Kynurenic acid (KYN; systematic name: 4-hydroxyquinoline-2-carboxylic acid, C10H7NO3) displays a therapeutic effect in the treatment of some neurological diseases and is used as a broad-spectrum neuroprotective agent. However, it is understudied with respect to its solid-state chemistry and only one crystal form (α-KYN·H2O) has been reported up to now. Therefore, an attempt to synthesize alternative solid-state forms of KYN was undertaken and six new species were obtained: five solvates and one salt. One of them is a new polymorph, β-KYN·H2O, of the already known KYN monohydrate. All crystal species were further studied by single-crystal and powder X-ray diffraction, thermal and spectroscopic methods. In addition to the above methods, differential scanning calorimetry (DSC), in-situ variable-temperature powder X-ray diffraction and Raman microscopy were applied to characterize the phase behaviour of the new forms. All the compounds display a zwitterionic form of KYN and two different enol–keto tautomers are observed depending on the crystallization solvent used.
Supporting information
CCDC references: 1913007; 1916475
Data collection: CrysAlis CCD 1.171.38.41 (Rigaku Oxford Diffraction, 2015) for ortho_a; CrysAlis CCD (Rigaku OD, 2015) for kyn_100. Cell refinement: CrysAlis RED 1.171.38.41 (Rigaku Oxford Diffraction, 2015) for ortho_a; CrysAlis RED (Rigaku OD, 2015) for kyn_100. Data reduction: CrysAlis RED 1.171.38.41 (Rigaku Oxford Diffraction, 2015) for ortho_a; CrysAlis RED (Rigaku OD, 2015) for kyn_100. Program(s) used to solve structure: SHELXT (Sheldrick, 2014) for ortho_a; SHELXT (Sheldrick, 2015a) for kyn_100. Program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2014) for ortho_a; SHELXL2014 (Sheldrick, 2015b) for kyn_100. Molecular graphics: Brandenburg & Putz (2006). Diamond 3.0. Crystal and Molecular Structure Visualisation, University of Bonn, Germany for ortho_a; DIAMOND (Brandenburg, 2005) for kyn_100. Software used to prepare material for publication: SHELXL2014/7 (Sheldrick, 2014) for ortho_a; SHELXL2014 (Sheldrick, 2015b) for kyn_100.
Crystal data top
C10H7NO3·H2O | Dx = 1.553 Mg m−3 |
Mr = 207.18 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pccn | Cell parameters from 1562 reflections |
a = 13.9295 (7) Å | θ = 2.3–27.0° |
b = 17.8065 (9) Å | µ = 0.12 mm−1 |
c = 7.1429 (4) Å | T = 100 K |
V = 1771.69 (16) Å3 | Parallelepiped, colourless |
Z = 8 | 0.28 × 0.26 × 0.23 mm |
F(000) = 864 | |
Data collection top
KUMA KM-4 with CCD detector diffractometer | 2447 independent reflections |
Radiation source: fine-focus sealed X-ray tube | 2260 reflections with I > 2σ(I) |
Detector resolution: 10.6249 pixels mm-1 | Rint = 0.020 |
ω–scan | θmax = 30.5°, θmin = 2.3° |
Absorption correction: multi-scan CrysAlisPro 1.171.38.43 (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm. | h = −19→19 |
Tmin = 0.984, Tmax = 1.000 | k = −23→23 |
32133 measured reflections | l = −10→10 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.030 | Only H-atom coordinates refined |
wR(F2) = 0.080 | w = 1/[σ2(Fo2) + (0.0444P)2 + 0.7162P] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max < 0.001 |
2447 reflections | Δρmax = 0.38 e Å−3 |
164 parameters | Δρmin = −0.19 e Å−3 |
0 restraints | Extinction correction: SHELXL-2014/7 (Sheldrick 2014, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.017 (2) |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
N1 | 0.60814 (5) | 0.25460 (4) | 0.26030 (10) | 0.00951 (15) | |
H1N | 0.6586 (9) | 0.2352 (6) | 0.2109 (16) | 0.011* | |
C2 | 0.60012 (5) | 0.32951 (4) | 0.26966 (11) | 0.00928 (16) | |
C3 | 0.51748 (5) | 0.36310 (4) | 0.33814 (11) | 0.01005 (16) | |
H3 | 0.5129 (8) | 0.4163 (6) | 0.3451 (16) | 0.012* | |
C4 | 0.44019 (5) | 0.31826 (4) | 0.39471 (11) | 0.01007 (16) | |
C5 | 0.44945 (5) | 0.23815 (4) | 0.38734 (11) | 0.00983 (16) | |
C6 | 0.37499 (6) | 0.18888 (5) | 0.44390 (12) | 0.01269 (17) | |
H6 | 0.3171 (9) | 0.2091 (6) | 0.4936 (17) | 0.015* | |
C7 | 0.38693 (6) | 0.11256 (5) | 0.42899 (12) | 0.01416 (17) | |
H7 | 0.3375 (9) | 0.0784 (6) | 0.4657 (17) | 0.017* | |
C8 | 0.47348 (6) | 0.08246 (4) | 0.35792 (12) | 0.01295 (17) | |
H8 | 0.4794 (8) | 0.0285 (7) | 0.3493 (16) | 0.016* | |
C9 | 0.54791 (6) | 0.12872 (4) | 0.30432 (11) | 0.01149 (16) | |
H9 | 0.6068 (8) | 0.1103 (7) | 0.2529 (16) | 0.014* | |
C10 | 0.53604 (5) | 0.20721 (4) | 0.31834 (11) | 0.00954 (16) | |
C1 | 0.68546 (5) | 0.37417 (4) | 0.19377 (11) | 0.00994 (16) | |
O1 | 0.68350 (4) | 0.44422 (3) | 0.21907 (8) | 0.01315 (14) | |
O2 | 0.74812 (4) | 0.33700 (3) | 0.11000 (9) | 0.01250 (14) | |
O3 | 0.35788 (4) | 0.34571 (3) | 0.45420 (9) | 0.01335 (14) | |
H3O | 0.3536 (9) | 0.3973 (7) | 0.4459 (17) | 0.020* | |
O4 | 0.34159 (4) | 0.48782 (3) | 0.44271 (10) | 0.01426 (14) | |
H4A | 0.3408 (9) | 0.5088 (7) | 0.5521 (19) | 0.021* | |
H4B | 0.2921 (9) | 0.5062 (7) | 0.3845 (18) | 0.021* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
N1 | 0.0083 (3) | 0.0083 (3) | 0.0120 (3) | 0.0006 (2) | 0.0004 (2) | 0.0001 (2) |
C2 | 0.0087 (3) | 0.0089 (3) | 0.0102 (3) | −0.0005 (3) | −0.0010 (3) | 0.0004 (3) |
C3 | 0.0098 (3) | 0.0078 (3) | 0.0125 (3) | 0.0002 (3) | −0.0002 (3) | 0.0001 (3) |
C4 | 0.0088 (3) | 0.0110 (4) | 0.0105 (3) | 0.0006 (3) | −0.0005 (3) | −0.0004 (3) |
C5 | 0.0091 (3) | 0.0096 (4) | 0.0109 (3) | −0.0004 (2) | −0.0014 (3) | −0.0001 (3) |
C6 | 0.0097 (3) | 0.0126 (4) | 0.0157 (4) | −0.0011 (3) | −0.0001 (3) | 0.0004 (3) |
C7 | 0.0128 (4) | 0.0124 (4) | 0.0173 (4) | −0.0040 (3) | −0.0008 (3) | 0.0012 (3) |
C8 | 0.0160 (4) | 0.0079 (4) | 0.0150 (4) | −0.0009 (3) | −0.0020 (3) | −0.0005 (3) |
C9 | 0.0125 (3) | 0.0095 (4) | 0.0125 (3) | 0.0008 (3) | −0.0009 (3) | −0.0006 (3) |
C10 | 0.0095 (3) | 0.0093 (4) | 0.0098 (3) | −0.0008 (3) | −0.0012 (3) | 0.0003 (3) |
C1 | 0.0085 (3) | 0.0102 (4) | 0.0111 (3) | −0.0002 (2) | −0.0011 (3) | 0.0021 (3) |
O1 | 0.0136 (3) | 0.0081 (3) | 0.0178 (3) | −0.0009 (2) | 0.0020 (2) | 0.0004 (2) |
O2 | 0.0100 (3) | 0.0113 (3) | 0.0163 (3) | 0.0018 (2) | 0.0021 (2) | 0.0016 (2) |
O3 | 0.0088 (3) | 0.0100 (3) | 0.0213 (3) | 0.00129 (19) | 0.0032 (2) | −0.0005 (2) |
O4 | 0.0138 (3) | 0.0102 (3) | 0.0188 (3) | 0.0023 (2) | −0.0013 (2) | −0.0011 (2) |
Geometric parameters (Å, º) top
N1—C2 | 1.3402 (10) | C6—H6 | 0.953 (12) |
N1—C10 | 1.3758 (10) | C7—C8 | 1.4137 (12) |
N1—H1N | 0.860 (12) | C7—H7 | 0.956 (12) |
C2—C3 | 1.3865 (10) | C8—C9 | 1.3784 (11) |
C2—C1 | 1.5295 (10) | C8—H8 | 0.966 (12) |
C3—C4 | 1.4000 (10) | C9—C10 | 1.4108 (11) |
C3—H3 | 0.950 (11) | C9—H9 | 0.957 (12) |
C4—O3 | 1.3169 (9) | C1—O2 | 1.2481 (10) |
C4—C5 | 1.4333 (10) | C1—O1 | 1.2607 (10) |
C5—C10 | 1.4146 (10) | O3—H3O | 0.922 (13) |
C5—C6 | 1.4172 (11) | O4—H4A | 0.866 (14) |
C6—C7 | 1.3732 (11) | O4—H4B | 0.869 (13) |
| | | |
C2—N1—C10 | 122.32 (7) | C6—C7—C8 | 120.41 (7) |
C2—N1—H1N | 119.3 (7) | C6—C7—H7 | 121.5 (7) |
C10—N1—H1N | 118.3 (7) | C8—C7—H7 | 118.1 (7) |
N1—C2—C3 | 121.08 (7) | C9—C8—C7 | 120.97 (7) |
N1—C2—C1 | 115.78 (7) | C9—C8—H8 | 120.8 (7) |
C3—C2—C1 | 123.10 (7) | C7—C8—H8 | 118.2 (7) |
C2—C3—C4 | 119.62 (7) | C8—C9—C10 | 118.95 (7) |
C2—C3—H3 | 120.3 (7) | C8—C9—H9 | 123.1 (7) |
C4—C3—H3 | 120.1 (7) | C10—C9—H9 | 117.9 (7) |
O3—C4—C3 | 123.43 (7) | N1—C10—C9 | 120.04 (7) |
O3—C4—C5 | 117.36 (7) | N1—C10—C5 | 119.24 (7) |
C3—C4—C5 | 119.21 (7) | C9—C10—C5 | 120.70 (7) |
C10—C5—C6 | 118.83 (7) | O2—C1—O1 | 127.49 (7) |
C10—C5—C4 | 118.50 (7) | O2—C1—C2 | 115.96 (7) |
C6—C5—C4 | 122.67 (7) | O1—C1—C2 | 116.53 (7) |
C7—C6—C5 | 120.12 (7) | C4—O3—H3O | 113.9 (8) |
C7—C6—H6 | 120.4 (7) | H4A—O4—H4B | 105.0 (11) |
C5—C6—H6 | 119.5 (7) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O2i | 0.860 (12) | 1.964 (12) | 2.7968 (9) | 162.7 (11) |
O3—H3O···O4 | 0.922 (13) | 1.621 (13) | 2.5420 (8) | 176.3 (12) |
O4—H4A···O1ii | 0.866 (14) | 1.867 (14) | 2.7245 (9) | 170.1 (12) |
O4—H4B···O1iii | 0.869 (13) | 1.901 (13) | 2.7657 (8) | 172.8 (12) |
Symmetry codes: (i) −x+3/2, −y+1/2, z; (ii) −x+1, −y+1, −z+1; (iii) x−1/2, −y+1, −z+1/2. |
4-Hydroxyquinoline-2-carboxylic acid dimethyl sulfoxide monosolvate (kyn_100)
top
Crystal data top
C10H7NO3·C2H6OS | Dx = 1.449 Mg m−3 |
Mr = 267.29 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 4335 reflections |
a = 4.9552 (3) Å | θ = 4.0–28.7° |
b = 10.8444 (6) Å | µ = 0.27 mm−1 |
c = 22.7982 (11) Å | T = 100 K |
V = 1225.09 (12) Å3 | Parallelepiped, colourless |
Z = 4 | 0.41 × 0.21 × 0.12 mm |
F(000) = 560 | |
Data collection top
Kuma KM-4 with CCD detector diffractometer | 3044 independent reflections |
Radiation source: fine-focus sealed X-ray tube | 2756 reflections with I > 2σ(I) |
Detector resolution: 10.6249 pixels mm-1 | Rint = 0.043 |
ω–scan | θmax = 29.5°, θmin = 2.6° |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | h = −6→6 |
Tmin = 0.923, Tmax = 1.000 | k = −14→14 |
14513 measured reflections | l = −30→30 |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.036 | Only H-atom coordinates refined |
wR(F2) = 0.085 | w = 1/[σ2(Fo2) + (0.0461P)2 + 0.2943P] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max = 0.001 |
3044 reflections | Δρmax = 0.28 e Å−3 |
202 parameters | Δρmin = −0.25 e Å−3 |
0 restraints | Absolute structure: Flack x determined using 999 quotients [(I+)-(I-)]/[(I+)+(I-)]
(Parsons et al., 2013) |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.11 (4) |
Special details top
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. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
N1 | 0.4240 (4) | 0.57092 (18) | 0.64364 (8) | 0.0134 (4) | |
H1N | 0.400 (6) | 0.497 (3) | 0.6280 (11) | 0.016* | |
C1 | 0.2551 (4) | 0.6078 (2) | 0.68693 (9) | 0.0133 (5) | |
C2 | 0.2626 (4) | 0.7243 (2) | 0.70933 (10) | 0.0142 (5) | |
H2 | 0.136 (6) | 0.745 (2) | 0.7379 (11) | 0.017* | |
C3 | 0.4488 (5) | 0.8131 (2) | 0.68733 (10) | 0.0143 (4) | |
C4 | 0.6293 (4) | 0.7717 (2) | 0.64121 (9) | 0.0128 (4) | |
C5 | 0.6112 (4) | 0.6500 (2) | 0.62013 (10) | 0.0129 (5) | |
C6 | 0.8211 (5) | 0.8519 (2) | 0.61598 (10) | 0.0152 (4) | |
H6 | 0.833 (6) | 0.931 (3) | 0.6314 (11) | 0.018* | |
C7 | 0.9875 (5) | 0.8112 (2) | 0.57177 (10) | 0.0174 (5) | |
H7 | 1.122 (6) | 0.867 (2) | 0.5541 (11) | 0.021* | |
C8 | 0.9707 (5) | 0.6890 (2) | 0.55168 (10) | 0.0169 (5) | |
H8 | 1.090 (6) | 0.662 (3) | 0.5208 (12) | 0.020* | |
C9 | 0.7862 (5) | 0.6084 (2) | 0.57544 (9) | 0.0157 (5) | |
H9 | 0.776 (6) | 0.521 (3) | 0.5630 (12) | 0.019* | |
C10 | 0.0594 (5) | 0.5112 (2) | 0.70766 (10) | 0.0147 (5) | |
O1 | 0.0523 (3) | 0.40961 (15) | 0.68567 (7) | 0.0198 (4) | |
O2 | −0.0967 (3) | 0.55173 (16) | 0.74977 (7) | 0.0189 (4) | |
H2O | −0.213 (7) | 0.492 (3) | 0.7623 (13) | 0.028* | |
O3 | 0.4615 (3) | 0.92330 (15) | 0.70606 (8) | 0.0192 (4) | |
S1 | 0.31948 (12) | 0.24150 (5) | 0.59155 (3) | 0.01884 (15) | |
O4 | 0.4115 (4) | 0.36511 (15) | 0.56837 (7) | 0.0225 (4) | |
C11 | 0.5227 (6) | 0.2125 (3) | 0.65437 (12) | 0.0232 (5) | |
H11A | 0.706 (7) | 0.226 (3) | 0.6453 (14) | 0.035* | |
H11B | 0.491 (7) | 0.128 (3) | 0.6659 (13) | 0.035* | |
H11C | 0.465 (6) | 0.266 (3) | 0.6838 (13) | 0.035* | |
C12 | 0.4662 (8) | 0.1296 (3) | 0.54349 (13) | 0.0317 (6) | |
H12A | 0.374 (7) | 0.140 (3) | 0.5046 (15) | 0.048* | |
H12B | 0.435 (8) | 0.049 (3) | 0.5597 (15) | 0.048* | |
H12C | 0.657 (8) | 0.144 (3) | 0.5412 (15) | 0.048* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
N1 | 0.0127 (9) | 0.0113 (9) | 0.0161 (9) | −0.0004 (7) | 0.0006 (8) | −0.0021 (8) |
C1 | 0.0090 (10) | 0.0160 (11) | 0.0147 (10) | 0.0004 (8) | −0.0022 (8) | 0.0025 (9) |
C2 | 0.0114 (10) | 0.0153 (11) | 0.0159 (10) | 0.0009 (8) | −0.0004 (8) | 0.0019 (9) |
C3 | 0.0116 (10) | 0.0120 (11) | 0.0192 (11) | 0.0022 (9) | −0.0018 (9) | −0.0010 (9) |
C4 | 0.0085 (9) | 0.0157 (11) | 0.0142 (10) | 0.0014 (8) | −0.0009 (8) | 0.0013 (8) |
C5 | 0.0104 (10) | 0.0139 (11) | 0.0143 (10) | 0.0010 (8) | −0.0011 (8) | 0.0027 (8) |
C6 | 0.0123 (10) | 0.0150 (11) | 0.0184 (11) | 0.0016 (10) | −0.0022 (9) | 0.0005 (9) |
C7 | 0.0126 (10) | 0.0219 (13) | 0.0177 (11) | −0.0025 (9) | 0.0007 (9) | 0.0037 (9) |
C8 | 0.0137 (10) | 0.0236 (13) | 0.0136 (11) | 0.0012 (10) | 0.0033 (9) | −0.0012 (9) |
C9 | 0.0150 (10) | 0.0146 (11) | 0.0177 (11) | 0.0008 (9) | −0.0003 (9) | −0.0023 (8) |
C10 | 0.0129 (10) | 0.0150 (11) | 0.0162 (10) | 0.0002 (9) | 0.0011 (9) | 0.0015 (9) |
O1 | 0.0186 (8) | 0.0151 (9) | 0.0258 (8) | −0.0026 (7) | 0.0046 (7) | −0.0015 (7) |
O2 | 0.0164 (8) | 0.0142 (9) | 0.0262 (9) | −0.0015 (7) | 0.0082 (7) | −0.0002 (7) |
O3 | 0.0155 (8) | 0.0123 (8) | 0.0299 (9) | −0.0002 (7) | 0.0066 (7) | −0.0051 (7) |
S1 | 0.0185 (3) | 0.0155 (3) | 0.0225 (3) | −0.0032 (2) | −0.0012 (2) | −0.0010 (2) |
O4 | 0.0328 (10) | 0.0142 (9) | 0.0206 (8) | −0.0021 (7) | 0.0000 (8) | 0.0000 (7) |
C11 | 0.0239 (13) | 0.0219 (14) | 0.0238 (12) | −0.0004 (11) | 0.0002 (11) | 0.0023 (10) |
C12 | 0.0491 (19) | 0.0174 (14) | 0.0285 (14) | −0.0008 (13) | 0.0026 (14) | −0.0042 (11) |
Geometric parameters (Å, º) top
N1—C1 | 1.355 (3) | C8—C9 | 1.376 (3) |
N1—C5 | 1.372 (3) | C8—H8 | 0.96 (3) |
N1—H1N | 0.88 (3) | C9—H9 | 0.99 (3) |
C1—C2 | 1.363 (3) | C10—O1 | 1.210 (3) |
C1—C10 | 1.504 (3) | C10—O2 | 1.309 (3) |
C2—C3 | 1.425 (3) | O2—H2O | 0.92 (3) |
C2—H2 | 0.93 (3) | S1—O4 | 1.5112 (18) |
C3—O3 | 1.270 (3) | S1—C11 | 1.779 (3) |
C3—C4 | 1.452 (3) | S1—C12 | 1.789 (3) |
C4—C5 | 1.408 (3) | C11—H11A | 0.95 (3) |
C4—C6 | 1.411 (3) | C11—H11B | 0.97 (3) |
C5—C9 | 1.412 (3) | C11—H11C | 0.94 (3) |
C6—C7 | 1.375 (3) | C12—H12A | 1.00 (3) |
C6—H6 | 0.93 (3) | C12—H12B | 0.96 (4) |
C7—C8 | 1.404 (3) | C12—H12C | 0.96 (4) |
C7—H7 | 0.99 (3) | | |
| | | |
C1—N1—C5 | 121.2 (2) | C9—C8—H8 | 120.1 (17) |
C1—N1—H1N | 118.7 (18) | C7—C8—H8 | 119.2 (17) |
C5—N1—H1N | 119.8 (17) | C8—C9—C5 | 119.3 (2) |
N1—C1—C2 | 122.0 (2) | C8—C9—H9 | 121.9 (17) |
N1—C1—C10 | 114.9 (2) | C5—C9—H9 | 118.7 (17) |
C2—C1—C10 | 123.1 (2) | O1—C10—O2 | 126.3 (2) |
C1—C2—C3 | 120.8 (2) | O1—C10—C1 | 121.5 (2) |
C1—C2—H2 | 117.8 (17) | O2—C10—C1 | 112.15 (19) |
C3—C2—H2 | 121.3 (17) | C10—O2—H2O | 111.2 (19) |
O3—C3—C2 | 123.3 (2) | O4—S1—C11 | 105.51 (12) |
O3—C3—C4 | 120.2 (2) | O4—S1—C12 | 105.35 (14) |
C2—C3—C4 | 116.4 (2) | C11—S1—C12 | 98.24 (15) |
C5—C4—C6 | 118.8 (2) | S1—C11—H11A | 109.9 (19) |
C5—C4—C3 | 119.9 (2) | S1—C11—H11B | 107.1 (18) |
C6—C4—C3 | 121.3 (2) | H11A—C11—H11B | 111 (3) |
N1—C5—C4 | 119.7 (2) | S1—C11—H11C | 107.1 (19) |
N1—C5—C9 | 119.9 (2) | H11A—C11—H11C | 111 (3) |
C4—C5—C9 | 120.4 (2) | H11B—C11—H11C | 110 (3) |
C7—C6—C4 | 120.3 (2) | S1—C12—H12A | 106 (2) |
C7—C6—H6 | 122.4 (18) | S1—C12—H12B | 108 (2) |
C4—C6—H6 | 117.2 (17) | H12A—C12—H12B | 112 (3) |
C6—C7—C8 | 120.4 (2) | S1—C12—H12C | 109 (2) |
C6—C7—H7 | 120.3 (16) | H12A—C12—H12C | 112 (3) |
C8—C7—H7 | 119.2 (16) | H12B—C12—H12C | 109 (3) |
C9—C8—C7 | 120.7 (2) | | |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O4 | 0.88 (3) | 1.97 (3) | 2.816 (3) | 159 (2) |
O2—H2O···O3i | 0.92 (3) | 1.61 (3) | 2.494 (2) | 162 (3) |
Symmetry code: (i) −x, y−1/2, −z+3/2. |
The different solid-state species obtained under variable synthesis conditions topSolvent | Growth condition | Species as identified by PXRD |
Ethyl acetate + water | Slurry | species II (β-KYN.H2O) |
DMSO | Slow evaporation | species III (KYN.DMSO) |
Ethyl acetate | Slurry | species IV (KYN.EtAc) |
Ethanol 96% + NH4OH, pH = 8.5 | Slow evaporation | species V (NH4KYN) |
Ethanol + Chloroform + NH4OH, pH = 9.0 | Slow evaporation | species V (NH4KYN) |
Ethanol 96% | Slow evaporation | species VI (KYN) |
Ethanol 99.8% | Slow evaporation | species VI (KYN) |
Methanol | Slow evaporation | species VI (KYN) |
2-Propanol | Slow evaporation | species VI (KYN) |
Crystallographic Data and structure refinement parameters for KYN.H2O
(polymorphs α and β) and KYN.DMSO top | α-KYN.H2O (WISGOU) | β-KYN.H2O | KYN.DMSO |
Crystal data | | | |
Chemical formula | C10H7NO3·H2O | C10H7NO3·H2O | C10H7NO3·C2H6OS |
Mr | 207.19 | 207.18 | 267.29 |
Crystal system, space | Monoclinic, P21/n | Orthorhombic, Pccn | Orthorhombic, P212121 |
Temperature (K) | 296 | 100 | 100 |
a, b, c (Å) | 6.713 (3), 12.602 (4), 10.869 (6) | 13.9295 (7), 17.8065 (9), 7.1429 (4) | 4.9552 (3), 10.8444 (6), 22.7982 (11) |
β (°) | 94.10 (5) | 90 | 90 |
V (Å3) | 917.1 (7) | 1771.69 (16) | 1225.09 (12) |
Z | 4 | 8 | 4 |
Radiation type | Mo Kα | Mo Kα | Mo Kα |
µ (mm-1) | 0.110 | 0.12 | 0.27 |
Crystal size (mm) | 0.10 × 0.10 × 0.03 | 0.28 × 0.26 × 0.23 | 0.41 × 0.21 × 0.12 |
| | | |
Data Collection | | | |
Diffractometer | Rigaku AFC5R | KUMA KM-4 with CCD detector | KUMA KM-4 with CCD detector |
Absorption correction | | Multi-scan (CrysAlis PRO; Rigaku OD, 2015) | Multi-scan (CrysAlis PRO; Rigaku OD, 2015) |
Tmin, Tmax | - | 0.984, 1.000 | 0.923, 1.000 |
No. of measured, independent and
observed [I > 2σ(I)] reflections | 2385, 2207, 670 | 32133, 2447, 2260 | 14513, 3044, 2756 |
| | | |
Rint | 0.134 | 0.020 | 0.043 |
(sinθ/λ)max (Å-1) | 0.650 | 0.715 | 0.694 |
| | | |
Refinement | | | |
R[F2 > 2σ(F2)], wR(F2), S | 0.096, 0.079, - | 0.030, 0.080, 1.00 | 0.036, 0.085, 1.00 |
No. of reflections | 670 | 2447 | 3044 |
No. of parameters | 131 | 164 | 202 |
H-atom treatment | H-atom parameters refined isotropically | Only H-atom coordinates refined | Only H-atom coordinates refined |
Δρmax, Δρmin (e Å-3) | 0.43, -0.47 | 0.38, -0.19 | 0.28, -0.25 |
Absolute structure | - | - | Flack x determined using 999 quotients
[(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Absolute structure parameter | - | - | 0.11 (4) |
Computer programs for β-KYN.H2O and KYN.DMSO:
CrysAlis CCD (Rigaku OD, 2015),
CrysAlis RED (Rigaku OD, 2015),
SHELXT (Sheldrick, 2015a),
SHELXL2014 (Sheldrick, 2015b) and
DIAMOND (Brandenburg, 2005).
Computer programs α-KYN.H2O:
MSC/AFC Diffractometer Control Software (Molecular Structure
Corporation, 1988), TEXSAN (Molecular Structure Corporation,
1985),
SHELX86 (Sheldrick, 1990), DIRDIF (Beurskens,
1984) and
ORTEPII (Johnson, 1976). |
The geometry (Å, °) of the hydrogen bonds in β-KYN.H2O and KYN.DMSO topHydrogen bonds | D—H | H···A | D···A | D—H···A | Symmetry code |
α-KYN.H2O | | | | | |
N1—H1···O1 | 0.94 (12) | 2.16 (11) | 2.629 (12) | 110 | intramolecular |
N1—H1N···O3 | 0.94 (12) | 2.08 (12) | 2.924 (13) | 148 (9) | x, y, z |
O4—H4···O1 | 1.23 (11) | 1.30 (11) | 2.477 (11) | 158 (12) | -x+1/2, y+1/2, -z+3/2 |
β-KYN.H2O | | | | | |
N1—H1N···O2 | 0.859 (12) | 2.315 (11) | 2.6660 (9) | 104.7 (8) | intramolecular |
N1—H1N···O2 | 0.859 (12) | 1.965 (12) | 2.7968 (9) | 162.7 (11) | -x+3/2, -y+1/2, z |
O3—H3O···O4 | 0.923 (12) | 1.621 (12) | 2.5420 (8) | 176.4 (12) | x, y, z |
O4—H4A···O1 | 0.866 (13) | 1.867 (13) | 2.7245 (9) | 170.2 (12) | -x+1, -y+1, -z+1 |
O4—H4B···O1 | 0.869 (13) | 1.901 (13) | 2.7637 (8) | 170.8 (12) | x-1/2, -y+1, -z+1/2 |
C9—H9···O2 | 0.957 (11) | 2.545 (11) | 3.2205 (10) | 137.4 (10) | -x+3/2, -y+1/2, z |
KYN.DMSO | | | | | |
N1—H1N···O1 | 0.88 | 2.38 | 2.716 (3) | 103 | intramolecular |
N1—H1N···O4 | 0.88 | 1.99 | 2.816 (3) | 155 | x, y, z |
O2—H2O···O3 | 0.84 | 1.69 | 2.495 (3) | 160 | -x, y-1/2, -z+3/2 |
C9—H9···O4 | 0.95 | 2.52 | 3.231 (3) | 132 | x, y, z |
C11—H11B···O3 | 0.98 | 2.39 | 3.365 (3) | 174 | x, y-1, z |
C11—H11C···O1 | 0.98 | 2.57 | 3.242 (3) | 126 | x, y, z |