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

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ISSN: 2056-9890

Di­methyl 2,6-di­methyl-4-(2-nitro­phen­yl)pyridine-3,5-di­carboxyl­ate

aDepartment of Chemistry, School of Science, Tianjin University, Tianjin 300072, People's Republic of China, bTianJin Centralpharm Limited Company, Tianjin 300072, People's Republic of China, and cHigh Pressure Adsorption Laboratory, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
*Correspondence e-mail: suweihb@tju.edu.cn

(Received 21 September 2011; accepted 27 September 2011; online 5 October 2011)

The title compound, C17H16N2O6, is a decomposition product of the hypertension drug nifedipine [systematic name: dimethyl 2,6-dimethyl-4-(2-nitro­phen­yl)-1,4-dihydro­pyridine-3,5-dicarboxyl­ate]. The dihedral angle between the nitro­sophenyl ring and the pyridine ring is 67.1 (5)°.

Related literature

For the calcium antagonistic activity of compounds of the 1,4-dihydro­pyridine class, which inhibit the influx of Ca2+ ions through plasma membrane channels, see: Núnez-Vergara et al. (1994[Núnez-Vergara, L. J., Sunkel, C. & Squella, J. A. (1994). J. Pharm. Sci. 83, 502-507.]) and for their current use in the treatment of a variety of cardiovascular disorders such as angina and hypertension, see: Triggle et al. (1989[Triggle, D. J., Langs, D. A. & Janis, R. A. (1989). Med. Res. Rev. 9, 123-180.]); Hurwitz et al. (1991[Hurwitz, L., Partridge, L. D. & Leach, J. K. (1991). In Calcium Channels: Their Properties, Functions, Regulation and Clinical Relevance. Boca Raton, Florida, USA: CRC Press.]). For general background to derivatives of the dihydropyridine calcium channel blockers nifedipine [3,5-dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate] and nisoldpine [isobutyl methyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate], see: Chen et al. (2010[Chen, H., Qu, D., Wang, Q.-F. & Jiang, R. (2010). Acta Cryst. E66, o619.]); Rowan & Holt (1996[Rowan, K. R. & Holt, E. M. (1996). Acta Cryst. C52, 1565-1570.], 1997a[Rowan, K. R. & Holt, E. M. (1997a). Acta Cryst. C53, 106-108.],b[Rowan, K. R. & Holt, E. M. (1997b). Acta Cryst. C53, 257-261.]); Schultheiss et al. (2010[Schultheiss, N., Roe, M. & Smit, J. P. (2010). Acta Cryst. E66, o2297-o2298.]). For standard bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C17H16N2O6

  • Mr = 344.32

  • Triclinic, [P \overline 1]

  • a = 7.578 (4) Å

  • b = 8.141 (4) Å

  • c = 14.235 (9) Å

  • α = 103.32 (2)°

  • β = 93.75 (5)°

  • γ = 105.39 (3)°

  • V = 816.4 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 298 K

  • 0.20 × 0.18 × 0.12 mm

Data collection
  • Rigaku Saturn724 CCD diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear and CrystalStructure. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.979, Tmax = 0.987

  • 8658 measured reflections

  • 3843 independent reflections

  • 2247 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.097

  • S = 1.03

  • 3843 reflections

  • 230 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.29 e Å−3

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear and CrystalStructure. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: CrystalStructure (Rigaku, 2005[Rigaku (2005). CrystalClear and CrystalStructure. Rigaku Corporation, Tokyo, Japan.]).

Supporting information


Comment top

Compounds of the 1,4-dihydropyridine class exhibit calcium antagonistic activity, as they inhibit the influx of Ca2+ ions through plasma membrane channels (Núnez-Vergara, Sunkel & Squella, 1994). Compounds of this class are currently being used in the treatment of a variety of cardiovascular disorders, such as angina and hypertension (Triggle et al., 1989; Hurwitz et al., 1991). Nifedipine [dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate], is the best known member of this class. The molecular structure of (I) is shown in Fig. 1. The bond lengths and angles are within normal ranges (Allen et al., 1987). The dihedral angle between the nitrosophenyl ring and the pyridine ring is 67.1°.

Related literature top

For the calcium antagonistic activity of 1,4-dihydropyridines, see: Núnez-Vergara et al. (1994) and for their use in the treatment of a variety of cardiovascular disorders, such as angina and hypertension, see: Triggle et al. (1989); Hurwitz et al. (1991). For standard bond lengths, see: Allen et al. (1987). For related literature, see: Chen et al. (2010); Rowan & Holt (1996, 1997a,b); Schultheiss et al. (2010).

Experimental top

The title compound was prepared by adding following steps. 1: Add 1 g nifedipine and 10 g (NH4)2S2O8 to the 100 ml acetone solution(50%). 2: Stir for 12 h at 30 °C.3:Regulate the solution to pH=8 with Na2CO3. The resulting solution was extracted with methylene chloride. The organic layer was dried over MgSO4 and evaporated under reduced pressure. Following washing the extract with water, crystals of suitable size for single-crystal analysis were recrystallized from methanol.

Refinement top

H atoms were positioned geometrically, with C—H = 0.93 and 0.96 A ° for aromatic and methyl H atoms, respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.2 for aromatic and x = 1.5 for methyl H atoms.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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: CrystalStructure (Rigaku, 2005).

Figures top
[Figure 1] Fig. 1. [3,5-dimethyl 2,6-dimethyl-4-(2-nitrophenyl)pyridine-3,5-dicarboxylate]
Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)pyridine-3,5-dicarboxylate top
Crystal data top
C17H16N2O6Z = 2
Mr = 344.32F(000) = 360
Triclinic, P1Dx = 1.401 Mg m3
a = 7.578 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 8.141 (4) ÅCell parameters from 2919 reflections
c = 14.235 (9) Åθ = 1.5–28.0°
α = 103.32 (2)°µ = 0.11 mm1
β = 93.75 (5)°T = 298 K
γ = 105.39 (3)°Prism, yellow
V = 816.4 (8) Å30.20 × 0.18 × 0.12 mm
Data collection top
Rigaku Saturn724 CCD
diffractometer
3843 independent reflections
Radiation source: rotating anode2247 reflections with I > 2σ(I)
Multilayer monochromatorRint = 0.047
Detector resolution: 14.22 pixels mm-1θmax = 27.9°, θmin = 1.5°
ω and ϕ scansh = 99
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1010
Tmin = 0.979, Tmax = 0.987l = 1817
8658 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.097H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.028P)2]
where P = (Fo2 + 2Fc2)/3
3843 reflections(Δ/σ)max = 0.001
230 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C17H16N2O6γ = 105.39 (3)°
Mr = 344.32V = 816.4 (8) Å3
Triclinic, P1Z = 2
a = 7.578 (4) ÅMo Kα radiation
b = 8.141 (4) ŵ = 0.11 mm1
c = 14.235 (9) ÅT = 298 K
α = 103.32 (2)°0.20 × 0.18 × 0.12 mm
β = 93.75 (5)°
Data collection top
Rigaku Saturn724 CCD
diffractometer
3843 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
2247 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.987Rint = 0.047
8658 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.097H-atom parameters constrained
S = 1.03Δρmax = 0.21 e Å3
3843 reflectionsΔρmin = 0.29 e Å3
230 parameters
Special details top

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) top
xyzUiso*/Ueq
O10.76803 (15)0.93198 (15)0.92024 (8)0.0333 (3)
O20.84798 (13)0.68996 (14)0.85050 (7)0.0240 (3)
O30.40716 (15)0.78829 (15)0.70787 (8)0.0344 (3)
O40.63979 (19)0.91761 (16)0.64507 (10)0.0520 (4)
O50.13443 (14)0.30250 (15)0.61801 (7)0.0279 (3)
O60.18628 (14)0.11367 (14)0.70271 (7)0.0259 (3)
N10.26875 (17)0.55143 (17)0.95102 (9)0.0218 (3)
N20.54570 (19)0.78817 (18)0.66853 (9)0.0283 (3)
C10.5124 (2)0.7905 (2)1.05399 (10)0.0256 (4)
H1A0.47990.89961.05490.038*
H1B0.64710.81651.06510.038*
H1C0.45820.74011.10540.038*
C20.4386 (2)0.6606 (2)0.95644 (10)0.0200 (3)
C30.53855 (19)0.65051 (19)0.87679 (10)0.0184 (3)
C40.45649 (19)0.52477 (19)0.78913 (10)0.0175 (3)
C50.2806 (2)0.4125 (2)0.78490 (10)0.0188 (3)
C60.1892 (2)0.4295 (2)0.86757 (11)0.0200 (3)
C70.0011 (2)0.3140 (2)0.86810 (11)0.0278 (4)
H7A0.00770.21600.89540.042*
H7B0.06530.26750.80130.042*
H7C0.07010.38320.90800.042*
C80.7278 (2)0.7743 (2)0.88633 (11)0.0214 (3)
C91.0316 (2)0.8018 (2)0.84997 (12)0.0297 (4)
H9A1.02280.89480.81830.045*
H9B1.10380.73100.81410.045*
H9C1.09250.85540.91710.045*
C100.55534 (18)0.50220 (19)0.70104 (10)0.0176 (3)
C110.6085 (2)0.3487 (2)0.67264 (10)0.0226 (4)
H110.57740.26120.70770.027*
C120.7059 (2)0.3213 (2)0.59432 (11)0.0267 (4)
H120.74010.21540.57590.032*
C130.7538 (2)0.4482 (2)0.54255 (11)0.0263 (4)
H130.82180.42960.48930.032*
C140.7024 (2)0.6014 (2)0.56854 (11)0.0237 (4)
H140.73420.68870.53340.028*
C150.60384 (19)0.6254 (2)0.64663 (10)0.0202 (3)
C160.19127 (19)0.2747 (2)0.69257 (11)0.0200 (3)
C170.1122 (2)0.0294 (2)0.61593 (12)0.0364 (4)
H17A0.01390.03180.59370.055*
H17B0.11050.14150.63070.055*
H17C0.18980.01160.56460.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0287 (7)0.0182 (6)0.0483 (8)0.0042 (5)0.0079 (5)0.0014 (6)
O20.0200 (6)0.0216 (6)0.0293 (6)0.0058 (5)0.0056 (5)0.0041 (5)
O30.0382 (7)0.0388 (8)0.0381 (7)0.0221 (6)0.0167 (6)0.0170 (6)
O40.0680 (10)0.0273 (8)0.0727 (10)0.0148 (7)0.0355 (8)0.0278 (8)
O50.0279 (6)0.0343 (7)0.0211 (6)0.0059 (5)0.0023 (5)0.0102 (5)
O60.0320 (6)0.0194 (6)0.0223 (6)0.0061 (5)0.0008 (5)0.0004 (5)
N10.0245 (7)0.0220 (7)0.0214 (7)0.0086 (6)0.0074 (5)0.0072 (6)
N20.0376 (9)0.0251 (8)0.0255 (8)0.0098 (7)0.0069 (6)0.0111 (7)
C10.0318 (9)0.0260 (9)0.0212 (8)0.0119 (8)0.0040 (7)0.0058 (7)
C20.0248 (8)0.0195 (8)0.0188 (8)0.0109 (7)0.0036 (6)0.0057 (7)
C30.0200 (8)0.0168 (8)0.0211 (8)0.0080 (7)0.0040 (6)0.0065 (7)
C40.0205 (8)0.0173 (8)0.0188 (8)0.0094 (7)0.0062 (6)0.0072 (7)
C50.0210 (8)0.0190 (8)0.0188 (8)0.0077 (7)0.0052 (6)0.0066 (7)
C60.0222 (8)0.0190 (8)0.0217 (8)0.0082 (7)0.0065 (6)0.0072 (7)
C70.0247 (9)0.0281 (10)0.0287 (9)0.0048 (8)0.0119 (7)0.0045 (8)
C80.0248 (8)0.0223 (9)0.0176 (8)0.0074 (7)0.0039 (6)0.0051 (7)
C90.0192 (8)0.0312 (10)0.0363 (10)0.0029 (7)0.0059 (7)0.0085 (8)
C100.0131 (7)0.0195 (8)0.0170 (8)0.0008 (6)0.0016 (6)0.0034 (6)
C110.0219 (8)0.0213 (9)0.0241 (9)0.0054 (7)0.0041 (7)0.0055 (7)
C120.0244 (9)0.0258 (9)0.0285 (9)0.0101 (8)0.0054 (7)0.0005 (8)
C130.0201 (8)0.0334 (10)0.0210 (9)0.0047 (8)0.0067 (6)0.0012 (8)
C140.0207 (8)0.0276 (9)0.0194 (8)0.0001 (7)0.0039 (6)0.0071 (7)
C150.0185 (8)0.0193 (8)0.0207 (8)0.0034 (7)0.0023 (6)0.0036 (7)
C160.0142 (7)0.0234 (9)0.0231 (9)0.0041 (7)0.0080 (6)0.0073 (7)
C170.0424 (11)0.0262 (10)0.0303 (10)0.0072 (9)0.0033 (8)0.0074 (8)
Geometric parameters (Å, º) top
O1—C81.2086 (18)C5—C161.498 (2)
O2—C81.3392 (18)C6—C71.500 (2)
O2—C91.4485 (18)C7—H7A0.9800
O3—N21.2218 (16)C7—H7B0.9800
O4—N21.2349 (16)C7—H7C0.9800
O5—C161.2107 (18)C9—H9A0.9800
O6—C161.3427 (19)C9—H9B0.9800
O6—C171.4481 (19)C9—H9C0.9800
N1—C21.342 (2)C10—C151.393 (2)
N1—C61.344 (2)C10—C111.394 (2)
N2—C151.478 (2)C11—C121.385 (2)
C1—C21.506 (2)C11—H110.9500
C1—H1A0.9800C12—C131.388 (2)
C1—H1B0.9800C12—H120.9500
C1—H1C0.9800C13—C141.381 (2)
C2—C31.403 (2)C13—H130.9500
C3—C41.401 (2)C14—C151.385 (2)
C3—C81.495 (2)C14—H140.9500
C4—C51.390 (2)C17—H17A0.9800
C4—C101.502 (2)C17—H17B0.9800
C5—C61.402 (2)C17—H17C0.9800
C8—O2—C9115.40 (13)O2—C8—C3111.74 (14)
C16—O6—C17115.28 (12)O2—C9—H9A109.5
C2—N1—C6120.11 (13)O2—C9—H9B109.5
O3—N2—O4123.19 (15)H9A—C9—H9B109.5
O3—N2—C15118.96 (13)O2—C9—H9C109.5
O4—N2—C15117.85 (14)H9A—C9—H9C109.5
C2—C1—H1A109.5H9B—C9—H9C109.5
C2—C1—H1B109.5C15—C10—C11116.86 (13)
H1A—C1—H1B109.5C15—C10—C4125.17 (14)
C2—C1—H1C109.5C11—C10—C4117.94 (13)
H1A—C1—H1C109.5C12—C11—C10121.28 (15)
H1B—C1—H1C109.5C12—C11—H11119.4
N1—C2—C3121.69 (15)C10—C11—H11119.4
N1—C2—C1114.91 (13)C11—C12—C13120.22 (15)
C3—C2—C1123.39 (14)C11—C12—H12119.9
C4—C3—C2118.72 (14)C13—C12—H12119.9
C4—C3—C8121.45 (13)C14—C13—C12119.93 (14)
C2—C3—C8119.83 (14)C14—C13—H13120.0
C5—C4—C3118.81 (13)C12—C13—H13120.0
C5—C4—C10118.94 (14)C13—C14—C15118.90 (15)
C3—C4—C10122.20 (13)C13—C14—H14120.5
C4—C5—C6119.36 (14)C15—C14—H14120.5
C4—C5—C16119.84 (13)C14—C15—C10122.80 (15)
C6—C5—C16120.80 (14)C14—C15—N2116.56 (14)
N1—C6—C5121.30 (14)C10—C15—N2120.61 (13)
N1—C6—C7116.40 (13)O5—C16—O6123.94 (15)
C5—C6—C7122.30 (14)O5—C16—C5125.59 (15)
C6—C7—H7A109.5O6—C16—C5110.45 (13)
C6—C7—H7B109.5O6—C17—H17A109.5
H7A—C7—H7B109.5O6—C17—H17B109.5
C6—C7—H7C109.5H17A—C17—H17B109.5
H7A—C7—H7C109.5O6—C17—H17C109.5
H7B—C7—H7C109.5H17A—C17—H17C109.5
O1—C8—O2123.61 (15)H17B—C17—H17C109.5
O1—C8—C3124.63 (14)
C6—N1—C2—C30.6 (2)C5—C4—C10—C15115.28 (17)
C6—N1—C2—C1179.75 (12)C3—C4—C10—C1567.4 (2)
N1—C2—C3—C41.1 (2)C5—C4—C10—C1166.86 (18)
C1—C2—C3—C4179.85 (13)C3—C4—C10—C11110.45 (17)
N1—C2—C3—C8179.70 (13)C15—C10—C11—C120.4 (2)
C1—C2—C3—C80.7 (2)C4—C10—C11—C12177.67 (14)
C2—C3—C4—C51.2 (2)C10—C11—C12—C130.4 (2)
C8—C3—C4—C5179.60 (13)C11—C12—C13—C140.7 (2)
C2—C3—C4—C10178.56 (13)C12—C13—C14—C150.2 (2)
C8—C3—C4—C102.3 (2)C13—C14—C15—C100.6 (2)
C3—C4—C5—C60.9 (2)C13—C14—C15—N2177.47 (13)
C10—C4—C5—C6178.33 (13)C11—C10—C15—C140.9 (2)
C3—C4—C5—C16178.88 (13)C4—C10—C15—C14176.99 (14)
C10—C4—C5—C161.5 (2)C11—C10—C15—N2177.12 (13)
C2—N1—C6—C50.3 (2)C4—C10—C15—N25.0 (2)
C2—N1—C6—C7179.65 (13)O3—N2—C15—C14152.38 (14)
C4—C5—C6—N10.5 (2)O4—N2—C15—C1427.0 (2)
C16—C5—C6—N1179.35 (13)O3—N2—C15—C1025.7 (2)
C4—C5—C6—C7179.50 (13)O4—N2—C15—C10154.89 (15)
C16—C5—C6—C70.7 (2)C17—O6—C16—O51.9 (2)
C9—O2—C8—O13.1 (2)C17—O6—C16—C5176.59 (11)
C9—O2—C8—C3175.45 (12)C4—C5—C16—O570.6 (2)
C4—C3—C8—O1131.12 (17)C6—C5—C16—O5109.63 (18)
C2—C3—C8—O148.0 (2)C4—C5—C16—O6107.95 (15)
C4—C3—C8—O247.44 (18)C6—C5—C16—O671.86 (17)
C2—C3—C8—O2133.40 (14)

Experimental details

Crystal data
Chemical formulaC17H16N2O6
Mr344.32
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)7.578 (4), 8.141 (4), 14.235 (9)
α, β, γ (°)103.32 (2), 93.75 (5), 105.39 (3)
V3)816.4 (8)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.20 × 0.18 × 0.12
Data collection
DiffractometerRigaku Saturn724 CCD
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.979, 0.987
No. of measured, independent and
observed [I > 2σ(I)] reflections
8658, 3843, 2247
Rint0.047
(sin θ/λ)max1)0.659
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.097, 1.03
No. of reflections3843
No. of parameters230
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.29

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), CrystalStructure (Rigaku, 2005).

 

Acknowledgements

This study was supported by the Tianjin Natural Science Foundation (10JCZDJC23900).

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