Infinite ladder-like chains organized into a three-dimensional zigzag supramolecular architecture in 9-deazahypoxanthine

Article abstract of DOI:10.1107/S0108270112050767

The asymmetric unit of the title compound, C6H5N3O, consists of discrete molecules of 9-deazahypoxanthine [systematic name: 3H-pyrrolo[3,2-d]pyrimidin- 4(5H)-one]. The structure displays N - H ?O hydrogen bonding, connecting the molecules into centrosymmetric dimers. These dimers are then connected by N - H ?N hydrogen bonds into a ladder-like chain along the c axis. The secondary structure is stabilized by weak noncovalent contacts of the C - H ?O and C - H ?C types, as well as by π- π stacking interactions, which organize the structure into a zigzag architecture.

Full text of DOI:10.1107/S0108270112050767

organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
9-deazahypoxanthine derivatives has been incessant and more
derivatives have been prepared and tested as antiproliferative
(Otmar et al., 2004) or antidiabetic (Sutton et al., 2012) agents.
ISSN 0108-2701
Infinite ladder-like chains organized
into a three-dimensional zigzag
supramolecular architecture in
9-deazahypoxanthine
Even though (I) has long been known and is well char-
acterized, a search of the Cambridge Structural Database
(Version 5.33, August 2012 update; Allen, 2002) gave 17
structures involving the 9-deazahypoxanthine group and none
of these showed the structural arrangement of the unsub-
stituted title molecule. All the data deposited so far describe
the structures of variously mono-, bi- and trisubstituted
9-deazahypoxanthine derivatives exhibiting different biolo-
gical properties. For many of these derivatives, (I) served as a
synthetic precursor. For example, 6-chloro-9-deazapurine is
easily available from 9-deazahypoxanthine, and it may then
serve as a perfect precursor for the preparation of 9-deaza-
analogues of C6-substituted purines, such as the potent cyclin-
ˇ
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Radka Novotna and Zdenek Travnıcek*
Regional Centre of Advanced Technologies and Materials, Department of Inorganic
´
Chemistry, Faculty of Science, Palacky University, 17. listopadu 12, CZ-771 46
Olomouc, Czech Republic
Correspondence e-mail: zdenek.travnicek@upol.cz
Received 12 December 2012
Accepted 13 December 2012
Online 5 January 2013
The asymmetric unit of the title compound, C6H5N3O, consists
of discrete molecules of 9-deazahypoxanthine [systematic
name: 3H-pyrrolo[3,2-d]pyrimidin-4(5H)-one]. The structure
displays N—Hꢀ ꢀ ꢀO hydrogen bonding, connecting the mol-
ecules into centrosymmetric dimers. These dimers are then
connected by N—Hꢀ ꢀ ꢀN hydrogen bonds into a ladder-like
chain along the c axis. The secondary structure is stabilized by
weak noncovalent contacts of the C—Hꢀ ꢀ ꢀO and C—Hꢀ ꢀ ꢀC
types, as well as by ꢀ–ꢀ stacking interactions, which organize
the structure into a zigzag architecture.
ˇ
dependent kinase inhibitor olomoucine (Capek et al., 2003). It
is well established that knowledge of the molecular structure
and crystal packing of a compound provides the necessary
information for defining possible structure–property rela-
tionships, involving different polymorphs with varying
physical and chemical properties important in pharmacology,
or for the identification of possible coordination sites when the
compound acts as a ligand in a metal complex. Therefore, in
connection with the medicinal potential of 9-deazahypox-
anthine derivatives, the constant search for more potent
analogues and their potential use as ligands in the prepara-
tions of biologically active transition metal complexes, the
effort to provide a thorough structural description arising
from X-ray structure determination accompanied by a
combination of analytical methods such as multinuclear NMR
spectroscopy or mass spectrometry is unambiguously justified.
In this work, we report not only the detailed structural
determination of 9-deazahypoxanthine, (I), in the solid state
by single-crystal X-ray analysis, but also a thorough char-
acterization of this compound by a wide spectrum of other
methods.
Before the isolated title compound was subjected to crys-
tallization attempts, it was fully characterized after prepara-
tion in order to confirm its identity and chemical purity. The
techniques used for the study of the composition of (I)
involved elemental analysis and spectroscopic (IR, MS and
NMR) methods. The NMR spectroscopic measurements
unambiguously confirmed the composition of (I). It should be
pointed out that full interpretations of the 1H, 13C and
15N NMR spectra of (I) have not been reported in the
literature thus far.
Comment
3,5-Dihydropyrrolo[3,2-d]pyrimidines, and in particular the
title compound, 9-deazahypoxanthine, (I), have become of
great interest because of the potential pharmaceutical use of
their derivatives (Montgomery et al., 1993; Bzowska et al.,
2000). C9-Substituted 9-deazahypoxanthines (immucillins) are
powerful inhibitors of purine nucleoside phosphorylase
(PNP), which reversibly catalyses the cleavage of purine
nucleosides to the corresponding free bases. The activity of
this enzyme is most probably required for normal human
T-cell proliferation, and therefore PNP inhibitors represent a
novel class of potential selective immunosuppressive agents
and may be useful for the treatment of autoimmune disorders,
such as psoriasis and rheumatoid arthritis, and other T-cell
proliferative disorders, such as organ-transplant rejection and
adult T-cell leukaemia (Bantia et al., 2001). Moreover, two
members of the immucillin family, viz. immucillin-H [BCX-
1777, 1-(9-deazahypoxanthin)-1,4-dideoxy-1,4-imino-d-ribitol)]
and DADMe-immucillin-H (BCX-4208, 7-{[(3R,4R)-3-hy-
droxy-4-(hydroxymethyl)pyrrolidin-1-yl]methyl}-1,5-dihydro-
pyrrolo[3,2-d]pyrimidin-4-one), are currently in human clin-
ical trials for the treatment of T- and B-cell cancers and
autoimmune diseases (Clinch et al., 2009). Research on
The molecular structure of (I) consists of discrete molecules
of 9-deazahypoxanthine (Fig. 1). The molecule contains nearly
coplanar pyrimidine and pyrrole rings [dihedral angle =
158 # 2013 International Union of Crystallography
doi:10.1107/S0108270112050767
Acta Cryst. (2013). C69, 158–161

organic compounds
connection with the protonation at atom N7 in (I), in contrast
with hypoxanthine, where the N9 site is primarily protonated.
While the differences in the angles at N7 are conclusively
significant, the substitution of N9 in hypoxanthine by C9 in (I)
does not bring about a significant difference in the angle at
position 9. On the other hand, the bond angles in (I) are
comparable with those reported for a monosubstituted deri-
vative of (I), namely 9-deazainosine monohydrate [9-(2-hy-
droxyethoxymethyl)-9-deazahypoxanthine monohydrate; Otter
et al., 1992]. For a comparison of selected bond angles, see
Table 1.
The crystal structure consists of the molecules of (I) orga-
nized into one-dimensional ladder-like chains along the c axis
(Fig. 2) by hydrogen bonding of moderate strength. Two
heteroaromatic amine groups are involved in the formation of
two main supramolecular ring synthons (Bernstein et al.,
1995): (a) a centrosymmetric amide-like R22(8) ring involving
the donor N1—H group and atom O1 as an acceptor and (b)
an asymmetric R22(8) ring involving N7—H and C2—H donors,
and atoms O1 and N3 as acceptors, respectively. These
hydrogen bonds provided by the heteroaromatic amine groups
are of different strengths, as can be seen from the donor–
acceptor distances (Table 2). This difference in donor–
acceptor distance can be rationalized on the basis of the
different types of hydrogen-bond acceptors, where the lower
electronegativity of nitrogen with respect to oxygen deter-
mines the different qualities of the noncovalent contacts. The
C2—H2ꢀ ꢀ ꢀO1iii contact is rather long in comparison with the
aforementioned hydrogen bonds (Table 2), but its distance
classifies it in the group of very short C—Hꢀ ꢀ ꢀO hydrogen
bonds (Desiraju & Steiner, 2001).
Figure 1
The molecular structure of (I), showing the atom-numbering scheme.
Displacement ellipsoids are drawn at the 50% probability level.
0.70 (7)ꢁ]. Both rings, i.e. pyrimidine as well as pyrrole, deviate
from planarity (Nardelli, 1995), the maximum deviations from
˚
the mean planes being 0.004 (2) and 0.005 (2) A for atom C4
in the case of the pyrimidine and pyrrole rings, respectively.
While the molecule is essentially planar, with the maximum
˚
deviation being 0.014 (2) A for atom C9, statistically, it devi-
ates from planarity significantly (Nardelli, 1995).
The molecule of (I) can formally be derived from the
hypoxanthine skeleton by substituting atom N9 for a C atom.
Two polymorphs of hypoxanthine have been published so far,
viz. the triclinic form (Schmalle et al., 1988) and the mono-
clinic form (Yang & Xie, 2007). Comparing the structural
parameters and focusing on bond angles, the most significant
differences would be expected in the vicinity of the substituted
C9/N9 atoms, as well as at the N7 site, more specifically in the
case of the C5—N7—C8 and C4—C9—C8 angles in (I), and
the C5—N7—C8 and C4—N9—C8 angles in hypoxanthine.
The expected changes can be explained not only on the basis
of the presence of different atoms in the 9-position, but also in
The individual one-dimensional ladder-like chains are
interconnected by ꢀ–ꢀ stacking interactions, thus forming a
Figure 2
(a) Aview of (I) along the a axis, showing the N—Hꢀ ꢀ ꢀO, N—Hꢀ ꢀ ꢀN and C—Hꢀ ꢀ ꢀO hydrogen bonding (dashed lines). (b) Aview of the one-dimensional
ladder-like chain along the c axis, showing its planarity. [Symmetry codes: (i) ꢃx + 2, ꢃy, ꢃz + 1; (ii) x, y, z + 1; (iii) x, y, z ꢃ 1.]
ꢂ
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Acta Cryst. (2013). C69, 158–161
Novotna and Travnıcek C6H5N3O 159

organic compounds
Figure 3
Part of the crystal structure of (I), showing the formation of layers of ladder-like chains stacked by ꢀ–ꢀ interactions, with a distance d between
˚
neighbouring layers of 3.193 A, and the formation of the zigzag supramolecular architecture along the c axis. Dotted lines indicate intermolecular
interactions.
ratio of 1:31 used by Kamath et al. (2009)] enabled direct isolation of
methyl 4-oxo-4,5-dihydro-3H-pyrrolo[3,2-d]pyrimidine-7-carboxyl-
ate from the reaction solution. This intermediate was purified by
recrystallization from acetic acid. The final reaction step was used
without any modifications to achieve (I) as a beige solid. Colourless
crystals suitable for X-ray studies were obtained by slow evaporation
from a water solution.
two-dimensional arrangement. The distance between the
planes fitted through the non-H atoms of ten molecules in
˚
each plane forming the one-dimensional chain is d = 3.193 A
(Fig. 3). The closest Cꢀ ꢀ ꢀC contact is between atoms C9 and
iv
˚
C2 [Cꢀ ꢀ ꢀC = 3.267 (3) A; symmetry code: (iv) x ꢃ 1, y, z]. The
distance between these best-fit planes is significantly shorter
than that between the individual aromatic rings, which are
thus not placed directly above one another, as demonstrated
IR (ꢁmax, cmꢃ1): 3265 (N—H)ar, 3151, 3103, 3021 (C—H)ar, 1663
1
. . .
. . .
(C O), 1595, 1542, 1516, 1483 (C C)ring and (C N)ring. H NMR
(DMF-d7, TMS, 298 K): ꢂ 12.15 (bs, 1H, HN7), 11.82 (bs, 1H, HN1),
7.93 (s, 1H, HC2), 7.49 (d, J = 2.6 Hz, 1H, HC8), 6.43 (d, J = 2.8 Hz, 1H,
HC9). 13C NMR (DMF-d7, TMS, 298 K): ꢂ 154.1 (C6), 145.4 (C4),
141.9 (C2), 127.5 (C8), 118.6 (C5), 103.4 (C9). 15N NMR (DMF-d7,
relative to DMF, 298 K): ꢂ 140.42 [d, J = 101.2 Hz, 12.15, HN7; s, 7.49,
HC8; s, 6.43, HC9 (N7)], 166.6 [s, 47.93, HC2 (N1)], 236.47 [d, J =
10.7 Hz, 7.93, HC2 (N3)]. ESI+MS: m/z 136.1 [M + H]+ (calculated =
136.1), 158.1 [M + Na]+ (calculated = 158.1). Analysis calculated for
C6H5N3O: C 53.33, H 3.73, N 31.10%; found: C 53.46, H 3.70,
N 31.44%.
by the centroid–centroid distance [Cg1ꢀ ꢀ ꢀCg1iv
=
4.8315 (12) A, where Cg1 is the centroid of the non-H atoms
of (I)]. In other words, neighbouring layers are shifted by
˚
˚
3.626 A.
Additional weak noncovalent contacts are also present
within the crystal structure of (I), viz. C9—H9ꢀ ꢀ ꢀC8v [Cꢀ ꢀ ꢀC =
1
2
1
2
1
2
˚
3.557 (3) A; symmetry code: (v) x ꢃ , ꢃy + , z ꢃ ]. This
connects the individual infinite ladder-like chains, which
results in the organization of the crystal structure into a three-
dimensional zigzag architecture, as viewed along the c axis
(Fig. 3). The least-squares planes of the molecules in the one-
dimensional ladder-like chains organized into the zigzag
structure are nearly perpendicular; the dihedral angle is about
86ꢁ.
Crystal data
3
˚
C6H5N3O
Mr = 135.13
V = 593.3 (2) A
Z = 4
Monoclinic, P21=n
Mo Kꢄ radiation
ꢅ = 0.11 mmꢃ1
T = 100 K
0.20 ꢄ 0.15 ꢄ 0.10 mm
˚
a = 4.8315 (12) A
˚
b = 19.976 (5) A
˚
c = 6.3551 (13) A
ꢃ = 104.69 (2)ꢁ
Experimental
The title compound, (I), was prepared by a modification of the three-
step procedure of Kamath et al. (2009) and was characterized as a
chemical individuum. The modifications to the published synthesis lie
primarily in a shortening of the reaction time and differences in the
purification methods for obtaining the intermediates in the reaction
process. The first step, as a result of the applied modifications, was
complete after ca 4 h, in contrast with the published procedure with a
reaction completion time of 24 h. Diethylaminomalonate hydro-
chloride (0.05 mol), ethyl (ethoxymethylene)cyanoacetate (0.05 mol)
and sodium methoxide (0.152 mol) in methanol (125 ml) were mixed
carefully at a temperature below ambient conditions (in an ice bath).
The reaction solution was then treated with ultrasound for ca 15 min
before being refluxed for 4 h. The light-yellow solid product of
dimethyl amino-1H-pyrrole-2,4-dicarboxylate was then recrystallized
from toluene and further reacted with formamidine acetate
(0.207 mol) in ethanol (70 ml). The use of a smaller amount of
ethanol [pyrrole–ethanol molar ratio = 1:24, compared with a molar
Data collection
Oxford Xcalibur diffractometer
with a Sapphire2 detector (large
Be window)
Absorption correction: multi-scan
(CrysAlis RED; Oxford
Diffraction, 2009)
Tmin = 0.978, Tmax = 0.989
3740 measured reflections
1050 independent reflections
693 reflections with I > 2ꢆ(I)
Rint = 0.063
Refinement
R[F2 > 2ꢆ(F2)] = 0.049
wR(F2) = 0.102
S = 0.94
91 parameters
H-atom parameteꢃrs3 constrained
˚
Áꢇmax = 0.27 e A
Áꢇmin = ꢃ0.17 e A
ꢃ3
˚
1050 reflections
H atoms were located in difference maps and refined using a riding
˚
˚
model, with C—H = 0.95 A and N—H = 0.88 A, and with Uiso(H) =
1.2Ueq(C,N).
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160 Novotna and Travnıcek
C6H5N3O
Acta Cryst. (2013). C69, 158–161

organic compounds
Table 1
thank Mrs Pavla Richterova for performing the CHN
elemental analyses, Dr Igor Popa for the NMR spectroscopic
measurements and interpretations, and Mr Dmytro Rak for
assistance with the synthesis.
Comparison of selected bond angles (ꢁ) in (I), hypoxanthine and
9-deazainosine monohydrate.
Bond
(I)
Hypoxanthine, Hypoxanthine, 9-Deazainosine
monoclinic
107.34 (18) 103.81 (11)
106.41 (11)
This work (a)
triclinic†
monohydrate
108.7 (2)
105.7 (2)
(c)
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: SK3467). Services for accessing these data are
described at the back of the journal.
C5—N7—C8
103.7 (1),
104.8 (1)
107.0 (1),
106.6 (1)
(b)
C8—N9/C9—C4 106.7 (2)
Reference
References
† Two crystallographically independent molecules within the unit cell. References:
(a) Yang & Xie (2007); (b) Schmalle et al. (1988); (c) Otter et al. (1992).
Allen, F. H. (2002). Acta Cryst. B58, 380–388.
Bantia, S., Miller, P. J., Parker, C. D., Ananth, S. L., Horn, L. L., Kilpatrick,
T. L., Montgomery, J. A. & Sandhu, J. S. (2001). Int. Immunopharmacol. 1,
1199–1210.
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem.
Int. Ed. Engl. 34, 1555–1573.
Table 2
Hydrogen-bond geometry (A, ).
ꢁ
˚
Brandenburg, K. (2011). DIAMOND. Crystal Impact GbR, Bonn, Germany.
Bzowska, A., Kulikowska, E. & Shugar, D. (2000). Pharmacol. Ther. 88, 349–
425.
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
N1—H1ꢀ ꢀ ꢀO1i
N7—H7ꢀ ꢀ ꢀN3ii
C2—H2ꢀ ꢀ ꢀO1iii
0.88
0.88
0.95
1.92
2.09
2.18
2.799 (3)
2.965 (3)
3.106 (3)
175
176
165
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´
Capek, P., Otmar, M., Masojıdkova, M., Votruba, I. & Holy, A. (2003). Collect.
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¨
Clinch, K., Evans, G. B., Frohlich, R. F., Furneaux, R. H., Kelly, P. M., Legentil,
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(2009). J. Med. Chem. 52, 1126–1143.
Symmetry codes: (i) ꢃx þ 2; ꢃy; ꢃz þ 1; (ii) x; y; z þ 1; (iii) x; y; z ꢃ 1.
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55–69.
Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell
refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduc-
tion: CrysAlis RED; program(s) used to solve structure: SHELXS97
(Sheldrick, 2008); program(s) used to refine structure: SHELXL97
(Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008)
and DIAMOND (Brandenburg, 2011); software used to prepare
material for publication: publCIF (Westrip, 2010) and PARST
(Nardelli, 1995).
Nardelli, M. (1995). J. Appl. Cryst. 28, 659.
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´ ´
Otmar, M., Masojıdkova, M., Votruba, I. & Holy, A. (2004). Bioorg. Med.
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114, 668–671.
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This work was supported financially by the Operational
Program for Research and Development for Innovations of
the European Regional Development Fund (grant No.
CZ.1.05/2.1.00/03.0058), by the Operational Program for
Education for Competitiveness of the European Social Fund
(grant No. CZ.1.07/2.3.00/20.0017), by the Ministry of
Education, Youth and Sports of the Czech Republic, and by
Palacky University (grant No. PrF_2012_009). The authors
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Acta Cryst. (2013). C69, 158–161
Novotna and Travnıcek C6H5N3O 161

supplementary materials
supplementary materials
Acta Cryst. (2013). C69, 158-161 [doi:10.1107/S0108270112050767]
Infinite ladder-like chains organized into a three-dimensional zigzag
supramolecular architecture in 9-deazahypoxanthine
Radka Novotná and Zdeněk Trávníček
3H-pyrrolo[3,2-d]pyrimidin-4(5H)-one
Crystal data
C6H5N3O
Mr = 135.13
F(000) = 280
Dx = 1.513 Mg m−3
Mo Kα radiation, λ = 0.71073 Å
Cell parameters from 1593 reflections
θ = 3.1–33.3°
Monoclinic, P21/n
Hall symbol: -P 2yn
a = 4.8315 (12) Å
b = 19.976 (5) Å
c = 6.3551 (13) Å
β = 104.69 (2)°
V = 593.3 (2) Å3
Z = 4
µ = 0.11 mm−1
T = 100 K
Prism, colourless
0.20 × 0.15 × 0.10 mm
Data collection
Oxford Xcalibur
Tmin = 0.978, Tmax = 0.989
diffractometer with Sapphire2 detector (large Be
window)
Radiation source: Enhance (Mo) X-ray Source
Graphite monochromator
Detector resolution: 8.3611 pixels mm-1
ω scans
3740 measured reflections
1050 independent reflections
693 reflections with I > 2σ(I)
Rint = 0.063
θmax = 25.1°, θmin = 3.5°
h = −5→5
k = −23→22
l = −7→7
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Refinement
Refinement on F2
Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.049
wR(F2) = 0.102
Secondary atom site location: difference Fourier
map
Hydrogen site location: inferred from
neighbouring sites
S = 0.94
1050 reflections
91 parameters
0 restraints
Primary atom site location: structure-invariant
direct methods
H-atom parameters constrained
w = 1/[σ2(Fo2) + (0.0548P)2]
where P = (Fo2 + 2Fc2)/3
(Δ/σ)max < 0.001
Δρmax = 0.27 e Å−3
Δρmin = −0.17 e Å−3
Acta Cryst. (2013). C69, 158-161
sup-1

supplementary materials
Special details
Experimental. Elemental analysis (CHN) was performed on a Thermo Scientific Flash 2000 CHNO-S Analyzer. FT–IR
spectra were recorded on a Thermo Nicolet Nexus 670 spectrometer equipped with a micro-ATR module (single
reflection diamond ATR crystal) in the 400–4000 cm-1 range. The 1H, 13C and 15N NMR spectra of the DMSO-d6 or DMF-
d7 solutions were collected at 300 K on a Varian 400 spectrometer at 400.00, 100.58 and 40.53 MHz, respectively. 1H and
13C spectra were calibrated using tetramethylsilane as a reference. The 15N NMR spectrum was measured relative to the
DMF signals. Mass spectra (MS) were recorded on an LTQ Fleet (ThermoFisher Scientific) using the positive
electrospray ionization (ESI+) and full scan mode in ca 10-5 M methanolic solutions.
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 (Å2)
x
y
z
Uiso*/Ueq
N1
H1
O1
C2
H2
N3
C4
C5
C6
N7
H7
C8
H8
C9
H9
0.7585 (4)
0.8929
0.05060 (9)
0.0201
0.2910 (3)
0.3028
0.0185 (5)
0.022*
0.7935 (3)
0.6453 (5)
0.7187
0.04177 (8)
0.07721 (12)
0.0616
0.6563 (2)
0.0909 (4)
−0.0254
0.0220 (4)
0.0213 (6)
0.026*
0.4440 (4)
0.3504 (5)
0.4583 (5)
0.6780 (5)
0.3190 (4)
0.3475
0.12250 (10)
0.14308 (11)
0.11720 (12)
0.06798 (11)
0.14745 (9)
0.1396
0.0454 (3)
0.2234 (4)
0.4322 (4)
0.4763 (4)
0.5707 (3)
0.7108
0.0215 (5)
0.0181 (6)
0.0173 (5)
0.0170 (5)
0.0193 (5)
0.023*
0.1282 (5)
0.0036
0.19201 (12)
0.2197
0.4504 (4)
0.5063
0.0209 (6)
0.025*
0.1421 (5)
0.0327
0.19112 (12)
0.2177
0.2378 (4)
0.1224
0.0212 (6)
0.025*
Atomic displacement parameters (Å2)
U11
U22
U33
U12
U13
U23
N1
O1
C2
N3
C4
C5
C6
N7
C8
C9
0.0138 (10)
0.0185 (9)
0.0211 (11)
0.0274 (10)
0.0257 (14)
0.0234 (12)
0.0188 (13)
0.0179 (13)
0.0173 (12)
0.0213 (11)
0.0176 (13)
0.0207 (14)
0.0202 (11)
0.0198 (9)
0.0040 (9)
0.0032 (8)
0.0045 (7)
0.0040 (10)
0.0039 (9)
0.0046 (10)
0.0054 (10)
0.0052 (10)
0.0042 (8)
0.0045 (10)
−0.0001 (10)
0.0018 (8)
0.0045 (7)
0.0037 (7)
0.0183 (13)
0.0168 (11)
0.0128 (12)
0.0135 (12)
0.0145 (12)
0.0161 (11)
0.0113 (11)
0.0122 (12)
0.0196 (13)
0.0237 (12)
0.0228 (14)
0.0209 (13)
0.0197 (13)
0.0202 (11)
0.0330 (15)
0.0278 (15)
−0.0007 (12)
0.0006 (9)
−0.0015 (11)
0.0004 (9)
−0.0042 (10)
−0.0034 (10)
−0.0050 (10)
0.0010 (9)
−0.0013 (10)
−0.0006 (10)
−0.0014 (10)
0.0012 (8)
−0.0001 (10)
0.0013 (10)
−0.0004 (11)
0.0037 (11)
Acta Cryst. (2013). C69, 158-161
sup-2

supplementary materials
Geometric parameters (Å, º)
N1—C2
N1—C6
N1—H1
O1—C6
C2—N3
C2—H2
N3—C4
C4—C5
1.358 (3)
1.375 (3)
0.8800
C4—C9
C5—N7
C5—C6
N7—C8
N7—H7
C8—C9
C8—H8
C9—H9
1.410 (3)
1.376 (3)
1.422 (3)
1.367 (3)
0.8800
1.253 (3)
1.306 (3)
0.9500
1.370 (3)
0.9500
1.383 (3)
1.396 (3)
0.9500
C2—N1—C6
C2—N1—H1
C6—N1—H1
N3—C2—N1
N3—C2—H2
N1—C2—H2
C2—N3—C4
N3—C4—C5
N3—C4—C9
C5—C4—C9
N7—C5—C4
N7—C5—C6
C4—C5—C6
124.7 (2)
117.7
O1—C6—N1
O1—C6—C5
N1—C6—C5
C8—N7—C5
C8—N7—H7
C5—N7—H7
N7—C8—C9
N7—C8—H8
C9—C8—H8
C8—C9—C4
C8—C9—H9
C4—C9—H9
121.3 (2)
127.3 (2)
111.4 (2)
107.34 (18)
126.3
117.7
125.4 (2)
117.3
117.3
126.3
113.9 (2)
123.1 (2)
130.0 (2)
106.9 (2)
108.7 (2)
129.8 (2)
121.6 (2)
110.4 (2)
124.8
124.8
106.7 (2)
126.7
126.7
Hydrogen-bond geometry (Å, º)
D—H···A
D—H
H···A
D···A
D—H···A
N1—H1···O1i
N7—H7···N3ii
C2—H2···O1iii
0.88
0.88
0.95
1.92
2.09
2.18
2.799 (3)
2.965 (3)
3.106 (3)
175
176
165
Symmetry codes: (i) −x+2, −y, −z+1; (ii) x, y, z+1; (iii) x, y, z−1.
Comparison of selected bond angles (°) in (I), hypoxanthine and 9-deazainosine monohydrate
Hypoxanthine,
monoclinic
103.81 (11)
106.41 (11)
(a)
Hypoxanthine,
triclinic*
9-Deazainosine
monohydrate
108.7 (2)
105.7 (2)
(c)
Bond
(I)
C5—N7—C8
C8—N9/C9—C4
Reference
107.34 (18)
106.7 (2)
103.7 (1), 104.8 (1)
107.0 (1), 106.6 (1)
(b)
This work
Note: (*) two crystallographically independent molecules within the unit cell. References: (a) Yang & Xie (2007); (b) Schmalle et al. (1988); (c) Otter et
al. (1992).
Acta Cryst. (2013). C69, 158-161
sup-3

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