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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoSTRUCTURAL
CHEMISTRY
ISSN: 2053-2296
Volume 62| Part 2| February 2006| Pages o107-o110
doi:10.1107/S0108270105037856

Hydrogen-bonding patterns in trimethoprim picolinate and 2-amino-4,6-di­methyl­pyrimidinium picolinate hemihydrate

CROSSMARK_Color_square_no_text.svg
Madhukar Hemamalini,a Packianathan Thomas Muthiaha* and Daniel E. Lynchb

aSchool of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India, and bFaculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, England
*Correspondence e-mail: tommtrichy@yahoo.co.in

(Received 26 September 2005; accepted 17 November 2005; online 31 January 2006)

In the title compounds, namely 2,4-diamino-5-[(3,4,5-trimethoxy­phenyl)methyl]­pyrimidin-1-ium pyridine-2-carboxyl­ate, C14H19N4O3+·C6H4NO2−, (I)[link], and 2-amino-4,6-dimethyl­pyrimidin-1-ium pyridine-2-carboxyl­ate hemihydrate, C6H10N3+·C6H4NO2−·0.5H2O, (II)[link], the trimethoprim and 2-amino-4,6-dimethyl­pyrimidin-1-ium cations are protonated at one of the pyrimidine N atoms. In (I)[link], bifurcated hydrogen bonds are observed between a picolinate O atom, the protonated N atom and the 2-amino group; the graph-set designator is R21(6). The pyrimidine moieties of the trimethoprim cations are centrosymmetrically paired through a pair of N—H⋯N hydrogen bonds. In addition to the base pairing, one of the picolinate O atoms bridges the 2- and 4-amino groups on either side of the paired bases, resulting in a complementary DADA array. In (II)[link], the carboxyl­ate group of the picolinate anion binds with the protonated pyrimidine N atom and the 2-amino group of the pyrimidine moiety through a pair of N—H⋯O hydrogen bonds, leading to the common ring motif R22(8). The water mol­ecule, which resides on a twofold rotation axis, bridges the carboxyl­ate group of the picolinate anion via O—H⋯O hydrogen bonds.

Comment

Hydrogen-bonding patterns involving amino­pyrimidine and carboxyl­ates have been observed in drug-receptor inter­actions, protein–nucleic acid inter­actions and supramolecular architectures (Desiraju, 1989[Desiraju, G. R. (1989). Crystal Engineering: The Design of Organic Solids. Amsterdam: Elsevier.]). Studies of such inter­actions are also of current inter­est because of their applications in drug design and the crystal engineering of pharmaceuticals (Stanley et al., 2005[Stanley, N., Muthiah, P. T., Geib, S. J., Luger, P., Weber, M. & Messerschmidt, M. (2005). Tetrahedron, 61, 7201-7210.]). Pyrimidine and amino­pyrimidine derivatives are biologically important as they occur in nature as components of nucleic acid. Some amino­pyrimidine derivatives are used as anti­folate drugs (Hunt et al., 1980[Hunt, W. E., Schwalbe, C. H., Bird, K. & Mallinson, P. D. (1980). Biochem. J. 187, 533-536.]; Baker & Santi, 1965[Baker, B. R. & Santi, D. V. (1965). J. Pharm. Sci. 44, 1252-1257.]). Trimethoprim [2,4-diamino-5-(3,4,5-trimethoxy­benzyl)­pyrimidine, TMP] is a well known anti­folate drug. It selectively inhibits the bacterial dihydro­folate reductase (DHFR) enzyme (Hitchings et al., 1988[Hitchings, G. H., Kuyper, L. F. & Baccananari, D. P. (1988). Design of Enzyme Inhibitors as Drugs, edited by M. Sandler & H. J. Smith, p. 343. New York: Oxford University Press.]). Picolinic acid (pyridine-2-carboxylic acid) is a well known terminal tryptophan metabolite (Mahler & Cordes, 1971[Mahler, H. R. & Cordes, E. H. (1971). Biological Chemistry, 2nd ed., pp. 801-803. New York: Harper and Row Publishers.]). It induces apoptosis in leukaemia HL-60 cells (Ogata et al., 2000[Ogata, S., Takeuchi, M., Fujita, H., Shibata, K., Okumura, K. & Taguchi, H. (2000). Biosci. Biotechnol. Biochem. 64, 327-332.]). The crystal structures of a dinuclear oxomolybdenum(V) complex of picolinate (Okabe et al., 2002[Okabe, N., Isomoto, N. & Odoko, M. (2002). Acta Cryst. E58, m1-m3.]), of catena-poly[[[bis­(2-pyridine­carboxylato)copper(II)]-μ-benzene-1,2,4,5-tetracarboxylic acid] dihydrate] (Wang et al., 2005[Wang, L., Zhou, D.-H. & Zhang, J.-P. (2005). Acta Cryst. E61, m958-m960.]) and of trans-dichloro­(dimethyl ­sulfoxide)(2-picoline)platinum(II) (Melanson et al., 1978[Melanson, R. & Rochon, F. D. (1978). Acta Cryst. B34, 1125-1127.]) have been reported. In this paper, the crystal structures of trimethoprim (TMP) picolinate, (I)[link], and 2-amino-4,6-dimethyl­pyrimidinium (AMPY) picolinate hemihydrate, (II)[link], are described.

[Scheme 1]

Views of (I)[link] and (II)[link] are shown in Figs. 1[link](a) and 1(b), respectively. In (I)[link], the asymmetric unit contains a trimethoprim cation and a picolinate anion. In (II)[link], one 2-amino-4,6-dimethyl­pyrimidinium cation, one picolinate anion and one half-molecule of water (the O atom of the water mol­ecule lies on a twofold axis) constitute the asymmetic unit. In both structures, the pyrimidine moieties are protonated at N1, leading to an increase in inter­nal angles (see angles C2—N1—C6 in Tables 1[link] and 3[link]) compared with neutral TMP (Koetzle & Williams, 1976[Koetzle, T. F. & Williams, G. J. B. (1976). J. Am. Chem. Soc. 98, 2074-2078.]) and AMPY (Panneerselvam et al., 2004[Panneerselvam, P., Muthiah, P. T. & Francis, S. (2004). Acta Cryst. E60, o747-o749.]). In (I)[link], the dihedral angle between the pyrimidine and benzene rings is 76.06 (7)°. This value is close to that found in TMP–carboxyl­ate salts (Raj, Stanley et al., 2003[Raj, S. B., Stanley, N., Muthiah, P. T., Bocelli, G., Oll'a, R. & Cantoni, A. (2003). Cryst. Growth Des. 3, 567-571.]). The C4—C5—C7—C8 and C5—C7—C8—C9 torsion angles are −68.79 (18) and 168.05 (14)°, respectively.

In (I)[link], atom O5 of the carboxyl­ate group accepts a H atom from protonated atom N1 and the 2-amino group of the pyrimidine ring, forming a cyclic hydrogen-bonded bimolecular pattern [graph-set R21(6); Etter, 1990[Etter, M. C. (1990). Acc. Chem. Res. 23, 120-126.]; Bernstein et al., 1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]]. A similar pattern was also observed in the crystal structure of trimethoprim 3-carb­oxy-4-hydroxy­benzene­sulfonate dihydrate (Raj, Sethuraman et al., 2003[Raj, S. B., Sethuraman, V., Francis, S., Hemamalini, M., Muthiah, P. T., Bocelli, G., Cantoni, A., Rychlewska, U. & Warzajtis, B. (2003). CrystEngComm, 5, 70-76.]). This is different from the common R22(8) pattern observed in the crystal structures of amino­pyrimidine–carboxyl­ate salts (Stanley et al., 2002[Stanley, N., Sethuraman, V., Muthiah, P. T., Luger, P. & Weber, M. (2002). Cryst. Growth Des. 6, 631-635.]). The pyrimidine moieties form base pairs through N4—H⋯N3 (Table 2[link]) hydrogen bonds involving the 4-amino group and atom N3. In addition to the base pairing, a hydrogen-bonded acceptor (atom O4 from the picolinate anion) bridges the 4- and 2-amino groups on both sides of the pairing, leading to a complementary linear DADA array (D = donor in hydrogen bonds and A = acceptor in hydrogen bonds), with the rings having the graph-set notations R23(8), R22(8) and R23(8). The same type of DADA array has also been observed in the crystal structures of trimethoprim trifluoro­acetate (Francis et al., 2002[Francis, S., Muthiah, P. T., Bocelli, G. & Righi, L. (2002). Acta Cryst. E58, o717-o719.]) and a copper(II) phthalate trimethoprim complex (Raj, Muthiah et al., 2003[Raj, S. B., Muthiah, P. T., Bocelli, G. & Cantoni, A. (2003). Inorg. Chem. Commun. 6, 748-751.]). The characteristic hydrogen-bonded rings observed in the structure aggregate into a supramolecular ladder consisting of a pair of chains, each of which is built up of alternating TMP and picolinate anions (Fig. 2[link]).

In (II)[link], the carboxyl­ate group (atoms O1 and O2) of the picolinate anion inter­acts with protonated atom N1 and the 2-­amino group of the pyrimidine moiety through a pair of N—H⋯O hydrogen bonds, leading to the common ring motif with graph-set notation R22(8) (Lynch et al., 2004[Lynch, D. E. & Jones, G. D. (2004). Acta Cryst. B60, 748-754.]). This is reminiscent of the trimethoprim–carboxyl­ate inter­actions observed in the DHFR–TMP complexes (Kuyper, 1989[Kuyper, L. F. (1989). Computer-Aided Drug Design: Methods and Applications, edited by T. J. Perun & C. L. Propst, ch. 9, pp. 327-370. New York: Marcel Dekker Inc.]). The water mol­ecule, which resides on a twofold rotation axis, bridges the carboxyl­ate groups of the picolinate anions via O—H⋯O hydrogen bonds. One of the H atoms of the 2-amino group is also involved in bifurcated hydrogen bonding with carboxyl atom O2 and the pyridine N atom to form a five-membered hydrogen-bonded ring [R21(5); Fig. 3[link]].

[Figure 1]
Figure 1
Views of (a) (I)[link] and (b) (II)[link], showing the atom-labelling schemes and 50% probability displacement ellipsoids. H atoms are shown as small spheres of arbitrary radii.
[Figure 2]
Figure 2
The hydrogen-bonding patterns (dashed lines) in (I)[link]. [Symmetry codes: (i) 2 − x, 2 − y, 1 − z; (ii) 1 − x, 1 − y, 1 − z; (iii) x − 1, y − 1, z.]
[Figure 3]
Figure 3
The hydrogen-bonding patterns (dashed lines) in (II)[link]. [Symmetry code: (i) [{1\over 2}] − x, [{3\over 2}] − y, 1 − z.]

Experimental

A hot methano­l solution of picolinic acid (61.5 mg, obtained from SD Fine Chemicals Ltd) was mixed with a hot aqueous solution of trimethoprim [for (I); 145 mg, obtained from Shilpa Anti­biotics Ltd] or 2-amino-4,6-dimethyl­pyrimidine [for (II); 63.25 mg, obtained from Merck]. The mixtures were cooled slowly and kept at room temperature. After a few days, colourless block-shaped crystals of (I)[link] and (II)[link] were obtained from the corresponding solutions.

Compound (I)[link]

Crystal data

  • C14H19N4O3+·C6H4NO2−

  • Mr = 413.43

  • Triclinic, [P \overline 1]

  • a = 9.0642 (3) Å

  • b = 10.2730 (3) Å

  • c = 12.1188 (4) Å

  • α = 108.051 (17)°

  • β = 98.741 (2)°

  • γ = 107.517 (2)°

  • V = 985.03 (14) Å3

  • Z = 2

  • Dx = 1.394 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 3758 reflections

  • θ = 3.1–27.6°

  • μ = 0.10 mm−1

  • T = 120 (2) K

  • Block, colourless

  • 0.22 × 0.20 × 0.16 mm
Data collection

  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • 17816 measured reflections

  • 4537 independent reflections

  • 3758 reflections with I > 2σ(I)

  • Rint = 0.036

  • θmax = 27.6°

  • h = −11 → 11

  • k = −13 → 13

  • l = −15 → 15
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.141

  • S = 1.13

  • 4537 reflections

  • 275 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0748P)2 + 0.2682P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.47 e Å−3

  • Δρmin = −0.47 e Å−3

  • Extinction correction: SHELXL97

  • Extinction coefficient: 0.138 (9)

Table 1
Selected geometric parameters (Å, °) for (I)[link]

O1—C12 1.381 (2)
O1—C14 1.428 (2)
O2—C11 1.3826 (18)
O2—C15 1.429 (2)
O3—C10 1.363 (2)
O3—C16 1.425 (2)
O4—C22 1.255 (2)
O5—C22 1.253 (2)
C2—N1—C6 119.87 (14)
C2—N3—C4 118.52 (14)
N2—C2—N3 119.92 (14)
N1—C2—N3 121.87 (14)
N1—C2—N2 118.21 (14)
N3—C4—N4 116.74 (14)

Table 2
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O5 0.88 1.92 2.7308 (19) 151
N1—H1⋯N5 0.88 2.39 3.0441 (19) 131
N2—H2A⋯O4i 0.88 2.00 2.8693 (19) 169
N2—H2B⋯O5 0.88 2.02 2.7982 (19) 147
N4—H4A⋯N3ii 0.88 2.12 2.9966 (18) 173
N4—H4B⋯O4iii 0.88 2.14 2.8412 (18) 137
C14—H14A⋯O2 0.96 2.56 2.899 (3) 101
C17—H17⋯O3iv 0.93 2.49 3.141 (2) 128
Symmetry codes: (i) -x+2, -y+2, -z+1; (ii) -x+1, -y+1, -z+1; (iii) x-1, y-1, z; (iv) -x, -y-1, -z.

Compound (II)[link]

Crystal data

  • C6H10N3+·C6H4NO2−·0.5H2O

  • Mr = 255.28

  • Monoclinic, C 2/c

  • a = 15.7666 (4) Å

  • b = 8.7980 (1) Å

  • c = 18.5038 (4) Å

  • β = 102.7400 (10)°

  • V = 2503.55 (9) Å3

  • Z = 8

  • Dx = 1.355 Mg m−3

  • Mo Kα radiation

  • Cell parameters from 2204 reflections

  • θ = 3.3–26.0°

  • μ = 0.10 mm−1

  • T = 120 K

  • Block, colourless

  • 0.4 × 0.2 × 0.1 mm
Data collection

  • Nonius KappaCCD area-detector diffractometer

  • φ and ω scans

  • 16549 measured reflections

  • 2451 independent reflections

  • 2204 reflections with I > 2σ(I)

  • Rint = 0.026

  • θmax = 26.0°

  • h = −19 → 19

  • k = −10 → 10

  • l = −22 → 22
Refinement

  • Refinement on F2

  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.143

  • S = 1.25

  • 2451 reflections

  • 171 parameters

  • H-atom parameters constrained

  • w = 1/[σ2(Fo2) + (0.0834P)2 + 1.0121P] where P = (Fo2 + 2Fc2)/3

  • (Δ/σ)max < 0.001

  • Δρmax = 0.78 e Å−3

  • Δρmin = −0.82 e Å−3

  • Extinction correction: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.])

  • Extinction coefficient: 0.060 (4)

Table 3
Selected geometric parameters (Å, °) for (II)[link]

O1—C14 1.2687 (18)
O2—C14 1.2430 (18)
N1—C2 1.3642 (17)
N1—C6 1.3591 (18)
N2—C2 1.3190 (18)
N3—C4 1.3270 (19)
N3—C2 1.3558 (18)
N4—C13 1.3409 (19)
N4—C9 1.3410 (18)
C2—N1—C6 121.13 (12)
C2—N3—C4 117.42 (12)
C9—N4—C13 117.73 (12)
N1—C2—N2 118.83 (12)
N1—C2—N3 121.72 (13)
N2—C2—N3 119.45 (12)
N3—C4—C7 116.99 (12)
N3—C4—C5 122.80 (13)
N1—C6—C8 116.34 (12)
N1—C6—C5 118.40 (13)
N4—C9—C14 116.70 (12)
N4—C9—C10 122.74 (13)
N4—C13—C12 123.12 (15)
O1—C14—O2 126.11 (14)
O2—C14—C9 117.86 (13)
O1—C14—C9 116.03 (12)

Table 4
Hydrogen-bond geometry (Å, °) for (II)[link]

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O1 0.88 1.80 2.6657 (15) 168
O1W—H1W⋯O1 0.99 2.00 2.9588 (14) 164
N2—H2A⋯O2i 0.88 2.53 2.9166 (16) 108
N2—H2A⋯N4i 0.88 2.09 2.9645 (16) 170
N2—H2B⋯O2 0.88 1.93 2.8125 (16) 175
Symmetry code: (i) [-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1].

For compound (I)[link], all H atoms were placed in idealized positions and refined as riding, with C—H = 0.93–0.97 Å and N—H = 0.88 Å, and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C,N). For compound (II)[link], the H atoms of the water mol­ecules were located in a difference Fourier map and refined as riding, with O—H = 0.98 Å and Uiso(H) = 1.5Ueq(O). The other H atoms were placed in idealized positions and refined as riding, with C—H = 0.95–0.98 Å and N—H = 0.88 Å, and Uiso(H) = 1.2Ueq(C,N). The highest peak in the final difference map was found at a distance of 1.29 Å from H13 and the deepest hole was 0.72 Å from C14.

For both compounds, data collection: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks global, I, II. DOI: 10.1107/S0108270105037856/sq1233sup1.cif

Structure factors: contains datablock pmt2. DOI: 10.1107/S0108270105037856/sq1233Isup2.hkl

Structure factors: contains datablock II. DOI: 10.1107/S0108270105037856/sq1233IIsup3.hkl


Comment top

Hydrogen-bonding patterns involving aminopyrimidine and carboxylates have been observed in drug-receptor interactions, protein–nucleic acid interactions and supramolecular architectures (Desiraju, 1989). Studies of such interactions are also of current interest because of their applications in drug design and the crystal engineering of pharmaceuticals (Stanley et al., 2005). Pyrimidine and aminopyrimidine derivatives are biologically important as they occur in nature as components of nucleic acid. Some aminopyrimidine derivatives are used as antifolate drugs (Hunt et al., 1980; Baker & Santi, 1965). Trimethoprim [2,4-diamino-5-(3',4',5'-trimethoxybenzyl)pyrimidine, TMP] is a well known antifolate drug. It selectively inhibits the bacterial dihydrofolate reductase (DHFR) enzyme (Hitchings et al., 1988). Picolinic acid (pyridine-2-carboxylic acid) is a well known terminal tryptophan metabolite (Mahler & Cordes, 1971). It induces apoptosis in leukaemia HL-60 cells (Ogata et al., 2000). The crystal structures of a dinuclear oxomolybdenum(V) complex of picolinate (Okabe et al., 2002), of catena-poly[[bis(2-pyridinecarboxylic acid] dihydrate (Wang et al., 2005) and of trans-dichloro(dimethylsulfoxide)(2-picoline)platinum(II) (Melanson et al., 1978) have been reported. In this paper, the crystal structures of trimethoprim (TMP) picolinate, (I), and 2-amino-4,6-dimethylpyrimidinium (AMPY) picolinate hemihydrate, (II), are described.

Views of (I) and (II) are shown in Figs. 1(a) and 1(b), respectively. In (I), the asymmetric unit contains a trimethoprim cation and a picolinate anion. In (II), one 2-amino-4,6-dimethylpyrimidinium cation, one picolinate anion and one half of a water molecule (the O atom of the water molecule lies on a twofold axis) constitute the asymmetic unit. In both structures, the pyrimidine moieties are protonated at N1, leading to an increase in internal angles (see angles C2—N1—C6 in Tables 1 and 3) compared with neutral TMP (Koetzle & Williams, 1976) and AMPY (Panneerselvam et al., 2004). In (I), the dihedral angle between the pyrimidine and phenyl rings is 76.06 (7)°. This value is close to that found in TMP-carboxylate salts (Raj et al., 2003 Which reference?). The C4—C5—C7—C8 and C5—C7—C8—C9 torsion angles are −68.79 (18) and 168.05 (14)°, respectively.

In (I), atom O5 of the carboxylate accepts an H atom from the protonated atom N1 and the 2-amino group of the pyrimidine ring, forming a cyclic hydrogen-bonded bimolecular pattern [graph-set R21(6); Etter, 1990; Bernstein et al., 1995]. A similar pattern was also observed in the crystal structure of trimethoprim 3-carboxy-4-hydroxybenzenesulfonate dihydrate (Raj, Muthiah et al., 2003 Correct?). This is different from the common R22(8) pattern observed in the crystal structures of aminopyrimidine–carboxylate salts (Stanley et al., 2002). The pyrimidine moieties form base pairs through N4—H···N3 (Table 2) hydrogen bonds involving the 4-amino group and atom N3. In addition to the base pairing, a hydrogen-bonded acceptor (atom O4 from the picolinate anion) bridges the 4-amino and 2-amino groups on both sides of the pairing, leading to a complementary linear DADA array (D = donor in hydrogen bonds and A = acceptor in hydrogen bonds), with the rings having the graph-set notations R23(8), R22(8) and R23(8). The same type of DADA array has also been observed in the crystal structures of trimethoprim trifluoroacetate (Francis et al., 2002) and a copper(II) phthalate trimethoprim complex (Raj et al., 2003 Which reference?). The characteristic hydrogen-bonded rings observed in the structure aggregate into a supramolecular ladder consisting of a pair of chains, each of which is built up of alternating TMP and picolinate anions (Fig. 2).

In (II), the carboxylate group (atoms O1 and O2) of the picolinate anion interacts with protonated atom N1 and the 2-amino group of the pyrimidine moiety through a pair of N—H···O hydrogen bonds, leading to the common ring motif with graph-set notation R22(8) (Lynch et al., 2004). This is reminiscent of the trimethoprim–carboxylate interactions observed in the DHFR–TMP complexes (Kuyper, 1989). The water molecule, which resides on a twofold rotation axis, bridges the carboxylate groups of the picolinate anions via O—H···O hydrogen bonds. One of the H atoms of the 2-amino group is also involved in bifurcated hydrogen bonding with the carboxyl atom O2 and the pyridine N atom to form a five-membered hydrogen-bonded ring [R21(5); Fig. 3].

Please ensure the three Raj et al. (2003) references are each uniquely cited.

Experimental top

A hot methanolic solution of picolinic acid (61.5 mg, obtained from SD Fine Chemicals Ltd) was mixed with a hot aqueous solution of trimethoprim [for (I)] (145 mg, obtained from Shilpa Antibiotics Ltd) or 2-amino-4,6-dimethylpyrimidine [for (II)] (63.25 mg, obtained from Merck). The mixtures were cooled slowly and kept at room temperature. After a few days, blocks of colourless crystals of (I) and (II) were obtained from the corresponding solutions.

Refinement top

For compound (I), all H atoms were placed in idealized locations and refined as riding, with C—H = 0.93–0.97 Å and N—H = 0.88 Å, and with Uiso(H) = ?Ueq(C,N). Please complete.

For compound (II), the H atoms of the water molecules were located in a difference Fourier map and refined as riding, with O—H = 0.98 Å and with Uiso(H) = ?Ueq(O). Please complete. The other H atoms were placed in idealized locations and refined as riding, with C—H = 0.95–0.98 Å and N—H = 0.88 Å, and with Uiso(H) = ?Ueq(C,N). Please complete. The highest peak in the difference map was found at a distance of 1.29 Å from H13 and the deepest hole is 0.72 Å from C14.

Computing details top

For both compounds, data collection: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998); cell refinement: DENZO and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON.

Figures top
[Figure 1] Fig. 1. Views of (a) (I) and (b) (II), with the atom-labelling schemes and 50% probability displacement ellipsoids. H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. The hydrogen-bonding patterns in (I) (dashed lines). [Symmetry codes: (i) x, 1 + y, z; (ii) 2 − x, 1 − y, 1 − z; (iii) 1 − x, 1 − y, 1 − z; (iv) x − 1, y, z.]
[Figure 3] Fig. 3. The hydrogen-bonding patterns in (II) (dashed lines). [Symmetry code: (i) 1/2 − x, 3/2 − y, 1 − z.]
(I) 5-[(3,4,5-trimethoxyphenyl)methyl]-2,4 − d-aminopyrimidin-1-ium pyridine-2-carboxylate top
Crystal data top
C14H19N4O3+·C6H4NO2−Z = 2
Mr = 413.43F(000) = 436
Triclinic, P1Dx = 1.394 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.0642 (3) ÅCell parameters from 3758 reflections
b = 10.2730 (3) Åθ = 3.1–27.6°
c = 12.1188 (4) ŵ = 0.10 mm−1
α = 108.051 (17)°T = 120 K
β = 98.741 (2)°Block, colourless
γ = 107.517 (2)°0.22 × 0.20 × 0.16 mm
V = 985.03 (14) Å3
Data collection top
Nonius KappaCCD area-detector
diffractometer		3758 reflections with I > 2σ(I)
Radiation source: Bruker Nonius FR591 rotating anodeRint = 0.036
Graphite monochromatorθmax = 27.6°, θmin = 3.1°
ϕ and ω scansh = −11→11
17816 measured reflectionsk = −13→13
4537 independent reflectionsl = −15→15
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.051H-atom parameters constrained
wR(F2) = 0.141 w = 1/[σ2(Fo2) + (0.0748P)2 + 0.2682P]
where P = (Fo2 + 2Fc2)/3
S = 1.13(Δ/σ)max < 0.001
4537 reflectionsΔρmax = 0.47 e Å−3
275 parametersΔρmin = −0.47 e Å−3
2 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001Fc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.138 (9)
Crystal data top
C14H19N4O3+·C6H4NO2−γ = 107.517 (2)°
Mr = 413.43V = 985.03 (14) Å3
Triclinic, P1Z = 2
a = 9.0642 (3) ÅMo Kα radiation
b = 10.2730 (3) ŵ = 0.10 mm−1
c = 12.1188 (4) ÅT = 120 K
α = 108.051 (17)°0.22 × 0.20 × 0.16 mm
β = 98.741 (2)°
Data collection top
Nonius KappaCCD area-detector
diffractometer		3758 reflections with I > 2σ(I)
17816 measured reflectionsRint = 0.036
4537 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0512 restraints
wR(F2) = 0.141H-atom parameters constrained
S = 1.13Δρmax = 0.47 e Å−3
4537 reflectionsΔρmin = −0.47 e Å−3
275 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All e.s.d.'s are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
O10.29547 (13)0.29892 (14)−0.04713 (10)0.0319 (4)
O2−0.03386 (13)0.12018 (12)−0.17057 (9)0.0258 (3)
O3−0.26112 (13)0.17969 (13)−0.07534 (10)0.0317 (3)
N10.56507 (14)0.87061 (13)0.40540 (11)0.0196 (3)
N20.79043 (15)0.84689 (14)0.50036 (12)0.0254 (4)
N30.54430 (14)0.66108 (13)0.45274 (10)0.0183 (3)
N40.30117 (14)0.47725 (13)0.40408 (11)0.0200 (3)
C20.63246 (17)0.79137 (15)0.45279 (12)0.0186 (4)
C40.38491 (16)0.60563 (15)0.40065 (12)0.0171 (4)
C50.30918 (16)0.67967 (15)0.34116 (12)0.0178 (4)
C60.40562 (16)0.81274 (15)0.34830 (12)0.0188 (4)
C70.13508 (16)0.61038 (15)0.27220 (12)0.0191 (4)
C80.09541 (17)0.47753 (15)0.15650 (12)0.0187 (4)
C9−0.06572 (17)0.38872 (16)0.09793 (12)0.0208 (4)
C10−0.10754 (17)0.27040 (16)−0.01023 (13)0.0222 (4)
C110.01190 (17)0.23695 (16)−0.06140 (12)0.0213 (4)
C120.17131 (17)0.32655 (17)−0.00353 (13)0.0218 (4)
C130.21267 (17)0.44543 (16)0.10498 (13)0.0216 (4)
C140.2884 (3)0.2868 (3)−0.16859 (18)0.0454 (7)
C15−0.0113 (2)−0.00803 (18)−0.16083 (15)0.0330 (5)
C16−0.38648 (19)0.1978 (2)−0.02138 (16)0.0418 (6)
O41.00904 (12)1.29703 (12)0.42584 (10)0.0273 (3)
O50.84420 (13)1.09113 (12)0.43359 (11)0.0299 (3)
N50.58438 (15)1.12103 (13)0.31752 (11)0.0224 (3)
C170.45697 (18)1.14181 (17)0.26488 (13)0.0244 (4)
C180.46611 (19)1.26903 (17)0.24437 (13)0.0253 (4)
C190.61429 (19)1.38263 (17)0.28288 (14)0.0260 (4)
C200.74732 (18)1.36326 (16)0.33792 (13)0.0224 (4)
C210.72833 (17)1.23095 (15)0.35188 (12)0.0195 (4)
C220.87224 (17)1.20425 (16)0.40862 (13)0.0212 (4)
H10.630900.955000.407200.0500*
H2A0.840000.793000.522000.0500*
H2B0.847000.929600.494700.0500*
H4A0.353400.443400.448900.0500*
H4B0.195800.441700.382800.0500*
H60.361700.866200.313200.0230*
H7A0.103100.684100.252100.0230*
H7B0.071900.579900.323900.0230*
H9−0.145600.409100.131800.0250*
H130.320300.503900.143200.0260*
H14A0.236100.18520−0.221700.0540*
H14B0.395400.32420−0.176200.0540*
H14C0.229000.34290−0.189500.0540*
H15A0.099900.01630−0.123500.0400*
H15B−0.04250−0.08340−0.239800.0400*
H15C−0.07600−0.04320−0.112700.0400*
H16A−0.372000.180200.052100.0500*
H16B−0.488500.12900−0.075800.0500*
H16C−0.383400.29650−0.004100.0500*
H170.356701.066600.240700.0290*
H180.374901.277800.205700.0300*
H190.624501.470400.272100.0310*
H200.848201.438200.365100.0270*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0238 (6)0.0449 (7)0.0257 (6)0.0175 (5)0.0085 (4)0.0061 (5)
O20.0292 (6)0.0270 (6)0.0170 (5)0.0120 (5)0.0025 (4)0.0030 (4)
O30.0182 (5)0.0372 (7)0.0232 (6)0.0041 (5)0.0019 (4)−0.0026 (5)
N10.0184 (6)0.0172 (6)0.0213 (6)0.0048 (5)0.0031 (5)0.0077 (5)
N20.0179 (6)0.0226 (6)0.0335 (7)0.0032 (5)0.0002 (5)0.0150 (6)
N30.0173 (6)0.0182 (6)0.0173 (6)0.0051 (5)0.0022 (4)0.0067 (5)
N40.0178 (6)0.0198 (6)0.0208 (6)0.0044 (5)0.0022 (5)0.0095 (5)
C20.0188 (7)0.0201 (7)0.0161 (6)0.0068 (5)0.0040 (5)0.0067 (5)
C40.0188 (7)0.0180 (6)0.0127 (6)0.0067 (5)0.0041 (5)0.0038 (5)
C50.0187 (7)0.0184 (7)0.0152 (6)0.0074 (5)0.0038 (5)0.0047 (5)
C60.0195 (7)0.0196 (7)0.0175 (6)0.0086 (5)0.0033 (5)0.0068 (5)
C70.0165 (7)0.0199 (7)0.0197 (7)0.0069 (5)0.0027 (5)0.0068 (5)
C80.0203 (7)0.0202 (7)0.0166 (6)0.0081 (6)0.0028 (5)0.0087 (5)
C90.0180 (7)0.0245 (7)0.0184 (7)0.0078 (6)0.0042 (5)0.0064 (6)
C100.0178 (7)0.0247 (7)0.0200 (7)0.0059 (6)0.0016 (5)0.0068 (6)
C110.0237 (7)0.0228 (7)0.0154 (7)0.0092 (6)0.0033 (5)0.0050 (5)
C120.0200 (7)0.0278 (8)0.0214 (7)0.0126 (6)0.0070 (5)0.0098 (6)
C130.0180 (7)0.0241 (7)0.0204 (7)0.0069 (6)0.0021 (5)0.0079 (6)
C140.0455 (11)0.0667 (14)0.0455 (11)0.0300 (10)0.0296 (9)0.0322 (10)
C150.0374 (9)0.0266 (8)0.0289 (8)0.0143 (7)0.0029 (7)0.0029 (7)
C160.0181 (8)0.0458 (11)0.0364 (10)0.0032 (7)0.0048 (7)−0.0075 (8)
O40.0191 (5)0.0228 (6)0.0380 (6)0.0038 (4)0.0037 (4)0.0147 (5)
O50.0199 (5)0.0265 (6)0.0451 (7)0.0052 (4)0.0030 (5)0.0217 (5)
N50.0200 (6)0.0209 (6)0.0241 (6)0.0071 (5)0.0027 (5)0.0077 (5)
C170.0216 (7)0.0235 (7)0.0241 (7)0.0081 (6)0.0027 (6)0.0055 (6)
C180.0284 (8)0.0306 (8)0.0215 (7)0.0170 (7)0.0068 (6)0.0099 (6)
C190.0342 (8)0.0243 (7)0.0274 (8)0.0162 (7)0.0120 (6)0.0133 (6)
C200.0243 (7)0.0204 (7)0.0232 (7)0.0081 (6)0.0089 (6)0.0080 (6)
C210.0206 (7)0.0188 (7)0.0177 (6)0.0067 (6)0.0054 (5)0.0055 (5)
C220.0207 (7)0.0185 (7)0.0222 (7)0.0055 (6)0.0049 (5)0.0070 (6)
Geometric parameters (Å, º) top
O1—C121.381 (2)C9—C101.387 (2)
O1—C141.428 (2)C10—C111.404 (2)
O2—C111.3826 (18)C11—C121.385 (2)
O2—C151.429 (2)C12—C131.393 (2)
O3—C101.363 (2)C6—H60.9306
O3—C161.425 (2)C7—H7B0.9702
O4—C221.255 (2)C7—H7A0.9705
O5—C221.253 (2)C9—H90.9300
N1—C21.359 (2)C13—H130.9298
N1—C61.358 (2)C14—H14A0.9599
N2—C21.327 (2)C14—H14B0.9600
N3—C21.336 (2)C14—H14C0.9602
N3—C41.347 (2)C15—H15A0.9606
N4—C41.326 (2)C15—H15B0.9603
N1—H10.8838C15—H15C0.9600
N2—H2B0.8798C16—H16B0.9602
N2—H2A0.8838C16—H16C0.9604
N4—H4A0.8821C16—H16A0.9599
N4—H4B0.8769C17—C181.385 (2)
N5—C211.344 (2)C18—C191.383 (3)
N5—C171.340 (2)C19—C201.386 (2)
C4—C51.440 (2)C20—C211.384 (2)
C5—C61.351 (2)C21—C221.520 (2)
C5—C71.500 (2)C17—H170.9300
C7—C81.524 (2)C18—H180.9298
C8—C91.397 (2)C19—H190.9301
C8—C131.383 (2)C20—H200.9300
O1···O22.8568 (17)C11···H14A3.0654
O1···C153.231 (2)C11···H7Aii2.8326
O1···C16i3.349 (2)C12···H15A2.8795
O2···O32.6443 (17)C13···H18vii2.9832
O2···C142.899 (3)C14···H19xiii3.0778
O2···O12.8568 (17)C14···H15A3.0507
O3···O22.6443 (17)C15···H14A2.8712
O3···C6ii3.4012 (18)C15···H17ii2.9470
O3···C17ii3.141 (2)C16···H92.5185
O4···N2iii2.8693 (19)C17···H62.9689
O4···N4iv2.8412 (18)C18···H4Axii3.0848
O5···N12.7308 (19)C18···H16Aiv2.9905
O5···N52.7047 (19)C19···H16Aiv2.9696
O5···C23.200 (2)C19···H9iv3.0539
O5···N2iii3.1021 (19)C20···H9iv2.9316
O5···N22.7982 (19)C21···H13.0193
O1···H16Ci2.8871C22···H12.8163
O1···H15A2.6770C22···H2Aiii2.6049
O2···H14C2.8591C22···H15Bvi2.9407
O2···H17ii2.7965H1···O51.9244
O2···H14A2.5595H1···N52.3897
O2···H7Aii2.6861H1···C213.0193
O3···H6ii2.7319H1···C222.8163
O3···H17ii2.4857H1···H2B2.2084
O4···H20v2.8471H2A···O4iii1.9971
O4···H2Aiii1.9971H2A···C22iii2.6049
O4···H15Bvi2.7447H2A···O5iii2.6427
O4···H202.5256H2B···O5iii2.8930
O4···H4Biv2.1403H2B···H12.2084
O5···H2Aiii2.6427H2B···O52.0209
O5···H2B2.0209H4A···C18vii3.0848
O5···H11.9244H4A···C4viii3.0296
O5···H2Biii2.8930H4A···N3viii2.1187
N1···N53.0441 (19)H4A···C2viii3.0287
N1···O52.7308 (19)H4A···H4Aviii2.4891
N2···O5iii3.1021 (19)H4B···C72.6252
N2···C22iii3.338 (2)H4B···C82.9246
N2···O52.7982 (19)H4B···O4x2.1403
N2···O4iii2.8693 (19)H4B···H7B2.2651
N3···C19vii3.265 (2)H6···N52.7626
N3···N4viii2.9966 (18)H6···C172.9689
N3···C17ix3.3975 (19)H6···O3ii2.7319
N4···C20ix3.214 (2)H6···H172.4854
N4···O4x2.8412 (18)H6···H7A2.3487
N4···C83.2846 (19)H7A···O2ii2.6861
N4···C18vii3.286 (2)H7A···H62.3487
N4···N3viii2.9966 (18)H7A···C11ii2.8326
N5···C63.259 (2)H7B···H4B2.2651
N5···O52.7047 (19)H7B···N42.7777
N5···N13.0441 (19)H7B···H92.5251
N3···H19vii2.8002H7B···H20x2.3369
N3···H4Aviii2.1187H9···C162.5185
N4···H7B2.7777H9···C19x3.0539
N4···H18vii2.9470H9···C20x2.9316
N5···H12.3897H9···H7B2.5251
N5···H62.7626H9···H16A2.3998
C2···O53.200 (2)H9···H16C2.2217
C2···C14vi3.522 (3)H13···C52.5543
C2···C17ix3.544 (2)H13···C42.8679
C4···C133.329 (2)H13···H14Bvi2.5355
C4···C21ix3.423 (2)H14A···C152.8712
C4···C20ix3.512 (2)H14A···C113.0654
C6···N53.259 (2)H14A···O22.5595
C6···O3ii3.4012 (18)H14A···H15A2.5274
C8···N43.2846 (19)H14B···H13vi2.5355
C8···C10ii3.549 (2)H14C···O22.8591
C10···C8ii3.549 (2)H14C···H19xiii2.5504
C13···C43.329 (2)H14C···C112.8554
C14···C2vi3.522 (3)H15A···C122.8795
C14···O22.899 (3)H15A···O12.6770
C14···C153.444 (4)H15A···C143.0507
C15···O13.231 (2)H15A···H14A2.5274
C15···C143.444 (4)H15B···O4vi2.7447
C16···O1xi3.349 (2)H15B···C22vi2.9407
C16···C19x3.584 (2)H16A···C19x2.9696
C17···N3ix3.3975 (19)H16A···H92.3998
C17···O3ii3.141 (2)H16A···C92.7962
C17···C2ix3.544 (2)H16A···C18x2.9905
C18···N4xii3.286 (2)H16C···O1xi2.8871
C19···N3xii3.265 (2)H16C···C92.6959
C19···C16iv3.584 (2)H16C···H92.2217
C20···N4ix3.214 (2)H17···H62.4854
C20···C4ix3.512 (2)H17···O2ii2.7965
C21···C4ix3.423 (2)H17···O3ii2.4857
C22···N2iii3.338 (2)H17···C15ii2.9470
C2···H4Aviii3.0287H18···N4xii2.9470
C4···H132.8679H18···C13xii2.9832
C4···H4Aviii3.0296H19···N3xii2.8002
C5···H132.5543H19···C14xiii3.0778
C7···H4B2.6252H19···H14Cxiii2.5504
C8···H4B2.9246H20···O42.5256
C9···H16A2.7962H20···H7Biv2.3369
C9···H16C2.6959H20···O4v2.8471
C11···H14C2.8554
C12—O1—C14116.33 (16)C8—C7—H7B108.66
C11—O2—C15113.92 (12)H7A—C7—H7B107.61
C10—O3—C16117.20 (13)C8—C7—H7A108.69
C2—N1—C6119.87 (14)C10—C9—H9119.75
C2—N3—C4118.52 (14)C8—C9—H9119.69
C2—N1—H1116.97C8—C13—H13119.62
C6—N1—H1122.87C12—C13—H13119.64
C2—N2—H2A120.56O1—C14—H14B109.48
H2A—N2—H2B119.60O1—C14—H14C109.46
C2—N2—H2B118.40O1—C14—H14A109.46
H4A—N4—H4B119.60H14A—C14—H14C109.52
C4—N4—H4A116.20H14B—C14—H14C109.45
C4—N4—H4B121.58H14A—C14—H14B109.45
C17—N5—C21117.35 (14)O2—C15—H15A109.49
N2—C2—N3119.92 (14)O2—C15—H15B109.46
N1—C2—N3121.87 (14)H15A—C15—H15B109.42
N1—C2—N2118.21 (14)H15A—C15—H15C109.47
N4—C4—C5121.38 (14)O2—C15—H15C109.51
N3—C4—N4116.74 (14)H15B—C15—H15C109.48
N3—C4—C5121.86 (14)O3—C16—H16B109.52
C4—C5—C6115.90 (14)O3—C16—H16C109.41
C4—C5—C7121.75 (14)O3—C16—H16A109.49
C6—C5—C7122.32 (14)H16A—C16—H16C109.50
N1—C6—C5121.73 (14)H16B—C16—H16C109.45
C5—C7—C8114.30 (13)H16A—C16—H16B109.45
C7—C8—C13122.39 (14)N5—C17—C18123.71 (16)
C9—C8—C13118.92 (13)C17—C18—C19118.32 (16)
C7—C8—C9118.64 (14)C18—C19—C20118.74 (16)
C8—C9—C10120.56 (15)C19—C20—C21119.22 (16)
O3—C10—C9124.86 (15)N5—C21—C20122.62 (15)
O3—C10—C11114.79 (13)N5—C21—C22116.73 (14)
C9—C10—C11120.35 (15)C20—C21—C22120.65 (14)
C10—C11—C12118.74 (14)O4—C22—O5125.62 (15)
O2—C11—C10118.93 (14)O4—C22—C21117.18 (14)
O2—C11—C12122.26 (14)O5—C22—C21117.20 (14)
O1—C12—C11122.04 (14)N5—C17—H17118.19
O1—C12—C13117.24 (14)C18—C17—H17118.11
C11—C12—C13120.66 (15)C17—C18—H18120.83
C8—C13—C12120.74 (15)C19—C18—H18120.85
C5—C6—H6119.16C18—C19—H19120.64
N1—C6—H6119.11C20—C19—H19120.62
C5—C7—H7A108.70C19—C20—H20120.42
C5—C7—H7B108.69C21—C20—H20120.36
C14—O1—C12—C1155.3 (2)C7—C8—C9—C10177.28 (14)
C14—O1—C12—C13−127.54 (19)C13—C8—C9—C10−0.1 (2)
C15—O2—C11—C10−105.07 (17)C7—C8—C13—C12−177.29 (15)
C15—O2—C11—C1278.1 (2)C9—C8—C13—C120.0 (2)
C16—O3—C10—C9−7.5 (2)C8—C9—C10—C111.0 (2)
C16—O3—C10—C11173.07 (15)C8—C9—C10—O3−178.44 (15)
C6—N1—C2—N3−4.9 (2)C9—C10—C11—O2−178.65 (14)
C6—N1—C2—N2175.31 (13)O3—C10—C11—C12177.75 (15)
C2—N1—C6—C52.7 (2)C9—C10—C11—C12−1.7 (2)
C4—N3—C2—N12.1 (2)O3—C10—C11—O20.8 (2)
C4—N3—C2—N2−178.08 (13)C10—C11—C12—C131.6 (2)
C2—N3—C4—N4−178.97 (13)O2—C11—C12—O1−4.5 (2)
C2—N3—C4—C52.7 (2)C10—C11—C12—O1178.69 (15)
C17—N5—C21—C201.9 (2)O2—C11—C12—C13178.43 (15)
C21—N5—C17—C180.0 (2)C11—C12—C13—C8−0.8 (3)
C17—N5—C21—C22−178.53 (13)O1—C12—C13—C8−177.98 (15)
N4—C4—C5—C6177.17 (13)N5—C17—C18—C19−1.6 (2)
N3—C4—C5—C7173.50 (13)C17—C18—C19—C201.3 (2)
N3—C4—C5—C6−4.5 (2)C18—C19—C20—C210.5 (2)
N4—C4—C5—C7−4.8 (2)C19—C20—C21—C22178.27 (14)
C6—C5—C7—C8109.13 (16)C19—C20—C21—N5−2.2 (2)
C7—C5—C6—N1−176.29 (13)N5—C21—C22—O4170.51 (13)
C4—C5—C7—C8−68.79 (18)C20—C21—C22—O4−9.9 (2)
C4—C5—C6—N11.8 (2)C20—C21—C22—O5170.47 (14)
C5—C7—C8—C13−14.7 (2)N5—C21—C22—O5−9.1 (2)
C5—C7—C8—C9168.05 (14)
Symmetry codes: (i) x+1, y, z; (ii) −x, −y+1, −z; (iii) −x+2, −y+2, −z+1; (iv) x+1, y+1, z; (v) −x+2, −y+3, −z+1; (vi) −x+1, −y+1, −z; (vii) x, y−1, z; (viii) −x+1, −y+1, −z+1; (ix) −x+1, −y+2, −z+1; (x) x−1, y−1, z; (xi) x−1, y, z; (xii) x, y+1, z; (xiii) −x+1, −y+2, −z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O50.881.922.7308 (19)151
N1—H1···N50.882.393.0441 (19)131
N2—H2A···O4iii0.882.002.8693 (19)169
N2—H2B···O50.882.022.7982 (19)147
N4—H4A···N3viii0.882.122.9966 (18)173
N4—H4B···O4x0.882.142.8412 (18)137
C14—H14A···O20.962.562.899 (3)101
C17—H17···O3ii0.932.493.141 (2)128
Symmetry codes: (ii) −x, −y+1, −z; (iii) −x+2, −y+2, −z+1; (viii) −x+1, −y+1, −z+1; (x) x−1, y−1, z.
(II) 2-amino-4,6-dimethylpyrimidin-1-ium pyridine-2-carboxylate hemihydrate top
Crystal data top
C6H10N3+·C6H4NO2−·0.5H2OF(000) = 1080
Mr = 255.28Dx = 1.355 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2204 reflections
a = 15.7666 (4) Åθ = 3.3–26.0°
b = 8.7980 (1) ŵ = 0.10 mm−1
c = 18.5038 (4) ÅT = 120 K
β = 102.740 (1)°Block, colourless
V = 2503.55 (9) Å30.4 × 0.2 × 0.1 mm
Z = 8
Data collection top
Nonius KappaCCD area-detector
diffractometer		2204 reflections with I > 2σ(I)
Radiation source: Bruker Nonius FR591 rotating anodeRint = 0.026
Graphite monochromatorθmax = 26.0°, θmin = 3.3°
ϕ and ω scansh = −19→19
16549 measured reflectionsk = −10→10
2451 independent reflectionsl = −22→22
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.060H-atom parameters constrained
wR(F2) = 0.143 w = 1/[σ2(Fo2) + (0.0834P)2 + 1.0121P]
where P = (Fo2 + 2Fc2)/3
S = 1.26(Δ/σ)max < 0.001
2451 reflectionsΔρmax = 0.78 e Å−3
171 parametersΔρmin = −0.82 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001Fc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.060 (4)
Crystal data top
C6H10N3+·C6H4NO2−·0.5H2OV = 2503.55 (9) Å3
Mr = 255.28Z = 8
Monoclinic, C2/cMo Kα radiation
a = 15.7666 (4) ŵ = 0.10 mm−1
b = 8.7980 (1) ÅT = 120 K
c = 18.5038 (4) Å0.4 × 0.2 × 0.1 mm
β = 102.740 (1)°
Data collection top
Nonius KappaCCD area-detector
diffractometer		2204 reflections with I > 2σ(I)
16549 measured reflectionsRint = 0.026
2451 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0600 restraints
wR(F2) = 0.143H-atom parameters constrained
S = 1.26Δρmax = 0.78 e Å−3
2451 reflectionsΔρmin = −0.82 e Å−3
171 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All e.s.d.'s are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
N1−0.00471 (7)0.71894 (12)0.48590 (6)0.0174 (3)
N20.13114 (7)0.79667 (13)0.54980 (6)0.0195 (3)
N30.01063 (8)0.89924 (13)0.58351 (6)0.0190 (3)
C20.04584 (9)0.80507 (14)0.54005 (7)0.0172 (4)
C4−0.07541 (9)0.90978 (15)0.56940 (8)0.0197 (4)
C5−0.13012 (9)0.82756 (16)0.51217 (8)0.0208 (4)
C6−0.09286 (9)0.72949 (15)0.47096 (8)0.0189 (4)
C7−0.11364 (10)1.01425 (18)0.61770 (8)0.0251 (4)
C8−0.14136 (9)0.63004 (17)0.41025 (8)0.0233 (4)
O10.06155 (6)0.55173 (12)0.39158 (6)0.0251 (3)
O20.19643 (7)0.59392 (13)0.45783 (6)0.0264 (3)
N40.26418 (7)0.48590 (13)0.34444 (6)0.0192 (3)
C90.17995 (9)0.46233 (15)0.34366 (7)0.0176 (4)
C100.12663 (10)0.37113 (17)0.29108 (8)0.0227 (4)
C110.16146 (11)0.30355 (17)0.23621 (8)0.0260 (5)
C120.24774 (11)0.32921 (16)0.23601 (8)0.0259 (5)
C130.29686 (10)0.41996 (16)0.29116 (8)0.0227 (4)
C140.14375 (9)0.54243 (15)0.40325 (8)0.0183 (4)
O1W0.000000.7153 (2)0.250000.0556 (7)
H10.020200.655500.460200.0210*
H2A0.164700.851900.584300.0230*
H2B0.154500.735800.521800.0230*
H5−0.191400.840000.502500.0250*
H7A−0.134800.954500.654800.0300*
H7B−0.162101.070900.587200.0300*
H7C−0.069001.085700.642700.0300*
H8A−0.115400.638500.366900.0280*
H8B−0.202300.662100.396800.0280*
H8C−0.138200.524300.427200.0280*
H100.067500.355300.292700.0270*
H110.126500.240900.199600.0310*
H120.273100.285600.198800.0310*
H130.356400.436100.291100.0270*
H1W0.016100.644100.292000.0670*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0181 (6)0.0184 (6)0.0161 (6)0.0009 (4)0.0048 (5)−0.0014 (4)
N20.0178 (6)0.0228 (6)0.0180 (6)−0.0007 (4)0.0043 (5)−0.0047 (4)
N30.0214 (6)0.0192 (6)0.0173 (6)0.0005 (5)0.0065 (5)−0.0002 (4)
C20.0217 (7)0.0156 (7)0.0146 (7)0.0000 (5)0.0049 (5)0.0029 (5)
C40.0235 (7)0.0180 (7)0.0197 (7)0.0010 (5)0.0091 (6)0.0043 (5)
C50.0181 (7)0.0219 (7)0.0231 (7)0.0004 (5)0.0060 (6)0.0026 (6)
C60.0196 (7)0.0187 (7)0.0182 (7)−0.0004 (5)0.0038 (5)0.0046 (5)
C70.0260 (7)0.0266 (8)0.0257 (8)0.0018 (6)0.0121 (6)−0.0033 (6)
C80.0217 (7)0.0241 (8)0.0228 (7)−0.0015 (6)0.0024 (6)−0.0014 (6)
O10.0182 (5)0.0321 (6)0.0247 (6)0.0019 (4)0.0040 (4)−0.0080 (4)
O20.0205 (5)0.0359 (6)0.0224 (6)−0.0001 (4)0.0038 (4)−0.0115 (4)
N40.0223 (6)0.0184 (6)0.0180 (6)0.0009 (5)0.0065 (5)−0.0003 (4)
C90.0208 (7)0.0169 (7)0.0148 (7)0.0020 (5)0.0031 (5)0.0012 (5)
C100.0228 (7)0.0239 (7)0.0201 (7)0.0002 (6)0.0018 (6)−0.0016 (5)
C110.0358 (9)0.0229 (8)0.0179 (7)−0.0016 (6)0.0027 (6)−0.0044 (5)
C120.0399 (9)0.0212 (7)0.0199 (8)0.0010 (6)0.0139 (6)−0.0017 (6)
C130.0269 (8)0.0205 (7)0.0237 (7)0.0004 (6)0.0119 (6)0.0013 (5)
C140.0196 (7)0.0174 (7)0.0176 (7)0.0009 (5)0.0036 (5)0.0005 (5)
O1W0.0824 (16)0.0339 (10)0.0387 (11)0.0000−0.0120 (10)0.0000
Geometric parameters (Å, º) top
O1—C141.2687 (18)C6—C81.494 (2)
O2—C141.2430 (18)C5—H50.9493
O1W—H1W0.9868C7—H7C0.9803
O1W—H1Wi0.9868C7—H7A0.9798
N1—C21.3642 (17)C7—H7B0.9801
N1—C61.3591 (18)C8—H8A0.9805
N2—C21.3190 (18)C8—H8C0.9795
N3—C41.3270 (19)C8—H8B0.9794
N3—C21.3558 (18)C9—C141.5218 (19)
N1—H10.8799C9—C101.392 (2)
N2—H2A0.8801C10—C111.390 (2)
N2—H2B0.8804C11—C121.380 (2)
N4—C131.3409 (19)C12—C131.389 (2)
N4—C91.3410 (18)C10—H100.9496
C4—C51.409 (2)C11—H110.9497
C4—C71.498 (2)C12—H120.9500
C5—C61.367 (2)C13—H130.9497
O1···O1W2.9588 (14)C9···H12vii3.0840
O1···N12.6657 (15)C10···H7Aiii3.0282
O1···C83.3640 (18)C10···H1W2.9695
O1···O1W2.9588 (14)C13···H8Bvi2.9928
O1W···O12.9588 (14)C13···H8Avi3.0257
O1W···O1i2.9588 (14)C13···H11vii3.0612
O2···N22.8125 (16)C13···H2Aii3.0151
O2···N2ii2.9166 (16)C14···H2B2.7516
O2···N42.7267 (16)C14···H12.6077
O2···C8iii3.3955 (18)C14···H1W2.6946
O1···H102.5335H1···C142.6077
O1···H8A2.8307H1···O11.7989
O1···H1W1.9967H1···H2B2.2842
O1···H11.7989H1···O22.8407
O1W···H7Civ2.6904H1···H8A2.4384
O1W···H7Cv2.6904H1W···C142.6946
O2···H8Ciii2.7041H1W···C102.9695
O2···H12.8407H1W···C93.0093
O2···H2B1.9343H1W···O11.9967
O2···H7Bvi2.8968H2A···O2ii2.5262
O2···H2Bii2.7422H2A···C13ii3.0151
O2···H5vi2.8560H2A···H11viii2.4795
O2···H2Aii2.5262H2A···C9ii3.0012
N1···O12.6657 (15)H2A···N4ii2.0929
N1···C143.4363 (18)H2B···H8Ciii2.5100
N2···N4ii2.9645 (16)H2B···O2ii2.7422
N2···O22.8125 (16)H2B···H12.2842
N2···C4v3.3841 (18)H2B···C142.7516
N2···O2ii2.9166 (16)H2B···O21.9343
N3···C2v3.4482 (17)H5···H8B2.4812
N4···O22.7267 (16)H5···O2ix2.8560
N4···C12vii3.3543 (18)H5···H7B2.5450
N4···N2ii2.9645 (16)H5···H5xi2.4198
N2···H8Ciii2.8543H7A···C10iii3.0282
N2···H11viii2.8084H7B···N2v2.9271
N2···H7Bv2.9271H7B···O2ix2.8968
N3···H11viii2.7823H7B···H52.5450
N4···H12vii2.7804H7C···O1Wxii2.6904
N4···H2Aii2.0929H7C···O1Wv2.6904
C2···C4v3.3210 (19)H8A···H12.4384
C2···N3v3.4482 (17)H8A···O12.8307
C4···C2v3.3210 (19)H8A···C13ix3.0257
C4···N2v3.3841 (18)H8B···H52.4812
C6···C14iii3.551 (2)H8B···C13ix2.9928
C8···C13ix3.371 (2)H8C···H2Biii2.5100
C8···O13.3640 (18)H8C···N2iii2.8543
C8···O2iii3.3955 (18)H8C···O2iii2.7040
C11···C13x3.496 (2)H10···O12.5335
C12···N4x3.3543 (18)H10···H10i2.3546
C13···C8vi3.371 (2)H11···N3xiii2.7823
C13···C11vii3.496 (2)H11···C2xiii2.9734
C14···C6iii3.551 (2)H11···H2Axiii2.4795
C14···N13.4363 (18)H11···C13x3.0612
C2···H11viii2.9734H11···N2xiii2.8084
C9···H2Aii3.0012H12···N4x2.7804
C9···H1W3.0093H12···C9x3.0840
H1W—O1W—H1Wi101.19H7B—C7—H7C109.45
C2—N1—C6121.13 (12)C6—C8—H8B109.46
C2—N3—C4117.42 (12)C6—C8—H8C109.51
C2—N1—H1119.42H8A—C8—H8C109.46
C6—N1—H1119.45H8B—C8—H8C109.43
H2A—N2—H2B120.01C6—C8—H8A109.50
C2—N2—H2A120.00H8A—C8—H8B109.47
C2—N2—H2B119.99N4—C9—C14116.70 (12)
C9—N4—C13117.73 (12)C10—C9—C14120.55 (13)
N1—C2—N2118.83 (12)N4—C9—C10122.74 (13)
N1—C2—N3121.72 (13)C9—C10—C11118.84 (15)
N2—C2—N3119.45 (12)C10—C11—C12118.72 (14)
C5—C4—C7120.20 (13)C11—C12—C13118.84 (14)
N3—C4—C7116.99 (12)N4—C13—C12123.12 (15)
N3—C4—C5122.80 (13)O1—C14—O2126.11 (14)
C4—C5—C6118.43 (13)O2—C14—C9117.86 (13)
C5—C6—C8125.26 (13)O1—C14—C9116.03 (12)
N1—C6—C8116.34 (12)C9—C10—H10120.56
N1—C6—C5118.40 (13)C11—C10—H10120.60
C6—C5—H5120.82C12—C11—H11120.70
C4—C5—H5120.75C10—C11—H11120.58
C4—C7—H7B109.49C11—C12—H12120.57
H7A—C7—H7B109.49C13—C12—H12120.59
H7A—C7—H7C109.48N4—C13—H13118.45
C4—C7—H7C109.48C12—C13—H13118.43
C4—C7—H7A109.44
C6—N1—C2—N2−176.44 (12)C7—C4—C5—C6−177.79 (13)
C6—N1—C2—N33.15 (19)C4—C5—C6—C8177.75 (13)
C2—N1—C6—C5−0.75 (19)C4—C5—C6—N1−1.7 (2)
C2—N1—C6—C8179.76 (12)N4—C9—C10—C11−1.2 (2)
C4—N3—C2—N1−2.83 (18)C14—C9—C10—C11178.09 (13)
C4—N3—C2—N2176.76 (12)N4—C9—C14—O2−16.38 (18)
C2—N3—C4—C50.3 (2)C10—C9—C14—O1−16.52 (19)
C2—N3—C4—C7−179.95 (13)C10—C9—C14—O2164.34 (13)
C9—N4—C13—C12−0.1 (2)N4—C9—C14—O1162.77 (12)
C13—N4—C9—C101.1 (2)C9—C10—C11—C120.1 (2)
C13—N4—C9—C14−178.13 (12)C10—C11—C12—C130.8 (2)
N3—C4—C5—C62.0 (2)C11—C12—C13—N4−0.9 (2)
Symmetry codes: (i) −x, y, −z+1/2; (ii) −x+1/2, −y+3/2, −z+1; (iii) −x, −y+1, −z+1; (iv) x, −y+2, z−1/2; (v) −x, −y+2, −z+1; (vi) x+1/2, y−1/2, z; (vii) −x+1/2, y+1/2, −z+1/2; (viii) x, −y+1, z+1/2; (ix) x−1/2, y+1/2, z; (x) −x+1/2, y−1/2, −z+1/2; (xi) −x−1/2, −y+3/2, −z+1; (xii) x, −y+2, z+1/2; (xiii) x, −y+1, z−1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.881.802.6657 (15)168
O1W—H1W···O10.992.002.9588 (14)164
N2—H2A···O2ii0.882.532.9166 (16)108
N2—H2A···N4ii0.882.092.9645 (16)170
N2—H2B···O20.881.932.8125 (16)175
Symmetry code: (ii) −x+1/2, −y+3/2, −z+1.

Experimental details

(I)(II)
Crystal data
Chemical formulaC14H19N4O3+·C6H4NO2−C6H10N3+·C6H4NO2−·0.5H2O
Mr413.43255.28
Crystal system, space groupTriclinic, P1Monoclinic, C2/c
Temperature (K)120120
a, b, c (Å)9.0642 (3), 10.2730 (3), 12.1188 (4)15.7666 (4), 8.7980 (1), 18.5038 (4)
α, β, γ (°)108.051 (17), 98.741 (2), 107.517 (2)90, 102.740 (1), 90
V (Å3)985.03 (14)2503.55 (9)
Z28
Radiation typeMo KαMo Kα
µ (mm−1)0.100.10
Crystal size (mm)0.22 × 0.20 × 0.160.4 × 0.2 × 0.1
Data collection
DiffractometerNonius KappaCCD area-detector
diffractometer		Nonius KappaCCD area-detector
diffractometer
Absorption correction––
No. of measured, independent and
observed [I > 2σ(I)] reflections		17816, 4537, 3758 16549, 2451, 2204
Rint0.0360.026
(sin θ/λ)max (Å−1)0.6530.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.141, 1.13 0.060, 0.143, 1.26
No. of reflections45372451
No. of parameters275171
No. of restraints20
H-atom treatmentH-atom parameters constrainedH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.47, −0.470.78, −0.82

Computer programs: DENZO (Otwinowski & Minor, 1997) and COLLECT (Nonius, 1998), DENZO and COLLECT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), PLATON.

Selected geometric parameters (Å, º) for (I) top
O1—C121.381 (2)O3—C101.363 (2)
O1—C141.428 (2)O3—C161.425 (2)
O2—C111.3826 (18)O4—C221.255 (2)
O2—C151.429 (2)O5—C221.253 (2)
C2—N1—C6119.87 (14)N1—C2—N3121.87 (14)
C2—N3—C4118.52 (14)N1—C2—N2118.21 (14)
N2—C2—N3119.92 (14)N3—C4—N4116.74 (14)
Hydrogen-bond geometry (Å, º) for (I) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O50.881.922.7308 (19)151
N1—H1···N50.882.393.0441 (19)131
N2—H2A···O4i0.882.002.8693 (19)169
N2—H2B···O50.882.022.7982 (19)147
N4—H4A···N3ii0.882.122.9966 (18)173
N4—H4B···O4iii0.882.142.8412 (18)137
C14—H14A···O20.962.562.899 (3)101
C17—H17···O3iv0.932.493.141 (2)128
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x−1, y−1, z; (iv) −x, −y+1, −z.
Selected geometric parameters (Å, º) for (II) top
O1—C141.2687 (18)N3—C41.3270 (19)
O2—C141.2430 (18)N3—C21.3558 (18)
N1—C21.3642 (17)N4—C131.3409 (19)
N1—C61.3591 (18)N4—C91.3410 (18)
N2—C21.3190 (18)
C2—N1—C6121.13 (12)N1—C6—C8116.34 (12)
C2—N3—C4117.42 (12)N1—C6—C5118.40 (13)
C9—N4—C13117.73 (12)N4—C9—C14116.70 (12)
N1—C2—N2118.83 (12)N4—C9—C10122.74 (13)
N1—C2—N3121.72 (13)N4—C13—C12123.12 (15)
N2—C2—N3119.45 (12)O1—C14—O2126.11 (14)
N3—C4—C7116.99 (12)O2—C14—C9117.86 (13)
N3—C4—C5122.80 (13)O1—C14—C9116.03 (12)
Hydrogen-bond geometry (Å, º) for (II) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O10.881.802.6657 (15)168
O1W—H1W···O10.992.002.9588 (14)164
N2—H2A···O2i0.882.532.9166 (16)108
N2—H2A···N4i0.882.092.9645 (16)170
N2—H2B···O20.881.932.8125 (16)175
Symmetry code: (i) −x+1/2, −y+3/2, −z+1.
 

Acknowledgements

MH thanks the Council of Scientific and Industrial Research (CSIR), India, for the award of a Senior Research Fellowship (SRF) [reference No. 9/475(123)/2004-EMR-I]. DL thanks the EPSRC National Crystallographic Service, Southampton, England, for the X-ray data collection.

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ISSN: 2053-2296
Volume 62| Part 2| February 2006| Pages o107-o110
doi:10.1107/S0108270105037856
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