Supra­molecular hydrogen-bonded networks in adeninium phenyl­acetate phenyl­acetic acid monohydrate and adeninium 3-carboxy­propionate monohydrate

In the title compounds, C₅H₆N₅⁺·C₈H₇O₂⁻·C₈H₈O₂·H₂O, (I), and C₅H₆N₅⁺·C₄H₃O₄⁻·H₂O, (II), the adeninium cations form N—H...O hydrogen bonds with their anion counterparts and adeninium–adeninium self-association base pairs with the R₂²(10) motif (Bernstein et al., 1995). A complete hydrogen-bonding motif analysis is presented. Conventional hydrogen bonds lead to layer structures in (I) and to two-dimensional infinite polymeric ribbons in (II). C—H...O inter­actions are found in both structures, while weak π–π stacking inter­actions are only observed in (I).

S1. Comment

Protonated nucleobases are present in many biochemical processes, such as enzymatic reactions and the stabilization of triplex structures, and they play a key role in a newly emerging feature of nucleic acid chemistry, namely acid–base catalysis (Lippert, 2005). Among the nucleobases, adenine shows the widest range of binding possibilities (Salam & Aoki, 2000) because it exhibits at least five donor sites and forms a great variety of complexes. Adenine forms hydrogen bonds with other nucleobases that can lead to the formation of supramolecular structures, which can be of chemical and biological interest (Shipman et al., 2000; Bazzicalupi et al., 2001). Phenylacetic acid has been found to be an active auxin (a type of plant hormone) molecule, predominantly found in fruits and also used in penicillin G production (Hillenga et al., 1995). Succinic acid is a dicarboxylic acid which occurs naturally in plant and animal tissues and plays a significant role in intermediary metabolism (Krebs cycle) in the body. Our particular interest lies in the structure of the crystalline complexes of adenine with aromatic and dicarboxylic acids and examining the interactions between the components. Recently, we reported the crystal structure of bis(adeninium) phthalate phthalic acid 1.45-hydrate (Sridhar & Ravikumar, 2007). In the present study, the crystal structures of adeninium phenylacetate phenylacetic acid hydrate, (I), and adeninium succinate hydrate, (II), are presented

The asymmetric unit of (I) contains one adeninium cation, one phenylacetate anion, one neutral phenylacetic acid and one water molecule (Fig. 1).

Adeninium cations can be either mono- or diprotonated and the bond lengths and angles are dependent on the degree of protonation (Hingerty et al., 1981; Langer & Huml, 1978). It is well documented that the N9H amine form of adenine is the most stable in gas phase and water solution (pK_a = 9.8) (Gu & Leszcynski, 1999; Perun et al., 2005). This canonical tautomeric form contains three basic N atoms. The most basic site (pK_a = 4.2) is N1, which accepts the first proton; the next protonation occurs at N7, and the next at N3.

In both structures, atom N1 is protonated, which can be seen from the increase in the C2—N1—C6 bond angles (Tables 1 and 3); the corresponding value for neutral adenine is 119.8° (Voet & Rich, 1970). The location of the H atom bonded to atom N1 in the difference Fourier map and the successful refinement of this H atom confirmed the site of protonation in both structures.

The adeninium base is nearly planar and the dihedral angle between the least-squares planes through the six- and five-membered rings are 0.42 (9)° for (I) and 0.95 (8)° for (II), respectively.

The molecular geometries of phenylacetic acid in its anionic and neutral forms in (I) are in good agreement with those of a similar structure (Hodgson & Asplund, 1991). The near equality of C—O distances and O—C—C angles (Table 1) clearly shows the existence of the carboxylate group based on C11, whilst differences in the C—O distances and O—C—C angles (Table 1) confirm the carboxyl group (C19). In the phenylacetate anion, the mean plane of the carboxylate group (C11/O1/O2) is rotated from the plane of the benzene ring (C13–C18) by 71.9 (1)°, while in the neutral phenylacetic acid, the plane of the carboxyl group (C19/O3/O4) is rotated by 85.7 (1)° with respect to its attached benzene ring plane (C21–C26).

The asymmetric unit of (II) comprises one adeninium cation, one succinate anion and one water molecule, with one of the carboxyl groups in the succinic acid deprotonated (Fig. 2). The two carboxyl groups are in a cis orientation with respect to the central C—C bond (Table 3). The O—H bond of the carboxyl group is in a trans conformation with respect to the C═O bond of the carboxylate group, as evidenced from the torsion angle H3O—O3—C14—O4 = -177 (1)°. This orientation can be attributed to an intramolecular O—H···O hydrogen bond involving the carboxyl and carboxylate groups of the succinate anion, leading to the formation of an S(7) motif (Bernstein et al., 1995).

In the crystal structure of (I), there are six different modes of hydrogen-bonding interactions viz. cation–cation, cation–anion, cation–neutral, anion–neutral, cation–water and water–anion (Table 2), while in the crystal structure of (II), only four different modes of hydrogen-bonding interactions are observed, viz. cation–cation, cation–anion, anion–anion and water–anion (Table 4). The adeninium cation forms N—H···O hydrogen bonds with the phenylacetate anion, the neutral phenylacetic acid and the water molecule in (I) (Table 2), while in (II), it forms N—H···O hydrogen bonds with only the succinate anion (Table 4). In both structures, intermolecular N—H···N hydrogen bonds involving the Hoogsteen faces (atoms N10 and N7) of the adeninium cations form a centrosymmetric dimer generating a characteristic R₂²(10) motif (Figs. 3 and 4). In (I), the Watson–Crick edges (atoms N1 and N10) of the cation link the anion and the neutral phenylacetic acid molecule through a three-centred hydrogen-bonding pattern (Jeffrey & Saenger, 1991). The anion and neutral phenylacetic acid molecules are interconnected by a strong O—H···O hydrogen bond (entry 6, Table 2). Thus, the combination of these N—H···O and O—H···O hydrogen bonds leads to the formation of an R³₃(12) motif. In (II), the Watson–Crick edges of the cation link the succinate anion through N—H···O hydrogen bonds, generating an R₂²(8) motif (Fig 4).

The water molecule plays a dual role as both donor and acceptor in the hydrogen-bonding interactions in (I) (Table 2). It participates in three hydrogen bonds, acting as donor to an adjacent phenylacetate anion and a symmetry-related one [Symmetry code?] via O—H···O hydrogen bonds, and as an acceptor to an adeninium cation via an intermolecular N—H···O hydrogen bond. In (II), the water molecule acts only as a donor and links the two succinate anions via O—H···O hydrogen bonding.

In (I), the combination of O—H···O, N—H···O and N—H···N hydrogen bonds involving the adeninium cations, the phenylacetate anions and the neutral phenylacetic acid molecules leads to hydrogen-bonded columns, which extend parallel to the c axis. Each column consists of chains of adeninium cations sandwiched between the hydrophilic chains of phenylacetate anions and the neutral phenylacetic acid molecules. The water molecule in turn produces a hydrogen-bonded network cavity of R⁶₆(24) motif (Fig. 3) by cross-linking the columns of adeninium cations, phenylacetate anions and neutral phenylacetic acid molecules to give hydrogen-bonded layers which lie parallel to the (010) plane. The shortest distance between the atoms N3···N3ⁱ in the cavity is 3.409 (2) Å [symmetry code: (i) -x, 1 - y + 2, -z + 1 Please check symmetry code. Should it be -x + 1, -y + 2, -z + 1 ?].

In (II), the R₂²(10) and R₂²(8) motifs are arranged alternately and form hydrogen-bonded columns in the crystal packing along the c axis (Fig. 4). Each hydrogen-bonded column is further interlinked to its adjacent glide-related columns by intermolecular N—H···O hydrogen bonds (Table 4). Water molecules connect neighbouring hydrogen-bonded columns and form a rather circular-shaped hydrogen-bonded network cavity (Fig. 4), thereby generating a characteristic R₄⁴(18) motif. These hydrogen-bonded columns aggregate as infinite two-dimensional hydrogen-bonded polymeric ribbons.

It is noteworthy that in (I), the water molecule does not have any interactions with the neutral phenylacetic acid, while in (II), it links the cation only through a weak C—H···O interaction. In both structures, weak C—H···O interactions are observed in the crystal packing. In (I), possible weak π–π stacking interactions exist between the aromatic rings of the adeninium base, with the distance between the centroids of the rings defined by atoms C4/C5/N7/C8/N9 and atoms N1/C2/N3/C4/C5/C6 at (x + 1, y, z) being 3.768 (1) Å, the interplanar spacing being 3.259 (1) Å and the centroid offset being 1.89 Å. No such π–π stacking interaction is observed in (II).

Related literature

For related literature, see: Bazzicalupi et al. (2001); Bernstein et al. (1995); Gu & Leszcynski (1999); Hillenga et al. (1995); Hingerty et al. (1981); Hodgson & Asplund (1991); Jeffrey & Saenger (1991); Langer & Huml (1978); Lippert (2005); Perun et al. (2005); Salam & Aoki (2000); Shipman et al. (2000); Sridhar & Ravikumar (2007); Voet & Rich (1970).

S2. Experimental

To obtain crystals of (I) suitable for X-ray study, adenine (0.135 g, 1 mmol) and phenylacetic acid (0.136 g, 2 mmol) were dissolved in water (10 ml) and the solution was allowed to evaporate slowly. Crystals of (II) were obtained by the slow evaporation of an equimolar solution of adenine (0.135 g) and succinic acid (0.118 g) in what solvent? (Volume?).

S3. Refinement

All N-bound H atoms, O-bound H atoms and H atoms of the water molecules were located in a difference Fourier map and their positions and isotropic displacement parameters were refined. In compound (II), the N1—H1N and O3—H3O distances were restrained with set values of 0.89 (1) and 0.86 (1) Å, respectively. Distance restraints were also applied to O1W—H1W and H1W···H2W of the water molecule [Please give details]. All other H atoms were located in a difference density map, but were positioned geometrically and included as riding atoms, with C—H distances in the range 0.93–0.98 Å, and with U_iso(H) = 1.2U_eq(C).

Computing details

For both compounds, data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. A view of the components 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. A view of the components of (II), 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. 3. A packing diagram for (I), viewed down the a axis. Dashed lines indicate O—H···O and N—H···O hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted for clarity. Only atoms involved in the hydrogen bonding are labelled. [Symmetry codes: (i) -x + 1, -y + 2, -z + 1; (ii) -x + 2, -y + 1, -z + 1; (iii) x + 1, y, z].
	Fig. 4. A packing diagram for (II), viewed down the a axis. Dashed lines indicate O—H···O and N—H···O hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted for clarity. Only atoms involved in the hydrogen bonding are labelled. [Symmetry codes: (i) x - 1, -y + 3/2, z + 1/2; (ii) -x, -y + 1, -z + 2; (iii) -x + 1, -y + 1, -z + 1].

(I) adeninium phenylacetate phenylacetic acid monohydrate

Crystal data

C5H6N5^+·C8H7O2^−·C8H8O2·H2O	Z = 2
Mr = 425.44	F(000) = 448
Triclinic, P1	Dx = 1.334 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 4.7805 (10) Å	Cell parameters from 3510 reflections
b = 10.303 (2) Å	θ = 2.2–27.6°
c = 21.678 (5) Å	µ = 0.10 mm^−1
α = 88.886 (4)°	T = 294 K
β = 87.595 (3)°	Block, colourless
γ = 83.239 (4)°	0.22 × 0.18 × 0.12 mm
V = 1059.2 (4) Å^3

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2786 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.024
Graphite monochromator	θmax = 25.0°, θmin = 0.9°
ω scans	h = −5→5
8134 measured reflections	k = −12→12
3687 independent reflections	l = −25→25

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.131	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0779P)^2 + 0.0529P] where P = (Fo^2 + 2Fc^2)/3
3687 reflections	(Δ/σ)max < 0.001
308 parameters	Δρmax = 0.22 e Å^−3
0 restraints	Δρmin = −0.14 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C2	0.1978 (4)	0.84570 (18)	0.53774 (8)	0.0404 (4)
H2	0.0397	0.8924	0.5565	0.048*
C4	0.5233 (3)	0.81580 (16)	0.46291 (8)	0.0340 (4)
C5	0.6519 (3)	0.70216 (16)	0.48834 (8)	0.0334 (4)
C6	0.5405 (4)	0.65705 (17)	0.54456 (8)	0.0352 (4)
C8	0.8818 (4)	0.73358 (18)	0.40576 (8)	0.0406 (4)
H8	1.0143	0.7243	0.3730	0.049*
N1	0.3097 (3)	0.73484 (14)	0.56691 (7)	0.0389 (4)
H1N	0.230 (4)	0.711 (2)	0.6024 (10)	0.052 (6)*
N3	0.2929 (3)	0.89189 (14)	0.48590 (7)	0.0397 (4)
N7	0.8795 (3)	0.64993 (14)	0.45204 (7)	0.0384 (4)
N9	0.6749 (3)	0.83439 (15)	0.40990 (7)	0.0387 (4)
H9N	0.658 (4)	0.897 (2)	0.3838 (9)	0.044 (5)*
N10	0.6421 (4)	0.55135 (16)	0.57442 (8)	0.0444 (4)
H10A	0.557 (4)	0.5283 (19)	0.6078 (10)	0.047 (6)*
H10B	0.795 (5)	0.5054 (19)	0.5585 (9)	0.043 (5)*
C11	−0.0881 (4)	0.7188 (2)	0.69754 (8)	0.0424 (4)
C12	−0.2588 (4)	0.6857 (2)	0.75502 (9)	0.0476 (5)
H12A	−0.4538	0.7221	0.7511	0.057*
H12B	−0.2528	0.5916	0.7594	0.057*
C13	−0.1437 (4)	0.73973 (19)	0.81138 (8)	0.0458 (5)
C14	0.0551 (5)	0.6658 (2)	0.84565 (10)	0.0610 (6)
H14	0.1170	0.5803	0.8343	0.073*
C15	0.1623 (6)	0.7167 (3)	0.89623 (12)	0.0785 (8)
H15	0.2981	0.6656	0.9184	0.094*
C16	0.0731 (6)	0.8414 (3)	0.91472 (11)	0.0776 (8)
H16	0.1456	0.8751	0.9494	0.093*
C17	−0.1247 (6)	0.9157 (3)	0.88131 (12)	0.0778 (7)
H17	−0.1867	1.0008	0.8932	0.093*
C18	−0.2323 (5)	0.8655 (2)	0.83042 (11)	0.0659 (6)
H18	−0.3674	0.9171	0.8083	0.079*
O1	−0.1423 (3)	0.82722 (14)	0.67209 (7)	0.0592 (4)
O2	0.1108 (3)	0.63633 (14)	0.67814 (6)	0.0526 (4)
C19	0.4626 (4)	0.35704 (18)	0.72295 (8)	0.0437 (5)
C20	0.5603 (5)	0.2422 (2)	0.76325 (10)	0.0629 (6)
H20A	0.4712	0.1675	0.7508	0.075*
H20B	0.7621	0.2210	0.7564	0.075*
C21	0.4985 (4)	0.2629 (2)	0.83090 (9)	0.0526 (5)
C22	0.3188 (6)	0.1912 (3)	0.86351 (11)	0.0738 (7)
H22	0.2313	0.1293	0.8432	0.089*
C23	0.2645 (7)	0.2085 (4)	0.92544 (14)	0.0968 (10)
H23	0.1410	0.1583	0.9465	0.116*
C24	0.3873 (7)	0.2971 (3)	0.95631 (13)	0.0894 (9)
H24	0.3493	0.3082	0.9984	0.107*
C25	0.5684 (7)	0.3706 (3)	0.92514 (14)	0.0947 (9)
H25	0.6528	0.4329	0.9459	0.114*
C26	0.6264 (6)	0.3520 (3)	0.86221 (12)	0.0808 (8)
H26	0.7534	0.4007	0.8413	0.097*
O3	0.2222 (3)	0.42029 (17)	0.73987 (7)	0.0680 (5)
H3O	0.182 (6)	0.497 (3)	0.7126 (14)	0.105 (10)*
O4	0.5954 (3)	0.38617 (15)	0.67788 (6)	0.0632 (4)
O1W	0.3449 (4)	0.97577 (15)	0.67927 (7)	0.0561 (4)
H1W	0.506 (7)	0.920 (3)	0.6770 (12)	0.090 (9)*
H2W	0.206 (6)	0.932 (3)	0.6823 (12)	0.090 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C2	0.0352 (10)	0.0419 (10)	0.0432 (10)	−0.0001 (8)	−0.0016 (8)	−0.0051 (8)
C4	0.0340 (9)	0.0329 (9)	0.0357 (9)	−0.0053 (7)	−0.0055 (7)	0.0007 (7)
C5	0.0323 (9)	0.0339 (9)	0.0341 (9)	−0.0025 (7)	−0.0048 (7)	−0.0002 (7)
C6	0.0354 (9)	0.0357 (9)	0.0356 (9)	−0.0068 (7)	−0.0066 (7)	−0.0011 (7)
C8	0.0406 (10)	0.0428 (10)	0.0369 (10)	0.0003 (8)	0.0011 (8)	0.0016 (8)
N1	0.0379 (8)	0.0424 (9)	0.0357 (8)	−0.0026 (7)	0.0001 (7)	0.0013 (7)
N3	0.0382 (8)	0.0365 (8)	0.0435 (9)	−0.0003 (7)	−0.0031 (7)	0.0005 (7)
N7	0.0384 (8)	0.0372 (8)	0.0379 (8)	0.0014 (6)	−0.0003 (6)	0.0024 (6)
N9	0.0445 (9)	0.0343 (8)	0.0362 (8)	−0.0013 (7)	−0.0029 (7)	0.0080 (7)
N10	0.0499 (10)	0.0420 (9)	0.0389 (9)	0.0018 (8)	0.0017 (8)	0.0105 (7)
C11	0.0359 (10)	0.0513 (12)	0.0406 (10)	−0.0076 (9)	−0.0050 (8)	0.0047 (9)
C12	0.0407 (11)	0.0546 (12)	0.0483 (11)	−0.0115 (9)	0.0012 (9)	0.0080 (9)
C13	0.0404 (10)	0.0528 (12)	0.0438 (11)	−0.0097 (9)	0.0096 (8)	0.0089 (9)
C14	0.0625 (14)	0.0647 (14)	0.0540 (13)	0.0006 (11)	−0.0037 (11)	0.0022 (11)
C15	0.0772 (18)	0.098 (2)	0.0592 (15)	−0.0040 (16)	−0.0165 (13)	0.0076 (14)
C16	0.0850 (19)	0.101 (2)	0.0518 (14)	−0.0292 (17)	−0.0011 (13)	−0.0079 (14)
C17	0.092 (2)	0.0694 (17)	0.0730 (17)	−0.0126 (15)	0.0016 (15)	−0.0126 (13)
C18	0.0682 (15)	0.0618 (15)	0.0665 (15)	−0.0023 (12)	−0.0051 (12)	0.0022 (12)
O1	0.0556 (9)	0.0555 (9)	0.0627 (9)	0.0026 (7)	0.0080 (7)	0.0199 (7)
O2	0.0498 (8)	0.0575 (9)	0.0465 (8)	0.0066 (7)	0.0035 (6)	0.0093 (6)
C19	0.0485 (11)	0.0410 (11)	0.0409 (11)	−0.0038 (9)	0.0004 (9)	−0.0001 (8)
C20	0.0754 (16)	0.0509 (13)	0.0571 (13)	0.0092 (11)	0.0091 (11)	0.0106 (10)
C21	0.0565 (13)	0.0459 (11)	0.0520 (12)	0.0060 (10)	−0.0025 (10)	0.0142 (9)
C22	0.0819 (18)	0.0776 (17)	0.0627 (15)	−0.0178 (14)	0.0096 (13)	0.0030 (12)
C23	0.100 (2)	0.123 (3)	0.0684 (18)	−0.026 (2)	0.0203 (16)	0.0091 (17)
C24	0.099 (2)	0.112 (2)	0.0534 (15)	0.0032 (19)	−0.0030 (15)	0.0038 (16)
C25	0.118 (3)	0.091 (2)	0.078 (2)	−0.0175 (19)	−0.0341 (18)	−0.0041 (16)
C26	0.097 (2)	0.0762 (18)	0.0723 (17)	−0.0238 (15)	−0.0107 (15)	0.0170 (14)
O3	0.0602 (10)	0.0692 (11)	0.0671 (10)	0.0132 (8)	0.0166 (8)	0.0247 (8)
O4	0.0677 (10)	0.0647 (10)	0.0504 (9)	0.0116 (8)	0.0148 (7)	0.0164 (7)
O1W	0.0574 (10)	0.0455 (9)	0.0640 (10)	−0.0034 (8)	−0.0022 (8)	0.0164 (7)

Geometric parameters (Å, º)

C2—N3	1.297 (2)	C15—C16	1.368 (4)
C2—N1	1.359 (2)	C15—H15	0.9300
C2—H2	0.9300	C16—C17	1.367 (4)
C4—N9	1.355 (2)	C16—H16	0.9300
C4—N3	1.357 (2)	C17—C18	1.372 (3)
C4—C5	1.374 (2)	C17—H17	0.9300
C5—N7	1.378 (2)	C18—H18	0.9300
C5—C6	1.403 (2)	C19—O4	1.196 (2)
C6—N10	1.310 (2)	C19—O3	1.295 (2)
C6—N1	1.363 (2)	C19—C20	1.498 (3)
C8—N7	1.310 (2)	C20—C21	1.498 (3)
C8—N9	1.349 (2)	C20—H20A	0.9700
C8—H8	0.9300	C20—H20B	0.9700
N1—H1N	0.89 (2)	C21—C22	1.364 (3)
N9—H9N	0.85 (2)	C21—C26	1.368 (3)
N10—H10A	0.86 (2)	C22—C23	1.368 (4)
N10—H10B	0.89 (2)	C22—H22	0.9300
C11—O1	1.241 (2)	C23—C24	1.345 (4)
C11—O2	1.262 (2)	C23—H23	0.9300
C11—C12	1.516 (3)	C24—C25	1.365 (4)
C12—C13	1.503 (3)	C24—H24	0.9300
C12—H12A	0.9700	C25—C26	1.393 (4)
C12—H12B	0.9700	C25—H25	0.9300
C13—C14	1.379 (3)	C26—H26	0.9300
C13—C18	1.380 (3)	O3—H3O	0.99 (3)
C14—C15	1.369 (3)	O1W—H1W	0.91 (3)
C14—H14	0.9300	O1W—H2W	0.85 (3)
N3—C2—N1	125.52 (17)	C16—C15—C14	121.1 (3)
N3—C2—H2	117.2	C16—C15—H15	119.5
N1—C2—H2	117.2	C14—C15—H15	119.5
N9—C4—N3	127.75 (15)	C17—C16—C15	118.8 (3)
N9—C4—C5	105.04 (15)	C17—C16—H16	120.6
N3—C4—C5	127.21 (15)	C15—C16—H16	120.6
C4—C5—N7	111.48 (15)	C16—C17—C18	120.5 (3)
C4—C5—C6	118.34 (16)	C16—C17—H17	119.8
N7—C5—C6	130.17 (16)	C18—C17—H17	119.8
N10—C6—N1	121.34 (17)	C17—C18—C13	121.2 (2)
N10—C6—C5	125.12 (17)	C17—C18—H18	119.4
N1—C6—C5	113.55 (15)	C13—C18—H18	119.4
N7—C8—N9	113.96 (16)	O4—C19—O3	122.76 (18)
N7—C8—H8	123.0	O4—C19—C20	122.11 (18)
N9—C8—H8	123.0	O3—C19—C20	115.11 (17)
C2—N1—C6	123.41 (16)	C21—C20—C19	114.53 (18)
C2—N1—H1N	119.0 (14)	C21—C20—H20A	108.6
C6—N1—H1N	117.6 (14)	C19—C20—H20A	108.6
C2—N3—C4	111.97 (15)	C21—C20—H20B	108.6
C8—N7—C5	102.76 (15)	C19—C20—H20B	108.6
C8—N9—C4	106.76 (15)	H20A—C20—H20B	107.6
C8—N9—H9N	123.1 (14)	C22—C21—C26	117.9 (2)
C4—N9—H9N	130.1 (13)	C22—C21—C20	121.2 (2)
C6—N10—H10A	119.5 (14)	C26—C21—C20	120.9 (2)
C6—N10—H10B	117.8 (13)	C21—C22—C23	121.4 (3)
H10A—N10—H10B	122.6 (19)	C21—C22—H22	119.3
O1—C11—O2	121.99 (17)	C23—C22—H22	119.3
O1—C11—C12	119.20 (17)	C24—C23—C22	120.9 (3)
O2—C11—C12	118.77 (17)	C24—C23—H23	119.5
C13—C12—C11	110.59 (15)	C22—C23—H23	119.5
C13—C12—H12A	109.5	C23—C24—C25	119.3 (3)
C11—C12—H12A	109.5	C23—C24—H24	120.4
C13—C12—H12B	109.5	C25—C24—H24	120.4
C11—C12—H12B	109.5	C24—C25—C26	119.9 (3)
H12A—C12—H12B	108.1	C24—C25—H25	120.1
C14—C13—C18	117.7 (2)	C26—C25—H25	120.1
C14—C13—C12	121.24 (19)	C21—C26—C25	120.6 (3)
C18—C13—C12	121.08 (19)	C21—C26—H26	119.7
C15—C14—C13	120.8 (2)	C25—C26—H26	119.7
C15—C14—H14	119.6	C19—O3—H3O	109.4 (18)
C13—C14—H14	119.6	H1W—O1W—H2W	108 (3)
N9—C4—C5—N7	−0.17 (19)	C11—C12—C13—C14	−92.2 (2)
N3—C4—C5—N7	179.34 (16)	C11—C12—C13—C18	87.4 (2)
N9—C4—C5—C6	179.92 (15)	C18—C13—C14—C15	−0.8 (3)
N3—C4—C5—C6	−0.6 (3)	C12—C13—C14—C15	178.8 (2)
C4—C5—C6—N10	−179.32 (16)	C13—C14—C15—C16	0.9 (4)
N7—C5—C6—N10	0.8 (3)	C14—C15—C16—C17	−0.6 (4)
C4—C5—C6—N1	0.4 (2)	C15—C16—C17—C18	0.3 (4)
N7—C5—C6—N1	−179.49 (16)	C16—C17—C18—C13	−0.3 (4)
N3—C2—N1—C6	−0.1 (3)	C14—C13—C18—C17	0.6 (3)
N10—C6—N1—C2	179.63 (16)	C12—C13—C18—C17	−179.1 (2)
C5—C6—N1—C2	−0.1 (2)	O4—C19—C20—C21	142.8 (2)
N1—C2—N3—C4	0.0 (3)	O3—C19—C20—C21	−38.5 (3)
N9—C4—N3—C2	179.74 (17)	C19—C20—C21—C22	115.4 (2)
C5—C4—N3—C2	0.3 (3)	C19—C20—C21—C26	−66.2 (3)
N9—C8—N7—C5	0.1 (2)	C26—C21—C22—C23	0.8 (4)
C4—C5—N7—C8	0.04 (19)	C20—C21—C22—C23	179.1 (2)
C6—C5—N7—C8	179.94 (18)	C21—C22—C23—C24	0.0 (5)
N7—C8—N9—C4	−0.2 (2)	C22—C23—C24—C25	0.0 (5)
N3—C4—N9—C8	−179.28 (17)	C23—C24—C25—C26	−0.8 (5)
C5—C4—N9—C8	0.22 (18)	C22—C21—C26—C25	−1.5 (4)
O1—C11—C12—C13	−83.4 (2)	C20—C21—C26—C25	−179.9 (2)
O2—C11—C12—C13	94.4 (2)	C24—C25—C26—C21	1.6 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2	0.89 (2)	1.89 (2)	2.773 (2)	170 (2)
N1—H1N···O1	0.89 (2)	2.49 (2)	3.156 (2)	131.8 (17)
N9—H9N···O1W^i	0.85 (2)	1.88 (2)	2.720 (2)	173.4 (19)
N10—H10A···O4	0.86 (2)	2.09 (2)	2.806 (2)	140.9 (18)
N10—H10B···N7^ii	0.89 (2)	2.10 (2)	2.946 (2)	158.6 (17)
O3—H3O···O2	0.99 (3)	1.61 (3)	2.587 (2)	171 (3)
O1W—H2W···O1	0.85 (3)	2.11 (3)	2.945 (2)	170 (3)
O1W—H1W···O1^iii	0.91 (3)	1.83 (3)	2.733 (2)	172 (3)
C8—H8···O4^ii	0.93	2.32	3.168 (3)	152

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

(II) adeninium 3-carboxypropionate monohydrate

Crystal data

C5H6N5^+·C4H3O4^−·H2O	F(000) = 560
Mr = 269.23	Dx = 1.492 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8119 reflections
a = 9.539 (3) Å	θ = 2.5–28.0°
b = 17.149 (6) Å	µ = 0.12 mm^−1
c = 7.450 (3) Å	T = 294 K
β = 100.503 (5)°	Needle, colourless
V = 1198.3 (7) Å^3	0.25 × 0.15 × 0.07 mm
Z = 4

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2112 independent reflections
Radiation source: fine-focus sealed tube	1934 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
ω scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan (SABABS; Bruker, 2001)	h = −11→11
Tmin = 0.97, Tmax = 0.98	k = −20→20
10914 measured reflections	l = −8→8

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)] = 0.044	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.124	w = 1/[σ^2(Fo^2) + (0.0786P)^2 + 0.1186P] where P = (Fo^2 + 2Fc^2)/3
S = 1.16	(Δ/σ)max < 0.001
2112 reflections	Δρmax = 0.21 e Å^−3
197 parameters	Δρmin = −0.24 e Å^−3
4 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.014 (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
C2	0.30508 (17)	0.71386 (10)	0.8304 (2)	0.0553 (4)
H2	0.3819	0.7387	0.7940	0.066*
C4	0.09829 (16)	0.71472 (9)	0.92531 (18)	0.0451 (4)
C5	0.09084 (14)	0.63397 (8)	0.93719 (18)	0.0429 (3)
C6	0.20234 (15)	0.58941 (8)	0.88586 (18)	0.0434 (3)
C8	−0.09487 (17)	0.67875 (9)	1.0206 (2)	0.0530 (4)
H8	−0.1811	0.6823	1.0617	0.064*
N1	0.30705 (13)	0.63444 (8)	0.83389 (17)	0.0506 (3)
H1N	0.3853 (15)	0.6137 (12)	0.797 (2)	0.073 (6)*
N3	0.20488 (15)	0.75821 (8)	0.87348 (19)	0.0541 (4)
N7	−0.03211 (13)	0.61135 (7)	0.99833 (17)	0.0499 (3)
N9	−0.02190 (14)	0.74226 (8)	0.97801 (19)	0.0508 (3)
H9N	−0.043 (2)	0.7913 (16)	0.982 (3)	0.078 (6)*
N10	0.21206 (15)	0.51274 (7)	0.88423 (18)	0.0514 (3)
H10A	0.292 (2)	0.4910 (14)	0.854 (3)	0.081 (6)*
H10B	0.139 (2)	0.4825 (11)	0.919 (2)	0.061 (5)*
C11	0.56012 (16)	0.49986 (9)	0.7303 (2)	0.0493 (4)
C12	0.68762 (16)	0.46488 (9)	0.6682 (2)	0.0484 (4)
H12	0.6942	0.4109	0.6776	0.058*
C13	0.79349 (16)	0.49941 (9)	0.6012 (2)	0.0487 (4)
H13	0.8625	0.4653	0.5741	0.058*
C14	0.81954 (16)	0.58309 (8)	0.5628 (2)	0.0490 (4)
O1	0.54367 (12)	0.57392 (7)	0.72622 (18)	0.0643 (4)
O2	0.47499 (13)	0.45476 (7)	0.78448 (17)	0.0641 (4)
O3	0.73222 (12)	0.63797 (6)	0.59543 (17)	0.0601 (3)
H3O	0.6612 (18)	0.6208 (13)	0.646 (3)	0.082 (6)*
O4	0.92546 (14)	0.59986 (7)	0.4990 (2)	0.0721 (4)
O1W	0.5899 (2)	0.70336 (11)	0.1990 (3)	0.1047 (6)
H1W	0.539 (4)	0.6619 (16)	0.155 (4)	0.23 (2)*
H2W	0.6375	0.7020	0.3096	0.098*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C2	0.0496 (8)	0.0480 (9)	0.0735 (10)	−0.0027 (7)	0.0252 (7)	0.0074 (7)
C4	0.0428 (8)	0.0422 (8)	0.0521 (7)	0.0039 (6)	0.0133 (6)	0.0016 (6)
C5	0.0398 (7)	0.0405 (8)	0.0509 (7)	−0.0001 (6)	0.0148 (5)	0.0014 (5)
C6	0.0411 (7)	0.0414 (8)	0.0504 (7)	0.0008 (5)	0.0152 (5)	0.0012 (5)
C8	0.0444 (8)	0.0491 (9)	0.0699 (9)	0.0028 (6)	0.0222 (7)	0.0006 (7)
N1	0.0447 (7)	0.0463 (7)	0.0664 (8)	0.0016 (5)	0.0250 (6)	0.0039 (5)
N3	0.0522 (7)	0.0426 (7)	0.0718 (8)	−0.0008 (5)	0.0228 (6)	0.0056 (5)
N7	0.0418 (7)	0.0453 (7)	0.0673 (7)	0.0007 (5)	0.0219 (5)	0.0010 (5)
N9	0.0472 (7)	0.0407 (7)	0.0680 (8)	0.0070 (5)	0.0196 (6)	0.0008 (5)
N10	0.0475 (7)	0.0390 (7)	0.0733 (8)	0.0020 (5)	0.0263 (6)	−0.0004 (5)
C11	0.0452 (8)	0.0478 (9)	0.0584 (8)	0.0009 (6)	0.0186 (6)	0.0012 (6)
C12	0.0507 (8)	0.0354 (7)	0.0625 (8)	0.0043 (6)	0.0191 (7)	0.0022 (6)
C13	0.0466 (8)	0.0389 (7)	0.0649 (8)	0.0059 (6)	0.0215 (6)	−0.0027 (6)
C14	0.0464 (8)	0.0399 (8)	0.0649 (8)	−0.0008 (6)	0.0211 (6)	−0.0046 (6)
O1	0.0554 (7)	0.0455 (7)	0.1020 (9)	0.0072 (5)	0.0410 (6)	0.0024 (5)
O2	0.0581 (7)	0.0524 (7)	0.0905 (8)	−0.0028 (5)	0.0367 (6)	0.0046 (5)
O3	0.0559 (7)	0.0361 (6)	0.0964 (9)	0.0025 (5)	0.0354 (6)	−0.0006 (5)
O4	0.0662 (8)	0.0469 (6)	0.1172 (10)	−0.0053 (5)	0.0541 (7)	−0.0034 (6)
O1W	0.0806 (11)	0.0699 (10)	0.1677 (17)	−0.0015 (8)	0.0334 (10)	0.0091 (11)

Geometric parameters (Å, º)

C2—N3	1.307 (2)	N10—H10A	0.91 (2)
C2—N1	1.362 (2)	N10—H10B	0.943 (19)
C2—H2	0.9300	C11—O2	1.2410 (19)
C4—N9	1.362 (2)	C11—O1	1.279 (2)
C4—N3	1.372 (2)	C11—C12	1.503 (2)
C4—C5	1.390 (2)	C12—C13	1.343 (2)
C5—N7	1.3886 (18)	C12—H12	0.9300
C5—C6	1.418 (2)	C13—C14	1.493 (2)
C6—N10	1.318 (2)	C13—H13	0.9300
C6—N1	1.3730 (19)	C14—O4	1.2266 (19)
C8—N7	1.326 (2)	C14—O3	1.3087 (18)
C8—N9	1.361 (2)	O3—H3O	0.883 (10)
C8—H8	0.9300	O1W—H1W	0.89 (3)
N1—H1N	0.914 (10)	O1W—H2W	0.87
N9—H9N	0.87 (3)
N3—C2—N1	125.83 (14)	C8—N9—C4	106.44 (13)
N3—C2—H2	117.1	C8—N9—H9N	129.6 (16)
N1—C2—H2	117.1	C4—N9—H9N	123.9 (16)
N9—C4—N3	126.76 (14)	C6—N10—H10A	118.3 (15)
N9—C4—C5	105.75 (13)	C6—N10—H10B	119.3 (12)
N3—C4—C5	127.48 (13)	H10A—N10—H10B	122.3 (19)
N7—C5—C4	110.81 (12)	O2—C11—O1	122.79 (14)
N7—C5—C6	131.15 (13)	O2—C11—C12	117.76 (14)
C4—C5—C6	118.04 (12)	O1—C11—C12	119.45 (13)
N10—C6—N1	120.16 (13)	C13—C12—C11	130.10 (14)
N10—C6—C5	126.69 (13)	C13—C12—H12	115.0
N1—C6—C5	113.15 (13)	C11—C12—H12	115.0
N7—C8—N9	113.99 (14)	C12—C13—C14	131.14 (14)
N7—C8—H8	123.0	C12—C13—H13	114.4
N9—C8—H8	123.0	C14—C13—H13	114.4
C2—N1—C6	124.03 (13)	O4—C14—O3	120.04 (14)
C2—N1—H1N	113.1 (14)	O4—C14—C13	118.51 (13)
C6—N1—H1N	122.9 (14)	O3—C14—C13	121.45 (13)
C2—N3—C4	111.45 (13)	C14—O3—H3O	113.8 (16)
C8—N7—C5	103.01 (12)	H1W—O1W—H2W	119
N9—C4—C5—N7	−0.55 (16)	C5—C4—N3—C2	1.1 (2)
N3—C4—C5—N7	178.76 (14)	N9—C8—N7—C5	0.20 (18)
N9—C4—C5—C6	178.68 (12)	C4—C5—N7—C8	0.23 (16)
N3—C4—C5—C6	−2.0 (2)	C6—C5—N7—C8	−178.87 (15)
N7—C5—C6—N10	0.6 (2)	N7—C8—N9—C4	−0.55 (19)
C4—C5—C6—N10	−178.43 (14)	N3—C4—N9—C8	−178.68 (14)
N7—C5—C6—N1	−179.49 (13)	C5—C4—N9—C8	0.64 (16)
C4—C5—C6—N1	1.46 (18)	O2—C11—C12—C13	178.74 (15)
N3—C2—N1—C6	−0.6 (2)	O1—C11—C12—C13	−1.5 (2)
N10—C6—N1—C2	179.56 (14)	C11—C12—C13—C14	−1.2 (3)
C5—C6—N1—C2	−0.3 (2)	C12—C13—C14—O4	−179.32 (17)
N1—C2—N3—C4	0.3 (2)	C12—C13—C14—O3	0.6 (3)
N9—C4—N3—C2	−179.76 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O1	0.91 (1)	1.82 (2)	2.734 (2)	179 (2)
N9—H9N···O4^i	0.87 (3)	1.90 (3)	2.763 (2)	176 (2)
N10—H10A···O2	0.91 (2)	2.01 (2)	2.917 (2)	174 (2)
N10—H10B···N7^ii	0.943 (19)	2.06 (2)	2.964 (2)	161 (2)
O3—H3O···O1	0.88 (1)	1.58 (1)	2.4557 (17)	169 (2)
O1W—H1W···O2^iii	0.89 (3)	2.06 (2)	2.789 (2)	138 (2)
O1W—H2W···O3	0.87	2.42	3.219 (3)	154
C2—H2···O1W^iv	0.93	2.44	3.365 (3)	177
C13—H13···O4^v	0.93	2.46	3.372 (2)	168

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