have been omitted for clarity.
Fig. 2.
A view of the molecular aggregation down the a axis. Hydrogen bonds are shown as dashed lines. C-bound H atoms have been omitted for clarity.
Fig. 3.
A view of the molecular aggregation down the b axis. Hydrogen bonds are shown as dashed lines. C-bound H atoms have been omitted for clarity.

Crystal data

C21H25NO4F(000) = 760
Mr = 355.42Dx = 1.236 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 5123 reflections
a = 10.8721 (4) Åθ = 2.0–30.0°
b = 16.1255 (7) ŵ = 0.09 mm1
c = 11.0856 (4) ÅT = 296 K
β = 100.682 (2)°Prism, yellow
V = 1909.83 (13) Å30.26 × 0.15 × 0.12 mm
Z = 4

Data collection

Bruker Kappa APEXII area-detector diffractometer3163 independent reflections
Radiation source: fine-focus sealed tube2137 reflections with I > 2σ(I)
graphiteRint = 0.041
ω and [var phi] scansθmax = 24.5°, θmin = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)h = −12→12
Tmin = 0.93, Tmax = 0.95k = −18→17
14667 measured reflectionsl = −11→12

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.048P)2 + 0.4479P] where P = (Fo2 + 2Fc2)/3
3163 reflections(Δ/σ)max = 0.001
236 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = −0.15 e Å3

Special details

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)

xyzUiso*/Ueq
O9A1.01275 (14)0.04777 (9)0.71484 (12)0.0559 (4)
O6A1.21908 (13)0.29658 (10)0.59297 (11)0.0577 (4)
O9B0.84079 (15)−0.01070 (9)0.60571 (13)0.0618 (4)
O8C0.72595 (19)0.37790 (12)0.71929 (17)0.0969 (7)
H8C0.70980.40090.78040.145*
N10.85621 (15)0.18610 (10)0.34959 (13)0.0444 (4)
H10.79900.19330.28570.053*
C71.03735 (16)0.23880 (11)0.47694 (14)0.0346 (4)
C20.95697 (17)0.23874 (11)0.36798 (15)0.0365 (4)
C81.01637 (17)0.18488 (12)0.58296 (15)0.0376 (5)
H81.09620.15830.61760.045*
C90.92188 (17)0.11633 (11)0.53752 (15)0.0368 (4)
C61.14473 (17)0.29327 (12)0.49410 (15)0.0394 (5)
C100.84203 (17)0.12208 (12)0.42851 (15)0.0384 (5)
C9A0.91749 (19)0.04511 (13)0.61867 (17)0.0433 (5)
C41.04698 (18)0.37054 (12)0.29899 (16)0.0435 (5)
C8B0.8704 (2)0.28573 (13)0.65967 (17)0.0509 (6)
H8B0.82600.28930.57960.061*
C30.97318 (19)0.29188 (13)0.26167 (15)0.0471 (5)
H3A0.89130.30680.21590.057*
H3B1.01570.26000.20750.057*
C51.16617 (19)0.34564 (14)0.38772 (17)0.0537 (6)
H5A1.21990.31540.34240.064*
H5B1.21030.39560.41960.064*
C8A0.97467 (19)0.23549 (12)0.68484 (15)0.0421 (5)
C10A0.7372 (2)0.06394 (14)0.37939 (18)0.0536 (6)
H10A0.77070.01010.36750.080*
H10B0.69240.08450.30240.080*
H10C0.68130.06000.43680.080*
C8F1.0398 (2)0.23138 (15)0.80510 (17)0.0608 (6)
H8F1.11110.19860.82410.073*
C8C0.8307 (2)0.33082 (14)0.7515 (2)0.0608 (6)
C9B1.0157 (2)−0.01484 (16)0.8081 (2)0.0682 (7)
H91B1.0250−0.06940.77400.082*
H92B0.9384−0.01390.84000.082*
C4A1.0813 (2)0.41285 (15)0.18658 (18)0.0673 (7)
H41A1.12790.46250.21150.101*
H42A1.00630.42680.12980.101*
H43A1.13130.37590.14770.101*
C8E0.9988 (3)0.27565 (18)0.8960 (2)0.0777 (8)
H8E1.04220.27140.97630.093*
C8D0.8956 (3)0.32578 (17)0.8710 (2)0.0717 (8)
H8D0.86970.35590.93330.086*
C4B0.9704 (3)0.43009 (15)0.3613 (2)0.0796 (8)
H41B1.01810.47960.38440.119*
H42B0.95020.40430.43320.119*
H43B0.89470.44400.30560.119*
C9C1.1234 (3)0.0034 (2)0.9074 (2)0.0993 (11)
H91C1.1276−0.03740.97100.149*
H92C1.11300.05740.94070.149*
H93C1.19930.00220.87490.149*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O9A0.0679 (10)0.0550 (9)0.0430 (7)0.0030 (7)0.0057 (7)0.0178 (7)
O6A0.0501 (9)0.0749 (11)0.0390 (7)−0.0106 (8)−0.0157 (7)0.0038 (7)
O9B0.0681 (11)0.0521 (10)0.0667 (10)−0.0076 (8)0.0164 (8)0.0124 (8)
O8C0.1049 (15)0.1028 (16)0.0858 (13)0.0344 (13)0.0246 (11)−0.0337 (11)
N10.0460 (10)0.0493 (10)0.0313 (8)−0.0099 (8)−0.0099 (7)0.0028 (8)
C70.0365 (10)0.0380 (11)0.0272 (9)0.0017 (8)0.0006 (7)−0.0014 (8)
C20.0402 (11)0.0380 (11)0.0286 (9)−0.0024 (9)−0.0005 (8)−0.0028 (8)
C80.0390 (11)0.0427 (11)0.0282 (9)0.0027 (9)−0.0011 (8)0.0036 (8)
C90.0438 (11)0.0356 (11)0.0325 (9)0.0021 (9)0.0107 (8)−0.0012 (8)
C60.0375 (11)0.0456 (12)0.0312 (9)0.0008 (9)−0.0034 (8)−0.0018 (9)
C100.0438 (11)0.0374 (11)0.0338 (9)−0.0024 (9)0.0068 (8)−0.0046 (9)
C9A0.0479 (12)0.0432 (12)0.0418 (11)0.0067 (10)0.0160 (10)0.0002 (9)
C40.0519 (12)0.0440 (12)0.0312 (9)−0.0051 (10)−0.0009 (9)0.0020 (9)
C8B0.0619 (14)0.0548 (14)0.0351 (10)0.0008 (11)0.0063 (10)−0.0091 (10)
C30.0542 (13)0.0540 (13)0.0282 (9)−0.0119 (10)−0.0052 (9)0.0032 (9)
C50.0508 (13)0.0627 (14)0.0429 (11)−0.0151 (11)−0.0037 (10)0.0060 (10)
C8A0.0538 (13)0.0429 (12)0.0285 (9)−0.0071 (10)0.0046 (8)−0.0019 (8)
C10A0.0579 (14)0.0541 (14)0.0472 (11)−0.0153 (11)0.0058 (10)−0.0075 (10)
C8F0.0772 (16)0.0680 (15)0.0326 (11)−0.0053 (13)−0.0016 (10)−0.0034 (11)
C8C0.0738 (16)0.0540 (15)0.0586 (14)−0.0031 (13)0.0229 (12)−0.0155 (12)
C9B0.0835 (18)0.0674 (16)0.0571 (13)0.0206 (13)0.0220 (13)0.0296 (12)
C4A0.0850 (18)0.0689 (16)0.0438 (12)−0.0258 (14)0.0008 (11)0.0110 (11)
C8E0.109 (2)0.089 (2)0.0303 (11)−0.0111 (18)0.0015 (13)−0.0135 (12)
C8D0.101 (2)0.0724 (18)0.0468 (13)−0.0194 (16)0.0261 (14)−0.0260 (13)
C4B0.117 (2)0.0556 (16)0.0675 (15)0.0266 (15)0.0204 (15)0.0067 (13)
C9C0.0805 (19)0.148 (3)0.0679 (16)0.0255 (19)0.0092 (15)0.0560 (19)

Geometric parameters (Å, °)

O9A—C9A1.342 (2)C3—H3A0.97
O9A—C9B1.442 (2)C3—H3B0.97
O6A—C61.237 (2)C5—H5A0.97
O9B—C9A1.217 (2)C5—H5B0.97
O8C—C8C1.361 (3)C8A—C8F1.390 (3)
O8C—H8C0.82C10A—H10A0.96
N1—C21.371 (2)C10A—H10B0.96
N1—C101.380 (2)C10A—H10C0.96
N1—H10.86C8F—C8E1.374 (3)
C7—C21.353 (2)C8F—H8F0.93
C7—C61.445 (3)C8C—C8D1.383 (3)
C7—C81.513 (2)C9B—C9C1.480 (3)
C2—C31.494 (3)C9B—H91B0.97
C8—C91.529 (3)C9B—H92B0.97
C8—C8A1.529 (3)C4A—H41A0.96
C8—H80.98C4A—H42A0.96
C9—C101.354 (2)C4A—H43A0.96
C9—C9A1.465 (3)C8E—C8D1.369 (4)
C6—C51.503 (3)C8E—H8E0.93
C10—C10A1.498 (3)C8D—H8D0.93
C4—C31.517 (3)C4B—H41B0.96
C4—C4B1.518 (3)C4B—H42B0.96
C4—C4A1.526 (3)C4B—H43B0.96
C4—C51.528 (3)C9C—H91C0.96
C8B—C8A1.379 (3)C9C—H92C0.96
C8B—C8C1.383 (3)C9C—H93C0.96
C8B—H8B0.93
C9A—O9A—C9B117.31 (17)C4—C5—H5B108.6
C8C—O8C—H8C109.5H5A—C5—H5B107.6
C2—N1—C10123.30 (14)C8B—C8A—C8F118.38 (19)
C2—N1—H1118.4C8B—C8A—C8120.62 (15)
C10—N1—H1118.4C8F—C8A—C8120.99 (19)
C2—C7—C6119.35 (16)C10—C10A—H10A109.5
C2—C7—C8121.84 (17)C10—C10A—H10B109.5
C6—C7—C8118.79 (14)H10A—C10A—H10B109.5
C7—C2—N1119.95 (17)C10—C10A—H10C109.5
C7—C2—C3123.56 (17)H10A—C10A—H10C109.5
N1—C2—C3116.47 (14)H10B—C10A—H10C109.5
C7—C8—C9110.38 (14)C8E—C8F—C8A120.1 (2)
C7—C8—C8A112.04 (15)C8E—C8F—H8F120.0
C9—C8—C8A110.86 (15)C8A—C8F—H8F120.0
C7—C8—H8107.8O8C—C8C—C8B117.4 (2)
C9—C8—H8107.8O8C—C8C—C8D122.5 (2)
C8A—C8—H8107.8C8B—C8C—C8D120.1 (2)
C10—C9—C9A120.87 (17)O9A—C9B—C9C107.7 (2)
C10—C9—C8121.66 (16)O9A—C9B—H91B110.2
C9A—C9—C8117.43 (15)C9C—C9B—H91B110.2
O6A—C6—C7121.49 (17)O9A—C9B—H92B110.2
O6A—C6—C5120.01 (17)C9C—C9B—H92B110.2
C7—C6—C5118.50 (14)H91B—C9B—H92B108.5
C9—C10—N1119.23 (16)C4—C4A—H41A109.5
C9—C10—C10A126.89 (18)C4—C4A—H42A109.5
N1—C10—C10A113.86 (15)H41A—C4A—H42A109.5
O9B—C9A—O9A121.89 (18)C4—C4A—H43A109.5
O9B—C9A—C9127.35 (18)H41A—C4A—H43A109.5
O9A—C9A—C9110.76 (17)H42A—C4A—H43A109.5
C3—C4—C4B110.26 (19)C8D—C8E—C8F121.6 (2)
C3—C4—C4A110.37 (15)C8D—C8E—H8E119.2
C4B—C4—C4A109.04 (18)C8F—C8E—H8E119.2
C3—C4—C5107.36 (16)C8E—C8D—C8C118.8 (2)
C4B—C4—C5110.14 (17)C8E—C8D—H8D120.6
C4A—C4—C5109.66 (17)C8C—C8D—H8D120.6
C8A—C8B—C8C121.09 (19)C4—C4B—H41B109.5
C8A—C8B—H8B119.5C4—C4B—H42B109.5
C8C—C8B—H8B119.5H41B—C4B—H42B109.5
C2—C3—C4113.47 (14)C4—C4B—H43B109.5
C2—C3—H3A108.9H41B—C4B—H43B109.5
C4—C3—H3A108.9H42B—C4B—H43B109.5
C2—C3—H3B108.9C9B—C9C—H91C109.5
C4—C3—H3B108.9C9B—C9C—H92C109.5
H3A—C3—H3B107.7H91C—C9C—H92C109.5
C6—C5—C4114.60 (16)C9B—C9C—H93C109.5
C6—C5—H5A108.6H91C—C9C—H93C109.5
C4—C5—H5A108.6H92C—C9C—H93C109.5
C6—C5—H5B108.6
C6—C7—C2—N1178.61 (17)C10—C9—C9A—O9A173.47 (17)
C8—C7—C2—N1−3.0 (3)C8—C9—C9A—O9A−8.8 (2)
C6—C7—C2—C30.7 (3)C7—C2—C3—C4−26.3 (3)
C8—C7—C2—C3179.07 (17)N1—C2—C3—C4155.73 (17)
C10—N1—C2—C7−11.5 (3)C4B—C4—C3—C2−70.4 (2)
C10—N1—C2—C3166.61 (17)C4A—C4—C3—C2169.08 (18)
C2—C7—C8—C917.0 (2)C5—C4—C3—C249.6 (2)
C6—C7—C8—C9−164.56 (16)O6A—C6—C5—C4−150.90 (19)
C2—C7—C8—C8A−107.0 (2)C7—C6—C5—C430.1 (3)
C6—C7—C8—C8A71.4 (2)C3—C4—C5—C6−52.3 (2)
C7—C8—C9—C10−19.7 (2)C4B—C4—C5—C667.8 (2)
C8A—C8—C9—C10105.08 (19)C4A—C4—C5—C6−172.20 (18)
C7—C8—C9—C9A162.58 (16)C8C—C8B—C8A—C8F−0.2 (3)
C8A—C8—C9—C9A−72.7 (2)C8C—C8B—C8A—C8179.03 (19)
C2—C7—C6—O6A178.46 (18)C7—C8—C8A—C8B55.7 (2)
C8—C7—C6—O6A0.0 (3)C9—C8—C8A—C8B−68.1 (2)
C2—C7—C6—C5−2.5 (3)C7—C8—C8A—C8F−125.0 (2)
C8—C7—C6—C5179.01 (17)C9—C8—C8A—C8F111.2 (2)
C9A—C9—C10—N1−174.18 (17)C8B—C8A—C8F—C8E1.0 (3)
C8—C9—C10—N18.1 (3)C8—C8A—C8F—C8E−178.3 (2)
C9A—C9—C10—C10A4.3 (3)C8A—C8B—C8C—O8C−179.0 (2)
C8—C9—C10—C10A−173.38 (18)C8A—C8B—C8C—C8D−0.2 (4)
C2—N1—C10—C98.7 (3)C9A—O9A—C9B—C9C−176.61 (19)
C2—N1—C10—C10A−169.93 (18)C8A—C8F—C8E—C8D−1.3 (4)
C9B—O9A—C9A—O9B−4.7 (3)C8F—C8E—C8D—C8C0.8 (4)
C9B—O9A—C9A—C9175.31 (17)O8C—C8C—C8D—C8E178.7 (2)
C10—C9—C9A—O9B−6.5 (3)C8B—C8C—C8D—C8E0.0 (4)
C8—C9—C9A—O9B171.30 (19)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O8C—H8C···O9Bi0.822.052.835 (2)162
N1—H1···O6Aii0.862.162.970 (2)157

Symmetry codes: (i) −x+3/2, y+1/2, −z+3/2; (ii) x−1/2, −y+1/2, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2916).

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