4-Meth­oxy­benzamidinium hydrogen sulfate

Irrera, S.; Portalone, G.

doi:10.1107/S1600536812044327

organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Page o3244

doi:10.1107/S1600536812044327

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4-Methoxybenzamidinium hydrogen sulfate

Simona Irrera ^a and Gustavo Portalone ^a ^*

^aChemistry Department, `Sapienza' University of Rome, P. le A. Moro, 5, I-00185 Rome, Italy
^*Correspondence e-mail: g.portalone@caspur.it

(Received 23 October 2012; accepted 25 October 2012; online 31 October 2012)

The title salt, C₈H₁₁N₂O⁺·HSO₄⁻, has been synthesized by the reaction between 4-methoxybenzamidine and sulfuric acid. The asymmetric unit comprises a nonplanar 4-methoxybenzamidinium cation and one hydrogen sulfate anion. In the cation, the amidinium group has two identical C—N bonds [1.306 (2) and 1.308 (2) Å], and its plane forms a dihedral angle of 6.49 (8)° with the mean plane of the benzene ring. The ionic components are associated in the crystal via N—H⁺⋯O⁻, resulting in chains running approximately along the b-axis direction whicg are interconnected by O—H⋯O⁻ hydrogen bonds.

Related literature

For the biological and pharmacological relevance of benzamidine, see: Powers & Harper (1999 ); Grzesiak et al. (2000 ). For structural analysis of proton-transfer adducts containing molecules of biological interest, see: Portalone (2011a ); Portalone & Irrera (2011 ). For the supramolecular association in proton-transfer adducts containing benzamidinium cations, see: Portalone (2010 , 2011b , 2012 ); Irrera & Portalone (2012 ); Irrera et al. (2012 ). For hydrogen-bond motifs, see Bernstein et al. (1995 ).

Experimental

Crystal data

C₈H₁₁N₂O⁺·HSO₄⁻
M_r = 248.26
Monoclinic, P 2₁ /c
a = 14.2608 (14) Å
b = 10.1844 (9) Å
c = 7.5723 (9) Å
β = 94.206 (10)°
V = 1096.83 (19) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 298 K
0.31 × 0.25 × 0.15 mm

Data collection

Oxford Diffraction Xcalibur S CCD diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ) T_min = 0.912, T_max = 0.956
16529 measured reflections
2626 independent reflections
2133 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.114
S = 1.04
2626 reflections
167 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.26 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯O2ⁱ	0.78 (3)	1.79 (3)	2.562 (2)	172 (3)
N1—H1A⋯O4	0.86 (2)	2.10 (2)	2.938 (2)	163 (2)
N1—H1B⋯O5ⁱⁱ	0.84 (2)	2.10 (2)	2.884 (2)	154 (2)
N2—H2A⋯O5	0.84 (2)	2.07 (3)	2.907 (2)	177 (2)
N2—H2B⋯O4ⁱⁱⁱ	0.86 (3)	2.22 (3)	2.965 (2)	145 (3)
Symmetry codes: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) $[-x, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (iii) $[-x, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812044327/rz5020sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812044327/rz5020Isup2.hkl

checkCIF report

Comment top

In our search for new salt compounds as part of investigation of the functionality of biological systems (Portalone, 2011a; Portalone & Irrera, 2011), we have prepared 4-methoxybenzamidinium hydrogen sulfate, (I), which was obtained by a reaction between 4-methoxybenzamidine (4-amidinoanisole) and sulfuric acid.

Benzamidine derivatives, which have shown strong biological and pharmacological activity (Powers & Harper, 1999; Grzesiak et al., 2000), are being used in our group as bricks for supramolecular construction (Portalone, 2010, 2011b, 2012). Indeed, these molecules are strong Lewis bases and their cations can be easily anchored onto numerous inorganic and organic anions and polyanions, largely because of the presence of four potential donor sites for hydrogen-bonding.

The asymmetric unit of (I) comprises one non-planar 4-methoxybenzamidinium cation and one hydrogen sulfate anion (Fig. 1). In the cation the amidinium group forms dihedral angle of 6.49 (8)° with the mean plane of the phenyl ring, which is close to the the values observed in protonated benzamidinium ions (14.4 (1) - 32.7 (1)°, Portalone, 2010, 2012; Irrera et al., 2012). The lack of planarity in all these systems is obviously caused by steric hindrances between the H atoms of the aromatic ring and the amidine moiety. This conformation is rather common in benzamidinium-containing small-molecule crystal structures, with the only exception of benzamidinium diliturate, where the benzamidinium cation is planar (Portalone, 2010). The pattern of bond lengths and bond angles of the 4-methoxybenzamidinium cation agrees with that reported in previous structural investigations (Irrera et al., 2012; Portalone, 2010, 2012; Irrera & Portalone, 2012). In particular the amidinium group, true to one's expectations, features identical C—N bonds within experimental error [1.306 (2) and 1.308 (2) Å], evidencing the delocalization of the π electrons and double-bond character.

Bond lengths in the slightly distorted tetrahedral hydrogen sulfate anion indicate the position of the H atom. There are three short S—O bonds of 1.4504 (13), 1.4442 (13) and 1.4464 (13) Å to terminal atoms O2, O4 and O5, respectively, and one longer bond of 1.5470 (15) Å to atom O3, which is bound to atom H3A.

The ionic components of compound (I) are joined by two N⁺—H···O^- (±) hydrogen bonds (Table 1) to form ionic dimers with graph-set motif R²₂(8) (Bernstein et al., 1995). Analysis of the crystal packing of (I), (Fig. 2), shows that four N⁺—H···O^- hydrogen bonds link the molecular components into a mono-dimensional structure. As previously mentioned, each subunit, built from the ion pairs of the asymmetric unit, forms R²₂(8) dimers via the bidentate interaction of the N—H and S—O groups. Adjacent ion pairs are then linked together by way of the remaining two N⁺—H···O^- hydrogen bonds to form R²₄(8), resulting in chains running approximately along crystallographic b axis. These chains are then interconnected by means of the only O—H···O hydrogen bond present in the structure.

Related literature top

For the biological and pharmacological relevance of benzamidine, see: Powers & Harper (1999); Grzesiak et al. (2000). For structural analysis of proton-transfer adducts containing molecules of biological interest, see: Portalone (2011a); Portalone & Irrera (2011). For the supramolecular association in proton-transfer adducts containing benzamidinium cations, see; Portalone (2010, 2011b, 2012); Irrera & Portalone (2012); Irrera et al. (2012). For hydrogen-bond motifs, see Bernstein et al. (1995).

Experimental top

4-Methoxybenzamidine (0.1 mmol, Fluka at 96% purity) was dissolved without further purification in 6 ml of hot water and heated under reflux for 3 h. While stirring, H₂SO₄ (2 mol L^-1) was added dropwise until pH reached 2. After cooling the solution to an ambient temperature, colourless crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of the solvent after one week.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The asymmetric unit of (I), showing displacements ellipsoids drawn at the 50% probability level. The asymmetric unit was selected so that the two ions are linked by N^+.—H···O^- hydrogen bonds. H atoms are shown as small spheres of arbitrary radii. Hydrogen bonding is indicated by dashed lines.
	Fig. 2. Crystal packing diagram for (I), viewed approximately down the c axis. Displacements ellipsoids are at the 50% probability level. H atoms are shown as small spheres of arbitrary radii. For the sake of clarity, H atoms not involved in hydrogen bonding (dashed lines) have been omitted.

4-Methoxybenzamidinium hydrogen sulfate top

Crystal data top

C₈H₁₁N₂O⁺·HSO₄⁻	F(000) = 520
M_r = 248.26	D_x = 1.503 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybc	Cell parameters from 4647 reflections
a = 14.2608 (14) Å	θ = 2.9–29.7°
b = 10.1844 (9) Å	µ = 0.30 mm⁻¹
c = 7.5723 (9) Å	T = 298 K
β = 94.206 (10)°	Tablets, colourless
V = 1096.83 (19) Å³	0.31 × 0.25 × 0.15 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur S CCD diffractometer	2626 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2133 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
Detector resolution: 16.0696 pixels mm^-1	θ_max = 28.0°, θ_min = 2.9°
ω and ϕ scans	h = −18→18
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	k = −13→13
T_min = 0.912, T_max = 0.956	l = −9→9
16529 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0582P)² + 0.2957P] where P = (F_o² + 2F_c²)/3
2626 reflections	(Δ/σ)_max < 0.001
167 parameters	Δρ_max = 0.26 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₈H₁₁N₂O⁺·HSO₄⁻	V = 1096.83 (19) Å³
M_r = 248.26	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.2608 (14) Å	µ = 0.30 mm⁻¹
b = 10.1844 (9) Å	T = 298 K
c = 7.5723 (9) Å	0.31 × 0.25 × 0.15 mm
β = 94.206 (10)°

Data collection top

Oxford Diffraction Xcalibur S CCD diffractometer	2626 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	2133 reflections with I > 2σ(I)
T_min = 0.912, T_max = 0.956	R_int = 0.036
16529 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.26 e Å⁻³
2626 reflections	Δρ_min = −0.34 e Å⁻³
167 parameters

Special details top

Experimental. Absorption correction: [CrysAlis RED (Oxford Diffraction, 2006); empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm]

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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

	x	y	z	U_iso*/U_eq
S1	−0.16129 (3)	0.16203 (4)	0.84884 (6)	0.03448 (15)
O2	−0.20315 (10)	0.11649 (13)	1.00664 (17)	0.0514 (4)
O3	−0.24735 (9)	0.20809 (15)	0.7284 (2)	0.0498 (4)
H3A	−0.2287 (18)	0.259 (3)	0.662 (4)	0.064 (8)*
O4	−0.09972 (9)	0.27365 (12)	0.87891 (18)	0.0467 (3)
O5	−0.11706 (9)	0.05608 (12)	0.75864 (19)	0.0485 (3)
O1	0.49301 (10)	0.19362 (16)	0.4667 (3)	0.0684 (5)
N1	0.07593 (12)	0.28008 (15)	0.6992 (3)	0.0452 (4)
H1A	0.0189 (18)	0.280 (2)	0.730 (3)	0.053 (6)*
H1B	0.1027 (17)	0.354 (2)	0.693 (3)	0.061 (7)*
N2	0.07598 (14)	0.06125 (17)	0.6593 (3)	0.0595 (5)
H2A	0.0212 (18)	0.058 (2)	0.692 (3)	0.057 (7)*
H2B	0.107 (2)	−0.009 (3)	0.647 (4)	0.087 (9)*
C1	0.21780 (12)	0.18063 (15)	0.6067 (2)	0.0346 (4)
C2	0.26115 (13)	0.30028 (17)	0.5855 (3)	0.0465 (5)
H2	0.2275	0.3770	0.6020	0.056*
C3	0.35275 (14)	0.30917 (18)	0.5407 (3)	0.0497 (5)
H3	0.3806	0.3910	0.5288	0.060*
C4	0.40279 (13)	0.19663 (19)	0.5136 (3)	0.0465 (5)
C5	0.36028 (15)	0.0754 (2)	0.5315 (3)	0.0595 (6)
H5	0.3937	−0.0010	0.5123	0.071*
C6	0.26906 (14)	0.06751 (18)	0.5775 (3)	0.0493 (5)
H6	0.2413	−0.0143	0.5892	0.059*
C7	0.12029 (12)	0.17365 (15)	0.6575 (2)	0.0365 (4)
C8	0.54205 (16)	0.3152 (3)	0.4575 (4)	0.0749 (8)
H8A	0.5094 (10)	0.3716 (13)	0.369 (2)	0.112*
H8B	0.6058 (12)	0.2988 (4)	0.425 (3)	0.112*
H8C	0.5445 (13)	0.3583 (13)	0.573 (2)	0.112*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0360 (3)	0.0244 (2)	0.0440 (3)	−0.00176 (15)	0.00969 (18)	−0.00018 (16)
O2	0.0718 (9)	0.0368 (7)	0.0477 (8)	−0.0093 (6)	0.0198 (7)	0.0026 (6)
O3	0.0352 (7)	0.0531 (8)	0.0616 (9)	−0.0021 (6)	0.0082 (6)	0.0112 (7)
O4	0.0456 (7)	0.0321 (7)	0.0627 (9)	−0.0101 (5)	0.0068 (6)	−0.0029 (6)
O5	0.0488 (7)	0.0302 (6)	0.0688 (9)	0.0022 (5)	0.0193 (6)	−0.0041 (6)
O1	0.0351 (8)	0.0586 (9)	0.1145 (14)	0.0038 (7)	0.0259 (8)	−0.0054 (9)
N1	0.0333 (8)	0.0306 (8)	0.0735 (12)	−0.0025 (6)	0.0154 (8)	−0.0090 (7)
N2	0.0389 (10)	0.0285 (8)	0.1137 (17)	−0.0032 (7)	0.0232 (10)	−0.0039 (9)
C1	0.0304 (8)	0.0282 (8)	0.0454 (9)	0.0011 (6)	0.0031 (7)	−0.0015 (7)
C2	0.0367 (9)	0.0277 (8)	0.0763 (14)	0.0020 (7)	0.0133 (9)	−0.0030 (8)
C3	0.0395 (10)	0.0335 (9)	0.0775 (14)	−0.0050 (8)	0.0137 (9)	−0.0031 (9)
C4	0.0309 (9)	0.0457 (10)	0.0639 (12)	0.0020 (8)	0.0097 (8)	−0.0032 (9)
C5	0.0448 (11)	0.0352 (10)	0.1007 (17)	0.0089 (8)	0.0210 (11)	−0.0056 (10)
C6	0.0423 (10)	0.0277 (8)	0.0793 (14)	0.0008 (7)	0.0132 (9)	−0.0048 (9)
C7	0.0328 (9)	0.0283 (8)	0.0483 (10)	−0.0003 (6)	0.0023 (7)	−0.0020 (7)
C8	0.0381 (12)	0.0773 (17)	0.112 (2)	−0.0104 (11)	0.0238 (13)	−0.0012 (15)

Geometric parameters (Å, º) top

S1—O4	1.4442 (13)	C1—C6	1.391 (2)
S1—O5	1.4464 (13)	C1—C7	1.471 (2)
S1—O2	1.4504 (13)	C2—C3	1.377 (3)
S1—O3	1.5470 (15)	C2—H2	0.9300
O3—H3A	0.78 (3)	C3—C4	1.374 (3)
O1—C4	1.360 (2)	C3—H3	0.9300
O1—C8	1.427 (3)	C4—C5	1.386 (3)
N1—C7	1.306 (2)	C5—C6	1.374 (3)
N1—H1A	0.86 (2)	C5—H5	0.9300
N1—H1B	0.84 (2)	C6—H6	0.9300
N2—C7	1.308 (2)	C8—H8A	0.9739
N2—H2A	0.84 (2)	C8—H8B	0.9739
N2—H2B	0.86 (3)	C8—H8C	0.9739
C1—C2	1.381 (2)

O4—S1—O5	112.37 (8)	C4—C3—H3	120.2
O4—S1—O2	113.83 (8)	C2—C3—H3	120.2
O5—S1—O2	111.75 (8)	O1—C4—C3	124.73 (18)
O4—S1—O3	107.52 (8)	O1—C4—C5	115.75 (17)
O5—S1—O3	107.60 (8)	C3—C4—C5	119.52 (17)
O2—S1—O3	103.05 (9)	C6—C5—C4	120.42 (17)
S1—O3—H3A	106.6 (19)	C6—C5—H5	119.8
C4—O1—C8	118.01 (17)	C4—C5—H5	119.8
C7—N1—H1A	123.0 (15)	C5—C6—C1	120.68 (17)
C7—N1—H1B	119.6 (16)	C5—C6—H6	119.7
H1A—N1—H1B	117 (2)	C1—C6—H6	119.7
C7—N2—H2A	120.2 (16)	N1—C7—N2	118.74 (18)
C7—N2—H2B	118.6 (19)	N1—C7—C1	120.48 (15)
H2A—N2—H2B	120 (2)	N2—C7—C1	120.77 (16)
C2—C1—C6	117.86 (16)	O1—C8—H8A	109.5
C2—C1—C7	120.84 (15)	O1—C8—H8B	109.5
C6—C1—C7	121.29 (15)	H8A—C8—H8B	109.5
C3—C2—C1	121.85 (16)	O1—C8—H8C	109.5
C3—C2—H2	119.1	H8A—C8—H8C	109.5
C1—C2—H2	119.1	H8B—C8—H8C	109.5
C4—C3—C2	119.65 (17)

C6—C1—C2—C3	−1.4 (3)	C3—C4—C5—C6	−0.5 (4)
C7—C1—C2—C3	179.01 (19)	C4—C5—C6—C1	0.0 (4)
C1—C2—C3—C4	0.9 (3)	C2—C1—C6—C5	0.9 (3)
C8—O1—C4—C3	4.9 (3)	C7—C1—C6—C5	−179.5 (2)
C8—O1—C4—C5	−176.0 (2)	C2—C1—C7—N1	−6.3 (3)
C2—C3—C4—O1	179.1 (2)	C6—C1—C7—N1	174.06 (19)
C2—C3—C4—C5	0.1 (3)	C2—C1—C7—N2	172.7 (2)
O1—C4—C5—C6	−179.6 (2)	C6—C1—C7—N2	−6.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱ	0.78 (3)	1.79 (3)	2.562 (2)	172 (3)
N1—H1A···O4	0.86 (2)	2.10 (2)	2.938 (2)	163 (2)
N1—H1B···O5ⁱⁱ	0.84 (2)	2.10 (2)	2.884 (2)	154 (2)
N2—H2A···O5	0.84 (2)	2.07 (3)	2.907 (2)	177 (2)
N2—H2B···O4ⁱⁱⁱ	0.86 (3)	2.22 (3)	2.965 (2)	145 (3)

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

Experimental details

Crystal data
Chemical formula	C₈H₁₁N₂O⁺·HSO₄⁻
M_r	248.26
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	14.2608 (14), 10.1844 (9), 7.5723 (9)
β (°)	94.206 (10)
V (Å³)	1096.83 (19)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.31 × 0.25 × 0.15

Data collection
Diffractometer	Oxford Diffraction Xcalibur S CCD diffractometer
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.912, 0.956
No. of measured, independent and observed [I > 2σ(I)] reflections	16529, 2626, 2133
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.660

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.114, 1.04
No. of reflections	2626
No. of parameters	167
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.26, −0.34

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2ⁱ	0.78 (3)	1.79 (3)	2.562 (2)	172 (3)
N1—H1A···O4	0.86 (2)	2.10 (2)	2.938 (2)	163 (2)
N1—H1B···O5ⁱⁱ	0.84 (2)	2.10 (2)	2.884 (2)	154 (2)
N2—H2A···O5	0.84 (2)	2.07 (3)	2.907 (2)	177 (2)
N2—H2B···O4ⁱⁱⁱ	0.86 (3)	2.22 (3)	2.965 (2)	145 (3)

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

References

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Volume 68| Part 11| November 2012| Page o3244

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