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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 12| December 2012| Pages o3442-o3443

2,6-Di­amino-4-chloro­pyrimidine–benzoic acid (1/1)

aSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: arazaki@usm.my

(Received 12 November 2012; accepted 20 November 2012; online 24 November 2012)

The benzoic acid mol­ecule of the title compound, C4H5ClN4·C7H6O2, is approximately planar, with a dihedral angle of 1.28 (9)° between the carb­oxy group and the benzene ring. In the crystal, two acid and two base mol­ecules are linked through N—H⋯O and O—H⋯N hydrogen bonds, forming a centrosymmetric 2 + 2 unit with R22(8) and R42(8) motifs. These units are further linked through a pair of N—H⋯N hydrogen bonds into a tape structure along [1-20]. The crystal structure also features weak ππ [centroid–centroid distance = 3.5984 (11) Å] and C—H⋯π inter­actions.

Related literature

For the biological activity of pyrimidine and amino­pyrimidine derivatives, see: Hunt et al. (1980[Hunt, W. E., Schwalbe, C. H., Bird, K. & Mallinson, P. D. (1980). J. Biochem. 187, 533-536.]); Baker & Santi (1965[Baker, B. R. & Santi, D. V. (1965). J. Pharm. Sci. 54, 1252-1257.]). For related structures, see: Schwalbe & Williams (1982[Schwalbe, C. H. & Williams, G. J. B. (1982). Acta Cryst. B38, 1840-1843.]); Hu et al. (2002[Hu, M.-L., Ye, M.-D., Zain, S. M. & Ng, S. W. (2002). Acta Cryst. E58, o1005-o1007.]); Chinnakali et al. (1999[Chinnakali, K., Fun, H.-K., Goswami, S., Mahapatra, A. K. & Nigam, G. D. (1999). Acta Cryst. C55, 399-401.]); Skovsgaard & Bond (2009[Skovsgaard, S. & Bond, A. D. (2009). CrystEngComm, 11, 444-453.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C4H5ClN4·C7H6O2

  • Mr = 266.69

  • Monoclinic, P 21 /c

  • a = 8.7817 (17) Å

  • b = 5.7032 (12) Å

  • c = 24.026 (4) Å

  • β = 95.493 (4)°

  • V = 1197.8 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.32 mm−1

  • T = 100 K

  • 0.36 × 0.30 × 0.16 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.895, Tmax = 0.951

  • 7539 measured reflections

  • 2097 independent reflections

  • 1891 reflections with I > 2σ(I)

  • Rint = 0.052

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.101

  • S = 1.09

  • 2097 reflections

  • 183 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.25 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C5–C10 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O1⋯N2 0.87 (2) 1.74 (2) 2.5976 (18) 168 (3)
N4—H2N4⋯O2 0.88 (2) 2.03 (2) 2.894 (2) 171.2 (18)
N4—H1N4⋯O2i 0.88 (2) 2.07 (2) 2.902 (2) 158.2 (19)
N3—H1N3⋯N1ii 0.85 (2) 2.18 (2) 3.020 (2) 171 (2)
C9—H9ACg1iii 0.95 2.99 3.6557 (19) 128
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x, -y+2, -z+1; (iii) [-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Pyrimidine and aminopyrimidine derivatives are biologically important compounds as they occur in nature as components of nucleic acids. Some aminopyrimidine derivatives are used as antifolate drugs (Hunt et al., 1980; Baker & Santi, 1965). The crystal structures of aminopyrimidine derivatives (Schwalbe & Williams, 1982), aminopyrimidine carboxylates (Hu et al., 2002) and co-crystal structures (Chinnakali et al., 1999; Skovsgaard & Bond, 2009) have ben reported. In the present study, hydrogen-bonding patterns in the 2,6-diamino-4-chloropyrimidine–benzoic acid (1/1) co-crystal are investigated.

The asymmetric unit (Fig. 1) contains one 2,6-diamino-4-chloropyrimidine molecule and one benzoic acid molecule. The 2,6-diamino-4-chloropyrimidine molecule is essentially planar, with a maximum deviation of 0.009 (2) Å for atom C4. The carboxyl group of the benzoic acid molecule is twisted slightly from the ring with a dihedral angle between C5–C10 ring and O1/O2/C10/C11 plane being 1.28 (9)°. The bond lengths (Allen et al., 1987) and angles are normal.

In the crystal packing (Fig. 2), the 2,6-diamino-4-chloropyrimidine molecules interact with the carboxylic group of the respective benzoic acid molecules through N4—H2N4···O2 and O1—H1O1···N2 hydrogen bonds, forming a cyclic hydrogen-bonded motif of R22(8) (Bernstein et al., 1995). These motifs are centrosymmetrically paired via N4—H1N4···O2i hydrogen bonds, resulting in a DADA array (Where D is a hydrogen-bond donor and A is a hydrogen-bond acceptor) of quadruple hydrogen bonds (symmetry code in Table 1); this can be represented by the graph-set notations of R22(8) and R42(8). The quadruple hydrogen-bonding motifs are further extended through a couple of N3—H1N3···N1ii hydrogen bonds (symmetry code in Table 1), leading to the formation of hydrogen-bonded supramolecular tape. The crystal structure is further stabilized by ππ interactions between the pyrimidine (Cg2; N1/N2/C1–C4) rings [Cg2···Cg2 = 3.5984 (11) Å; -x, 1 - y, 1 - z] and C—H···π interactions (Table 1) involving the centroid of the C5–C10 (centroid Cg1) ring.

Related literature top

For the biological activity of pyrimidine and aminopyrimidine derivatives, see: Hunt et al. (1980); Baker & Santi (1965). For related structures, see: Schwalbe & Williams (1982); Hu et al. (2002); Chinnakali et al. (1999); Skovsgaard & Bond (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

Experimental top

A hot methanol solutions (20 ml) of 2,6-diamino-4-chloropyrimidine (36 mg, Aldrich) and benzoic acid (30 mg, Merck) were mixed and warmed over a heating magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound (I) appeared after a few days.

Refinement top

O- and N-bound H Atoms were located in a difference Fourier maps and refined freely [O—H = 0.866 (10) Å and N—H = 0.79 (2)–0.88 (2) Å]. The remaining hydrogen atoms were positioned geometrically (C—H = 0.95 Å) and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with atom labels with 50% probability displacement ellipsoids. Dashed lines indicate the hydrogen bonds.
[Figure 2] Fig. 2. The crystal packing of the title compound. H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.
2,6-Diamino-4-chloropyrimidine–benzoic acid (1/1) top
Crystal data top
C4H5ClN4·C7H6O2F(000) = 552
Mr = 266.69Dx = 1.479 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5646 reflections
a = 8.7817 (17) Åθ = 3.0–30.0°
b = 5.7032 (12) ŵ = 0.32 mm1
c = 24.026 (4) ÅT = 100 K
β = 95.493 (4)°Block, colourless
V = 1197.8 (4) Å30.36 × 0.30 × 0.16 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2097 independent reflections
Radiation source: fine-focus sealed tube1891 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
ϕ and ω scansθmax = 25.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1010
Tmin = 0.895, Tmax = 0.951k = 66
7539 measured reflectionsl = 2828
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0471P)2 + 0.4196P]
where P = (Fo2 + 2Fc2)/3
2097 reflections(Δ/σ)max < 0.001
183 parametersΔρmax = 0.25 e Å3
1 restraintΔρmin = 0.24 e Å3
Crystal data top
C4H5ClN4·C7H6O2V = 1197.8 (4) Å3
Mr = 266.69Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.7817 (17) ŵ = 0.32 mm1
b = 5.7032 (12) ÅT = 100 K
c = 24.026 (4) Å0.36 × 0.30 × 0.16 mm
β = 95.493 (4)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
2097 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1891 reflections with I > 2σ(I)
Tmin = 0.895, Tmax = 0.951Rint = 0.052
7539 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 1.09Δρmax = 0.25 e Å3
2097 reflectionsΔρmin = 0.24 e Å3
183 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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) top
xyzUiso*/Ueq
Cl10.05557 (4)0.64565 (9)0.367228 (16)0.03348 (18)
O10.43197 (13)0.5175 (2)0.61239 (5)0.0312 (3)
O20.52962 (16)0.1720 (2)0.59015 (5)0.0372 (3)
N10.07033 (15)0.7543 (3)0.46563 (5)0.0274 (4)
N20.27154 (14)0.5362 (3)0.51588 (5)0.0266 (4)
N30.16941 (19)0.8669 (3)0.55310 (6)0.0313 (4)
N40.37676 (16)0.2112 (3)0.47835 (7)0.0325 (4)
C10.07703 (17)0.5991 (3)0.42471 (7)0.0272 (4)
C20.17389 (17)0.4136 (4)0.42399 (7)0.0287 (4)
H2A0.17340.31080.39290.034*
C30.27541 (17)0.3846 (3)0.47284 (7)0.0272 (4)
C40.17144 (17)0.7163 (3)0.51057 (6)0.0265 (4)
C50.71603 (19)0.1587 (3)0.69200 (7)0.0264 (4)
H5A0.72200.03020.66720.032*
C60.80722 (19)0.1626 (3)0.74236 (7)0.0276 (4)
H6A0.87600.03720.75190.033*
C70.79790 (17)0.3497 (3)0.77877 (7)0.0251 (4)
H7A0.86080.35260.81320.030*
C80.69723 (17)0.5321 (3)0.76507 (7)0.0258 (4)
H8A0.69080.65940.79020.031*
C90.60544 (17)0.5293 (3)0.71455 (7)0.0241 (4)
H9A0.53610.65420.70520.029*
C100.61545 (17)0.3430 (3)0.67768 (6)0.0214 (4)
C110.52134 (18)0.3366 (3)0.62273 (7)0.0249 (4)
H2N30.233 (3)0.851 (4)0.5785 (10)0.039 (6)*
H2N40.432 (2)0.196 (4)0.5105 (10)0.045 (6)*
H1N40.388 (2)0.113 (4)0.4508 (9)0.033 (5)*
H1N30.109 (2)0.983 (4)0.5499 (9)0.037 (6)*
H1O10.386 (3)0.508 (7)0.5789 (7)0.113 (13)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0286 (3)0.0508 (4)0.0183 (2)0.00328 (18)0.01233 (16)0.00310 (18)
O10.0260 (6)0.0437 (8)0.0220 (6)0.0042 (6)0.0080 (5)0.0035 (6)
O20.0521 (8)0.0321 (8)0.0240 (6)0.0019 (6)0.0147 (6)0.0010 (6)
N10.0230 (6)0.0382 (9)0.0190 (7)0.0093 (6)0.0076 (5)0.0077 (7)
N20.0203 (6)0.0395 (9)0.0183 (7)0.0085 (6)0.0059 (5)0.0068 (6)
N30.0318 (8)0.0370 (10)0.0217 (8)0.0044 (7)0.0144 (6)0.0040 (7)
N40.0262 (7)0.0503 (11)0.0195 (7)0.0020 (7)0.0058 (6)0.0009 (7)
C10.0202 (7)0.0439 (11)0.0159 (8)0.0113 (7)0.0071 (6)0.0080 (7)
C20.0218 (8)0.0457 (12)0.0177 (8)0.0074 (8)0.0032 (6)0.0029 (8)
C30.0178 (7)0.0447 (12)0.0181 (8)0.0098 (7)0.0029 (6)0.0071 (7)
C40.0214 (7)0.0387 (11)0.0178 (8)0.0124 (7)0.0062 (6)0.0083 (7)
C50.0325 (9)0.0257 (10)0.0201 (8)0.0009 (7)0.0015 (7)0.0003 (7)
C60.0283 (8)0.0292 (10)0.0244 (8)0.0070 (7)0.0030 (7)0.0050 (7)
C70.0220 (8)0.0322 (10)0.0196 (8)0.0019 (7)0.0053 (6)0.0024 (7)
C80.0249 (8)0.0268 (10)0.0244 (8)0.0006 (7)0.0038 (6)0.0034 (7)
C90.0199 (7)0.0248 (10)0.0267 (8)0.0005 (7)0.0027 (6)0.0028 (7)
C100.0192 (7)0.0263 (9)0.0181 (8)0.0046 (6)0.0014 (6)0.0039 (6)
C110.0243 (8)0.0291 (10)0.0205 (8)0.0063 (7)0.0023 (6)0.0043 (7)
Geometric parameters (Å, º) top
Cl1—C11.7395 (15)C2—C31.414 (2)
O1—C111.306 (2)C2—H2A0.9500
O1—H1O10.866 (10)C5—C61.386 (2)
O2—C111.229 (2)C5—C101.395 (2)
N1—C11.328 (2)C5—H5A0.9500
N1—C41.348 (2)C6—C71.387 (3)
N2—C41.350 (2)C6—H6A0.9500
N2—C31.351 (2)C7—C81.384 (2)
N3—C41.336 (2)C7—H7A0.9500
N3—H2N30.79 (2)C8—C91.392 (2)
N3—H1N30.85 (2)C8—H8A0.9500
N4—C31.328 (3)C9—C101.391 (2)
N4—H2N40.88 (2)C9—H9A0.9500
N4—H1N40.88 (2)C10—C111.490 (2)
C1—C21.358 (3)
C11—O1—H1O1110 (2)C6—C5—C10120.18 (16)
C1—N1—C4114.40 (16)C6—C5—H5A119.9
C4—N2—C3118.60 (14)C10—C5—H5A119.9
C4—N3—H2N3117.1 (16)C5—C6—C7119.92 (16)
C4—N3—H1N3119.2 (15)C5—C6—H6A120.0
H2N3—N3—H1N3123 (2)C7—C6—H6A120.0
C3—N4—H2N4118.1 (15)C8—C7—C6120.20 (15)
C3—N4—H1N4121.4 (13)C8—C7—H7A119.9
H2N4—N4—H1N4121 (2)C6—C7—H7A119.9
N1—C1—C2126.90 (15)C7—C8—C9120.15 (16)
N1—C1—Cl1114.35 (13)C7—C8—H8A119.9
C2—C1—Cl1118.76 (14)C9—C8—H8A119.9
C1—C2—C3115.25 (17)C10—C9—C8119.83 (15)
C1—C2—H2A122.4C10—C9—H9A120.1
C3—C2—H2A122.4C8—C9—H9A120.1
N4—C3—N2117.76 (15)C9—C10—C5119.71 (15)
N4—C3—C2122.23 (17)C9—C10—C11121.29 (15)
N2—C3—C2120.01 (17)C5—C10—C11118.99 (15)
N3—C4—N1116.94 (17)O2—C11—O1123.62 (15)
N3—C4—N2118.24 (15)O2—C11—C10121.44 (16)
N1—C4—N2124.81 (16)O1—C11—C10114.94 (15)
C4—N1—C1—C20.5 (2)C10—C5—C6—C70.3 (3)
C4—N1—C1—Cl1179.02 (11)C5—C6—C7—C80.3 (3)
N1—C1—C2—C31.1 (3)C6—C7—C8—C90.4 (2)
Cl1—C1—C2—C3178.45 (11)C7—C8—C9—C100.2 (2)
C4—N2—C3—N4178.65 (15)C8—C9—C10—C50.9 (2)
C4—N2—C3—C21.2 (2)C8—C9—C10—C11178.71 (14)
C1—C2—C3—N4179.98 (15)C6—C5—C10—C90.9 (2)
C1—C2—C3—N20.1 (2)C6—C5—C10—C11178.67 (15)
C1—N1—C4—N3179.82 (14)C9—C10—C11—O2179.79 (15)
C1—N1—C4—N21.0 (2)C5—C10—C11—O20.6 (2)
C3—N2—C4—N3179.31 (15)C9—C10—C11—O10.5 (2)
C3—N2—C4—N11.9 (2)C5—C10—C11—O1179.08 (14)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C5–C10 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1O1···N20.87 (2)1.74 (2)2.5976 (18)168 (3)
N4—H2N4···O20.88 (2)2.03 (2)2.894 (2)171.2 (18)
N4—H1N4···O2i0.88 (2)2.07 (2)2.902 (2)158.2 (19)
N3—H1N3···N1ii0.85 (2)2.18 (2)3.020 (2)171 (2)
C9—H9A···Cg1iii0.952.993.6557 (19)128
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+2, z+1; (iii) x+1, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC4H5ClN4·C7H6O2
Mr266.69
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)8.7817 (17), 5.7032 (12), 24.026 (4)
β (°) 95.493 (4)
V3)1197.8 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.32
Crystal size (mm)0.36 × 0.30 × 0.16
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.895, 0.951
No. of measured, independent and
observed [I > 2σ(I)] reflections
7539, 2097, 1891
Rint0.052
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.101, 1.09
No. of reflections2097
No. of parameters183
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.25, 0.24

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C5–C10 ring.
D—H···AD—HH···AD···AD—H···A
O1—H1O1···N20.867 (18)1.74 (2)2.5976 (18)168 (3)
N4—H2N4···O20.88 (2)2.03 (2)2.894 (2)171.2 (18)
N4—H1N4···O2i0.88 (2)2.07 (2)2.902 (2)158.2 (19)
N3—H1N3···N1ii0.85 (2)2.18 (2)3.020 (2)171 (2)
C9—H9A···Cg1iii0.952.993.6557 (19)128
Symmetry codes: (i) x+1, y, z+1; (ii) x, y+2, z+1; (iii) x+1, y+1/2, z+3/2.
 

Footnotes

Thomson Reuters ResearcherID: A-5599-2009.

Acknowledgements

The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the research facilities and Fundamental Research Grant Scheme (FRGS) No. 203/PFIZIK/6711171 to conduct this work. KT thanks The Academy of Sciences for the Developing World and USM for a TWAS–USM fellowship.

References

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Volume 68| Part 12| December 2012| Pages o3442-o3443
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