2-Ethyl-6-methyl­pyridin-3-ol and its salt bis­(2-ethyl-3-hy­droxy-6-methyl­pyridinium) succinate

The title compounds, C₈H₁₁NO, (I), and 2C₈H₁₂NO⁺·C₄H₄O₄^2-, (II), both crystallize in the monoclinic space group P2₁/c. In the crystal structure of (I), inter­molecular O-H...N hydrogen bonds combine the mol­ecules into polymeric chains extending along the c axis. The chains are linked by C-H...[pi] inter­actions between the methyl­ene H atoms and the pyridine rings into polymeric layers parallel to the ac plane. In the crystal structure of (II), the succinate anion lies on an inversion centre. Its carboxyl­ate groups inter­act with the 2-ethyl-3-hy­droxy-6-methyl­pyridinium cations via inter­mole­cular N-H...O hydrogen bonds with the pyridine ring H atoms and O-H...O hydrogen bonds with the hydroxy H atoms to form polymeric chains, which extend along the [01] direction and comprise R₄⁴(18) hydrogen-bonded ring motifs. These chains are linked to form a three-dimensional network through nonclassical C-H...O hydrogen bonds between the pyridine ring H atoms and the hydroxy-group O atoms of neighbouring cations. [pi]-[pi] inter­actions between the pyridine rings and C-H...[pi] inter­actions between the methyl­ene H atoms of the succinate anion and the pyridine rings are also present in this network.

S1. Comment

2-Ethyl-6-methylpyridin-3-ol belongs to the class of 3-hydroxypiridines, which are the structural analogues of vitamin B6. 2-Ethyl-6-methylpyridin-3-ol shows antioxidant (Klebanov et al., 2001) and antihypoxant (Volchegorskii et al., 2011) activity. Its succinic acid derivative, with a molar ratio of pyridine and succinic acid components of 1:1, is widely used in medical practice as a nootropic (Voronina, 1992, and references therein) and cardioprotective (Sidorenko et al., 2011) drug. Recently, it was found that a succinate salt of 2-ethyl-6-methylpyridin-3-ol, with a molar ratio of pyridine and succinic acid components of 2:1, shows a wide spectrum of biological activities (Gan'shina et al., 2011). It should be noted that the succinic acid component increases the water solubility of 2-ethyl-6-methylpyridin-3-ol and improves the antihypoxic action of 3-hydroxypyridine derivatives (Glushkov et al., 2011).

These pharmaceutical applications of succinic acid derivatives of 2-ethyl-6-methylpyridin-3-ol have initiated their structural investigations. Recently, we have synthesized two salts of 2-ethyl-6-methylpyridin-3-ol, containing pyridine and succinic acid components in a molar ratio of 1:1, and described their crystal structures (Lyakhov et al., 2012). The compounds were found to have the compositions C₈H₁₂NO⁺.C₄H₅O₄^- (a hydrogen succinate salt) and 2(C₈H₁₂NO⁺).C₄H₄O₄^2-.C₄H₆O₄ (a succinate salt with co-crystallized succinic acid molecules). However, no crystal data have been published for the succinate salt with a molar ratio of components of 2:1, nor for 2-ethyl-6-methylpyridin-3-ol itself [Cambridge Structural Database (CSD), Version 5.33, November 2011; Allen, 2002].

The aim of this work was to investigate the crystal structure of pure 2-ethyl-6-methylpyridin-3-ol, (I) (Fig. 1), and to synthesize and structurally characterize its succinate derivative bis(2-ethyl-3-hydroxy-6-methylpyridinium) succinate, (II) (Fig. 2). As the first step of our investigation, we tried to prepare salt (II) by reaction of (I) with succinic acid, taken in molar ratios of (2.5–3):1 in organic solvents (acetone or propan-2-ol). However, crystallization of the reaction mixture gave only one crystalline product, bis(2-ethyl-3-hydroxy-6-methylpyridinium) succinate–succinic acid (1/1), (III), which was investigated earlier (Lyakhov et al., 2012). Our next study showed that salt (II) could be obtained by melting equimolar amounts of (I) and (III) (see Experimental).

Compound (I) crystallizes in the monoclinic space group P2₁/c, with Z = 4. The asymmetric unit comprises one molecule of 2-ethyl-6-methylpyridin-3-ol, and bond lengths and angles lie in expected ranges. There are intermolecular O—H···N hydrogen bonds (Table 1) between the hydroxyl H atoms and the pyridine ring N atoms, linking the molecules into polymeric chains extending along the c axis (Fig. 3). There are also C—H···π interactions between methylene atom H7A of one molecule and the pyridine ring of another molecule at (1 + x, y, z), with distances H7A···Cg = 2.97 Å and C7···Cg = 3.59 Å, and angle C7—H7A···Cg = 123°, and with the angle between the H7A···Cg vector and the normal to the pyridine ring plane being ca 2° (Cg denotes the centroid of the pyridine ring). These weak interactions also combine the molecules into polymeric chains extending along the a axis (Fig. 4), connecting the above-mentioned hydrogen-bonded polymeric chains into layers parallel to the ac plane.

Compound (II) is also monoclinic, with the same space group P2₁/c. The asymmetric unit contains one 2-ethyl-3-hydroxy-6-methylpyridinium cation and one-half of a fully deprotonated succinate anion. All atoms occupy general sites. The geometry of the 2-ethyl-3-hydroxy-6-methylpyridinium cation is close to that of the 2-ethyl-6-methylpyridin-3-ol molecule in (I). The succinate anion is centrosymmetric, and the bond lengths and valence angles are in the expected ranges. In the carboxylate groups, bonds C10—O1 and C10—O2 are close in length, being 1.2449 (16) and 1.2472 (18) Å, respectively. As expected, the non-H skeleton of the succinate anion shows a planar configuration, corresponding to non-crystallographic symmetry C_2h, with an r.m.s. deviation from planarity of ca 0.066 Å (Pilati & Forni, 1998). This structural feature is driven by the stable planar conformation of the succinate derivatives, combined with directional hydrogen-bonding interactions in the crystal structure of (II).

In the crystal structure of (II), all succinate O atoms are involved in intermolecular hydrogen bonds (Table 2, Fig. 5). Each anion is bonded to four 2-ethyl-3-hydroxy-6-methylpyridinium cations via N—H···O hydrogen bonds with the pyridine ring H atoms, and O—H···O hydrogen bonds with the hydroxyl H atoms. These bonds are responsible for formation of polymeric chains extending along the [101] direction. The chains are located around the planes y = 0 and y = 1/2. An arrangement of the chains located around the plane y = 1/2 is shown in Fig. 6. In the chains, two 2-ethyl-3-hydroxy-6-methylpyridinium cations interact with two carboxylate groups of two succinate anions to form centrosymmetric R₄⁴(18) ring motifs (Bernstein et al., 1995). The chains are linked together by non-classical C—H···O hydrogen bonds (Fig. 5) between a pyridine ring H atom and the hydroxyl group O atom of a neighbouring cation to give a three-dimensional network.

There are π–π interactions in (II) between the pyridine rings, with a centroid-to-centroid (Cg···Cg^v) distance of 3.70 Å [symmetry code: (v) 2 - x, 1 - y, 2 - z] and an offset of 1.55 Å. They are responsible for the formation of cationic dimers (Fig. 6). There are also C—H···π interactions between methylene atom H11B of the succinate anion and the pyridine ring of the cation at (1 - x, 1 - y, 1 - z), with distances H11B···Cg = 2.78 Å and C11···Cg = 3.71 Å, and angle C11—H11B···Cg = 161°, and with the angle between the H11B···Cg vector and the normal to the pyridine ring plane being ca 11°. Each succinate anion is bonded to two cations due to these interactions. The combined action of these π–π and C—H···π contacts links the cations and anions into polymeric chains, extending along the [101] direction (Fig. 6).

Related literature

For related literature, see: Allen (2002); Bernstein et al. (1995); Gan'shina, Gorbunov, Gnezdilova, Kurdiumov, Avdiunina, Piatin & Mirzoian (2011); Glushkov et al. (2011); Klebanov et al. (2001); Lyakhov et al. (2012); Pilati & Forni (1998); Sidorenko et al. (2011); Volchegorskii et al. (2011); Voronina (1992).

S2. Experimental

Compound (I) was obtained from a commercial source and used without further purification. Single crystals of (I) suitable for X-ray analysis were prepared by recrystallization from an acetone solution of (I).

For the synthesis of compound (II), bis(2-ethyl-3-hydroxy-6-methylpyridinium) succinate–succinic acid, (III) (1.0 g, 3.9 mmol), was melted down at ca 388 K. Compound (I) (0.54 g, 3.9 mmol) was added to the melt and the mixture was stirred for 15 min at ca 388 K, then left to cool to room temperature overnight. As a result, a fine polycrystalline powder of (II) was obtained (yield 0.9 g, 59%; m.p. 387–389 K). Spectroscopic analysis: ¹H NMR (500 MHz, D₂O, δ, p.p.m.): 1.16 (t, 3H, J = 7.5 Hz, CH₂CH₃), 2.43 (s, 2H, CH₂CH₂), 2.48 (s, 3H, CH₃), 2.84 (q, 2H, J = 7.5 Hz, CH₂CH₃), 7.34 (d, 1H, J = 9 Hz, aryl), 7.66 (d, 1H, J = 9 Hz, aryl).

Single crystals of (II) suitable for X-ray analysis were prepared by reaction of (III) with (I) (the amounts of the compounds were the same as above) in refluxing acetone (30 ml) for 15 min, and subsequent crystallization using seed crystals of (II) [In what solvent?].

S3. Refinement

For (I), H atoms were included in geometrically calculated positions, with O—H = 0.82 Å and C—H = 0.93 (aromatic), 0.96 (methyl) or 0.97 Å (methylene), and refined using a riding model, with U_iso(H) = 1.5U_eq(C,O) for methyl and hydroxyl H, or 1.2U_eq(C,N) for other H atoms.

For (II), the H atoms of the N—H and O—H groups were located in a Fourier map and refined isotropically, with U_iso(H) = 1.2U_eq(N) or 1.5U_eq(O), respectively. The H atoms of the methyl, methylene and aromatic C—H groups were treated in the same way as for (I).

Computing details

For both compounds, data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. The 2-ethyl-3-hydroxy-6-methylpyridinium cation and succinate anion in the crystal structure of (II) with the atom-numbering scheme for the asymmetric unit. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 3. The crystal packing of (I), viewed along the a axis. Dashed lines indicate hydrogen bonds.
	Fig. 4. A polymeric chain in the crystal structure of (I), formed by C—H···π interactions (dashed lines) and running along the a axis. Only H atoms participating in these interactions are shown.
	Fig. 5. The hydrogen bonding (dashed lines) in the crystal structure of (II). Symmetry codes correspond to those in Table 2. The ethyl and methyl groups, and H atoms not participating in hydrogen bonds, have been omitted for clarity.
	Fig. 6. An arrangement of hydrogen-bonded (N—H···O and O—H···O) polymeric chains (double-dashed lines) in the crystal structure of (II), located around the plane y = 1/2. C—H···π and π–π interactions (single dashed lines) are also shown. The ethyl and methyl groups have been omitted. Only H atoms participating in the interactions are shown.

(I) 2-ethyl-6-methylpyridin-3-ol

Crystal data

C8H11NO	F(000) = 296
Mr = 137.18	Dx = 1.151 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2844 reflections
a = 4.7710 (1) Å	θ = 3.3–30.5°
b = 14.5605 (3) Å	µ = 0.08 mm^−1
c = 11.4070 (2) Å	T = 296 K
β = 91.974 (1)°	Prism, colourless
V = 791.95 (3) Å^3	0.39 × 0.38 × 0.24 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer	1813 independent reflections
Radiation source: fine-focus sealed tube	1297 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.018
ϕ and ω scans	θmax = 27.5°, θmin = 2.8°
Absorption correction: multi-scan SADABS (Bruker, 2008)	h = −6→6
Tmin = 0.971, Tmax = 0.982	k = −18→17
7973 measured reflections	l = −12→14

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.045	H-atom parameters constrained
wR(F^2) = 0.149	w = 1/[σ^2(Fo^2) + (0.0695P)^2 + 0.141P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
1813 reflections	Δρmax = 0.18 e Å^−3
95 parameters	Δρmin = −0.12 e Å^−3
0 restraints	Extinction correction: SHELXL (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.047 (8)

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 (Ų)

	x	y	z	Uiso*/Ueq
N1	0.1123 (3)	0.70018 (9)	0.10545 (9)	0.0551 (4)
C2	0.2296 (3)	0.75574 (10)	0.02827 (10)	0.0512 (4)
C3	0.1544 (3)	0.75120 (11)	−0.09161 (11)	0.0540 (4)
C4	−0.0459 (3)	0.68869 (12)	−0.12729 (12)	0.0643 (5)
H4	−0.1015	0.6846	−0.2061	0.077*
C5	−0.1641 (4)	0.63217 (12)	−0.04636 (14)	0.0691 (5)
H5	−0.2997	0.5896	−0.0703	0.083*
C6	−0.0822 (3)	0.63836 (11)	0.07025 (13)	0.0603 (4)
C7	0.4364 (4)	0.82561 (13)	0.07261 (13)	0.0715 (5)
H7A	0.5832	0.8323	0.0165	0.086*
H7B	0.5224	0.8042	0.1459	0.086*
C8	0.3030 (6)	0.91738 (16)	0.0920 (2)	0.1182 (10)
H8A	0.2269	0.9405	0.0187	0.177*
H8B	0.4415	0.9595	0.1231	0.177*
H8C	0.1554	0.9110	0.1465	0.177*
O3	0.2846 (3)	0.80884 (9)	−0.16434 (8)	0.0752 (4)
H3	0.2287	0.7994	−0.2320	0.113*
C9	−0.2040 (5)	0.57865 (14)	0.16298 (18)	0.0868 (6)
H9A	−0.0565	0.5446	0.2024	0.130*
H9B	−0.3366	0.5367	0.1271	0.130*
H9C	−0.2970	0.6164	0.2187	0.130*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0661 (8)	0.0665 (8)	0.0329 (5)	0.0100 (6)	0.0028 (5)	−0.0014 (5)
C2	0.0554 (8)	0.0652 (9)	0.0329 (6)	0.0062 (6)	−0.0004 (5)	−0.0052 (6)
C3	0.0573 (8)	0.0728 (10)	0.0318 (6)	0.0005 (7)	0.0012 (5)	−0.0030 (6)
C4	0.0694 (10)	0.0864 (12)	0.0365 (7)	−0.0058 (8)	−0.0046 (6)	−0.0091 (7)
C5	0.0752 (11)	0.0741 (11)	0.0580 (9)	−0.0119 (8)	0.0019 (8)	−0.0130 (8)
C6	0.0722 (10)	0.0603 (9)	0.0489 (8)	0.0053 (7)	0.0101 (7)	−0.0013 (7)
C7	0.0793 (11)	0.0919 (13)	0.0425 (8)	−0.0130 (9)	−0.0083 (7)	−0.0086 (8)
C8	0.146 (2)	0.0869 (15)	0.125 (2)	−0.0335 (15)	0.0563 (17)	−0.0354 (14)
O3	0.0876 (8)	0.1045 (10)	0.0333 (5)	−0.0243 (7)	−0.0001 (5)	0.0035 (5)
C9	0.1105 (15)	0.0769 (12)	0.0744 (12)	−0.0050 (11)	0.0236 (11)	0.0110 (9)

Geometric parameters (Å, º)

N1—C2	1.3330 (18)	C7—C8	1.500 (3)
N1—C6	1.344 (2)	C7—H7A	0.9700
C2—C3	1.4033 (17)	C7—H7B	0.9700
C2—C7	1.493 (2)	C8—H8A	0.9600
C3—O3	1.3469 (17)	C8—H8B	0.9600
C3—C4	1.371 (2)	C8—H8C	0.9600
C4—C5	1.372 (2)	O3—H3	0.8200
C4—H4	0.9300	C9—H9A	0.9600
C5—C6	1.376 (2)	C9—H9B	0.9600
C5—H5	0.9300	C9—H9C	0.9600
C6—C9	1.502 (2)
C2—N1—C6	120.68 (11)	C8—C7—H7A	109.2
N1—C2—C3	121.06 (13)	C2—C7—H7B	109.2
N1—C2—C7	118.51 (11)	C8—C7—H7B	109.2
C3—C2—C7	120.39 (13)	H7A—C7—H7B	107.9
O3—C3—C4	124.21 (12)	C7—C8—H8A	109.5
O3—C3—C2	117.58 (13)	C7—C8—H8B	109.5
C4—C3—C2	118.20 (14)	H8A—C8—H8B	109.5
C3—C4—C5	119.78 (13)	C7—C8—H8C	109.5
C3—C4—H4	120.1	H8A—C8—H8C	109.5
C5—C4—H4	120.1	H8B—C8—H8C	109.5
C4—C5—C6	120.08 (15)	C3—O3—H3	109.5
C4—C5—H5	120.0	C6—C9—H9A	109.5
C6—C5—H5	120.0	C6—C9—H9B	109.5
N1—C6—C5	120.18 (14)	H9A—C9—H9B	109.5
N1—C6—C9	117.21 (15)	C6—C9—H9C	109.5
C5—C6—C9	122.61 (16)	H9A—C9—H9C	109.5
C2—C7—C8	112.24 (16)	H9B—C9—H9C	109.5
C2—C7—H7A	109.2
C6—N1—C2—C3	−0.2 (2)	C3—C4—C5—C6	0.1 (3)
C6—N1—C2—C7	177.65 (13)	C2—N1—C6—C5	−0.5 (2)
N1—C2—C3—O3	−179.22 (13)	C2—N1—C6—C9	−179.86 (14)
C7—C2—C3—O3	3.0 (2)	C4—C5—C6—N1	0.5 (3)
N1—C2—C3—C4	0.8 (2)	C4—C5—C6—C9	179.85 (16)
C7—C2—C3—C4	−177.03 (15)	N1—C2—C7—C8	−95.15 (19)
O3—C3—C4—C5	179.25 (15)	C3—C2—C7—C8	82.7 (2)
C2—C3—C4—C5	−0.7 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···N1^i	0.82	1.92	2.7277 (14)	170

Symmetry code: (i) x, −y+3/2, z−1/2.

(II) bis(2-ethyl-3-hydroxy-6-methylpyridinium) succinate

Crystal data

2C8H12NO^+·C4H4O4^2^−	F(000) = 420
Mr = 392.44	Dx = 1.302 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6266 reflections
a = 8.8445 (1) Å	θ = 2.3–30.6°
b = 13.4026 (2) Å	µ = 0.10 mm^−1
c = 8.4848 (1) Å	T = 296 K
β = 95.347 (1)°	Prism, colourless
V = 1001.41 (2) Å^3	0.53 × 0.32 × 0.30 mm
Z = 2

Data collection

Bruker APEXII CCD area-detector diffractometer	2295 independent reflections
Radiation source: fine-focus sealed tube	1999 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
ϕ and ω scans	θmax = 27.5°, θmin = 2.3°
Absorption correction: multi-scan SADABS (Bruker, 2008)	h = −11→11
Tmin = 0.951, Tmax = 0.972	k = −17→17
10139 measured reflections	l = −8→11

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.045	Hydrogen site location: difference Fourier map
wR(F^2) = 0.136	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0799P)^2 + 0.2525P] where P = (Fo^2 + 2Fc^2)/3
2295 reflections	(Δ/σ)max < 0.001
135 parameters	Δρmax = 0.31 e Å^−3
0 restraints	Δρmin = −0.28 e Å^−3

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 (Ų)

	x	y	z	Uiso*/Ueq
N1	0.76284 (11)	0.47793 (8)	0.94007 (12)	0.0333 (3)
H1	0.7014 (18)	0.4940 (11)	1.0254 (18)	0.040*
C2	0.84014 (13)	0.55289 (9)	0.87948 (14)	0.0320 (3)
C3	0.94671 (14)	0.53016 (9)	0.77388 (15)	0.0351 (3)
C4	0.96533 (16)	0.43072 (10)	0.73254 (17)	0.0428 (3)
H4	1.0347	0.4139	0.6610	0.051*
C5	0.88148 (16)	0.35722 (10)	0.79703 (17)	0.0432 (3)
H5	0.8947	0.2909	0.7689	0.052*
C6	0.77793 (15)	0.38104 (9)	0.90306 (15)	0.0376 (3)
C7	0.80338 (17)	0.65735 (10)	0.92263 (17)	0.0433 (3)
H7A	0.8961	0.6963	0.9356	0.052*
H7B	0.7588	0.6574	1.0228	0.052*
C8	0.6937 (2)	0.70496 (13)	0.7967 (2)	0.0684 (5)
H8A	0.7337	0.6996	0.6957	0.103*
H8B	0.6804	0.7741	0.8218	0.103*
H8C	0.5976	0.6714	0.7928	0.103*
C9	0.6796 (2)	0.30801 (12)	0.9778 (2)	0.0546 (4)
H9A	0.6913	0.3165	1.0906	0.082*
H9B	0.7087	0.2414	0.9517	0.082*
H9C	0.5755	0.3190	0.9391	0.082*
O3	1.02594 (12)	0.60541 (8)	0.71789 (13)	0.0500 (3)
H3	1.119 (3)	0.5807 (16)	0.681 (3)	0.075*
C10	0.61981 (14)	0.49835 (9)	0.31790 (15)	0.0370 (3)
C11	0.49738 (15)	0.52736 (11)	0.42268 (15)	0.0413 (3)
H11A	0.5057	0.5983	0.4444	0.050*
H11B	0.3991	0.5158	0.3648	0.050*
O1	0.60252 (14)	0.52691 (10)	0.17777 (12)	0.0614 (4)
O2	0.72877 (13)	0.44799 (11)	0.37839 (15)	0.0654 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0333 (5)	0.0374 (6)	0.0300 (5)	0.0032 (4)	0.0075 (4)	0.0024 (4)
C2	0.0322 (6)	0.0343 (6)	0.0300 (6)	0.0044 (4)	0.0061 (4)	0.0014 (4)
C3	0.0331 (6)	0.0378 (6)	0.0356 (6)	0.0048 (5)	0.0100 (5)	0.0029 (5)
C4	0.0423 (7)	0.0447 (7)	0.0435 (7)	0.0086 (5)	0.0150 (6)	−0.0058 (5)
C5	0.0477 (7)	0.0349 (6)	0.0472 (7)	0.0047 (5)	0.0058 (6)	−0.0072 (5)
C6	0.0387 (6)	0.0360 (6)	0.0375 (6)	0.0000 (5)	0.0012 (5)	0.0035 (5)
C7	0.0497 (7)	0.0352 (6)	0.0478 (7)	0.0045 (5)	0.0197 (6)	−0.0024 (5)
C8	0.0750 (12)	0.0478 (8)	0.0841 (13)	0.0244 (8)	0.0163 (10)	0.0153 (8)
C9	0.0577 (9)	0.0451 (8)	0.0617 (9)	−0.0090 (7)	0.0094 (7)	0.0099 (7)
O3	0.0441 (6)	0.0445 (6)	0.0662 (7)	0.0037 (4)	0.0298 (5)	0.0078 (5)
C10	0.0374 (6)	0.0399 (6)	0.0366 (6)	−0.0003 (5)	0.0184 (5)	0.0006 (5)
C11	0.0402 (7)	0.0529 (8)	0.0333 (7)	0.0106 (5)	0.0174 (5)	0.0051 (5)
O1	0.0702 (8)	0.0807 (8)	0.0379 (6)	0.0200 (6)	0.0295 (5)	0.0097 (5)
O2	0.0450 (6)	0.0958 (9)	0.0598 (7)	0.0246 (6)	0.0288 (5)	0.0213 (6)

Geometric parameters (Å, º)

N1—C2	1.3441 (16)	C7—H7B	0.9700
N1—C6	1.3455 (16)	C8—H8A	0.9600
N1—H1	0.969 (16)	C8—H8B	0.9600
C2—C3	1.3933 (16)	C8—H8C	0.9600
C2—C7	1.4907 (17)	C9—H9A	0.9600
C3—O3	1.3401 (15)	C9—H9B	0.9600
C3—C4	1.3919 (18)	C9—H9C	0.9600
C4—C5	1.377 (2)	O3—H3	0.97 (2)
C4—H4	0.9300	C10—O1	1.2449 (16)
C5—C6	1.3797 (19)	C10—O2	1.2472 (18)
C5—H5	0.9300	C10—C11	1.5145 (16)
C6—C9	1.4896 (19)	C11—C11^i	1.500 (2)
C7—C8	1.515 (2)	C11—H11A	0.9700
C7—H7A	0.9700	C11—H11B	0.9700
C2—N1—C6	124.55 (11)	H7A—C7—H7B	108.0
C2—N1—H1	117.4 (9)	C7—C8—H8A	109.5
C6—N1—H1	117.6 (9)	C7—C8—H8B	109.5
N1—C2—C3	118.76 (11)	H8A—C8—H8B	109.5
N1—C2—C7	118.54 (10)	C7—C8—H8C	109.5
C3—C2—C7	122.64 (11)	H8A—C8—H8C	109.5
O3—C3—C4	123.59 (11)	H8B—C8—H8C	109.5
O3—C3—C2	118.09 (11)	C6—C9—H9A	109.5
C4—C3—C2	118.32 (12)	C6—C9—H9B	109.5
C5—C4—C3	120.28 (12)	H9A—C9—H9B	109.5
C5—C4—H4	119.9	C6—C9—H9C	109.5
C3—C4—H4	119.9	H9A—C9—H9C	109.5
C4—C5—C6	120.56 (12)	H9B—C9—H9C	109.5
C4—C5—H5	119.7	C3—O3—H3	110.3 (13)
C6—C5—H5	119.7	O1—C10—O2	125.51 (12)
N1—C6—C5	117.50 (12)	O1—C10—C11	116.79 (12)
N1—C6—C9	117.41 (12)	O2—C10—C11	117.69 (11)
C5—C6—C9	125.08 (13)	C11^i—C11—C10	114.99 (14)
C2—C7—C8	111.23 (13)	C11^i—C11—H11A	108.5
C2—C7—H7A	109.4	C10—C11—H11A	108.5
C8—C7—H7A	109.4	C11^i—C11—H11B	108.5
C2—C7—H7B	109.4	C10—C11—H11B	108.5
C8—C7—H7B	109.4	H11A—C11—H11B	107.5
C6—N1—C2—C3	−1.74 (18)	C2—N1—C6—C5	0.86 (19)
C6—N1—C2—C7	175.61 (12)	C2—N1—C6—C9	−178.14 (12)
N1—C2—C3—O3	−178.16 (11)	C4—C5—C6—N1	0.0 (2)
C7—C2—C3—O3	4.60 (19)	C4—C5—C6—C9	178.91 (14)
N1—C2—C3—C4	1.72 (18)	N1—C2—C7—C8	−96.77 (15)
C7—C2—C3—C4	−175.51 (12)	C3—C2—C7—C8	80.47 (17)
O3—C3—C4—C5	178.92 (13)	O1—C10—C11—C11^i	166.38 (16)
C2—C3—C4—C5	−1.0 (2)	O2—C10—C11—C11^i	−13.5 (2)
C3—C4—C5—C6	0.1 (2)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^ii	0.969 (16)	1.686 (16)	2.6538 (14)	176.6 (14)
O3—H3···O2^iii	0.97 (2)	1.53 (2)	2.4932 (13)	175 (2)
C5—H5···O3^iv	0.93	2.58	3.4779 (17)	162

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