Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807045588/cv2303sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807045588/cv2303Isup2.hkl |
CCDC reference: 609616
Metronidazole (96%) and HSe aqua-solution (50%) wee purchased from Nanjing Chemical Company, Nanjing, P. R. China. TLC was run on the silica gel coated aluminium sheets (silica gel 60 GF254, E. Merk, Germany) and visualized in UV light (254 nm).
Metronidazole was dissolved in anhydrous DMF and the solution was stirred at 100 °C for 15 min. Then HSe in anhydrous DMF (20 ml) was carefully added, the mixed solution was stirred at 100 °C for 4 h. The mixture was cooled to the room temperature, and the solvent was removed under reduced pressure. The residue was suspended in EtOH and filtered, the solvent was removed under reduced pressure, and the residue was chromatographed. Elution with EtOAc gave an oil, which was recrystallized from EtOAc/petroleum ether (3/1) to give the title compound. Mp: 88.5–89.5 °C; Yield: 73%; 1H NMR (DMSO-d6): 2.50 (s, 3H, –CH3-); 3.51 (t, J = 8.68 Hz, 2H, N—CH2-); 4.61 (t, J = 8.51 Hz, 2H, –CH2-); 8.05 (s, 1H).
H atoms attached to C atoms were refined in the riding model approximation, with C–H = 0.93 Å and Uiso(H) = 1.2Ueq(C). The H atom attached to Se atom was located from a difference Fourier map and refined with bond restraint Se–H = 0.97 (1) Å, and with Uiso(H) = 1.2Uiso(Se).
The title compound, (I) (Fig. 1), is a selenol substituent derivative of metronidazole, which is extensively used in the treatment of anaerobic infections and is under continuing investigation. Earlier, the crystal structures of chloro- and iodometronidazole were reported by Pi et al. (2005) and Yang et al. (2005), respectively.
In (I), the imidazole ring and nitro group make a dihedral angle of 6.6 (1)°, while the torsion angle N2—C2—C1—Se is 59.5 (8)°.
The crystal structures of chloro- and iodometronidazole were reported by Pi et al. (2005) and Yang et al. (2005), respectively.
Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).
Fig. 1. The molecular structure of (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme. |
C6H9N3O2Se | F(000) = 464 |
Mr = 234.12 | Dx = 1.836 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 12.079 (2) Å | Cell parameters from 1542 reflections |
b = 11.089 (2) Å | θ = 3.9–26.4° |
c = 6.3800 (13) Å | µ = 4.40 mm−1 |
β = 97.57 (3)° | T = 293 K |
V = 847.1 (3) Å3 | Prism, yellow |
Z = 4 | 0.36 × 0.32 × 0.25 mm |
Bruker APEX area-detector diffractometer | 1647 independent reflections |
Radiation source: fine-focus sealed tube | 960 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.046 |
φ and ω scans | θmax = 26.0°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −14→14 |
Tmin = 0.272, Tmax = 0.352 | k = −13→0 |
1804 measured reflections | l = 0→7 |
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)] = 0.065 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.178 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0611P)2 + 4.5156P] where P = (Fo2 + 2Fc2)/3 |
1647 reflections | (Δ/σ)max < 0.001 |
112 parameters | Δρmax = 0.48 e Å−3 |
1 restraint | Δρmin = −0.63 e Å−3 |
C6H9N3O2Se | V = 847.1 (3) Å3 |
Mr = 234.12 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.079 (2) Å | µ = 4.40 mm−1 |
b = 11.089 (2) Å | T = 293 K |
c = 6.3800 (13) Å | 0.36 × 0.32 × 0.25 mm |
β = 97.57 (3)° |
Bruker APEX area-detector diffractometer | 1647 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 960 reflections with I > 2σ(I) |
Tmin = 0.272, Tmax = 0.352 | Rint = 0.046 |
1804 measured reflections |
R[F2 > 2σ(F2)] = 0.065 | 1 restraint |
wR(F2) = 0.178 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.48 e Å−3 |
1647 reflections | Δρmin = −0.63 e Å−3 |
112 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Se | 0.27158 (9) | 0.08541 (10) | 1.19615 (16) | 0.0625 (4) | |
O1 | 0.0341 (5) | −0.1194 (5) | 0.6752 (10) | 0.0483 (15) | |
O2 | 0.1029 (5) | −0.2980 (6) | 0.6766 (10) | 0.0546 (17) | |
N1 | 0.4065 (6) | −0.1286 (7) | 0.7038 (10) | 0.0402 (17) | |
N2 | 0.2522 (5) | −0.0209 (5) | 0.7252 (8) | 0.0263 (14) | |
N3 | 0.1135 (6) | −0.1880 (7) | 0.6843 (9) | 0.0364 (16) | |
C1 | 0.1470 (6) | 0.0813 (8) | 0.9825 (13) | 0.0408 (19) | |
H1B | 0.1035 | 0.0093 | 0.9999 | 0.049* | |
H1C | 0.0999 | 0.1507 | 0.9979 | 0.049* | |
C2 | 0.1822 (6) | 0.0817 (7) | 0.7604 (12) | 0.0331 (17) | |
H2A | 0.1159 | 0.0805 | 0.6564 | 0.040* | |
H2B | 0.2225 | 0.1556 | 0.7407 | 0.040* | |
C3 | 0.4326 (7) | 0.0927 (8) | 0.7434 (14) | 0.051 (2) | |
H3A | 0.5097 | 0.0723 | 0.7408 | 0.076* | |
H3B | 0.4246 | 0.1328 | 0.8740 | 0.076* | |
H3C | 0.4079 | 0.1452 | 0.6270 | 0.076* | |
C4 | 0.3641 (6) | −0.0192 (8) | 0.7257 (11) | 0.0343 (19) | |
C5 | 0.3193 (7) | −0.2051 (8) | 0.6905 (12) | 0.040 (2) | |
H5A | 0.3237 | −0.2883 | 0.6758 | 0.048* | |
C6 | 0.2233 (6) | −0.1415 (7) | 0.7020 (11) | 0.0275 (16) | |
H1 | 0.3517 (14) | 0.079 (7) | 1.193 (12) | 0.072* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Se | 0.0718 (8) | 0.0693 (7) | 0.0437 (6) | 0.0085 (6) | −0.0024 (5) | −0.0086 (5) |
O1 | 0.029 (3) | 0.064 (4) | 0.050 (4) | −0.005 (3) | −0.002 (3) | −0.009 (3) |
O2 | 0.052 (4) | 0.043 (4) | 0.067 (4) | −0.014 (3) | 0.005 (3) | −0.012 (3) |
N1 | 0.031 (4) | 0.059 (5) | 0.032 (4) | 0.005 (3) | 0.007 (3) | −0.002 (3) |
N2 | 0.027 (4) | 0.037 (4) | 0.015 (3) | 0.001 (3) | 0.003 (2) | 0.002 (3) |
N3 | 0.040 (4) | 0.050 (5) | 0.020 (3) | −0.007 (4) | 0.004 (3) | −0.010 (3) |
C1 | 0.028 (4) | 0.046 (5) | 0.048 (5) | 0.010 (4) | 0.003 (4) | −0.004 (4) |
C2 | 0.025 (4) | 0.037 (4) | 0.036 (4) | 0.002 (4) | −0.002 (3) | 0.004 (4) |
C3 | 0.039 (5) | 0.062 (6) | 0.051 (5) | −0.014 (5) | 0.007 (4) | 0.004 (5) |
C4 | 0.036 (5) | 0.051 (5) | 0.016 (4) | −0.005 (4) | 0.007 (3) | 0.001 (3) |
C5 | 0.050 (5) | 0.041 (5) | 0.029 (4) | 0.013 (4) | 0.008 (4) | −0.006 (4) |
C6 | 0.030 (4) | 0.035 (4) | 0.016 (4) | −0.002 (4) | 0.001 (3) | −0.002 (3) |
Se—C1 | 1.893 (8) | C1—H1B | 0.9700 |
Se—H1 | 0.974 (10) | C1—H1C | 0.9700 |
O1—N3 | 1.220 (8) | C2—H2A | 0.9700 |
O2—N3 | 1.226 (8) | C2—H2B | 0.9700 |
N1—C4 | 1.331 (10) | C3—C4 | 1.489 (11) |
N1—C5 | 1.346 (10) | C3—H3A | 0.9600 |
N2—C4 | 1.350 (9) | C3—H3B | 0.9600 |
N2—C6 | 1.385 (9) | C3—H3C | 0.9600 |
N2—C2 | 1.454 (9) | C5—C6 | 1.367 (10) |
N3—C6 | 1.413 (10) | C5—H5A | 0.9300 |
C1—C2 | 1.532 (11) | ||
C1—Se—H1 | 133 (5) | C1—C2—H2B | 109.2 |
C4—N1—C5 | 105.8 (7) | H2A—C2—H2B | 107.9 |
C4—N2—C6 | 104.6 (6) | C4—C3—H3A | 109.5 |
C4—N2—C2 | 126.3 (6) | C4—C3—H3B | 109.5 |
C6—N2—C2 | 128.9 (6) | H3A—C3—H3B | 109.5 |
O1—N3—O2 | 122.7 (7) | C4—C3—H3C | 109.5 |
O1—N3—C6 | 120.0 (7) | H3A—C3—H3C | 109.5 |
O2—N3—C6 | 117.3 (7) | H3B—C3—H3C | 109.5 |
C2—C1—Se | 112.0 (5) | N1—C4—N2 | 112.7 (7) |
C2—C1—H1B | 109.2 | N1—C4—C3 | 123.4 (7) |
Se—C1—H1B | 109.2 | N2—C4—C3 | 123.9 (8) |
C2—C1—H1C | 109.2 | N1—C5—C6 | 109.5 (7) |
Se—C1—H1C | 109.2 | N1—C5—H5A | 125.3 |
H1B—C1—H1C | 107.9 | C6—C5—H5A | 125.3 |
N2—C2—C1 | 112.2 (6) | C5—C6—N2 | 107.4 (7) |
N2—C2—H2A | 109.2 | C5—C6—N3 | 126.9 (7) |
C1—C2—H2A | 109.2 | N2—C6—N3 | 125.6 (7) |
N2—C2—H2B | 109.2 | ||
C4—N2—C2—C1 | −103.4 (8) | N1—C5—C6—N2 | −0.5 (8) |
C6—N2—C2—C1 | 70.6 (9) | N1—C5—C6—N3 | 176.9 (7) |
Se—C1—C2—N2 | 59.5 (8) | C4—N2—C6—C5 | 0.1 (8) |
C5—N1—C4—N2 | −0.6 (8) | C2—N2—C6—C5 | −174.9 (6) |
C5—N1—C4—C3 | −179.2 (7) | C4—N2—C6—N3 | −177.3 (6) |
C6—N2—C4—N1 | 0.3 (8) | C2—N2—C6—N3 | 7.7 (11) |
C2—N2—C4—N1 | 175.5 (6) | O1—N3—C6—C5 | −172.2 (7) |
C6—N2—C4—C3 | 178.9 (7) | O2—N3—C6—C5 | 7.1 (11) |
C2—N2—C4—C3 | −5.9 (11) | O1—N3—C6—N2 | 4.7 (11) |
C4—N1—C5—C6 | 0.7 (8) | O2—N3—C6—N2 | −176.0 (7) |
Experimental details
Crystal data | |
Chemical formula | C6H9N3O2Se |
Mr | 234.12 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 12.079 (2), 11.089 (2), 6.3800 (13) |
β (°) | 97.57 (3) |
V (Å3) | 847.1 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 4.40 |
Crystal size (mm) | 0.36 × 0.32 × 0.25 |
Data collection | |
Diffractometer | Bruker APEX area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.272, 0.352 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1804, 1647, 960 |
Rint | 0.046 |
(sin θ/λ)max (Å−1) | 0.616 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.065, 0.178, 1.05 |
No. of reflections | 1647 |
No. of parameters | 112 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.48, −0.63 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 1997a), SHELXL97 (Sheldrick, 1997a), SHELXTL (Sheldrick, 1997b).
The title compound, (I) (Fig. 1), is a selenol substituent derivative of metronidazole, which is extensively used in the treatment of anaerobic infections and is under continuing investigation. Earlier, the crystal structures of chloro- and iodometronidazole were reported by Pi et al. (2005) and Yang et al. (2005), respectively.
In (I), the imidazole ring and nitro group make a dihedral angle of 6.6 (1)°, while the torsion angle N2—C2—C1—Se is 59.5 (8)°.