organic compounds
4-Aminopyridinium 4-carboxybutanoate
aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bBiomedical Structural Biology, School of Biological Sciences, Nanyang Technological University, Singapore 138673
*Correspondence e-mail: hkfun@usm.my
The 5H7N2+·C5H7O4−, contains two 4-aminopyridinium cations and two 4-carboxybutanoate anions. Each 4-aminopyridinium cation is planar, with a maximum deviation of 0.005 (2) Å. Both 4-carboxybutanoate anions adopt an extended conformation. In the the cations and anions are linked via N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane.
of the title salt, CRelated literature
For the biological activity of 4-aminopyridine, see: Schwid et al. (1997). For determinations of 4-aminopyridine, see: Chao & Schempp (1977); Anderson et al. (2005). For conformations of 4-carboxybutanoate (hydrogen glutarate) anions, see: Saraswathi et al. (2001).
Experimental
Crystal data
|
Refinement
|
Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536810028734/wn2401sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810028734/wn2401Isup2.hkl
A hot methanol solution (20 ml) of 4-aminopyridine (0.0471 g, Aldrich) and glutaric acid (0.0661 g, Merck) was warmed for half an hour over a water bath. The mixture was cooled slowly and kept at room temperature. Colourless crystals were obtained after a few days.
Oxygen-bound H atoms were located in a difference map [O—H = 0.8903 and 0.9176 Å]. Nitrogen- and carbon-bound H atoms were positioned geometrically [N—H = 0.86 Å and C—H = 0.93–0.97 Å]. All hydrogen atoms were refined using a riding model, with Uiso(H) = 1.2 Ueq(C).
4-Aminopyridine (fampridine) is used in the treatment of neurological ailments, such as multiple sclerosis (MS), with tests showing that fampridine improves motor function in MS patients (Schwid et al., 1997). The room temperature
of 4-aminopyridine was reported many years ago (Chao & Schempp, 1977); a redetermination at low temperature has been reported more recently (Anderson et al., 2005). Aliphatic dicarboxylic acids, HOOC(CH2)nCOOH, exhibit interesting complexing properties. This is due to the flexibility of the ligand which may be completely or only partially deprotonated. Glutaric acid (1,3-propanedicarboxylic acid) is a white crystalline solid which is very soluble in water. The compound is a useful building block for polymers, an intermediate in chemical synthesis and it is used in the manufacture of an antiretroviral drug. The compound is also used in solder The present study has been carried out to study the hydrogen bonding patterns present in the of 4-aminopyridinium 4-carboxybutanoate.The
of the title compound consists of two crystallographically independent 4-aminopyridinium cations (A and B) and 4-carboxybutanoate (hydrogen glutarate) anions (A and B) (Fig. 1). Each 4-aminopyridinium cation is planar, with a maximum deviation of 0.005 (2) Å for atom C7A in cation A and 0.005 (2) Å for atom C9B in cation B. In the cations, protonation at atoms N1A and N1B lead to a slight increase in the C6A—N1A—C10A [120.06 (16)°] and C6B—N1B—C10B [120.21 (16)°] angles compared to those observed in the unprotonated structure of 4-aminopyridine (Anderson et al., 2005). The conformations of the 4-carboxybutanoate anions can be described by the two torsion angles C1A—C2A—C3A—C4A of 175.44 (15)° and C2A—C3A—C4A—C5A of 174.42 (15)° in anion A; C1B—C2B—C3B—C4B of -175.99 (14)° and C2B—C3B—C4B—C5B of -176.94 (15)° in anion B. These torsion angles indicate that both anions adopt fully extended conformations (Saraswathi et al., 2001).In the
(Fig. 2), the cations and anions are linked via O1A—H1O1···O1B, N1A—H1AA···O1B, N1A—H1AA···O2B, N2A—H2AC···O2A, N2A—H2AD···O4B, O3B—H1O3···O3A, C10A—H10A···O4B and C7A—H7AA···03B intermolecular hydrogen bonds (Table 1), forming a two-dimensional network parallel to the bc-plane.The
is a twin, with BASF = 0.3214 (15).For the biological activity of 4-aminopyridine, see: Schwid et al. (1997). For
determinations of 4-aminopyridine, see: Chao & Schempp (1977); Anderson et al. (2005). For conformations of 4-carboxybutanoate (hydrogen glutarate) anions, see: Saraswathi et al. (2001).Data collection: APEX2 (Bruker, 2009); cell
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).Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius. | |
Fig. 2. The crystal packing, showing hydrogen-bonded (dashed lines) 2D networks parallel to to the bc-plane. H atoms not involved in the intermolecular interactions have been omitted for clarity. |
C5H7N2+·C5H7O4− | F(000) = 960 |
Mr = 226.23 | Dx = 1.368 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 8906 reflections |
a = 9.6159 (2) Å | θ = 2.5–30.1° |
b = 10.3065 (2) Å | µ = 0.11 mm−1 |
c = 22.6801 (5) Å | T = 296 K |
β = 102.143 (1)° | Block, colourless |
V = 2197.45 (8) Å3 | 0.35 × 0.26 × 0.21 mm |
Z = 8 |
Bruker SMART APEXII CCD area-detector diffractometer | 7931 independent reflections |
Radiation source: fine-focus sealed tube | 5556 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.000 |
φ and ω scans | θmax = 32.6°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −14→14 |
Tmin = 0.963, Tmax = 0.978 | k = −15→15 |
7931 measured reflections | l = −11→34 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.053 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.154 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0758P)2 + 0.2205P] where P = (Fo2 + 2Fc2)/3 |
7931 reflections | (Δ/σ)max < 0.001 |
290 parameters | Δρmax = 0.37 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
C5H7N2+·C5H7O4− | V = 2197.45 (8) Å3 |
Mr = 226.23 | Z = 8 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.6159 (2) Å | µ = 0.11 mm−1 |
b = 10.3065 (2) Å | T = 296 K |
c = 22.6801 (5) Å | 0.35 × 0.26 × 0.21 mm |
β = 102.143 (1)° |
Bruker SMART APEXII CCD area-detector diffractometer | 7931 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 5556 reflections with I > 2σ(I) |
Tmin = 0.963, Tmax = 0.978 | Rint = 0.000 |
7931 measured reflections |
R[F2 > 2σ(F2)] = 0.053 | 0 restraints |
wR(F2) = 0.154 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.37 e Å−3 |
7931 reflections | Δρmin = −0.20 e Å−3 |
290 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(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. |
x | y | z | Uiso*/Ueq | ||
O1A | 0.28193 (16) | 1.02435 (13) | 0.06872 (6) | 0.0516 (3) | |
H1O1 | 0.2530 | 1.0161 | 0.0289 | 0.077* | |
O2A | 0.41099 (16) | 0.95000 (13) | 0.15319 (5) | 0.0478 (3) | |
O3A | 0.76925 (16) | 0.49292 (13) | 0.05256 (5) | 0.0528 (4) | |
O4A | 0.74003 (16) | 0.55719 (12) | 0.14167 (5) | 0.0454 (3) | |
C1A | 0.3787 (2) | 0.94695 (15) | 0.09826 (7) | 0.0352 (3) | |
C2A | 0.4485 (2) | 0.85513 (16) | 0.06135 (7) | 0.0370 (3) | |
H2AA | 0.5028 | 0.9059 | 0.0381 | 0.044* | |
H2AB | 0.3745 | 0.8103 | 0.0330 | 0.044* | |
C3A | 0.5465 (2) | 0.75453 (16) | 0.09724 (7) | 0.0352 (3) | |
H3AA | 0.6264 | 0.7976 | 0.1230 | 0.042* | |
H3AB | 0.4955 | 0.7064 | 0.1227 | 0.042* | |
C4A | 0.60070 (19) | 0.66165 (16) | 0.05536 (7) | 0.0366 (3) | |
H4AA | 0.5202 | 0.6144 | 0.0322 | 0.044* | |
H4AB | 0.6415 | 0.7121 | 0.0271 | 0.044* | |
C5A | 0.7105 (2) | 0.56458 (15) | 0.08576 (7) | 0.0346 (3) | |
N1A | 0.28175 (17) | 0.87243 (15) | 0.83697 (7) | 0.0449 (4) | |
H1AA | 0.2264 | 0.9279 | 0.8486 | 0.054* | |
N2A | 0.53978 (18) | 0.60387 (16) | 0.78136 (7) | 0.0499 (4) | |
H2AC | 0.5341 | 0.5918 | 0.7434 | 0.060* | |
H2AD | 0.5987 | 0.5590 | 0.8072 | 0.060* | |
C6A | 0.3744 (2) | 0.80430 (19) | 0.87789 (8) | 0.0488 (4) | |
H6AA | 0.3778 | 0.8191 | 0.9186 | 0.059* | |
C7A | 0.4634 (2) | 0.71465 (18) | 0.86214 (8) | 0.0461 (4) | |
H7AA | 0.5268 | 0.6692 | 0.8915 | 0.055* | |
C8A | 0.45783 (19) | 0.69135 (17) | 0.79991 (8) | 0.0379 (3) | |
C9A | 0.3609 (2) | 0.76547 (17) | 0.75810 (7) | 0.0399 (4) | |
H9AA | 0.3548 | 0.7543 | 0.7169 | 0.048* | |
C10A | 0.2754 (2) | 0.85416 (19) | 0.77826 (8) | 0.0434 (4) | |
H10A | 0.2115 | 0.9027 | 0.7504 | 0.052* | |
O1B | 1.22169 (16) | −0.01002 (13) | 0.95900 (5) | 0.0527 (4) | |
O2B | 1.10552 (17) | 0.05354 (13) | 0.86994 (5) | 0.0494 (3) | |
O3B | 0.72084 (16) | 0.52422 (13) | 0.94174 (6) | 0.0532 (4) | |
H1O3 | 0.7347 | 0.5145 | 0.9828 | 0.080* | |
O4B | 0.76125 (17) | 0.44368 (13) | 0.85744 (5) | 0.0524 (3) | |
C1B | 1.12988 (19) | 0.06276 (15) | 0.92524 (7) | 0.0359 (3) | |
C2B | 1.05243 (19) | 0.16092 (15) | 0.95600 (7) | 0.0357 (3) | |
H2BA | 1.1223 | 0.2127 | 0.9831 | 0.043* | |
H2BB | 0.9966 | 0.1148 | 0.9803 | 0.043* | |
C3B | 0.9547 (2) | 0.25132 (15) | 0.91350 (7) | 0.0342 (3) | |
H3BA | 0.8792 | 0.2016 | 0.8884 | 0.041* | |
H3BB | 1.0079 | 0.2948 | 0.8874 | 0.041* | |
C4B | 0.89090 (19) | 0.35155 (16) | 0.94935 (7) | 0.0361 (3) | |
H4BA | 0.8441 | 0.3063 | 0.9773 | 0.043* | |
H4BB | 0.9677 | 0.4023 | 0.9731 | 0.043* | |
C5B | 0.7856 (2) | 0.44294 (16) | 0.91214 (7) | 0.0358 (3) | |
N1B | −0.04752 (17) | 0.37734 (15) | 0.17394 (7) | 0.0453 (4) | |
H1BA | −0.1137 | 0.4333 | 0.1619 | 0.054* | |
N2B | 0.26087 (18) | 0.10594 (16) | 0.23042 (7) | 0.0494 (4) | |
H2BC | 0.2914 | 0.0928 | 0.2684 | 0.059* | |
H2BD | 0.2946 | 0.0613 | 0.2046 | 0.059* | |
C6B | 0.0019 (2) | 0.35827 (19) | 0.23332 (8) | 0.0440 (4) | |
H6BA | −0.0348 | 0.4067 | 0.2611 | 0.053* | |
C7B | 0.1058 (2) | 0.26829 (17) | 0.25317 (7) | 0.0402 (4) | |
H7BA | 0.1392 | 0.2560 | 0.2943 | 0.048* | |
C8B | 0.16224 (19) | 0.19448 (17) | 0.21178 (7) | 0.0377 (3) | |
C9B | 0.1092 (2) | 0.21875 (18) | 0.14972 (8) | 0.0463 (4) | |
H9BA | 0.1444 | 0.1734 | 0.1206 | 0.056* | |
C10B | 0.0059 (2) | 0.30944 (19) | 0.13355 (8) | 0.0494 (5) | |
H10B | −0.0291 | 0.3250 | 0.0927 | 0.059* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1A | 0.0584 (8) | 0.0587 (8) | 0.0349 (6) | 0.0303 (7) | 0.0034 (6) | −0.0017 (6) |
O2A | 0.0626 (9) | 0.0535 (7) | 0.0270 (5) | 0.0165 (7) | 0.0085 (6) | −0.0009 (5) |
O3A | 0.0656 (9) | 0.0597 (8) | 0.0334 (6) | 0.0320 (7) | 0.0109 (6) | −0.0008 (6) |
O4A | 0.0568 (8) | 0.0485 (7) | 0.0289 (6) | 0.0187 (6) | 0.0043 (6) | −0.0008 (5) |
C1A | 0.0396 (9) | 0.0387 (8) | 0.0277 (7) | 0.0068 (7) | 0.0083 (6) | 0.0003 (6) |
C2A | 0.0420 (9) | 0.0428 (8) | 0.0262 (7) | 0.0128 (8) | 0.0073 (6) | 0.0014 (6) |
C3A | 0.0401 (8) | 0.0367 (7) | 0.0288 (7) | 0.0081 (6) | 0.0068 (7) | −0.0011 (6) |
C4A | 0.0397 (8) | 0.0421 (8) | 0.0274 (7) | 0.0105 (8) | 0.0056 (6) | −0.0012 (6) |
C5A | 0.0383 (8) | 0.0351 (7) | 0.0298 (7) | 0.0065 (7) | 0.0056 (6) | −0.0012 (6) |
N1A | 0.0506 (9) | 0.0441 (8) | 0.0422 (8) | 0.0090 (7) | 0.0148 (7) | −0.0026 (6) |
N2A | 0.0533 (10) | 0.0551 (9) | 0.0386 (8) | 0.0173 (8) | 0.0036 (7) | −0.0042 (7) |
C6A | 0.0620 (12) | 0.0484 (10) | 0.0347 (8) | 0.0055 (10) | 0.0071 (8) | −0.0039 (7) |
C7A | 0.0564 (12) | 0.0457 (9) | 0.0334 (8) | 0.0097 (9) | 0.0029 (8) | −0.0012 (7) |
C8A | 0.0392 (8) | 0.0369 (8) | 0.0362 (8) | 0.0018 (7) | 0.0048 (7) | −0.0005 (6) |
C9A | 0.0458 (10) | 0.0465 (9) | 0.0261 (7) | 0.0040 (7) | 0.0044 (7) | 0.0019 (6) |
C10A | 0.0456 (10) | 0.0477 (9) | 0.0375 (8) | 0.0034 (8) | 0.0102 (7) | 0.0027 (7) |
O1B | 0.0608 (8) | 0.0608 (8) | 0.0340 (6) | 0.0342 (7) | 0.0042 (6) | 0.0021 (6) |
O2B | 0.0653 (9) | 0.0533 (7) | 0.0293 (6) | 0.0242 (7) | 0.0094 (6) | 0.0018 (5) |
O3B | 0.0653 (9) | 0.0577 (8) | 0.0353 (6) | 0.0334 (7) | 0.0073 (6) | 0.0009 (6) |
O4B | 0.0659 (9) | 0.0579 (8) | 0.0288 (6) | 0.0227 (7) | −0.0008 (6) | −0.0005 (5) |
C1B | 0.0407 (9) | 0.0373 (8) | 0.0301 (7) | 0.0084 (7) | 0.0087 (7) | 0.0018 (6) |
C2B | 0.0406 (9) | 0.0380 (8) | 0.0281 (7) | 0.0122 (7) | 0.0063 (6) | 0.0011 (6) |
C3B | 0.0401 (8) | 0.0344 (7) | 0.0273 (7) | 0.0066 (6) | 0.0054 (7) | −0.0005 (6) |
C4B | 0.0398 (8) | 0.0389 (7) | 0.0279 (7) | 0.0095 (7) | 0.0032 (6) | −0.0035 (6) |
C5B | 0.0387 (9) | 0.0343 (7) | 0.0321 (7) | 0.0076 (7) | 0.0019 (6) | −0.0010 (6) |
N1B | 0.0458 (9) | 0.0450 (8) | 0.0424 (8) | 0.0103 (7) | 0.0030 (7) | 0.0035 (6) |
N2B | 0.0553 (10) | 0.0565 (9) | 0.0368 (8) | 0.0171 (8) | 0.0105 (7) | 0.0065 (7) |
C6B | 0.0468 (10) | 0.0480 (9) | 0.0368 (9) | 0.0012 (9) | 0.0078 (7) | −0.0046 (7) |
C7B | 0.0461 (10) | 0.0455 (9) | 0.0278 (7) | 0.0047 (8) | 0.0048 (7) | −0.0013 (6) |
C8B | 0.0406 (9) | 0.0390 (8) | 0.0342 (8) | 0.0033 (7) | 0.0095 (7) | 0.0019 (6) |
C9B | 0.0577 (12) | 0.0480 (9) | 0.0330 (8) | 0.0116 (9) | 0.0093 (8) | −0.0003 (7) |
C10B | 0.0588 (12) | 0.0554 (10) | 0.0325 (9) | 0.0105 (10) | 0.0062 (8) | 0.0045 (8) |
O1A—C1A | 1.299 (2) | O1B—C1B | 1.2823 (19) |
O1A—H1O1 | 0.8903 | O2B—C1B | 1.2303 (19) |
O2A—C1A | 1.2194 (18) | O3B—C5B | 1.310 (2) |
O3A—C5A | 1.269 (2) | O3B—H1O3 | 0.9176 |
O4A—C5A | 1.2423 (18) | O4B—C5B | 1.2133 (19) |
C1A—C2A | 1.511 (2) | C1B—C2B | 1.511 (2) |
C2A—C3A | 1.518 (2) | C2B—C3B | 1.516 (2) |
C2A—H2AA | 0.9700 | C2B—H2BA | 0.9700 |
C2A—H2AB | 0.9700 | C2B—H2BB | 0.9700 |
C3A—C4A | 1.516 (2) | C3B—C4B | 1.521 (2) |
C3A—H3AA | 0.9700 | C3B—H3BA | 0.9700 |
C3A—H3AB | 0.9700 | C3B—H3BB | 0.9700 |
C4A—C5A | 1.511 (2) | C4B—C5B | 1.505 (2) |
C4A—H4AA | 0.9700 | C4B—H4BA | 0.9700 |
C4A—H4AB | 0.9700 | C4B—H4BB | 0.9700 |
N1A—C10A | 1.333 (2) | N1B—C10B | 1.338 (2) |
N1A—C6A | 1.342 (2) | N1B—C6B | 1.345 (2) |
N1A—H1AA | 0.8600 | N1B—H1BA | 0.8600 |
N2A—C8A | 1.323 (2) | N2B—C8B | 1.320 (2) |
N2A—H2AC | 0.8600 | N2B—H2BC | 0.8600 |
N2A—H2AD | 0.8600 | N2B—H2BD | 0.8600 |
C6A—C7A | 1.357 (3) | C6B—C7B | 1.368 (3) |
C6A—H6AA | 0.9300 | C6B—H6BA | 0.9300 |
C7A—C8A | 1.422 (2) | C7B—C8B | 1.403 (2) |
C7A—H7AA | 0.9300 | C7B—H7BA | 0.9300 |
C8A—C9A | 1.407 (2) | C8B—C9B | 1.415 (2) |
C9A—C10A | 1.370 (3) | C9B—C10B | 1.357 (3) |
C9A—H9AA | 0.9300 | C9B—H9BA | 0.9300 |
C10A—H10A | 0.9300 | C10B—H10B | 0.9300 |
C1A—O1A—H1O1 | 120.0 | C5B—O3B—H1O3 | 117.8 |
O2A—C1A—O1A | 120.78 (15) | O2B—C1B—O1B | 121.54 (15) |
O2A—C1A—C2A | 122.33 (15) | O2B—C1B—C2B | 121.05 (14) |
O1A—C1A—C2A | 116.89 (13) | O1B—C1B—C2B | 117.40 (13) |
C1A—C2A—C3A | 115.41 (12) | C1B—C2B—C3B | 114.68 (13) |
C1A—C2A—H2AA | 108.4 | C1B—C2B—H2BA | 108.6 |
C3A—C2A—H2AA | 108.4 | C3B—C2B—H2BA | 108.6 |
C1A—C2A—H2AB | 108.4 | C1B—C2B—H2BB | 108.6 |
C3A—C2A—H2AB | 108.4 | C3B—C2B—H2BB | 108.6 |
H2AA—C2A—H2AB | 107.5 | H2BA—C2B—H2BB | 107.6 |
C4A—C3A—C2A | 110.61 (12) | C2B—C3B—C4B | 110.07 (12) |
C4A—C3A—H3AA | 109.5 | C2B—C3B—H3BA | 109.6 |
C2A—C3A—H3AA | 109.5 | C4B—C3B—H3BA | 109.6 |
C4A—C3A—H3AB | 109.5 | C2B—C3B—H3BB | 109.6 |
C2A—C3A—H3AB | 109.5 | C4B—C3B—H3BB | 109.6 |
H3AA—C3A—H3AB | 108.1 | H3BA—C3B—H3BB | 108.2 |
C5A—C4A—C3A | 115.55 (13) | C5B—C4B—C3B | 115.13 (13) |
C5A—C4A—H4AA | 108.4 | C5B—C4B—H4BA | 108.5 |
C3A—C4A—H4AA | 108.4 | C3B—C4B—H4BA | 108.5 |
C5A—C4A—H4AB | 108.4 | C5B—C4B—H4BB | 108.5 |
C3A—C4A—H4AB | 108.4 | C3B—C4B—H4BB | 108.5 |
H4AA—C4A—H4AB | 107.5 | H4BA—C4B—H4BB | 107.5 |
O4A—C5A—O3A | 122.35 (15) | O4B—C5B—O3B | 120.63 (15) |
O4A—C5A—C4A | 119.61 (14) | O4B—C5B—C4B | 122.68 (15) |
O3A—C5A—C4A | 118.04 (13) | O3B—C5B—C4B | 116.69 (13) |
C10A—N1A—C6A | 120.06 (16) | C10B—N1B—C6B | 120.21 (16) |
C10A—N1A—H1AA | 120.0 | C10B—N1B—H1BA | 119.9 |
C6A—N1A—H1AA | 120.0 | C6B—N1B—H1BA | 119.9 |
C8A—N2A—H2AC | 120.0 | C8B—N2B—H2BC | 120.0 |
C8A—N2A—H2AD | 120.0 | C8B—N2B—H2BD | 120.0 |
H2AC—N2A—H2AD | 120.0 | H2BC—N2B—H2BD | 120.0 |
N1A—C6A—C7A | 122.55 (17) | N1B—C6B—C7B | 120.57 (17) |
N1A—C6A—H6AA | 118.7 | N1B—C6B—H6BA | 119.7 |
C7A—C6A—H6AA | 118.7 | C7B—C6B—H6BA | 119.7 |
C6A—C7A—C8A | 118.83 (17) | C6B—C7B—C8B | 120.38 (16) |
C6A—C7A—H7AA | 120.6 | C6B—C7B—H7BA | 119.8 |
C8A—C7A—H7AA | 120.6 | C8B—C7B—H7BA | 119.8 |
N2A—C8A—C9A | 120.67 (16) | N2B—C8B—C7B | 120.90 (15) |
N2A—C8A—C7A | 122.04 (16) | N2B—C8B—C9B | 121.69 (16) |
C9A—C8A—C7A | 117.29 (16) | C7B—C8B—C9B | 117.41 (16) |
C10A—C9A—C8A | 119.73 (16) | C10B—C9B—C8B | 118.75 (17) |
C10A—C9A—H9AA | 120.1 | C10B—C9B—H9BA | 120.6 |
C8A—C9A—H9AA | 120.1 | C8B—C9B—H9BA | 120.6 |
N1A—C10A—C9A | 121.52 (17) | N1B—C10B—C9B | 122.66 (17) |
N1A—C10A—H10A | 119.2 | N1B—C10B—H10B | 118.7 |
C9A—C10A—H10A | 119.2 | C9B—C10B—H10B | 118.7 |
O2A—C1A—C2A—C3A | 8.1 (3) | O2B—C1B—C2B—C3B | −4.8 (3) |
O1A—C1A—C2A—C3A | −172.34 (16) | O1B—C1B—C2B—C3B | 175.08 (17) |
C1A—C2A—C3A—C4A | 175.44 (15) | C1B—C2B—C3B—C4B | −175.99 (14) |
C2A—C3A—C4A—C5A | 174.42 (15) | C2B—C3B—C4B—C5B | −176.94 (15) |
C3A—C4A—C5A—O4A | 6.7 (3) | C3B—C4B—C5B—O4B | −5.5 (3) |
C3A—C4A—C5A—O3A | −173.38 (17) | C3B—C4B—C5B—O3B | 175.12 (16) |
C10A—N1A—C6A—C7A | −0.6 (3) | C10B—N1B—C6B—C7B | −0.9 (3) |
N1A—C6A—C7A—C8A | −0.3 (3) | N1B—C6B—C7B—C8B | 0.0 (3) |
C6A—C7A—C8A—N2A | −178.87 (18) | C6B—C7B—C8B—N2B | −178.91 (18) |
C6A—C7A—C8A—C9A | 1.1 (3) | C6B—C7B—C8B—C9B | 1.0 (3) |
N2A—C8A—C9A—C10A | 178.99 (18) | N2B—C8B—C9B—C10B | 178.79 (18) |
C7A—C8A—C9A—C10A | −1.0 (3) | C7B—C8B—C9B—C10B | −1.1 (3) |
C6A—N1A—C10A—C9A | 0.8 (3) | C6B—N1B—C10B—C9B | 0.8 (3) |
C8A—C9A—C10A—N1A | 0.1 (3) | C8B—C9B—C10B—N1B | 0.3 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1A—H1O1···O1Bi | 0.89 | 1.57 | 2.4591 (17) | 172 |
N1A—H1AA···O1Bii | 0.86 | 2.59 | 3.183 (2) | 127 |
N1A—H1AA···O2Bii | 0.86 | 1.87 | 2.729 (2) | 177 |
N2A—H2AC···O2Aiii | 0.86 | 2.18 | 2.9627 (19) | 151 |
N2A—H2AD···O4B | 0.86 | 2.10 | 2.948 (2) | 170 |
O3B—H1O3···O3Aiv | 0.92 | 1.56 | 2.4791 (17) | 176 |
C10A—H10A···O4Bv | 0.93 | 2.55 | 3.161 (2) | 124 |
C7A—H7AA···O3B | 0.93 | 2.47 | 3.370 (2) | 162 |
Symmetry codes: (i) x−1, y+1, z−1; (ii) x−1, y+1, z; (iii) x, −y+3/2, z+1/2; (iv) x, y, z+1; (v) −x+1, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C5H7N2+·C5H7O4− |
Mr | 226.23 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 9.6159 (2), 10.3065 (2), 22.6801 (5) |
β (°) | 102.143 (1) |
V (Å3) | 2197.45 (8) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.35 × 0.26 × 0.21 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.963, 0.978 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7931, 7931, 5556 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.758 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.053, 0.154, 1.04 |
No. of reflections | 7931 |
No. of parameters | 290 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.37, −0.20 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O1A—H1O1···O1Bi | 0.8900 | 1.5700 | 2.4591 (17) | 172.00 |
N1A—H1AA···O1Bii | 0.8600 | 2.5900 | 3.183 (2) | 127.00 |
N1A—H1AA···O2Bii | 0.8600 | 1.8700 | 2.729 (2) | 177.00 |
N2A—H2AC···O2Aiii | 0.8600 | 2.1800 | 2.9627 (19) | 151.00 |
N2A—H2AD···O4B | 0.8600 | 2.1000 | 2.948 (2) | 170.00 |
O3B—H1O3···O3Aiv | 0.9200 | 1.5600 | 2.4791 (17) | 176.00 |
C10A—H10A···O4Bv | 0.9300 | 2.5500 | 3.161 (2) | 124.00 |
C7A—H7AA···O3B | 0.9300 | 2.4700 | 3.370 (2) | 162.00 |
Symmetry codes: (i) x−1, y+1, z−1; (ii) x−1, y+1, z; (iii) x, −y+3/2, z+1/2; (iv) x, y, z+1; (v) −x+1, y+1/2, −z+3/2. |
Footnotes
‡Thomson Reuters ResearcherID: A-3561-2009.
Acknowledgements
HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.
References
Anderson, F. P., Gallagher, J. F., Kenny, P. T. M. & Lough, A. J. (2005). Acta Cryst. E61, o1350–o1353. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chao, M. & Schempp, E. (1977). Acta Cryst. B33, 1557–1564. CSD CrossRef CAS IUCr Journals Web of Science Google Scholar
Saraswathi, N. T., Manoj, N. & Vijayan, M. (2001). Acta Cryst. B57, 366–371. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Schwid, S. R., Petrie, M. D., McDermott, M. P., Tierney, D. S., Mason, D. H. & Goodman, A. D. (1997). Neurology, 48, 817–821. CrossRef CAS PubMed Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
4-Aminopyridine (fampridine) is used in the treatment of neurological ailments, such as multiple sclerosis (MS), with tests showing that fampridine improves motor function in MS patients (Schwid et al., 1997). The room temperature crystal structure of 4-aminopyridine was reported many years ago (Chao & Schempp, 1977); a redetermination at low temperature has been reported more recently (Anderson et al., 2005). Aliphatic dicarboxylic acids, HOOC(CH2)nCOOH, exhibit interesting complexing properties. This is due to the flexibility of the ligand which may be completely or only partially deprotonated. Glutaric acid (1,3-propanedicarboxylic acid) is a white crystalline solid which is very soluble in water. The compound is a useful building block for polymers, an intermediate in chemical synthesis and it is used in the manufacture of an antiretroviral drug. The compound is also used in solder flux. The present study has been carried out to study the hydrogen bonding patterns present in the crystal structure of 4-aminopyridinium 4-carboxybutanoate.
The asymmetric unit of the title compound consists of two crystallographically independent 4-aminopyridinium cations (A and B) and 4-carboxybutanoate (hydrogen glutarate) anions (A and B) (Fig. 1). Each 4-aminopyridinium cation is planar, with a maximum deviation of 0.005 (2) Å for atom C7A in cation A and 0.005 (2) Å for atom C9B in cation B. In the cations, protonation at atoms N1A and N1B lead to a slight increase in the C6A—N1A—C10A [120.06 (16)°] and C6B—N1B—C10B [120.21 (16)°] angles compared to those observed in the unprotonated structure of 4-aminopyridine (Anderson et al., 2005). The conformations of the 4-carboxybutanoate anions can be described by the two torsion angles C1A—C2A—C3A—C4A of 175.44 (15)° and C2A—C3A—C4A—C5A of 174.42 (15)° in anion A; C1B—C2B—C3B—C4B of -175.99 (14)° and C2B—C3B—C4B—C5B of -176.94 (15)° in anion B. These torsion angles indicate that both anions adopt fully extended conformations (Saraswathi et al., 2001).
In the crystal structure (Fig. 2), the cations and anions are linked via O1A—H1O1···O1B, N1A—H1AA···O1B, N1A—H1AA···O2B, N2A—H2AC···O2A, N2A—H2AD···O4B, O3B—H1O3···O3A, C10A—H10A···O4B and C7A—H7AA···03B intermolecular hydrogen bonds (Table 1), forming a two-dimensional network parallel to the bc-plane.
The crystal structure is a merohedral twin, with BASF = 0.3214 (15).