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Acta Crystallogr Sect E Struct Rep Online. 2010 October 1; 66(Pt 10): o2604.
Published online 2010 September 25. doi:  10.1107/S1600536810032824
PMCID: PMC2983386

Methyl 7-oxo-12-propyl­amino-13-nitro­deisopropyl­dehydro­abietate

Abstract

In the title compound, C21H28N2O5 (systematic name: methyl 1,4a-dimethyl-7-nitro-9-oxo-6-propyl­amino-1,2,3,4,4a,9,10,10a-octa­hydro­phenanthrene-1-carboxyl­ate) the cyclo­hexane ring (A) and the central cyclo­hexene ring (B) exist at a trans ring junction, with the two methyl groups in the axial positions of the six-membered rings. Ring A has a chair conformation and ring B a half-chair conformation. An intra­molecular N—H(...)O hydrogen bond occurs. The crystal structure is stabilized by inter­molecular C—H(...)O and N—H(...)O inter­actions.

Related literature

For inhibition of viruses by resin acid derivatives, see: Fonseca et al. (2004 [triangle]); Gigante et al. (2003 [triangle]). For related structures, see: Hamodrakas et al. (1978 [triangle]); Silvestre et al. (1998 [triangle]).

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Object name is e-66-o2604-scheme1.jpg

Experimental

Crystal data

  • C21H28N2O5
  • M r = 388.45
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2604-efi1.jpg
  • a = 8.2915 (15) Å
  • b = 11.344 (2) Å
  • c = 20.288 (4) Å
  • V = 1908.3 (6) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 223 K
  • 0.40 × 0.18 × 0.14 mm

Data collection

  • Rigaku Saturn diffractometer
  • Absorption correction: multi-scan (Jacobson, 1998 [triangle]) T min = 0.956, T max = 0.987
  • 9263 measured reflections
  • 2492 independent reflections
  • 2249 reflections with I > 2σ(I)
  • R int = 0.047

Refinement

  • R[F 2 > 2σ(F 2)] = 0.061
  • wR(F 2) = 0.122
  • S = 1.19
  • 2492 reflections
  • 262 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.16 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: CrystalClear (Rigaku, 1999 [triangle]); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku/MSC, 2000 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810032824/ng5010sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810032824/ng5010Isup2.hkl

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

Acknowledgments

The authors thank the National Natural Science Foundation of China (No. 20762001), Guangxi’s Medicine Talented Persons Small Highland Foundation (0808) and the Guangxi Department of Education research project (200911MS281, 200911MS282) for support.

supplementary crystallographic information

Comment

As the main components of rosin, abietic acid and dehydroabietic acid are tricyclic diterpene carboxylic acids. It have been demonstrated that resin acid derivatives exhibit inhibition activity against viruses by recent works (Gigante et al., 2003; Fonseca et al., 2004), which prompted us to synthesis of the title compound. In the cation of the title compounds (Fig.1), rings A (atoms C9—C14) and rings B (atoms C5—C10) demonstrate a trans ring junction with the torsion angles showing classical chair and halfchair conformations for rings A and B, respectively. There are two methyl groups in the axial positions of the six-membered rings and the overall geometric parameters of the title compound are comparable to those of 12-acetyl-dehydroabietate (Silvestre, et al., 1998) and methyl dehydroabietate (Hamodrakas, et al., 1978), apart from the substituted nitro group and propylamino at the benzene ring.

It should be noted that there are weak intermolecular C—H···O and N—H···O hydrogen bonds in the packing view, which link the molecules into a one-dimensional chain to stabilize the structure (Fig. 2).

The absolute configuration of the title compound could not determined from anomalous scattering effects because none heavier atoms than Si are present. However, NMR studies of analgous compounds suggest that the configuration is retained through the course of the reaction.Therefore, the absolute configuration of the title compound is assumed from the known absolute configuration of methyl dehydroabietate (Hamodrakas, et al., 1978).

Experimental

Methyl 7-oxo-12-bromo-13-nitro-deisopropyldehydroabietate (2.5 mmol), potassium carbonate (1.0 mmol), cuprous chloride (2.0 mmol) were added to 15 ml DMF. After stirring for 10 min, n-propylamine (2.5 mmol) was added drop-wise. The resultant solution was refluxed for 4 h, and then plenty of ice water was added, a lot of orange-yellow solid was precipitated, filtered, washed with water, and then dried. Upon recrystallization from ethanol, pale orange crystls were obtained (Yield 78.9%, m.p. 455–456 k).

Refinement

H atoms bound to C atoms were positioned geometrically and included in the refinement in the riding-model approximation [d(C—H) = 0.95 and 0.99 Å for aromatic and CH2 groups, respectively, and with Uiso(H) = 1.2Ueq (C) for all others. 1443 Friedel pairs were merged.

Figures

Fig. 1.
The structure of the title compound showing 50% probability displacement ellipsoids and the atom labelling scheme. H atoms are represented by small spheres of arbitrary radius.
Fig. 2.
Packing diagram with H bonds indicated by dashed lines.

Crystal data

C21H28N2O5F(000) = 832
Mr = 388.45Dx = 1.352 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71075 Å
Hall symbol: P 2ac 2abCell parameters from 6184 reflections
a = 8.2915 (15) Åθ = 3.0–27.5°
b = 11.344 (2) ŵ = 0.10 mm1
c = 20.288 (4) ÅT = 223 K
V = 1908.3 (6) Å3Block, yellow
Z = 40.40 × 0.18 × 0.14 mm

Data collection

Rigaku Saturn diffractometer2492 independent reflections
Radiation source: fine-focus sealed tube2249 reflections with I > 2σ(I)
graphiteRint = 0.047
Detector resolution: 14.63 pixels mm-1θmax = 27.5°, θmin = 3.0°
ω scansh = −10→10
Absorption correction: multi-scan (Jacobson, 1998)k = −13→14
Tmin = 0.956, Tmax = 0.987l = −26→18
9263 measured reflections

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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.122H atoms treated by a mixture of independent and constrained refinement
S = 1.19w = 1/[σ2(Fo2) + (0.040P)2 + 0.3656P] where P = (Fo2 + 2Fc2)/3
2492 reflections(Δ/σ)max < 0.001
262 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = −0.20 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
O1−0.0800 (3)0.5805 (2)0.50671 (13)0.0413 (7)
O20.1082 (3)0.8201 (2)0.32927 (14)0.0428 (7)
O30.3574 (3)0.8723 (2)0.31899 (13)0.0374 (6)
O40.1294 (4)0.3814 (3)0.75394 (15)0.0594 (9)
O50.2387 (3)0.5514 (2)0.72342 (13)0.0393 (6)
N10.5809 (3)0.7320 (3)0.37018 (15)0.0301 (7)
H1A0.552 (4)0.784 (3)0.3368 (19)0.034 (10)*
N20.2510 (3)0.8110 (3)0.34543 (14)0.0296 (6)
C10.4799 (4)0.5968 (3)0.45202 (16)0.0273 (7)
H1B0.58470.56720.45830.033*
C20.4562 (4)0.6880 (3)0.40463 (16)0.0261 (7)
C30.2948 (4)0.7264 (3)0.39580 (16)0.0264 (7)
C40.1710 (4)0.6826 (3)0.43411 (16)0.0272 (7)
H40.06620.71260.42840.033*
C50.1976 (4)0.5958 (3)0.48066 (16)0.0259 (7)
C60.3556 (4)0.5500 (3)0.48907 (15)0.0249 (7)
C70.0594 (4)0.5512 (3)0.51883 (17)0.0306 (8)
C80.0933 (4)0.4657 (3)0.57383 (17)0.0291 (7)
H8A0.06260.38630.55950.035*
H8B0.02620.48630.61190.035*
C90.2698 (4)0.4647 (3)0.59499 (15)0.0255 (7)
H90.29300.54550.61060.031*
C100.2965 (4)0.3826 (3)0.65599 (17)0.0285 (7)
C110.4779 (4)0.3807 (3)0.67347 (18)0.0336 (8)
H11A0.50990.45850.68990.040*
H11B0.49620.32330.70880.040*
C120.5822 (5)0.3488 (4)0.61471 (19)0.0382 (9)
H12A0.55360.26970.59920.046*
H12B0.69580.34770.62810.046*
C130.5592 (4)0.4378 (3)0.55853 (18)0.0339 (8)
H13A0.62850.41540.52140.041*
H13B0.59330.51600.57370.041*
C140.3833 (4)0.4444 (3)0.53470 (16)0.0264 (7)
C150.7445 (4)0.6817 (3)0.36949 (17)0.0294 (7)
H15A0.77710.66390.41480.035*
H15B0.81970.74060.35200.035*
C160.7571 (4)0.5698 (3)0.32818 (18)0.0346 (8)
H16A0.73190.58810.28210.042*
H16B0.67810.51200.34390.042*
C170.9260 (4)0.5170 (3)0.33244 (19)0.0364 (9)
H17A1.00490.57620.32020.055*
H17B0.93400.45040.30260.055*
H17C0.94650.49090.37720.055*
C180.2105 (4)0.4364 (3)0.71584 (18)0.0326 (8)
C190.1741 (5)0.6042 (4)0.7827 (2)0.0500 (11)
H19A0.05740.59890.78210.075*
H19B0.20610.68640.78480.075*
H19C0.21560.56270.82100.075*
C200.2305 (5)0.2577 (3)0.6477 (2)0.0412 (9)
H20A0.24490.21430.68850.062*
H20B0.28820.21820.61250.062*
H20C0.11670.26130.63690.062*
C210.3452 (5)0.3342 (3)0.49327 (18)0.0376 (9)
H21A0.41100.33440.45380.056*
H21B0.23210.33470.48110.056*
H21C0.36840.26400.51890.056*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0236 (12)0.0637 (19)0.0365 (15)0.0019 (13)0.0007 (11)0.0130 (14)
O20.0259 (13)0.0531 (16)0.0492 (17)0.0044 (13)−0.0076 (13)0.0179 (14)
O30.0346 (13)0.0395 (14)0.0382 (15)−0.0046 (12)0.0018 (12)0.0126 (12)
O40.077 (2)0.0477 (17)0.053 (2)0.0017 (17)0.0362 (18)0.0111 (15)
O50.0461 (15)0.0413 (14)0.0305 (14)0.0002 (13)0.0097 (12)−0.0060 (12)
N10.0234 (14)0.0372 (17)0.0299 (16)−0.0009 (13)0.0009 (12)0.0100 (13)
N20.0298 (15)0.0315 (15)0.0275 (14)0.0017 (14)−0.0013 (13)0.0004 (13)
C10.0216 (14)0.0353 (19)0.0248 (17)0.0028 (14)0.0011 (13)0.0005 (15)
C20.0239 (16)0.0304 (18)0.0239 (17)−0.0055 (15)0.0017 (13)−0.0018 (15)
C30.0275 (16)0.0288 (17)0.0228 (16)0.0026 (15)−0.0052 (13)0.0015 (14)
C40.0210 (15)0.0338 (18)0.0268 (17)−0.0007 (15)0.0008 (13)−0.0020 (14)
C50.0214 (14)0.0314 (17)0.0250 (17)0.0004 (14)0.0019 (12)−0.0001 (14)
C60.0251 (15)0.0306 (17)0.0191 (15)−0.0040 (14)−0.0012 (13)−0.0021 (13)
C70.0255 (16)0.039 (2)0.0271 (18)−0.0021 (16)0.0007 (14)−0.0005 (16)
C80.0255 (16)0.0344 (19)0.0274 (18)−0.0031 (15)0.0029 (13)0.0044 (15)
C90.0261 (17)0.0260 (17)0.0245 (16)0.0017 (15)0.0013 (13)−0.0003 (13)
C100.0323 (17)0.0271 (17)0.0261 (17)0.0002 (15)0.0035 (14)0.0041 (14)
C110.0343 (18)0.039 (2)0.0271 (18)0.0047 (16)0.0000 (15)0.0068 (16)
C120.0332 (19)0.046 (2)0.036 (2)0.0116 (18)0.0032 (17)0.0074 (17)
C130.0305 (17)0.042 (2)0.0290 (19)0.0076 (17)0.0032 (14)0.0060 (16)
C140.0274 (16)0.0258 (17)0.0259 (17)0.0019 (15)0.0030 (13)−0.0010 (14)
C150.0202 (15)0.0356 (19)0.0326 (18)0.0007 (16)−0.0007 (14)0.0027 (15)
C160.0302 (17)0.040 (2)0.0332 (19)−0.0007 (17)0.0017 (15)−0.0035 (16)
C170.0303 (17)0.041 (2)0.038 (2)0.0018 (17)0.0047 (16)−0.0022 (17)
C180.0332 (18)0.0372 (19)0.0272 (18)0.0019 (16)0.0003 (14)0.0058 (16)
C190.061 (3)0.059 (3)0.030 (2)0.010 (2)0.007 (2)−0.013 (2)
C200.051 (2)0.0318 (19)0.041 (2)0.0020 (19)0.0046 (19)0.0052 (17)
C210.051 (2)0.035 (2)0.0275 (19)−0.0011 (18)0.0040 (17)−0.0043 (16)

Geometric parameters (Å, °)

O1—C71.227 (4)C10—C111.545 (5)
O2—N21.233 (3)C11—C121.517 (5)
O3—N21.245 (3)C11—H11A0.9800
O4—C181.200 (4)C11—H11B0.9800
O5—C181.334 (4)C12—C131.535 (5)
O5—C191.447 (4)C12—H12A0.9800
N1—C21.344 (4)C12—H12B0.9800
N1—C151.472 (4)C13—C141.539 (5)
N1—H1A0.93 (4)C13—H13A0.9800
N2—C31.448 (4)C13—H13B0.9800
C1—C61.382 (4)C14—C211.540 (5)
C1—C21.426 (5)C15—C161.525 (5)
C1—H1B0.9400C15—H15A0.9800
C2—C31.418 (4)C15—H15B0.9800
C3—C41.380 (5)C16—C171.525 (5)
C4—C51.383 (5)C16—H16A0.9800
C4—H40.9400C16—H16B0.9800
C5—C61.419 (4)C17—H17A0.9700
C5—C71.472 (4)C17—H17B0.9700
C6—C141.531 (5)C17—H17C0.9700
C7—C81.505 (5)C19—H19A0.9700
C8—C91.525 (4)C19—H19B0.9700
C8—H8A0.9800C19—H19C0.9700
C8—H8B0.9800C20—H20A0.9700
C9—C141.560 (4)C20—H20B0.9700
C9—C101.564 (5)C20—H20C0.9700
C9—H90.9900C21—H21A0.9700
C10—C201.529 (5)C21—H21B0.9700
C10—C181.535 (5)C21—H21C0.9700
C18—O5—C19115.8 (3)C11—C12—H12B109.5
C2—N1—C15124.8 (3)C13—C12—H12B109.5
C2—N1—H1A115 (2)H12A—C12—H12B108.1
C15—N1—H1A118 (2)C12—C13—C14112.5 (3)
O2—N2—O3121.3 (3)C12—C13—H13A109.1
O2—N2—C3119.0 (3)C14—C13—H13A109.1
O3—N2—C3119.7 (3)C12—C13—H13B109.1
C6—C1—C2122.8 (3)C14—C13—H13B109.1
C6—C1—H1B118.6H13A—C13—H13B107.8
C2—C1—H1B118.6C6—C14—C13111.8 (3)
N1—C2—C3123.1 (3)C6—C14—C21105.9 (3)
N1—C2—C1120.9 (3)C13—C14—C21109.0 (3)
C3—C2—C1116.0 (3)C6—C14—C9105.6 (3)
C4—C3—C2121.4 (3)C13—C14—C9109.4 (3)
C4—C3—N2116.7 (3)C21—C14—C9115.1 (3)
C2—C3—N2122.0 (3)N1—C15—C16113.0 (3)
C3—C4—C5121.5 (3)N1—C15—H15A109.0
C3—C4—H4119.3C16—C15—H15A109.0
C5—C4—H4119.3N1—C15—H15B109.0
C4—C5—C6119.3 (3)C16—C15—H15B109.0
C4—C5—C7118.7 (3)H15A—C15—H15B107.8
C6—C5—C7122.0 (3)C15—C16—C17111.0 (3)
C1—C6—C5118.9 (3)C15—C16—H16A109.4
C1—C6—C14121.1 (3)C17—C16—H16A109.4
C5—C6—C14119.8 (3)C15—C16—H16B109.4
O1—C7—C5122.3 (3)C17—C16—H16B109.4
O1—C7—C8119.9 (3)H16A—C16—H16B108.0
C5—C7—C8117.8 (3)C16—C17—H17A109.5
C7—C8—C9113.1 (3)C16—C17—H17B109.5
C7—C8—H8A109.0H17A—C17—H17B109.5
C9—C8—H8A109.0C16—C17—H17C109.5
C7—C8—H8B109.0H17A—C17—H17C109.5
C9—C8—H8B109.0H17B—C17—H17C109.5
H8A—C8—H8B107.8O4—C18—O5122.2 (4)
C8—C9—C14111.1 (3)O4—C18—C10124.3 (3)
C8—C9—C10111.3 (3)O5—C18—C10113.5 (3)
C14—C9—C10116.6 (3)O5—C19—H19A109.5
C8—C9—H9105.7O5—C19—H19B109.5
C14—C9—H9105.7H19A—C19—H19B109.5
C10—C9—H9105.7O5—C19—H19C109.5
C20—C10—C18106.8 (3)H19A—C19—H19C109.5
C20—C10—C11111.1 (3)H19B—C19—H19C109.5
C18—C10—C11106.1 (3)C10—C20—H20A109.5
C20—C10—C9114.5 (3)C10—C20—H20B109.5
C18—C10—C9108.9 (3)H20A—C20—H20B109.5
C11—C10—C9109.2 (3)C10—C20—H20C109.5
C12—C11—C10112.2 (3)H20A—C20—H20C109.5
C12—C11—H11A109.2H20B—C20—H20C109.5
C10—C11—H11A109.2C14—C21—H21A109.5
C12—C11—H11B109.2C14—C21—H21B109.5
C10—C11—H11B109.2H21A—C21—H21B109.5
H11A—C11—H11B107.9C14—C21—H21C109.5
C11—C12—C13110.8 (3)H21A—C21—H21C109.5
C11—C12—H12A109.5H21B—C21—H21C109.5
C13—C12—H12A109.5
C15—N1—C2—C3−169.2 (3)C14—C9—C10—C18164.2 (3)
C15—N1—C2—C19.6 (5)C8—C9—C10—C11177.6 (3)
C6—C1—C2—N1179.2 (3)C14—C9—C10—C1148.8 (4)
C6—C1—C2—C3−2.0 (5)C20—C10—C11—C1273.9 (4)
N1—C2—C3—C4−177.2 (3)C18—C10—C11—C12−170.4 (3)
C1—C2—C3—C44.0 (5)C9—C10—C11—C12−53.2 (4)
N1—C2—C3—N24.2 (5)C10—C11—C12—C1359.8 (4)
C1—C2—C3—N2−174.6 (3)C11—C12—C13—C14−59.2 (4)
O2—N2—C3—C4−15.9 (5)C1—C6—C14—C1326.8 (4)
O3—N2—C3—C4164.6 (3)C5—C6—C14—C13−157.9 (3)
O2—N2—C3—C2162.7 (3)C1—C6—C14—C21−91.8 (4)
O3—N2—C3—C2−16.7 (5)C5—C6—C14—C2183.5 (4)
C2—C3—C4—C5−3.0 (5)C1—C6—C14—C9145.7 (3)
N2—C3—C4—C5175.7 (3)C5—C6—C14—C9−39.0 (4)
C3—C4—C5—C6−0.3 (5)C12—C13—C14—C6168.4 (3)
C3—C4—C5—C7−178.7 (3)C12—C13—C14—C21−74.8 (4)
C2—C1—C6—C5−1.1 (5)C12—C13—C14—C951.8 (4)
C2—C1—C6—C14174.2 (3)C8—C9—C14—C662.4 (3)
C4—C5—C6—C12.3 (5)C10—C9—C14—C6−168.7 (3)
C7—C5—C6—C1−179.4 (3)C8—C9—C14—C13−177.2 (3)
C4—C5—C6—C14−173.1 (3)C10—C9—C14—C13−48.3 (4)
C7—C5—C6—C145.2 (5)C8—C9—C14—C21−54.0 (4)
C4—C5—C7—O16.8 (5)C10—C9—C14—C2174.9 (4)
C6—C5—C7—O1−171.5 (3)C2—N1—C15—C1675.2 (4)
C4—C5—C7—C8−174.0 (3)N1—C15—C16—C17−176.5 (3)
C6—C5—C7—C87.7 (5)C19—O5—C18—O43.8 (5)
O1—C7—C8—C9−164.0 (3)C19—O5—C18—C10−173.9 (3)
C5—C7—C8—C916.8 (4)C20—C10—C18—O411.4 (5)
C7—C8—C9—C14−53.1 (4)C11—C10—C18—O4−107.1 (4)
C7—C8—C9—C10175.2 (3)C9—C10—C18—O4135.5 (4)
C8—C9—C10—C2052.4 (4)C20—C10—C18—O5−170.8 (3)
C14—C9—C10—C20−76.4 (4)C11—C10—C18—O570.6 (4)
C8—C9—C10—C18−67.0 (3)C9—C10—C18—O5−46.8 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···O30.93 (4)1.94 (4)2.654 (4)133 (3)
C8—H8B···O3i0.982.553.454 (4)154
C15—H15A···O1ii0.982.403.344 (4)161

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NG5010).

References

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