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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3096
doi:10.1107/S1600536811043868

Gallic acid pyridine monosolvate

Fu-Yue Dong,a Jie Wu,a Hai-Yan Tian,a Qing-Mei Yea and Ren-Wang Jianga*

aGuangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research, Institute of Traditional Chinese Medicine and Natural Products, Jinan University, Guangzhou 510632, People's Republic of China
*Correspondence e-mail: trwjiang@jnu.edu.cn

(Received 1 October 2011; accepted 22 October 2011; online 29 October 2011)

In the title compound (systenatic name: 3,4,5-trihy­droxy­benzoic acid pyridine monosolvate), C5H5N·C7H6O5, the gallic acid mol­ecule is essentially planar (r.m.s deviation = 0.0766 Å for non-H atoms) and is linked to the pyridine mol­ecule by an O—H⋯N hydrogen bond. An intra­molecular O—H⋯O hydrogen bond occurs in the gallic acid mol­ecule. The gallic acid and pyridine mean planes make a dihedral angle 12.6 (3)°. Inter­molecular O—H⋯O and O—H⋯N hydrogen bonding involving the hy­droxy and carboxyl groups and the pyridine mol­ecule, and π–π inter­actions between inversion-related pyridines [centroid–centroid distance = 3.459 (6) Å] and between pyridine and benzene rings [centroid–centroid distance = 3.548 (6) Å], lead to a three-dimensional network in the crystal.

Related literature

For the biological activity of gallic acid, see: Souza et al. (2011[Souza, B. W. S., Cerqueira, M. A., Martins, J. T., Quintas, M. A. C., Ferreira, A. C. S., Teixeira, J. A. & Vicente, A. A. (2011). J. Agric. Food Chem. 59, 5589-5594.]); Ozcelik et al. (2011[Ozcelik, B., Kartal, M. & Orhan, I. (2011). Pharm. Biol. 49, 396-402.]); Liu et al. (2011[Liu, K. C., Huang, A. C., Wu, P. P., Lin, H. Y., Chueh, F. S., Yang, J. S., Lu, C. C., Chiang, J. H., Meng, M. & Chung, J. G. (2011). Oncol. Rep. 26, 177-184.]). For previous reports on the crystal structures of gallic acid monohydrate and gallic acid monopyridine solvate, see: Clarke et al. (2011[Clarke, H. D., Arora, K. K., Wojtas, L. & Zaworotko, M. J. (2011). Cryst. Growth Des. 11, 964-966.]); Jiang et al. (2000[Jiang, R.-W., Ming, D.-S., But, P. P. H. & Mak, T. C. W. (2000). Acta Cryst. C56, 594-595.]). For π–π inter­actions in natural flavonoids, see: Jiang et al. (2002[Jiang, R. W., Ye, W. C., Woo, K. Y., Du, J., Che, C. T., But, P. P. H. & Mak, T. C. W. (2002). J. Mol. Struct. 642, 77-84.], 2009[Jiang, R. W., Wang, Y., Gao, H., Zhang, D. M. & Ye, W. C. (2009). J. Mol. Struct. 920, 383-386.]).

[Scheme 1]

Experimental

Crystal data

  • C5H5N·C7H6O5

  • Mr = 249.22

  • Monoclinic, P 21 /n

  • a = 9.335 (1) Å

  • b = 10.435 (2) Å

  • c = 11.8581 (15) Å

  • β = 107.632 (8)°

  • V = 1100.9 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 293 K

  • 0.34 × 0.20 × 0.12 mm
Data collection

  • Bruker SMART CCD 1000 diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.821, Tmax = 0.986

  • 2601 measured reflections

  • 1944 independent reflections

  • 1031 reflections with I > 2σ(I)

  • Rint = 0.057
Refinement

  • R[F2 > 2σ(F2)] = 0.066

  • wR(F2) = 0.172

  • S = 1.02

  • 1944 reflections

  • 166 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1A⋯O2i 0.82 2.12 2.869 (3) 152
O1—H1A⋯O2 0.82 2.34 2.736 (4) 110
O2—H2A⋯O5ii 0.82 1.87 2.675 (4) 166
O3—H3A⋯O4iii 0.82 1.91 2.718 (3) 169
O4—H4A⋯N1 0.82 1.92 2.730 (4) 169
Symmetry codes: (i) -x, -y+1, -z+1; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: XP in SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811043868/pk2351sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811043868/pk2351Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811043868/pk2351Isup3.cml

checkCIF report


Comment top

Gallic acid, a dietary polyphenol, is widely distributed in many edible and medicinal plants. It can exist as a single molecule or as a structural unit of hydrolysable tannins. It has been found to show strong pharmacological activities including antioxidant (Souza, et al. 2011), antiviral (Ozcelik, et al., 2011) and antitumor properties (Liu, et al., 2011). This compound contains two of the most common functional groups in natural products, e.g. carboxylic acid and phenolic groups. Crystal engineering studies have revealed interesting polymorphism. Four polymorphs of the monohydrate of gallic acid with three space groups (P 21/c, P 2/n, and P 1), and an anhydrous form with space group C 2/c have been reported (Clarke et al., 2011). We report herein the pyridine monosolvate of gallic acid.

The gallic acid molecule is essentially planar. The mean deviation of the benzene ring is 0.0030 Å, which is similar to that in gallic acid monohydrate (0.0028 Å), and its dihedral angle with the plane of the carboxyl group is 9.8 (3) °, which is larger than that in gallic acid monohydrate (2.9°) (Jiang, et al., 2000). The gallic acid and pyridine molecules make a dihedral angle of 12.8 (4) °. The bond distances are all normal.

Within the asymmetric unit, the gallic acid molecule and pyridine molecule are linked through hydrogen bond O4–H···N1. Intermolecular O—H···O and O—H···N hydrogen-bonding interactions involving the hydroxyl and carboxylic acid groups and the pyridine molecule (Table 1) form a supramolecular assembly. A short intramolecular C—H···O interaction between the C10 methine and a hydroxyl O acceptor is also present [C10–H···O5, 3.169 (18) Å; <C–H···O, 162.0 (5) °]. It is noteworthy that π-π interactions play an important role in the molecular packing. The gallic acid molecules show π-π interactions with the pyridine molecules [centroid-centroid distance 3.548 (6) Å and displacement angle 12.8 (3) °], and inversion-related pyridine molecules are also linked by π-π interactions [centroid-centroid distance = 3.459 (6) Å]. The centroid-centroid distances observed in gallic acid monopyridine solvate are significantly shorter than those in natural flavonoids (Jiang, et al., 2009 and 2002).

Related literature top

For the biological activity of gallic acid, see: Souza et al. (2011); Ozcelik et al. (2011); Liu et al. (2011). For previous reports on the crystal structure of gallic acid, see: Clarke et al. (2011); Jiang et al. (2000). For π–π interactions in natural flavonoids, see: Jiang et al. (2002, 2009).

Experimental top

The title compound was extracted from the whole plant of Polygonum chinense L. The dried plant material (5 kg) was powdered and extracted with 95% ethanol at room temperature to afford the crude extract, which was suspended in distilled water and partitioned with petroleum ether, ethyl acetate and n-butanol. The n-butanol fraction (100g) was subjected to macroporous resin, reverse phase silica gel chromatography to give compound I (21 mg), which was recrystallized in pyridine to afford the monopyridine solvate of gallic acid.

Refinement top

The C-bound H atoms were positioned geometrically and were included in the refinement in the riding-model approximation, with C—H = 0.96 Å (CH3) and Uiso(H) = 1.5Ueq(C); 0.97 Å (CH2) and Uiso(H) = 1.2Ueq(C); 0.93 Å (aryl H) and Uiso(H)= 1.2Ueq(C); O—H = 0.82 Å and Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. The packing diagram viewed approximately down the c-axis.
3,4,5-trihydroxybenzoic acid pyridine monosolvate top
Crystal data top
C5H5N·C7H6O5F(000) = 520
Mr = 249.22Dx = 1.504 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2601 reflections
a = 9.335 (1) Åθ = 2.5–25.0°
b = 10.435 (2) ŵ = 0.12 mm−1
c = 11.8581 (15) ÅT = 293 K
β = 107.632 (8)°Prism, colorless
V = 1100.9 (3) Å30.34 × 0.20 × 0.12 mm
Z = 4
Data collection top
Bruker SMART CCD 1000
diffractometer		1944 independent reflections
Radiation source: fine-focus sealed tube1031 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.057
ω scanθmax = 25.0°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		h = −1→11
Tmin = 0.821, Tmax = 0.986k = −1→12
2601 measured reflectionsl = −14→13
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.066H-atom parameters constrained
wR(F2) = 0.172 w = 1/[σ2(Fo2) + (0.0724P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
1944 reflectionsΔρmax = 0.36 e Å−3
166 parametersΔρmin = −0.30 e Å−3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.026 (5)
Crystal data top
C5H5N·C7H6O5V = 1100.9 (3) Å3
Mr = 249.22Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.335 (1) ŵ = 0.12 mm−1
b = 10.435 (2) ÅT = 293 K
c = 11.8581 (15) Å0.34 × 0.20 × 0.12 mm
β = 107.632 (8)°
Data collection top
Bruker SMART CCD 1000
diffractometer		1944 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)		1031 reflections with I > 2σ(I)
Tmin = 0.821, Tmax = 0.986Rint = 0.057
2601 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0660 restraints
wR(F2) = 0.172H-atom parameters constrained
S = 1.02Δρmax = 0.36 e Å−3
1944 reflectionsΔρmin = −0.30 e Å−3
166 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
O10.2507 (3)0.4817 (3)0.5719 (2)0.0455 (9)
H1A0.16130.49180.56500.068*
O20.0218 (3)0.5026 (3)0.3644 (3)0.0478 (9)
H2A−0.00030.55590.31110.09 (2)*
O30.0523 (3)0.3953 (3)0.1596 (2)0.0443 (9)
H3A0.07220.35590.10640.026 (12)*
O40.6443 (3)0.2100 (3)0.4836 (2)0.0447 (9)
H4A0.73010.20410.47940.067*
O50.5775 (3)0.1955 (3)0.2878 (2)0.0372 (8)
C10.4139 (4)0.3050 (4)0.3759 (3)0.0272 (10)
C20.3957 (4)0.3632 (4)0.4761 (3)0.0335 (10)
H2B0.47180.35810.54780.040*
C30.2654 (4)0.4285 (4)0.4696 (3)0.0319 (10)
C40.1511 (4)0.4397 (4)0.3634 (3)0.0293 (10)
C50.1690 (4)0.3824 (4)0.2629 (3)0.0299 (10)
C60.2988 (4)0.3151 (4)0.2682 (3)0.0308 (10)
H6A0.30960.27680.20040.037*
C70.5536 (4)0.2314 (4)0.3809 (3)0.0298 (10)
N10.9126 (4)0.1750 (4)0.4402 (4)0.0467 (10)
C81.1809 (5)0.0925 (5)0.4259 (5)0.0508 (13)
H8A1.27310.06300.42160.061*
C91.1691 (5)0.1366 (5)0.5296 (5)0.0544 (14)
H9A1.25320.13870.59620.065*
C101.0337 (6)0.1779 (5)0.5367 (4)0.0516 (14)
H10A1.02510.20820.60820.062*
C110.9235 (6)0.1326 (5)0.3370 (4)0.0529 (14)
H11A0.83890.13120.27080.063*
C121.0599 (6)0.0908 (5)0.3285 (4)0.0542 (14)
H12A1.06850.06190.25670.065*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0410 (17)0.066 (2)0.0299 (16)0.0120 (17)0.0106 (13)−0.0052 (16)
O20.0428 (18)0.065 (2)0.0382 (17)0.0205 (18)0.0164 (14)0.0152 (18)
O30.0319 (16)0.067 (2)0.0288 (16)0.0128 (16)0.0009 (13)−0.0029 (17)
O40.0269 (15)0.071 (2)0.0322 (16)0.0146 (17)0.0036 (13)0.0038 (16)
O50.0367 (16)0.051 (2)0.0277 (15)0.0034 (15)0.0150 (12)−0.0043 (15)
C10.024 (2)0.032 (2)0.026 (2)−0.0016 (19)0.0081 (17)0.0049 (18)
C20.027 (2)0.044 (3)0.024 (2)−0.001 (2)−0.0009 (17)−0.002 (2)
C30.036 (2)0.036 (3)0.026 (2)−0.001 (2)0.0132 (19)−0.0036 (19)
C40.027 (2)0.035 (3)0.026 (2)0.009 (2)0.0088 (17)0.0079 (19)
C50.022 (2)0.038 (3)0.026 (2)−0.003 (2)0.0023 (17)0.0054 (19)
C60.026 (2)0.043 (3)0.0227 (19)−0.005 (2)0.0056 (16)0.0005 (19)
C70.0213 (19)0.039 (3)0.026 (2)−0.005 (2)0.0024 (17)0.003 (2)
N10.036 (2)0.043 (3)0.065 (3)0.0048 (19)0.021 (2)0.005 (2)
C80.042 (3)0.039 (3)0.078 (4)0.006 (2)0.028 (3)0.013 (3)
C90.037 (3)0.054 (3)0.060 (3)−0.008 (3)−0.003 (2)0.011 (3)
C100.067 (3)0.048 (3)0.047 (3)−0.012 (3)0.028 (3)−0.009 (3)
C110.054 (3)0.048 (3)0.043 (3)−0.003 (3)−0.006 (2)0.012 (3)
C120.077 (4)0.049 (3)0.049 (3)0.004 (3)0.038 (3)0.002 (3)
Geometric parameters (Å, º) top
O1—C31.379 (5)C4—C51.388 (5)
O1—H1A0.8200C5—C61.385 (5)
O2—C41.377 (5)C6—H6A0.9300
O2—H2A0.8200N1—C111.333 (6)
O3—C51.378 (4)N1—C101.343 (6)
O3—H3A0.8200C8—C91.348 (7)
O4—C71.275 (4)C8—C121.349 (7)
O4—H4A0.8200C8—H8A0.9300
O5—C71.248 (4)C9—C101.362 (7)
C1—C21.391 (5)C9—H9A0.9300
C1—C61.402 (5)C10—H10A0.9300
C1—C71.499 (5)C11—C121.379 (7)
C2—C31.375 (5)C11—H11A0.9300
C2—H2B0.9300C12—H12A0.9300
C3—C41.387 (5)
C3—O1—H1A109.5C1—C6—H6A120.1
C4—O2—H2A109.5O5—C7—O4123.2 (4)
C5—O3—H3A109.5O5—C7—C1120.3 (3)
C7—O4—H4A109.5O4—C7—C1116.5 (3)
C2—C1—C6119.2 (4)C11—N1—C10120.8 (4)
C2—C1—C7121.3 (3)C9—C8—C12120.4 (5)
C6—C1—C7119.5 (3)C9—C8—H8A119.8
C3—C2—C1120.2 (3)C12—C8—H8A119.8
C3—C2—H2B119.9C8—C9—C10119.9 (5)
C1—C2—H2B119.9C8—C9—H9A120.1
C2—C3—O1118.2 (3)C10—C9—H9A120.1
C2—C3—C4121.1 (4)N1—C10—C9119.8 (4)
O1—C3—C4120.7 (4)N1—C10—H10A120.1
O2—C4—C3117.9 (4)C9—C10—H10A120.1
O2—C4—C5123.1 (3)N1—C11—C12120.0 (5)
C3—C4—C5118.9 (4)N1—C11—H11A120.0
O3—C5—C6122.3 (4)C12—C11—H11A120.0
O3—C5—C4116.9 (4)C8—C12—C11119.1 (5)
C6—C5—C4120.7 (3)C8—C12—H12A120.5
C5—C6—C1119.8 (4)C11—C12—H12A120.5
C5—C6—H6A120.1
C6—C1—C2—C30.9 (6)C4—C5—C6—C1−0.2 (6)
C7—C1—C2—C3−179.0 (4)C2—C1—C6—C5−0.2 (6)
C1—C2—C3—O1178.3 (4)C7—C1—C6—C5179.7 (4)
C1—C2—C3—C4−1.2 (6)C2—C1—C7—O5−169.7 (4)
C2—C3—C4—O2177.8 (4)C6—C1—C7—O510.4 (6)
O1—C3—C4—O2−1.6 (6)C2—C1—C7—O49.5 (6)
C2—C3—C4—C50.8 (6)C6—C1—C7—O4−170.3 (4)
O1—C3—C4—C5−178.7 (4)C12—C8—C9—C101.0 (8)
O2—C4—C5—O32.7 (6)C11—N1—C10—C9−0.4 (7)
C3—C4—C5—O3179.6 (4)C8—C9—C10—N1−0.2 (8)
O2—C4—C5—C6−177.0 (4)C10—N1—C11—C120.2 (7)
C3—C4—C5—C6−0.1 (7)C9—C8—C12—C11−1.2 (8)
O3—C5—C6—C1−179.9 (4)N1—C11—C12—C80.6 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O2i0.822.122.869 (3)152
O1—H1A···O20.822.342.736 (4)110
O2—H2A···O5ii0.821.872.675 (4)166
O3—H3A···O4iii0.821.912.718 (3)169
O4—H4A···N10.821.922.730 (4)169
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1/2, y+1/2, −z+1/2; (iii) x−1/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formulaC5H5N·C7H6O5
Mr249.22
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)9.335 (1), 10.435 (2), 11.8581 (15)
β (°) 107.632 (8)
V (Å3)1100.9 (3)
Z4
Radiation typeMo Kα
µ (mm−1)0.12
Crystal size (mm)0.34 × 0.20 × 0.12
Data collection
DiffractometerBruker SMART CCD 1000
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.821, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections		2601, 1944, 1031
Rint0.057
(sin θ/λ)max (Å−1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.066, 0.172, 1.02
No. of reflections1944
No. of parameters166
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.36, −0.30

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O2i0.8202.1202.869 (3)151.88
O1—H1A···O20.8202.3432.736 (4)110.07
O2—H2A···O5ii0.8201.8722.675 (4)165.87
O3—H3A···O4iii0.8201.9082.718 (3)169.19
O4—H4A···N10.8201.9212.730 (4)168.78
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1/2, y+1/2, −z+1/2; (iii) x−1/2, −y+1/2, z−1/2.
 

Acknowledgements

This work was supported by grants from the New Century Excellent Talents Scheme of the Ministry of Education (NCET-08-0612), the Fundamental Research Funds for the Central Universities (21609202) and the Team Project of the Natural Science Foundation of Guangdong Province (No. 8351063201000003). We also thank Mr Guo-Qiang Li for the data collection.

References

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3096
doi:10.1107/S1600536811043868
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