organic compounds
4-[2-(4-Chlorophenyl)hydrazinylidene]-3-methyl-5-oxo-4,5-dihydro-1H-pyrazole-1-carbothioamide
aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangothri 574 199, Karnataka, India
*Correspondence e-mail: hkfun@usm.my
In the title molecule, C11H10ClN5OS, an intramolecular N—H⋯O hydrogen forms an S(6) ring motif. The dihedral angle between the pyrazole ring and the benzene ring is 3.77 (8)°. In the crystal, molecules are linked by N—H⋯S and N—H⋯O hydrogen bonds into layers parallel to the bc plane.
Related literature
For the biological activity and pharmacological properties of pyrazole derivatives, see: Rai et al. (2008); Girisha et al. (2010); Isloor et al. (2009). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
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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/S1600536811038463/lh5337sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811038463/lh5337Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811038463/lh5337Isup3.cml
To a solution of ethyl-2-[(4-chlorophenyl)hydrazono]-3-oxobutanoate (0.01 mol) dissolved in glacial acetic acid (20 ml), a solution of thiosemicarbazide (0.02 mol) in glacial acetic acid (25 ml) was added and the mixture was refluxed for 4 h. It was cooled and allowed to stand overnight. The solid product that separated out was filtered and dried. It was then recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained from 1:2 mixtures of DMF and ethanol by slow evaporation.
N-bound H atoms was located from the difference map and refined freely, [N–H = 0.89 (2)–0.912 (18) Å]. The remaining H atoms were positioned geometrically [C–H = 0.93 or 0.96 Å] and refined using a riding model with Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating group model was applied to the methyl group.
Pyrazole derivatives are well established in the literatures as important biologically active
(Rai et al., 2008). These derivatives are the subject of many research studies due to their widespread pharmacological properties such as anti-inflammatory (Girisha et al., 2010), antipyretic, antimicrobial (Isloor et al., 2009), and antiviral activities. The widely prescribed anti-inflammatory pyrazole derivatives, celecoxib and deracoxib, are selective COX-2 inhibitors with reduced ulcerogenic side effects. The synthetic route followed for obtaining the title compound involves the diazotization of substituted anilines to give the followed by coupling with ethyl acetoacetate in the presence of sodium acetate to give corresponding oxobutanoate which on further reaction with thiosemicarbazide in acetic acid gave the required thioamides.The molecular structure is shown in Fig. 1. An intramolecular N4—H1N4···O1 hydrogen bond (Table 1) stabilizes the molecular structure and forms an S(6) ring motif (Bernstein et al., 1995). The dihedral angle between the 4,5-dihydro-1H-pyrazole (N1/N2/C1–C3) ring and the phenyl (C4–C9) ring is 3.77 (8)°. Bond lengths (Allen et al., 1987) and angles are within normal ranges.
The crystal packing is shown in Fig. 2. The molecules are linked by intermolecular N5—H1N5···S1i and N5—H2N5···O1ii hydrogen bonds (Table 1) into layers parallel to bc plane.
For the biological activity and pharmacological properties of pyrazole derivatives, see: Rai et al. (2008); Girisha et al. (2010); Isloor et al. (2009). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).
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).C11H10ClN5OS | F(000) = 1216 |
Mr = 295.75 | Dx = 1.506 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 9651 reflections |
a = 25.0899 (17) Å | θ = 2.9–29.9° |
b = 11.6075 (9) Å | µ = 0.45 mm−1 |
c = 9.0806 (6) Å | T = 296 K |
β = 99.516 (1)° | Block, orange |
V = 2608.2 (3) Å3 | 0.48 × 0.33 × 0.17 mm |
Z = 8 |
Bruker SMART APEXII DUO CCD area-detector diffractometer | 3827 independent reflections |
Radiation source: fine-focus sealed tube | 3125 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
φ and ω scans | θmax = 30.1°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −35→35 |
Tmin = 0.812, Tmax = 0.927 | k = −16→16 |
22139 measured reflections | l = −12→12 |
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)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.120 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0678P)2 + 1.0988P] where P = (Fo2 + 2Fc2)/3 |
3827 reflections | (Δ/σ)max = 0.003 |
185 parameters | Δρmax = 0.36 e Å−3 |
0 restraints | Δρmin = −0.49 e Å−3 |
C11H10ClN5OS | V = 2608.2 (3) Å3 |
Mr = 295.75 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 25.0899 (17) Å | µ = 0.45 mm−1 |
b = 11.6075 (9) Å | T = 296 K |
c = 9.0806 (6) Å | 0.48 × 0.33 × 0.17 mm |
β = 99.516 (1)° |
Bruker SMART APEXII DUO CCD area-detector diffractometer | 3827 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 3125 reflections with I > 2σ(I) |
Tmin = 0.812, Tmax = 0.927 | Rint = 0.024 |
22139 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.120 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | Δρmax = 0.36 e Å−3 |
3827 reflections | Δρmin = −0.49 e Å−3 |
185 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 | ||
S1 | 0.247690 (16) | 0.67094 (3) | 0.16327 (4) | 0.04930 (13) | |
Cl1 | 0.47498 (2) | 1.36700 (4) | 0.93948 (6) | 0.07500 (18) | |
O1 | 0.29887 (5) | 0.85770 (9) | 0.39231 (11) | 0.0481 (3) | |
N1 | 0.30587 (5) | 0.65709 (9) | 0.43842 (11) | 0.0376 (2) | |
N2 | 0.33273 (5) | 0.58737 (10) | 0.55643 (12) | 0.0456 (3) | |
N3 | 0.37848 (5) | 0.86126 (10) | 0.67837 (13) | 0.0431 (3) | |
N4 | 0.36803 (5) | 0.96471 (10) | 0.62440 (13) | 0.0424 (3) | |
N5 | 0.26388 (6) | 0.49214 (11) | 0.34633 (13) | 0.0489 (3) | |
C1 | 0.35437 (5) | 0.77370 (11) | 0.60545 (14) | 0.0397 (3) | |
C2 | 0.31655 (5) | 0.77385 (11) | 0.46481 (13) | 0.0358 (2) | |
C3 | 0.36083 (7) | 0.65570 (12) | 0.65135 (16) | 0.0471 (3) | |
C4 | 0.39475 (5) | 1.05982 (11) | 0.69841 (14) | 0.0389 (3) | |
C5 | 0.43223 (6) | 1.04497 (13) | 0.82750 (17) | 0.0504 (3) | |
H5A | 0.4408 | 0.9714 | 0.8647 | 0.060* | |
C6 | 0.45677 (7) | 1.14060 (14) | 0.90042 (19) | 0.0557 (4) | |
H6A | 0.4818 | 1.1317 | 0.9875 | 0.067* | |
C7 | 0.44409 (6) | 1.24900 (13) | 0.84375 (17) | 0.0479 (3) | |
C8 | 0.40700 (6) | 1.26442 (13) | 0.71486 (17) | 0.0510 (3) | |
H8A | 0.3988 | 1.3380 | 0.6774 | 0.061* | |
C9 | 0.38221 (6) | 1.16883 (12) | 0.64217 (17) | 0.0473 (3) | |
H9A | 0.3571 | 1.1780 | 0.5554 | 0.057* | |
C10 | 0.27250 (5) | 0.60195 (11) | 0.32065 (13) | 0.0374 (3) | |
C11 | 0.39486 (10) | 0.61297 (16) | 0.7902 (2) | 0.0773 (6) | |
H11A | 0.3845 | 0.5356 | 0.8097 | 0.116* | |
H11B | 0.3899 | 0.6616 | 0.8724 | 0.116* | |
H11C | 0.4322 | 0.6141 | 0.7782 | 0.116* | |
H1N4 | 0.3454 (7) | 0.9766 (17) | 0.536 (2) | 0.052 (5)* | |
H1N5 | 0.2758 (8) | 0.4615 (18) | 0.435 (2) | 0.060 (5)* | |
H2N5 | 0.2431 (8) | 0.4515 (19) | 0.272 (2) | 0.064 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0633 (2) | 0.0481 (2) | 0.03108 (17) | 0.00100 (15) | −0.00811 (14) | 0.00135 (12) |
Cl1 | 0.0730 (3) | 0.0509 (2) | 0.0885 (4) | −0.00312 (19) | −0.0239 (2) | −0.0250 (2) |
O1 | 0.0625 (6) | 0.0356 (5) | 0.0409 (5) | 0.0050 (4) | −0.0071 (4) | 0.0029 (4) |
N1 | 0.0460 (6) | 0.0343 (5) | 0.0287 (5) | −0.0019 (4) | −0.0046 (4) | 0.0015 (4) |
N2 | 0.0584 (7) | 0.0352 (5) | 0.0371 (5) | −0.0016 (5) | −0.0104 (5) | 0.0047 (4) |
N3 | 0.0486 (6) | 0.0387 (5) | 0.0392 (5) | −0.0032 (5) | −0.0011 (5) | −0.0034 (4) |
N4 | 0.0485 (6) | 0.0366 (5) | 0.0384 (5) | −0.0032 (4) | −0.0034 (5) | −0.0035 (4) |
N5 | 0.0674 (8) | 0.0416 (6) | 0.0326 (5) | −0.0111 (6) | −0.0067 (5) | −0.0016 (5) |
C1 | 0.0455 (7) | 0.0359 (6) | 0.0343 (5) | −0.0020 (5) | −0.0035 (5) | −0.0011 (5) |
C2 | 0.0411 (6) | 0.0342 (6) | 0.0306 (5) | 0.0010 (5) | 0.0019 (4) | −0.0003 (4) |
C3 | 0.0566 (8) | 0.0391 (6) | 0.0389 (6) | −0.0021 (6) | −0.0118 (6) | 0.0031 (5) |
C4 | 0.0398 (6) | 0.0382 (6) | 0.0374 (6) | −0.0020 (5) | 0.0020 (5) | −0.0059 (5) |
C5 | 0.0521 (8) | 0.0413 (7) | 0.0515 (8) | 0.0038 (6) | −0.0099 (6) | −0.0034 (6) |
C6 | 0.0529 (8) | 0.0523 (8) | 0.0531 (8) | 0.0040 (7) | −0.0175 (7) | −0.0083 (7) |
C7 | 0.0438 (7) | 0.0429 (7) | 0.0529 (7) | −0.0011 (5) | −0.0037 (6) | −0.0127 (6) |
C8 | 0.0552 (8) | 0.0379 (7) | 0.0547 (8) | −0.0012 (6) | −0.0060 (6) | −0.0025 (6) |
C9 | 0.0518 (8) | 0.0412 (7) | 0.0431 (7) | −0.0022 (6) | −0.0087 (6) | −0.0011 (5) |
C10 | 0.0414 (6) | 0.0404 (6) | 0.0286 (5) | −0.0022 (5) | 0.0008 (4) | −0.0036 (4) |
C11 | 0.1033 (15) | 0.0516 (9) | 0.0583 (10) | −0.0039 (9) | −0.0415 (10) | 0.0100 (8) |
S1—C10 | 1.6664 (13) | C1—C2 | 1.4597 (17) |
Cl1—C7 | 1.7347 (14) | C3—C11 | 1.486 (2) |
O1—C2 | 1.2169 (16) | C4—C9 | 1.3813 (19) |
N1—C2 | 1.3945 (16) | C4—C5 | 1.3870 (19) |
N1—C10 | 1.3995 (15) | C5—C6 | 1.384 (2) |
N1—N2 | 1.4207 (15) | C5—H5A | 0.9300 |
N2—C3 | 1.2916 (18) | C6—C7 | 1.377 (2) |
N3—C1 | 1.3057 (17) | C6—H6A | 0.9300 |
N3—N4 | 1.3070 (16) | C7—C8 | 1.381 (2) |
N4—C4 | 1.4039 (16) | C8—C9 | 1.385 (2) |
N4—H1N4 | 0.912 (18) | C8—H8A | 0.9300 |
N5—C10 | 1.3200 (18) | C9—H9A | 0.9300 |
N5—H1N5 | 0.89 (2) | C11—H11A | 0.9600 |
N5—H2N5 | 0.91 (2) | C11—H11B | 0.9600 |
C1—C3 | 1.4331 (19) | C11—H11C | 0.9600 |
C2—N1—C10 | 130.50 (11) | C6—C5—H5A | 120.3 |
C2—N1—N2 | 111.74 (10) | C4—C5—H5A | 120.3 |
C10—N1—N2 | 117.72 (10) | C7—C6—C5 | 119.82 (14) |
C3—N2—N1 | 106.99 (11) | C7—C6—H6A | 120.1 |
C1—N3—N4 | 118.53 (12) | C5—C6—H6A | 120.1 |
N3—N4—C4 | 119.51 (11) | C6—C7—C8 | 121.12 (13) |
N3—N4—H1N4 | 121.7 (12) | C6—C7—Cl1 | 118.55 (11) |
C4—N4—H1N4 | 118.7 (12) | C8—C7—Cl1 | 120.33 (12) |
C10—N5—H1N5 | 120.4 (13) | C7—C8—C9 | 119.12 (14) |
C10—N5—H2N5 | 117.2 (13) | C7—C8—H8A | 120.4 |
H1N5—N5—H2N5 | 122.2 (19) | C9—C8—H8A | 120.4 |
N3—C1—C3 | 125.15 (12) | C4—C9—C8 | 120.05 (13) |
N3—C1—C2 | 128.49 (12) | C4—C9—H9A | 120.0 |
C3—C1—C2 | 106.35 (11) | C8—C9—H9A | 120.0 |
O1—C2—N1 | 129.93 (12) | N5—C10—N1 | 113.67 (11) |
O1—C2—C1 | 126.90 (12) | N5—C10—S1 | 124.52 (10) |
N1—C2—C1 | 103.17 (10) | N1—C10—S1 | 121.81 (10) |
N2—C3—C1 | 111.70 (12) | C3—C11—H11A | 109.5 |
N2—C3—C11 | 122.34 (14) | C3—C11—H11B | 109.5 |
C1—C3—C11 | 125.96 (13) | H11A—C11—H11B | 109.5 |
C9—C4—C5 | 120.50 (12) | C3—C11—H11C | 109.5 |
C9—C4—N4 | 118.80 (12) | H11A—C11—H11C | 109.5 |
C5—C4—N4 | 120.68 (12) | H11B—C11—H11C | 109.5 |
C6—C5—C4 | 119.38 (14) | ||
C2—N1—N2—C3 | −2.16 (17) | C2—C1—C3—C11 | −178.78 (18) |
C10—N1—N2—C3 | −179.95 (13) | N3—N4—C4—C9 | −178.31 (14) |
C1—N3—N4—C4 | −178.03 (13) | N3—N4—C4—C5 | 0.3 (2) |
N4—N3—C1—C3 | −178.84 (15) | C9—C4—C5—C6 | 0.5 (2) |
N4—N3—C1—C2 | 1.4 (2) | N4—C4—C5—C6 | −178.13 (14) |
C10—N1—C2—O1 | 1.0 (2) | C4—C5—C6—C7 | −0.5 (3) |
N2—N1—C2—O1 | −176.43 (14) | C5—C6—C7—C8 | 0.2 (3) |
C10—N1—C2—C1 | 179.99 (13) | C5—C6—C7—Cl1 | 179.16 (14) |
N2—N1—C2—C1 | 2.57 (15) | C6—C7—C8—C9 | 0.1 (3) |
N3—C1—C2—O1 | −3.2 (2) | Cl1—C7—C8—C9 | −178.82 (13) |
C3—C1—C2—O1 | 177.00 (14) | C5—C4—C9—C8 | −0.2 (2) |
N3—C1—C2—N1 | 177.80 (14) | N4—C4—C9—C8 | 178.48 (14) |
C3—C1—C2—N1 | −2.04 (15) | C7—C8—C9—C4 | −0.2 (3) |
N1—N2—C3—C1 | 0.72 (19) | C2—N1—C10—N5 | −167.44 (14) |
N1—N2—C3—C11 | −179.63 (18) | N2—N1—C10—N5 | 9.85 (18) |
N3—C1—C3—N2 | −178.98 (14) | C2—N1—C10—S1 | 13.6 (2) |
C2—C1—C3—N2 | 0.86 (19) | N2—N1—C10—S1 | −169.10 (10) |
N3—C1—C3—C11 | 1.4 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H1N4···O1 | 0.914 (18) | 2.114 (19) | 2.7903 (16) | 129.9 (16) |
N5—H1N5···S1i | 0.89 (2) | 2.76 (2) | 3.5239 (13) | 144.5 (16) |
N5—H2N5···O1ii | 0.91 (2) | 2.00 (2) | 2.9124 (15) | 177.0 (19) |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −x+1/2, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C11H10ClN5OS |
Mr | 295.75 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 296 |
a, b, c (Å) | 25.0899 (17), 11.6075 (9), 9.0806 (6) |
β (°) | 99.516 (1) |
V (Å3) | 2608.2 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.45 |
Crystal size (mm) | 0.48 × 0.33 × 0.17 |
Data collection | |
Diffractometer | Bruker SMART APEXII DUO CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.812, 0.927 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 22139, 3827, 3125 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.705 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.120, 1.04 |
No. of reflections | 3827 |
No. of parameters | 185 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.36, −0.49 |
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 |
N4—H1N4···O1 | 0.914 (18) | 2.114 (19) | 2.7903 (16) | 129.9 (16) |
N5—H1N5···S1i | 0.89 (2) | 2.76 (2) | 3.5239 (13) | 144.5 (16) |
N5—H2N5···O1ii | 0.91 (2) | 2.00 (2) | 2.9124 (15) | 177.0 (19) |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −x+1/2, y−1/2, −z+1/2. |
Footnotes
‡Thomson Reuters ResearcherID: A-3561-2009.
Acknowledgements
The authors thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). SA also thanks the Malaysian Government and USM for the Academic Staff Training Scheme (ASTS) award.
References
Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CSD CrossRef Web of Science Google Scholar
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Pyrazole derivatives are well established in the literatures as important biologically active heterocyclic compounds (Rai et al., 2008). These derivatives are the subject of many research studies due to their widespread pharmacological properties such as anti-inflammatory (Girisha et al., 2010), antipyretic, antimicrobial (Isloor et al., 2009), and antiviral activities. The widely prescribed anti-inflammatory pyrazole derivatives, celecoxib and deracoxib, are selective COX-2 inhibitors with reduced ulcerogenic side effects. The synthetic route followed for obtaining the title compound involves the diazotization of substituted anilines to give the diazonium salts followed by coupling with ethyl acetoacetate in the presence of sodium acetate to give corresponding oxobutanoate which on further reaction with thiosemicarbazide in acetic acid gave the required thioamides.
The molecular structure is shown in Fig. 1. An intramolecular N4—H1N4···O1 hydrogen bond (Table 1) stabilizes the molecular structure and forms an S(6) ring motif (Bernstein et al., 1995). The dihedral angle between the 4,5-dihydro-1H-pyrazole (N1/N2/C1–C3) ring and the phenyl (C4–C9) ring is 3.77 (8)°. Bond lengths (Allen et al., 1987) and angles are within normal ranges.
The crystal packing is shown in Fig. 2. The molecules are linked by intermolecular N5—H1N5···S1i and N5—H2N5···O1ii hydrogen bonds (Table 1) into layers parallel to bc plane.