organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Ethyl 5-cyano-8-nitro-2,3,4,4a,5,6-hexa­hydro-1H-pyrido[1,2-a]quinoline-5-carboxylate

aLaboratoire de Cristallographie et Physique Moléculaire, UFR–SSMT, Université de Cocody, 22 BP 582 Abidjan 22, Côte d'Ivoire, and bLaboratoire de Chimie Organique Structurale, UFR–SSMT, Université de Cocody, 22 BP 582 Abidjan 22, Côte d'Ivoire
*Correspondence e-mail: marcellin.yapo@univ-cocody.ci

(Received 27 May 2010; accepted 14 June 2010; online 23 June 2010)

In the title compound, C17H19N3O4, the piperidine ring adopts a chair conformation. The crystal structure features inversion dimers linked by pairs of weak C—H⋯N hydrogen bonds.

Related literature

For the therapeutic properties of quinoline derivatives, see: Dalla Via et al. (2008[Dalla Via, L., Gia, O., Gasparotto, V. & Ferlin, M. G. (2008). J. Med. Chem. 43, 429-434.]); Gasparotto et al. (2006[Gasparotto, V., Castalinolo, I., Chiarelotto, G., Pezzi, V., Montanaro, D., Brun, P., Palu, G., Viola, G. & Fer'lin, M. G. (2006). J. Med. Chem. 49, 1910-1915.]); Ferlin et al. (2000[Ferlin, M. G., Gatto, B., Chiarelotto, G. & Palumbo, M. (2000). Bioorg. Med. Chem. 8, 1415-1422.]). A similar heterocyclic structure, Mitomycin C, is used in cancer therapy, see: Crooke & Bradner (1976[Crooke, S. T. & Bradner, W. T. (1976). Cancer Treat. Rev. 3, 121-139.]); Danishefsky & Ciufolini (1984[Danishefsky, S. & Ciufolini, M. (1984). J. Am. Chem. Soc. 106, 6424-6425.]); Remers (1980[Remers, W. A. (1980). In Anticancer Agents Based on Natural Product Models, edited by J. M. Cassady & J. D. Duoros, p. 131. New York: Academic Press.]). For related structures, see: Zhuravleva et al. (2009[Zhuravleva, Y. A., Zimichev, A. V., Zemtsova, M. N., Rybakov, V. B. & Klimochkin, Y. N. (2009). Acta Cryst. E65, o2059.]); Oliveira et al. (2006[Oliveira, C. D., Romeiro, G. A., Skakle, J. M. S., Wardell, J. L. & Wardell, S. M. S. V. (2006). Acta Cryst. E62, o1492-o1493.]). For ring conformation analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For reference bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Wastson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C17H19N3O4

  • Mr = 329.36

  • Triclinic, [P \overline 1]

  • a = 8.8257 (4) Å

  • b = 9.2256 (5) Å

  • c = 10.5011 (6) Å

  • α = 88.246 (4)°

  • β = 75.089 (2)°

  • γ = 83.289 (3)°

  • V = 820.57 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 223 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Nonius KappaCCD diffractometer

  • 10064 measured reflections

  • 4189 independent reflections

  • 2794 reflections with I > 2σ(I)

  • Rint = 0.04

Refinement
  • R[F2 > 2σ(F2)] = 0.055

  • wR(F2) = 0.096

  • S = 1.04

  • 2503 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C7—H72⋯N3i 0.97 2.56 3.492 (3) 161
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: COLLECT (Nonius, 2001[Nonius (2001). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR2004 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003[Betteridge, P. W., Carruthers, J. R., Cooper, R. I., Prout, K. & Watkin, D. J. (2003). J. Appl. Cryst. 36, 1487.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: CRYSTALS.

Supporting information


Comment top

Tricyclic quinoline derivatives have diverse and important therapeutic properties (Dalla Via et al., 2008; Gasparotto et al., 2006; Ferlin et al., 2000). These heterocyclic are similar to Mitomycin C which is a powerful antibiotic used in cancerous chemotherapy (Crooke et al., 1976; Remers et al., 1980; Danishefsky et al., 1984). They are also used as intermediate compound to elaborate keratic fiber colorings. Here, we report the single X-ray determination of the title compound C17H19N3O4, (I), in order to have a best insight of its structure and then to undertake a study of its possible therapeutic activity. The molecular structure of this compound and its atomic labeling scheme are shown in Figure 1. The bond lenghts distances are within the accepted range (Allen et al., 1987). In (I), there are two coupled rings: quinoline and piperidine rings. The geometrical characteristics relating bond distances in quinoline ring are consistent and present no particularity with the recently reported (Oliveira et al., 2006; Zhuravleva et al., 2009). By least squares planes method, it is observed that carbon atom C8 deviates of -0.4074Å to quinoline cycle plane what proves that quinoline ring is not veritably plane. Concerning piperidine ring, it assumes a chair conformation which the puckering parameters (Cremer & Pople, 1975): θ=7.78°, Q=0.6147Å and Φ=42.46°. The crystal packing is due to the weak hydrogen bonds C-H···N which ensure crystal cohesion (Table 1 and Figure 2).

Related literature top

For the therapeutic properties of quinoline derivatives, see: Dalla Via et al. (2008); Gasparotto et al. (2006); Ferlin et al. (2000). For related structures, see: Zhuravleva et al. (2009); Oliveira et al. (2006). For ring conformation analysis, see: Cremer & Pople (1975). For reference bond lengths, see: Allen et al. (1987).

For related literature, see: Crooke & Bradner (1976); Danishefsky & Ciufolini (1984); Remers (1980).

Experimental top

3.5 g, 10 mmol of malonic arylidene was dissolved in 10 ml of dimethylformamide. The melange was heated to reflux during 24 h. After cooling to ambient temperature, 20 ml of water was added to the melange. After extraction to ethyl acetate (150 ml), the organic layers were dried on magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by chromatography on silica gel using hexane/ethyl acetate (80/20) to obtain yellow crystals with 45% yields. The melting point is 424 K

Refinement top

The H atoms were all located in a difference map and then treated as ridings atoms with C—H in the range 0.93–0.98Å and Uiso(H) in the range 1.2–1.5 times Ueq of the parent atom.

Computing details top

Data collection: COLLECT (Nonius, 2001); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).

Figures top
[Figure 1] Fig. 1. The title compound with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of (I). Hydrogen bonds C-H···N are shown as dashes lines: Symmetry code : (i) -x+1, -y+1, -z+1.
Ethyl 5-cyano-8-nitro-2,3,4,4a,5,6-hexahydro- 1H-pyrido[1,2-a]quinoline-5-carboxylate top
Crystal data top
C17H19N3O4Z = 2
Mr = 329.36F(000) = 348
Triclinic, P1Dx = 1.333 Mg m3
Hall symbol: -P 1Melting point: 424 K
a = 8.8257 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.2256 (5) ÅCell parameters from 10064 reflections
c = 10.5011 (6) Åθ = 2–29°
α = 88.246 (4)°µ = 0.10 mm1
β = 75.089 (2)°T = 223 K
γ = 83.289 (3)°Prism, yellow
V = 820.57 (8) Å30.20 × 0.20 × 0.20 mm
Data collection top
Nonius KappaCCD
diffractometer
Rint = 0.04
Graphite monochromatorθmax = 29.1°, θmin = 2.0°
ϕ and ω scansh = 012
10064 measured reflectionsk = 1112
4189 independent reflectionsl = 1314
2794 reflections with I > 2σ(I)
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.055H-atom parameters constrained
wR(F2) = 0.096 w = 1/[σ2(F2) + (0.02P)2 + 0.5P],
where P = (max(Fo2,0) + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.000163
2503 reflectionsΔρmax = 0.21 e Å3
217 parametersΔρmin = 0.26 e Å3
0 restraints
Crystal data top
C17H19N3O4γ = 83.289 (3)°
Mr = 329.36V = 820.57 (8) Å3
Triclinic, P1Z = 2
a = 8.8257 (4) ÅMo Kα radiation
b = 9.2256 (5) ŵ = 0.10 mm1
c = 10.5011 (6) ÅT = 223 K
α = 88.246 (4)°0.20 × 0.20 × 0.20 mm
β = 75.089 (2)°
Data collection top
Nonius KappaCCD
diffractometer
2794 reflections with I > 2σ(I)
10064 measured reflectionsRint = 0.04
4189 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0550 restraints
wR(F2) = 0.096H-atom parameters constrained
S = 1.04Δρmax = 0.21 e Å3
2503 reflectionsΔρmin = 0.26 e Å3
217 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.70920 (19)0.86006 (18)0.50748 (17)0.0241
N10.70324 (17)0.85963 (14)0.63954 (14)0.0268
O30.66155 (17)0.46173 (14)0.84947 (13)0.0393
C90.7451 (2)0.72488 (18)0.70764 (17)0.0256
C20.6873 (2)0.99129 (19)0.43830 (18)0.0287
C60.7271 (2)0.72669 (18)0.43802 (17)0.0269
C50.7160 (2)0.72795 (19)0.30929 (18)0.0308
C40.6920 (2)0.8595 (2)0.24574 (17)0.0311
O40.8187 (2)0.35165 (15)0.66714 (15)0.0548
O20.6821 (2)0.74186 (19)0.05771 (16)0.0639
C30.6790 (2)0.99068 (19)0.30939 (18)0.0308
C70.7604 (2)0.58338 (19)0.50323 (18)0.0325
C80.6879 (2)0.59435 (18)0.65159 (17)0.0278
C100.9210 (2)0.7072 (2)0.70064 (19)0.0327
N30.3802 (2)0.63652 (18)0.69548 (19)0.0450
N20.6797 (2)0.8591 (2)0.11110 (17)0.0436
O10.6673 (2)0.97711 (19)0.05381 (15)0.0652
C130.7303 (2)0.98771 (19)0.70769 (18)0.0310
C170.5143 (2)0.61781 (18)0.67811 (19)0.0322
C120.9039 (2)0.9820 (2)0.70523 (19)0.0346
C140.7321 (2)0.45278 (19)0.72194 (19)0.0328
C110.9606 (2)0.8393 (2)0.7643 (2)0.0358
C150.6946 (3)0.3372 (2)0.9327 (2)0.0461
C160.8465 (4)0.3441 (3)0.9667 (3)0.0711
H910.68740.73640.80090.0307*
H510.72700.63930.26400.0374*
H310.66391.07870.26400.0358*
H710.87510.55680.48750.0395*
H720.71930.50650.46550.0388*
H1010.94540.61730.74600.0386*
H1020.98060.70000.60830.0399*
H1220.91911.06530.75430.0424*
H1210.96560.98900.61380.0425*
H1121.07370.83120.75310.0436*
H1110.90820.84050.85860.0444*
H1520.60750.34761.01240.0547*
H1510.69600.24670.88450.0545*
H1620.86190.26581.02690.0858*
H1610.84530.43661.00860.0858*
H1630.93460.33280.88750.0858*
H210.67831.08100.48140.0340*
H1310.66790.98830.79850.0380*
H1320.69901.07600.66390.0380*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0202 (8)0.0264 (9)0.0259 (9)0.0011 (6)0.0068 (7)0.0010 (7)
N10.0338 (9)0.0213 (7)0.0269 (8)0.0003 (6)0.0122 (7)0.0028 (6)
O30.0480 (9)0.0337 (7)0.0313 (8)0.0038 (6)0.0057 (6)0.0066 (6)
C90.0293 (9)0.0242 (8)0.0237 (9)0.0009 (7)0.0087 (7)0.0007 (7)
C20.0264 (9)0.0269 (9)0.0316 (10)0.0020 (7)0.0061 (8)0.0012 (7)
C60.0268 (9)0.0274 (9)0.0258 (9)0.0008 (7)0.0066 (7)0.0000 (7)
C50.0332 (10)0.0331 (10)0.0262 (9)0.0035 (8)0.0076 (8)0.0024 (7)
C40.0301 (10)0.0422 (11)0.0206 (9)0.0055 (8)0.0058 (7)0.0036 (7)
O40.0801 (12)0.0323 (8)0.0403 (9)0.0185 (8)0.0056 (8)0.0011 (6)
O20.0985 (15)0.0666 (11)0.0350 (9)0.0240 (10)0.0255 (9)0.0007 (8)
C30.0245 (9)0.0345 (10)0.0313 (10)0.0025 (7)0.0048 (8)0.0086 (8)
C70.0452 (11)0.0265 (9)0.0259 (10)0.0021 (8)0.0115 (9)0.0037 (7)
C80.0326 (10)0.0233 (9)0.0276 (10)0.0006 (7)0.0097 (8)0.0001 (7)
C100.0302 (10)0.0314 (10)0.0361 (11)0.0007 (8)0.0101 (8)0.0039 (8)
N30.0402 (11)0.0384 (10)0.0596 (12)0.0061 (8)0.0174 (9)0.0034 (8)
N20.0455 (11)0.0574 (12)0.0267 (9)0.0062 (9)0.0076 (8)0.0059 (8)
O10.0931 (14)0.0654 (11)0.0342 (9)0.0056 (10)0.0195 (9)0.0154 (8)
C130.0372 (11)0.0257 (9)0.0320 (10)0.0002 (8)0.0132 (8)0.0046 (7)
C170.0422 (12)0.0223 (9)0.0349 (10)0.0051 (8)0.0141 (9)0.0009 (7)
C120.0362 (11)0.0338 (10)0.0358 (11)0.0078 (8)0.0110 (9)0.0017 (8)
C140.0400 (11)0.0265 (9)0.0321 (10)0.0015 (8)0.0105 (9)0.0009 (8)
C110.0282 (10)0.0431 (11)0.0378 (11)0.0062 (8)0.0108 (8)0.0019 (9)
C150.0573 (14)0.0401 (12)0.0364 (12)0.0018 (10)0.0088 (10)0.0141 (9)
C160.0735 (19)0.086 (2)0.0595 (17)0.0018 (15)0.0330 (15)0.0224 (14)
Geometric parameters (Å, º) top
C1—N11.374 (2)C7—H720.971
C1—C21.412 (2)C8—C171.476 (3)
C1—C61.422 (2)C8—C141.541 (2)
N1—C91.472 (2)C10—C111.525 (3)
N1—C131.474 (2)C10—H1010.973
O3—C141.324 (2)C10—H1020.977
O3—C151.469 (2)N3—C171.143 (2)
C9—C81.546 (2)N2—O11.235 (2)
C9—C101.524 (3)C13—C121.520 (3)
C9—H910.983C13—H1310.970
C2—C31.375 (3)C13—H1320.970
C2—H210.941C12—C111.524 (3)
C6—C51.380 (2)C12—H1220.979
C6—C71.504 (2)C12—H1210.979
C5—C41.388 (3)C11—H1120.969
C5—H510.941C11—H1110.979
C4—C31.379 (3)C15—C161.482 (4)
C4—N21.446 (2)C15—H1520.979
O4—C141.194 (2)C15—H1510.987
O2—N21.229 (2)C16—H1620.966
C3—H310.942C16—H1610.969
C7—C81.526 (2)C16—H1630.980
C7—H710.985
N1—C1—C2121.61 (15)C11—C10—H101111.3
N1—C1—C6120.57 (15)C9—C10—H102109.0
C2—C1—C6117.69 (16)C11—C10—H102109.9
C1—N1—C9121.40 (13)H101—C10—H102109.1
C1—N1—C13122.69 (14)C4—N2—O2119.05 (17)
C9—N1—C13109.99 (13)C4—N2—O1118.60 (18)
C14—O3—C15117.40 (15)O2—N2—O1122.36 (18)
N1—C9—C8109.45 (14)N1—C13—C12110.21 (14)
N1—C9—C10110.06 (14)N1—C13—H131109.3
C8—C9—C10114.36 (14)C12—C13—H131109.3
N1—C9—H91107.0N1—C13—H132109.3
C8—C9—H91108.0C12—C13—H132109.3
C10—C9—H91107.7H131—C13—H132109.4
C1—C2—C3121.40 (16)C8—C17—N3178.4 (2)
C1—C2—H21119.3C13—C12—C11110.80 (15)
C3—C2—H21119.3C13—C12—H122109.2
C1—C6—C5120.13 (16)C11—C12—H122110.4
C1—C6—C7120.45 (15)C13—C12—H121109.0
C5—C6—C7119.41 (15)C11—C12—H121109.0
C6—C5—C4120.19 (16)H122—C12—H121108.5
C6—C5—H51119.8C8—C14—O3110.12 (15)
C4—C5—H51120.0C8—C14—O4123.73 (18)
C5—C4—C3120.93 (17)O3—C14—O4126.15 (17)
C5—C4—N2119.57 (17)C10—C11—C12111.70 (16)
C3—C4—N2119.49 (17)C10—C11—H112108.7
C4—C3—C2119.60 (16)C12—C11—H112110.4
C4—C3—H31119.5C10—C11—H111109.4
C2—C3—H31120.9C12—C11—H111107.7
C6—C7—C8110.18 (14)H112—C11—H111108.9
C6—C7—H71110.2O3—C15—C16110.69 (19)
C8—C7—H71108.6O3—C15—H152104.8
C6—C7—H72110.0C16—C15—H152110.0
C8—C7—H72110.7O3—C15—H151108.1
H71—C7—H72107.2C16—C15—H151111.3
C9—C8—C7109.74 (14)H152—C15—H151111.7
C9—C8—C17108.75 (14)C15—C16—H162109.3
C7—C8—C17109.52 (15)C15—C16—H161110.0
C9—C8—C14109.75 (14)H162—C16—H161109.0
C7—C8—C14111.10 (14)C15—C16—H163110.6
C17—C8—C14107.93 (15)H162—C16—H163108.3
C9—C10—C11109.16 (14)H161—C16—H163109.6
C9—C10—H101108.3
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H72···N3i0.972.563.492 (3)161
Symmetry code: (i) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC17H19N3O4
Mr329.36
Crystal system, space groupTriclinic, P1
Temperature (K)223
a, b, c (Å)8.8257 (4), 9.2256 (5), 10.5011 (6)
α, β, γ (°)88.246 (4), 75.089 (2), 83.289 (3)
V3)820.57 (8)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
10064, 4189, 2794
Rint0.04
(sin θ/λ)max1)0.683
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.055, 0.096, 1.04
No. of reflections2503
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.26

Computer programs: COLLECT (Nonius, 2001), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR2004 (Burla et al., 2005), CRYSTALS (Betteridge et al., 2003), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H72···N3i0.972.563.492 (3)161
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

The authors wish to thank the Laboratoire de Physique des Inter­actions Ioniques et Moléculaires of Provence University (France) for the use of the diffractometer.

References

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