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Acta Crystallogr Sect E Struct Rep Online. 2010 February 1; 66(Pt 2): o318.
Published online 2010 January 9. doi:  10.1107/S1600536810000413
PMCID: PMC2979717

6-Amino-9H-purine-1,7-diium bis­(4-methyl­benzene­sulfonate) monohydrate

Abstract

The asymmetric unit of the title compound, C5H7N5 2+·2C7H7O3S·H2O, consists of one diprotonated adeninium cation, two p-toluene­sulfonic acid anions and one water mol­ecule. In the crystal, the cations and anions are connected through N—H(...)O hydrogen bonds forming R 2 2(8) and R 2 2(9) graph-set motifs. The solvent water mol­ecule links cations and anions through O—H(...)O and N—H(...)O hydrogen bonds, generating a two-dimensional layer parallel to (10An external file that holds a picture, illustration, etc.
Object name is e-66-0o318-efi1.jpg).

Related literature

For biological activity of purine and its derivatives, see: Barral et al. (2006 [triangle]); Sridhar & Ravikumar (2007 [triangle]); Sridhar et al. (2009 [triangle]); Xing et al. (2008 [triangle]). For hydrogen-bonding motifs, see: Etter (1990 [triangle]); Bernstein et al. (1995 [triangle]).

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Object name is e-66-0o318-scheme1.jpg

Experimental

Crystal data

  • C5H7N5 2+·2C7H7O3S·H2O
  • M r = 497.54
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o318-efi2.jpg
  • a = 16.2462 (11) Å
  • b = 6.0370 (4) Å
  • c = 22.7390 (15) Å
  • β = 90.625 (1)°
  • V = 2230.1 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.29 mm−1
  • T = 296 K
  • 0.31 × 0.21 × 0.21 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2006 [triangle]) T min = 0.915, T max = 0.942
  • 16652 measured reflections
  • 4153 independent reflections
  • 3452 reflections with I > 2σ(I)
  • R int = 0.100

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.120
  • S = 1.05
  • 4153 reflections
  • 300 parameters
  • H-atom parameters constrained
  • Δρmax = 0.46 e Å−3
  • Δρmin = −0.31 e Å−3

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 [triangle]), ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and CAMERON (Pearce et al., 2000 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810000413/dn2513sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810000413/dn2513Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by the National Natural Science Foundation of China (20662007).

supplementary crystallographic information

Comment

Purin and its derivatives, as one kind of important nucleobase compounds, are essential for understanding many mechanisms of basic importance in the biological process (Xing et al., 2008), and belongs to a group of cytokinin-derived compounds which are indispensable for plant growth. The concept of the acyclic nucleoside phosphonate (ANPs) has been used to design chain terminators for antiviral and therapy proved to be valid (Barral et al., 2006). In C5H6N5+.C8H7O2.C8H8O2.H2O and C5H6N5+.C4H3O4.H2O compounds, the adeninium cations form N-H···O hydrogen bonds with their anion counterparts and adeninium-adeninium self-association base pairs (Sridhar et al., 2007). In C5H7N52+.0.5C2O42–.2Clcompound, adenine is doubly protonated, while in C5H6N5+.C2HO4.0.5C2H2O4.H2O compound, adenine is monoprotonated (Sridhar et al., 2009).

In the title compound, C5H7N52+.2C7H7SO3.H2O, the asymmetric unit contains one diprotonated adeninium cation, two p-toluenesulfonic acid anions and one water molecule. The two anions are connected to the purin molecule through N-H···O hydrogen bonds building R22(8) and R22(9) graph set motifs (Table 1, Fig.1) (Etter, 1990; Bernstein et al., 1995) . In the same asymmetric unit, the water molecule is connected through O-H···O hydrogen bond to one of the p-toluenesulfonic acid (Table 1, Fig. 1).

Futhermore The water links cation and anion through O-H···O and N-H···O hydrogen bonds forming a R66(20) graph set motif and buiding a two dimensional layer parallel to the (1 0 -1) plane (Fig. 2, Table 1).

In the 9H-purin-6-amine molecule, all atoms are coplanar, the dihedral angles between the plane of the 9H-purin-6-amine and the benzene rings of the p-toluenesulfonate anions are 87.78 (5)° and 87.15 (5)°, respectively, indicating that the 9H-purin-6-amine is almost perpendicular to the two benzene rings.

Experimental

A mixture of purin-6-amine (10.0 mmol) and toluene sulfonic acid (20.0 mmol) was dissolved in ethanol (40 ml) in batches over a period of 2 h under reflux, heating was continued for 1 h. The mixture was cooled to room temperature and separated, the solvent of the organic phase was removed and the residue recrystallized with ethyl acetate. Yellow crystals of the title compound suitable for X-ray diffraction analysis were obtained after several days. Yield 77.3%.

Refinement

The water H atoms were located in a difference Fourier map but were included in fixed positions in riding-model approximation with the O—H distances in the range 0.8252–0.8381Å and Uiso(H) = 1.5Ueq(O); all other H atoms were placed in geometrically idealized positions with C<–H(methylene) = 0.96 Å, C–H(aromatic) = 0.93 Å, N—H = 0.86 Å, and Uiso(H) = 1.2 Ueq(C,N).

Figures

Fig. 1.
: A view of the structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. Hydrogen bonds are shown as dashed lines.
Fig. 2.
: Partial packing view of the title compound, viewed down the b axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C5H7N52+·2C7H7O3S·H2OF(000) = 1040
Mr = 497.54Dx = 1.482 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 7679 reflections
a = 16.2462 (11) Åθ = 2.5–28.1°
b = 6.0370 (4) ŵ = 0.29 mm1
c = 22.7390 (15) ÅT = 296 K
β = 90.625 (1)°Block, yellow
V = 2230.1 (3) Å30.31 × 0.21 × 0.21 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer4153 independent reflections
Radiation source: fine-focus sealed tube3452 reflections with I > 2σ(I)
graphiteRint = 0.100
[var phi] and ω scansθmax = 25.5°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Bruker, 2006)h = −19→19
Tmin = 0.915, Tmax = 0.942k = −7→7
16652 measured reflectionsl = −27→26

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.05w = 1/[σ2(Fo2) + (0.059P)2 + 0.6101P] where P = (Fo2 + 2Fc2)/3
4153 reflections(Δ/σ)max < 0.001
300 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = −0.31 e Å3

Special details

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 > 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)

xyzUiso*/Ueq
C10.58230 (11)0.6806 (3)0.70038 (8)0.0345 (4)
C20.68007 (12)0.9106 (3)0.75121 (9)0.0424 (5)
H20.70960.93110.78600.051*
C30.64254 (11)1.0129 (3)0.66210 (8)0.0342 (4)
C40.58820 (11)0.8401 (3)0.65534 (8)0.0342 (4)
C50.58704 (13)1.0362 (3)0.57478 (9)0.0439 (5)
H50.57441.08600.53710.053*
C60.12147 (18)0.2967 (6)0.73440 (13)0.0827 (9)
H6A0.14390.29180.77360.124*
H6B0.09670.15660.72500.124*
H6C0.08060.41130.73190.124*
C70.18958 (15)0.3450 (4)0.69138 (11)0.0578 (6)
C80.19569 (15)0.5466 (4)0.66313 (11)0.0605 (6)
H80.15730.65660.67090.073*
C90.25782 (14)0.5885 (4)0.62340 (10)0.0523 (5)
H90.26090.72540.60480.063*
C100.31520 (12)0.4262 (3)0.61154 (9)0.0410 (5)
C110.30975 (16)0.2236 (4)0.63958 (11)0.0577 (6)
H110.34790.11290.63180.069*
C120.24765 (16)0.1866 (4)0.67901 (12)0.0653 (7)
H120.24490.05010.69790.078*
C130.30034 (16)0.4904 (5)1.01182 (12)0.0714 (8)
H13A0.25020.44420.99280.107*
H13B0.29840.64711.01890.107*
H13C0.30660.41351.04850.107*
C140.37220 (13)0.4378 (4)0.97288 (9)0.0470 (5)
C150.40420 (16)0.5906 (4)0.93554 (12)0.0622 (7)
H150.38130.73170.93440.075*
C160.46944 (16)0.5434 (4)0.89932 (11)0.0595 (6)
H160.49070.65240.87490.071*
C170.50300 (12)0.3336 (3)0.89954 (8)0.0374 (4)
C180.47223 (15)0.1783 (4)0.93719 (10)0.0558 (6)
H180.49490.03690.93820.067*
C190.40759 (15)0.2304 (4)0.97374 (11)0.0599 (6)
H190.38760.12360.99940.072*
N10.53750 (11)0.5001 (3)0.69920 (7)0.0431 (4)
H1A0.53840.41090.72870.052*
H1B0.50720.47080.66890.052*
N20.63051 (10)0.7299 (3)0.74765 (7)0.0397 (4)
H2A0.62960.64120.77720.048*
N30.68966 (10)1.0571 (3)0.71004 (7)0.0398 (4)
N40.64043 (10)1.1311 (3)0.61096 (7)0.0394 (4)
H40.66901.24760.60360.047*
N50.55420 (10)0.8603 (3)0.59990 (7)0.0416 (4)
H5A0.51800.77380.58440.050*
O10.40025 (13)0.7072 (3)0.55042 (8)0.0729 (5)
O20.37421 (11)0.3460 (3)0.50891 (7)0.0669 (5)
O30.46938 (10)0.3929 (4)0.58895 (7)0.0720 (5)
O40.53719 (10)0.2035 (3)0.79461 (6)0.0519 (4)
O50.63123 (10)0.4573 (3)0.84146 (6)0.0547 (4)
O60.62452 (10)0.0766 (3)0.87476 (7)0.0567 (4)
O70.28741 (10)0.4810 (2)0.40726 (7)0.0553 (4)
H1W0.23750.46160.39920.083*
H2W0.29880.43230.44030.083*
S10.57997 (3)0.26166 (8)0.84914 (2)0.04219 (17)
S20.39453 (3)0.47017 (9)0.56027 (2)0.04297 (17)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0338 (9)0.0381 (10)0.0317 (9)0.0065 (8)0.0063 (8)0.0004 (7)
C20.0416 (11)0.0517 (12)0.0336 (10)0.0055 (9)−0.0047 (8)−0.0050 (9)
C30.0328 (9)0.0382 (9)0.0316 (9)0.0051 (7)0.0052 (7)−0.0012 (7)
C40.0346 (9)0.0406 (10)0.0275 (9)0.0017 (8)0.0024 (7)0.0000 (7)
C50.0521 (12)0.0470 (11)0.0326 (10)−0.0033 (9)−0.0002 (9)0.0057 (8)
C60.0648 (17)0.112 (2)0.0718 (19)−0.0161 (16)0.0225 (15)0.0054 (17)
C70.0492 (13)0.0741 (16)0.0503 (13)−0.0088 (12)0.0086 (10)0.0015 (12)
C80.0550 (14)0.0653 (15)0.0614 (15)0.0093 (12)0.0104 (12)−0.0015 (12)
C90.0560 (13)0.0478 (12)0.0531 (13)0.0019 (10)0.0022 (11)0.0063 (10)
C100.0415 (11)0.0442 (11)0.0372 (10)−0.0045 (9)−0.0008 (8)0.0013 (8)
C110.0584 (14)0.0510 (13)0.0639 (15)0.0063 (11)0.0151 (12)0.0119 (11)
C120.0716 (17)0.0554 (14)0.0692 (16)−0.0057 (12)0.0161 (13)0.0190 (12)
C130.0567 (15)0.096 (2)0.0615 (16)0.0150 (14)0.0110 (13)−0.0165 (14)
C140.0411 (11)0.0591 (13)0.0408 (11)0.0044 (10)0.0006 (9)−0.0061 (10)
C150.0678 (16)0.0438 (12)0.0752 (17)0.0182 (11)0.0124 (13)0.0016 (11)
C160.0696 (16)0.0404 (11)0.0687 (16)0.0089 (11)0.0183 (13)0.0168 (11)
C170.0373 (10)0.0396 (10)0.0354 (10)0.0028 (8)0.0009 (8)0.0067 (8)
C180.0631 (14)0.0431 (11)0.0616 (14)0.0145 (11)0.0203 (12)0.0172 (10)
C190.0622 (15)0.0613 (15)0.0568 (14)0.0064 (11)0.0233 (12)0.0174 (11)
N10.0495 (10)0.0433 (9)0.0364 (9)−0.0034 (8)0.0008 (7)0.0074 (7)
N20.0455 (9)0.0448 (9)0.0286 (8)0.0059 (7)0.0007 (7)0.0048 (7)
N30.0354 (9)0.0472 (9)0.0368 (9)0.0007 (7)−0.0010 (7)−0.0037 (7)
N40.0404 (9)0.0411 (9)0.0367 (9)−0.0048 (7)0.0047 (7)0.0043 (7)
N50.0485 (10)0.0443 (9)0.0319 (8)−0.0097 (8)−0.0050 (7)0.0037 (7)
O10.0845 (13)0.0551 (10)0.0795 (13)−0.0160 (9)0.0234 (10)0.0090 (9)
O20.0717 (11)0.0869 (12)0.0421 (9)−0.0227 (10)0.0037 (8)−0.0136 (8)
O30.0437 (9)0.1191 (16)0.0532 (10)0.0023 (10)−0.0032 (8)−0.0017 (10)
O40.0592 (9)0.0593 (9)0.0374 (8)−0.0005 (7)0.0032 (7)0.0043 (7)
O50.0508 (9)0.0690 (10)0.0443 (9)−0.0112 (7)0.0028 (7)0.0169 (7)
O60.0532 (9)0.0628 (10)0.0543 (9)0.0222 (8)0.0087 (7)0.0125 (7)
O70.0526 (9)0.0561 (9)0.0571 (9)−0.0114 (7)0.0004 (8)0.0093 (7)
S10.0414 (3)0.0495 (3)0.0358 (3)0.0052 (2)0.0047 (2)0.0099 (2)
S20.0426 (3)0.0509 (3)0.0354 (3)−0.0092 (2)0.0005 (2)0.0004 (2)

Geometric parameters (Å, °)

C1—N11.311 (2)C13—C141.507 (3)
C1—N21.356 (2)C13—H13A0.9600
C1—C41.410 (3)C13—H13B0.9600
C2—N31.299 (3)C13—H13C0.9600
C2—N21.357 (3)C14—C151.361 (3)
C2—H20.9300C14—C191.377 (3)
C3—N31.352 (2)C15—C161.379 (3)
C3—N41.365 (2)C15—H150.9300
C3—C41.374 (3)C16—C171.379 (3)
C4—N51.376 (2)C16—H160.9300
C5—N41.320 (3)C17—C181.368 (3)
C5—N51.321 (3)C17—S11.760 (2)
C5—H50.9300C18—C191.382 (3)
C6—C71.513 (3)C18—H180.9300
C6—H6A0.9600C19—H190.9300
C6—H6B0.9600N1—H1A0.8602
C6—H6C0.9600N1—H1B0.8608
C7—C121.374 (4)N2—H2A0.8595
C7—C81.380 (4)N4—H40.8601
C8—C91.385 (3)N5—H5A0.8592
C8—H80.9300O1—S21.4513 (18)
C9—C101.381 (3)O2—S21.4237 (16)
C9—H90.9300O3—S21.4506 (17)
C10—C111.383 (3)O4—S11.4576 (16)
C10—S21.767 (2)O5—S11.4569 (16)
C11—C121.375 (3)O6—S11.4498 (15)
C11—H110.9300O7—H1W0.8376
C12—H120.9300O7—H2W0.8259
N1—C1—N2120.98 (17)C15—C14—C19117.6 (2)
N1—C1—C4126.53 (17)C15—C14—C13121.8 (2)
N2—C1—C4112.49 (17)C19—C14—C13120.6 (2)
N3—C2—N2125.47 (18)C14—C15—C16122.3 (2)
N3—C2—H2117.3C14—C15—H15118.9
N2—C2—H2117.3C16—C15—H15118.9
N3—C3—N4126.33 (17)C17—C16—C15119.6 (2)
N3—C3—C4126.72 (17)C17—C16—H16120.2
N4—C3—C4106.96 (16)C15—C16—H16120.2
C3—C4—N5106.63 (16)C18—C17—C16119.0 (2)
C3—C4—C1119.08 (17)C18—C17—S1120.36 (16)
N5—C4—C1134.12 (18)C16—C17—S1120.54 (16)
N4—C5—N5110.20 (17)C17—C18—C19120.4 (2)
N4—C5—H5124.9C17—C18—H18119.8
N5—C5—H5124.9C19—C18—H18119.8
C7—C6—H6A109.5C14—C19—C18121.2 (2)
C7—C6—H6B109.5C14—C19—H19119.4
H6A—C6—H6B109.5C18—C19—H19119.4
C7—C6—H6C109.5C1—N1—H1A120.0
H6A—C6—H6C109.5C1—N1—H1B120.0
H6B—C6—H6C109.5H1A—N1—H1B120.0
C12—C7—C8117.7 (2)C1—N2—C2124.11 (16)
C12—C7—C6120.5 (2)C1—N2—H2A117.9
C8—C7—C6121.8 (2)C2—N2—H2A118.0
C7—C8—C9121.4 (2)C2—N3—C3112.03 (17)
C7—C8—H8119.3C5—N4—C3108.31 (16)
C9—C8—H8119.3C5—N4—H4125.9
C10—C9—C8119.7 (2)C3—N4—H4125.8
C10—C9—H9120.1C5—N5—C4107.90 (16)
C8—C9—H9120.1C5—N5—H5A126.1
C9—C10—C11119.4 (2)C4—N5—H5A126.0
C9—C10—S2121.40 (16)H1W—O7—H2W110.9
C11—C10—S2119.21 (17)O6—S1—O5112.91 (10)
C12—C11—C10119.7 (2)O6—S1—O4112.80 (10)
C12—C11—H11120.1O5—S1—O4111.18 (9)
C10—C11—H11120.1O6—S1—C17106.48 (9)
C7—C12—C11122.0 (2)O5—S1—C17106.79 (10)
C7—C12—H12119.0O4—S1—C17106.13 (9)
C11—C12—H12119.0O2—S2—O3112.64 (12)
C14—C13—H13A109.5O2—S2—O1114.04 (12)
C14—C13—H13B109.5O3—S2—O1109.38 (13)
H13A—C13—H13B109.5O2—S2—C10107.32 (10)
C14—C13—H13C109.5O3—S2—C10105.60 (10)
H13A—C13—H13C109.5O1—S2—C10107.35 (10)
H13B—C13—H13C109.5
N3—C3—C4—N5−179.98 (17)C13—C14—C19—C18178.4 (2)
N4—C3—C4—N5−0.4 (2)C17—C18—C19—C140.6 (4)
N3—C3—C4—C1−4.1 (3)N1—C1—N2—C2178.16 (18)
N4—C3—C4—C1175.47 (16)C4—C1—N2—C2−1.0 (3)
N1—C1—C4—C3−175.61 (18)N3—C2—N2—C1−1.6 (3)
N2—C1—C4—C33.5 (2)N2—C2—N3—C31.3 (3)
N1—C1—C4—N5−1.2 (3)N4—C3—N3—C2−177.93 (18)
N2—C1—C4—N5177.89 (19)C4—C3—N3—C21.6 (3)
C12—C7—C8—C90.3 (4)N5—C5—N4—C3−0.2 (2)
C6—C7—C8—C9−179.4 (2)N3—C3—N4—C5179.97 (18)
C7—C8—C9—C100.0 (4)C4—C3—N4—C50.4 (2)
C8—C9—C10—C110.0 (3)N4—C5—N5—C40.0 (2)
C8—C9—C10—S2178.90 (18)C3—C4—N5—C50.3 (2)
C9—C10—C11—C12−0.3 (4)C1—C4—N5—C5−174.7 (2)
S2—C10—C11—C12−179.2 (2)C18—C17—S1—O6−26.8 (2)
C8—C7—C12—C11−0.6 (4)C16—C17—S1—O6157.08 (19)
C6—C7—C12—C11179.1 (3)C18—C17—S1—O5−147.66 (19)
C10—C11—C12—C70.6 (4)C16—C17—S1—O536.2 (2)
C19—C14—C15—C160.2 (4)C18—C17—S1—O493.6 (2)
C13—C14—C15—C16−179.4 (2)C16—C17—S1—O4−82.5 (2)
C14—C15—C16—C171.4 (4)C9—C10—S2—O2−106.24 (19)
C15—C16—C17—C18−2.0 (4)C11—C10—S2—O272.7 (2)
C15—C16—C17—S1174.2 (2)C9—C10—S2—O3133.38 (19)
C16—C17—C18—C191.0 (4)C11—C10—S2—O3−47.7 (2)
S1—C17—C18—C19−175.2 (2)C9—C10—S2—O116.7 (2)
C15—C14—C19—C18−1.2 (4)C11—C10—S2—O1−164.35 (19)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···O40.861.952.813 (2)178
N1—H1B···O30.861.972.805 (2)163
N2—H2A···O50.861.842.694 (2)178
N4—H4···O7i0.861.802.653 (2)170
N5—H5A···O10.862.092.884 (3)152
N5—H5A···O30.862.433.149 (3)141
O7—H1W···O6ii0.841.932.762 (2)176
O7—H2W···O20.832.042.815 (2)156

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: DN2513).

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