organic compounds
1-Methyl-1,2,3,4-tetrahydrocarbolin-2-ium-3-carboxylate
aDepartment of Chemistry, School of Pharmacy, Fourth Military Medical University, Changle West Road 17, 710032 Xi-An, People's Republic of China, and bDepartment of Pharmacy, Xijing Hospital, School of Pharmacy, Fourth Military Medical University, Changle West Road 17, 710032 Xi-An, People's Republic of China
*Correspondence e-mail: tanghaifeng71@163.com, xiaoli_sun@yahoo.cn
The title compound, C13H14N2O2, is a natural product isolated from Cicer arietinum L. (chickpea). The benzene ring and pyrrole rings display planar conformations and the piperidine ring has a half-chair conformation. Intermolecular C—H⋯π interactions between a methyl H atom and the pyrrole ring of an adjacent molecule are present in the crystal structure.
Related literature
For the isolation of the title compound as a natural product, see: Kicha et al. (2003). For the bioactivity of the title compound, see: Adachi et al. (1991); Ogawa & Adachi (1993).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2000); cell SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536810002163/pb2017sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810002163/pb2017Isup2.hkl
6 kg of the dried chickpea seeds were crushed and refluxed with 70% ethanol. After condensation in a rotary evaporator, 0.6 L of a syrupy residue was obtained. The residue was suspended in water and extracted by successive partitioning with petroleum ether, EtOAc, and n-butanol saturated with H2O, respectively. The n-butanol portion (60 g) was fractionated over silica gel column eluted with a continuous gradient of CHCl3/MeOH/H2O (15:1:0–6:4:0.8) mixtures of increasing polarity. Fraction eluted with CHCl3/MeOH/H2O (7:3:0.5) was combined and afforded crude title compound (1.13 g). Suitable crystal for determining the X-ray stucture was obtained with a further purification by re-crystallization in MeOH/H2O (1:1). [α] D= 86° (MeOH, 1/4). Spectroscopic analysis: 1H NMR(CD3OD, 500 MHz): δH 4.71 (1H, q, J=7 Hz), 3.96 (1H, dd, J=12, 5.0 Hz), 3.03 (1H, m), 3.45 (1H, m), 7.47 (1H, d, J=8.0 Hz), 7.05 (1H, m), 7.13 (1H, m), 7.34 (1H, d, J=8.0 Hz), 1.75 (3H, d, J=7.0 Hz); 13C NMR (CD3OD, 125 MHz): δc 51.2 (C-10), 59.8 (C-9), 24.3 (C-8), 107.8 (C-7), 127.5 (C-6), 119.2 (C-5), 120.6 (C-4), 123.3 (C-3), 112.3 (C-2), 138.6 (C-1), 131.3 (C-11), 17.1 (C-12), 173.6(C-13).
All H atoms were positioned geometrically and treated as riding with aromatic C—H = 0.93 Å, methine C—H = 0.98 Å, methylene C—H = 0.97Å & methyl C—H = 0.96 Å. The H atom isotropic displacement parameters were fixed; Uiso(aromatic H, methine H) = 1.2 times Ueq of the parent atom; Uiso(methylene H, methyl H) = 1.5 times Ueq of the parent atom. Friedel pairs were merged.
The title compound is isolated from Cicer arietinum L. (Chickpea), It is a precursor of mutagenic N-nitroso compounds, which show direct-acting mutagenicity on Salmonlla typhimurium TA 100 (Adachi et al., 1991) and may cause eosinophilia-myalgia syndrome (EMS) associated with ingestion of L-tryptophan (Ogawa, 1993).
The benzene ring and pyrrole ring display a planar conformation, and the piperidine ring has a half chair conformation. The molecular packing is stabilized by an intermolecular C–H···π interactions between methyl H atom of piperidine ring pyrrole ring of an adjacent molecule, with a C10–H10···Cg1 separation of 2.69 Å (Table 1, Cg1 is the centroid of C1—C6—C7—C11—N1 pyrrole ring).
For the isolation of the title compound as a natural product, see: Kicha et al. (2003). For the bioactivity of the title compound, see: Adachi et al. (1991); Ogawa et al. (1993).
Data collection: APEX2 (Bruker, 2000); cell
SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).C13H14N2O2 | F(000) = 488 |
Mr = 230.26 | Dx = 1.383 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 666 reflections |
a = 4.9772 (8) Å | θ = 2.7–18.0° |
b = 14.520 (2) Å | µ = 0.10 mm−1 |
c = 15.307 (2) Å | T = 296 K |
V = 1106.3 (3) Å3 | Needle, colorless |
Z = 4 | 0.32 × 0.23 × 0.13 mm |
Bruker APEXII CCD area-detector diffractometer | 1166 independent reflections |
Radiation source: fine-focus sealed tube | 880 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.053 |
phi and ω scans | θmax = 25.1°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −5→5 |
Tmin = 0.971, Tmax = 0.988 | k = −17→15 |
5528 measured reflections | l = −16→18 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.042 | H-atom parameters constrained |
wR(F2) = 0.117 | w = 1/[σ2(Fo2) + (0.074P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max < 0.001 |
1166 reflections | Δρmax = 0.22 e Å−3 |
156 parameters | Δρmin = −0.17 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.026 (6) |
C13H14N2O2 | V = 1106.3 (3) Å3 |
Mr = 230.26 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 4.9772 (8) Å | µ = 0.10 mm−1 |
b = 14.520 (2) Å | T = 296 K |
c = 15.307 (2) Å | 0.32 × 0.23 × 0.13 mm |
Bruker APEXII CCD area-detector diffractometer | 1166 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2000) | 880 reflections with I > 2σ(I) |
Tmin = 0.971, Tmax = 0.988 | Rint = 0.053 |
5528 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.117 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.22 e Å−3 |
1166 reflections | Δρmin = −0.17 e Å−3 |
156 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 | 0.3184 (7) | 0.56276 (18) | 0.71317 (15) | 0.0402 (7) | |
H1 | 0.2878 | 0.5045 | 0.7104 | 0.048* | |
N2 | −0.0123 (6) | 0.67564 (14) | 0.90152 (14) | 0.0319 (6) | |
H2A | −0.1486 | 0.6668 | 0.9393 | 0.038* | |
H2B | 0.1421 | 0.6729 | 0.9320 | 0.038* | |
O2 | −0.0135 (5) | 0.82385 (13) | 1.00915 (13) | 0.0390 (6) | |
O1 | −0.2002 (7) | 0.91384 (15) | 0.90704 (15) | 0.0581 (8) | |
C1 | 0.4997 (7) | 0.6110 (2) | 0.66226 (19) | 0.0382 (8) | |
C2 | 0.6786 (8) | 0.5800 (3) | 0.59940 (19) | 0.0476 (9) | |
H2 | 0.6826 | 0.5183 | 0.5830 | 0.057* | |
C3 | 0.8495 (8) | 0.6429 (3) | 0.5621 (2) | 0.0539 (11) | |
H3 | 0.9745 | 0.6232 | 0.5209 | 0.065* | |
C4 | 0.8388 (8) | 0.7364 (3) | 0.5849 (2) | 0.0503 (9) | |
H4 | 0.9523 | 0.7782 | 0.5574 | 0.060* | |
C5 | 0.6633 (8) | 0.7669 (3) | 0.6473 (2) | 0.0441 (9) | |
H5 | 0.6573 | 0.8290 | 0.6622 | 0.053* | |
C6 | 0.4939 (7) | 0.7043 (2) | 0.68836 (19) | 0.0348 (7) | |
C7 | 0.2982 (7) | 0.7105 (2) | 0.75634 (17) | 0.0343 (8) | |
C8 | 0.2132 (7) | 0.7924 (2) | 0.8087 (2) | 0.0369 (8) | |
H8A | 0.1759 | 0.8437 | 0.7699 | 0.044* | |
H8B | 0.3574 | 0.8105 | 0.8477 | 0.044* | |
C9 | −0.0383 (7) | 0.7696 (2) | 0.86201 (19) | 0.0325 (8) | |
H9 | −0.1924 | 0.7690 | 0.8222 | 0.039* | |
C10 | −0.0145 (7) | 0.59951 (19) | 0.83517 (18) | 0.0345 (8) | |
H10 | −0.1902 | 0.5989 | 0.8062 | 0.041* | |
C11 | 0.1945 (8) | 0.6245 (2) | 0.76945 (19) | 0.0348 (8) | |
C12 | 0.0263 (10) | 0.5078 (2) | 0.8807 (2) | 0.0550 (11) | |
H12A | 0.1971 | 0.5078 | 0.9098 | 0.082* | |
H12B | 0.0219 | 0.4591 | 0.8383 | 0.082* | |
H12C | −0.1142 | 0.4986 | 0.9228 | 0.082* | |
C13 | −0.0897 (7) | 0.8423 (2) | 0.9318 (2) | 0.0355 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0454 (19) | 0.0379 (14) | 0.0374 (15) | −0.0017 (15) | 0.0046 (15) | −0.0056 (11) |
N2 | 0.0258 (15) | 0.0372 (13) | 0.0326 (13) | −0.0020 (13) | −0.0009 (14) | −0.0002 (10) |
O2 | 0.0340 (14) | 0.0448 (13) | 0.0381 (12) | 0.0015 (11) | 0.0012 (12) | −0.0039 (10) |
O1 | 0.076 (2) | 0.0457 (14) | 0.0523 (14) | 0.0215 (15) | 0.0009 (15) | 0.0018 (12) |
C1 | 0.035 (2) | 0.0501 (19) | 0.0292 (16) | 0.0034 (19) | −0.0021 (17) | −0.0026 (13) |
C2 | 0.048 (2) | 0.061 (2) | 0.0336 (17) | 0.011 (2) | 0.0031 (19) | −0.0081 (17) |
C3 | 0.038 (2) | 0.087 (3) | 0.037 (2) | 0.005 (2) | 0.0069 (19) | −0.0038 (19) |
C4 | 0.034 (2) | 0.079 (3) | 0.0377 (18) | −0.009 (2) | 0.0057 (19) | 0.0038 (18) |
C5 | 0.038 (2) | 0.056 (2) | 0.0382 (17) | −0.0014 (19) | 0.0014 (18) | 0.0012 (15) |
C6 | 0.0291 (18) | 0.0470 (18) | 0.0283 (14) | 0.0000 (17) | −0.0003 (16) | −0.0008 (13) |
C7 | 0.032 (2) | 0.0406 (17) | 0.0303 (16) | −0.0006 (15) | −0.0002 (16) | −0.0013 (12) |
C8 | 0.033 (2) | 0.0390 (17) | 0.0383 (16) | −0.0018 (15) | 0.0021 (16) | 0.0035 (13) |
C9 | 0.026 (2) | 0.0388 (17) | 0.0324 (15) | 0.0009 (14) | 0.0005 (15) | 0.0017 (13) |
C10 | 0.0354 (19) | 0.0374 (17) | 0.0306 (16) | −0.0050 (17) | 0.0013 (17) | −0.0018 (12) |
C11 | 0.0312 (19) | 0.0412 (18) | 0.0319 (15) | 0.0003 (15) | −0.0038 (15) | −0.0034 (13) |
C12 | 0.073 (3) | 0.041 (2) | 0.051 (2) | −0.001 (2) | 0.009 (2) | 0.0002 (15) |
C13 | 0.0307 (19) | 0.0395 (18) | 0.0363 (18) | −0.0005 (15) | 0.0043 (15) | 0.0011 (14) |
N1—C1 | 1.383 (4) | C5—C6 | 1.390 (5) |
N1—C11 | 1.388 (4) | C5—H5 | 0.9300 |
N1—H1 | 0.8600 | C6—C7 | 1.428 (5) |
N2—C9 | 1.498 (4) | C7—C11 | 1.367 (4) |
N2—C10 | 1.501 (3) | C7—C8 | 1.495 (4) |
N2—H2A | 0.9000 | C8—C9 | 1.530 (5) |
N2—H2B | 0.9000 | C8—H8A | 0.9700 |
O2—C13 | 1.272 (4) | C8—H8B | 0.9700 |
O1—C13 | 1.234 (4) | C9—C13 | 1.523 (4) |
C1—C2 | 1.386 (5) | C9—H9 | 0.9800 |
C1—C6 | 1.412 (4) | C10—C11 | 1.492 (4) |
C2—C3 | 1.373 (5) | C10—C12 | 1.516 (4) |
C2—H2 | 0.9300 | C10—H10 | 0.9800 |
C3—C4 | 1.404 (5) | C12—H12A | 0.9600 |
C3—H3 | 0.9300 | C12—H12B | 0.9600 |
C4—C5 | 1.368 (5) | C12—H12C | 0.9600 |
C4—H4 | 0.9300 | ||
C1—N1—C11 | 108.2 (3) | C7—C8—C9 | 110.2 (3) |
C1—N1—H1 | 125.9 | C7—C8—H8A | 109.6 |
C11—N1—H1 | 125.9 | C9—C8—H8A | 109.6 |
C9—N2—C10 | 113.4 (2) | C7—C8—H8B | 109.6 |
C9—N2—H2A | 108.9 | C9—C8—H8B | 109.6 |
C10—N2—H2A | 108.9 | H8A—C8—H8B | 108.1 |
C9—N2—H2B | 108.9 | N2—C9—C13 | 111.3 (2) |
C10—N2—H2B | 108.9 | N2—C9—C8 | 110.0 (3) |
H2A—N2—H2B | 107.7 | C13—C9—C8 | 111.2 (3) |
N1—C1—C2 | 130.2 (3) | N2—C9—H9 | 108.1 |
N1—C1—C6 | 108.2 (3) | C13—C9—H9 | 108.1 |
C2—C1—C6 | 121.4 (3) | C8—C9—H9 | 108.1 |
C3—C2—C1 | 118.1 (3) | C11—C10—N2 | 105.8 (2) |
C3—C2—H2 | 121.0 | C11—C10—C12 | 115.5 (3) |
C1—C2—H2 | 121.0 | N2—C10—C12 | 109.5 (2) |
C2—C3—C4 | 121.1 (3) | C11—C10—H10 | 108.6 |
C2—C3—H3 | 119.5 | N2—C10—H10 | 108.6 |
C4—C3—H3 | 119.5 | C12—C10—H10 | 108.6 |
C5—C4—C3 | 120.8 (4) | C7—C11—N1 | 109.4 (3) |
C5—C4—H4 | 119.6 | C7—C11—C10 | 125.8 (3) |
C3—C4—H4 | 119.6 | N1—C11—C10 | 124.9 (3) |
C4—C5—C6 | 119.4 (3) | C10—C12—H12A | 109.5 |
C4—C5—H5 | 120.3 | C10—C12—H12B | 109.5 |
C6—C5—H5 | 120.3 | H12A—C12—H12B | 109.5 |
C5—C6—C1 | 119.1 (3) | C10—C12—H12C | 109.5 |
C5—C6—C7 | 134.5 (3) | H12A—C12—H12C | 109.5 |
C1—C6—C7 | 106.3 (3) | H12B—C12—H12C | 109.5 |
C11—C7—C6 | 107.8 (3) | O1—C13—O2 | 126.5 (3) |
C11—C7—C8 | 122.8 (3) | O1—C13—C9 | 116.3 (3) |
C6—C7—C8 | 129.4 (3) | O2—C13—C9 | 117.2 (3) |
C11—N1—C1—C2 | 177.1 (3) | C10—N2—C9—C8 | −67.4 (3) |
C11—N1—C1—C6 | 1.3 (4) | C7—C8—C9—N2 | 42.5 (3) |
N1—C1—C2—C3 | −176.0 (3) | C7—C8—C9—C13 | 166.2 (3) |
C6—C1—C2—C3 | −0.7 (5) | C9—N2—C10—C11 | 52.2 (3) |
C1—C2—C3—C4 | −1.8 (5) | C9—N2—C10—C12 | 177.2 (3) |
C2—C3—C4—C5 | 2.2 (6) | C6—C7—C11—N1 | 0.7 (4) |
C3—C4—C5—C6 | 0.0 (6) | C8—C7—C11—N1 | −178.1 (3) |
C4—C5—C6—C1 | −2.4 (5) | C6—C7—C11—C10 | 179.4 (3) |
C4—C5—C6—C7 | 177.5 (4) | C8—C7—C11—C10 | 0.6 (5) |
N1—C1—C6—C5 | 179.0 (3) | C1—N1—C11—C7 | −1.3 (4) |
C2—C1—C6—C5 | 2.8 (5) | C1—N1—C11—C10 | −180.0 (3) |
N1—C1—C6—C7 | −0.9 (3) | N2—C10—C11—C7 | −19.6 (4) |
C2—C1—C6—C7 | −177.1 (3) | C12—C10—C11—C7 | −140.9 (4) |
C5—C6—C7—C11 | −179.8 (4) | N2—C10—C11—N1 | 158.9 (3) |
C1—C6—C7—C11 | 0.1 (4) | C12—C10—C11—N1 | 37.6 (4) |
C5—C6—C7—C8 | −1.1 (6) | N2—C9—C13—O1 | −156.8 (3) |
C1—C6—C7—C8 | 178.8 (3) | C8—C9—C13—O1 | 80.3 (4) |
C11—C7—C8—C9 | −12.0 (4) | N2—C9—C13—O2 | 23.7 (4) |
C6—C7—C8—C9 | 169.5 (3) | C8—C9—C13—O2 | −99.2 (3) |
C10—N2—C9—C13 | 168.9 (3) |
Cg1 is the centroid of C1/C6/C7/C11/N1 pyrrole ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10···Cg1i | 0.98 | 2.69 | 3.644 (3) | 165 |
Symmetry code: (i) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C13H14N2O2 |
Mr | 230.26 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 296 |
a, b, c (Å) | 4.9772 (8), 14.520 (2), 15.307 (2) |
V (Å3) | 1106.3 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.32 × 0.23 × 0.13 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2000) |
Tmin, Tmax | 0.971, 0.988 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5528, 1166, 880 |
Rint | 0.053 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.117, 1.00 |
No. of reflections | 1166 |
No. of parameters | 156 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.17 |
Computer programs: APEX2 (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and ORTEP-3 for Windows (Farrugia, 1997), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
Cg1 is the centroid of C1/C6/C7/C11/N1 pyrrole ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C10—H10···Cg1i | 0.98 | 2.69 | 3.644 (3) | 165 |
Symmetry code: (i) x+1, y, z. |
Acknowledgements
We thank the Natural Science Foundation of China (grant No. 20802092) for financial support.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound is isolated from Cicer arietinum L. (Chickpea), It is a precursor of mutagenic N-nitroso compounds, which show direct-acting mutagenicity on Salmonlla typhimurium TA 100 (Adachi et al., 1991) and may cause eosinophilia-myalgia syndrome (EMS) associated with ingestion of L-tryptophan (Ogawa, 1993).
The benzene ring and pyrrole ring display a planar conformation, and the piperidine ring has a half chair conformation. The molecular packing is stabilized by an intermolecular C–H···π interactions between methyl H atom of piperidine ring pyrrole ring of an adjacent molecule, with a C10–H10···Cg1 separation of 2.69 Å (Table 1, Cg1 is the centroid of C1—C6—C7—C11—N1 pyrrole ring).