organic compounds
N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)carbamate
of ethylaDepartment of Chemistry, Institute of Natural Sciences, University of Gujrat, Gujrat 50700, Pakistan, and bDepartment of Physics, University of Sargodha, Sargodha, Punjab, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com
In the title compound, C14H17N3O3, the dihedral angle between the benzene ring and the five-membered dihydropyrazole ring is 52.26 (9)°. The ethyl ester group is approximately planar (r.m.s. deviation 0.0568 Å) and subtends an angle 67.73 (8)° to the pyrazole ring. In the crystal, molecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with an R22(10) ring motif. Weaker C—H⋯O contacts link these dimers into a three-dimensional network of molecules stacked along the a-axis direction. Offset π–π stacking interactions between the benzene rings [centroid-to-centroid distance = 3.8832 (12) Å] further stabilize the crystal packing.
Keywords: crystal structure; dihydropyrazole; ethyl ester; carbamate; hydrogen bonding; π–π stacking interactions.
CCDC reference: 1056157
2. Experimental
2.1. Crystal data
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2.3. Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/6 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON.
Supporting information
CCDC reference: 1056157
10.1107/S2056989015006106/sj5447sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015006106/sj5447Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015006106/sj5447Isup3.cml
4-aminoantipyrene (2 g, 9.84 mmole) was dissolved in 50 ml dimethyl formamide and anhydrous potassium carbonate (0.68 g, 4.92 mmole) was added with continuous stirring over 50 minutes. Ethyl chloroformate (1.3 ml) was added drop-wise with stirring over three minutes at 323 K. TLC monitoring showed the reaction to be complete in almost 4 h. The reaction mixture was then cooled to room temperature and transferred to crushed ice leading to the formation of a precipitate. This was separated by filtration and recrystallized from aqueous ethanol to yield (I) as light yellow plates.
Melting point: 477–479 K.
The H-atoms were positioned geometrically (N–H = 0.86, C–H = 0.93–0.97 Å) and refined as riding with Uiso(H) = 1.2Ueq(C, N).
The title compound (I), (Fig. 1) has been synthesized to examine its DNA binding potential and anti-microbial activity. The crystal structures of two closely related compounds, methyl (1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H- pyrazol-4-yl)carbamate and methyl (1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)methylcarbamate monohydrate have been reported previously (Li et al., 2013).
In (I), the C1—C6 benzene ring and dihydropyrazol-3-one system, O1/N1/N2/N3/C7—C9 are planar with r.m.s. deviations of 0.0037 and 0.0398 Å, respectively. The dihedral angle between the two systems is 53.64 (5)°. The ethyl ester group, C12/C13/C14/O2/O3, is also planar (r.m.s. deviation 0.0568 Å) and subtends an angle 67.73 (8)° to the pyrazole ring. In the π···π stacking interactions between the benzene rings with Cg2···Cg2i = 3.8832 (12) Å further stabilise the crystal packing (Cg2 is the centroid of the C1—C6 benzene ring; i = 2 - x, -y, 1 - z).
classical N3—H3A···O1 hydrogen bonds form inversion dimers (Table 1, Fig. 2) with R22(10) ring motifs. Weaker C10–H10A···O1 and C11–H11B···O2 contacts link these dimers into a three dimensional network of molecules stacked along the a axis direction. OffsetFor related structures see: Li et al. (2013).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/6 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).C14H17N3O3 | F(000) = 584 |
Mr = 275.30 | Dx = 1.290 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 8.2100 (4) Å | Cell parameters from 2368 reflections |
b = 11.4137 (6) Å | θ = 2.2–27.0° |
c = 15.1594 (8) Å | µ = 0.09 mm−1 |
β = 93.403 (3)° | T = 296 K |
V = 1418.03 (13) Å3 | Plate, light yellow |
Z = 4 | 0.38 × 0.34 × 0.20 mm |
Bruker Kappa APEXII CCD diffractometer | 3098 independent reflections |
Radiation source: fine-focus sealed tube | 2368 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
Detector resolution: 7.80 pixels mm-1 | θmax = 27.0°, θmin = 2.2° |
ω scans | h = −10→10 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −14→13 |
Tmin = 0.968, Tmax = 0.983 | l = −19→19 |
11712 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.043 | H-atom parameters constrained |
wR(F2) = 0.127 | w = 1/[σ2(Fo2) + (0.0592P)2 + 0.2848P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
3098 reflections | Δρmax = 0.19 e Å−3 |
185 parameters | Δρmin = −0.17 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.027 (3) |
C14H17N3O3 | V = 1418.03 (13) Å3 |
Mr = 275.30 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.2100 (4) Å | µ = 0.09 mm−1 |
b = 11.4137 (6) Å | T = 296 K |
c = 15.1594 (8) Å | 0.38 × 0.34 × 0.20 mm |
β = 93.403 (3)° |
Bruker Kappa APEXII CCD diffractometer | 3098 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 2368 reflections with I > 2σ(I) |
Tmin = 0.968, Tmax = 0.983 | Rint = 0.022 |
11712 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.127 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.19 e Å−3 |
3098 reflections | Δρmin = −0.17 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 | ||
O1 | 0.54493 (13) | 0.33953 (9) | 0.54004 (6) | 0.0503 (3) | |
O2 | 0.13321 (16) | 0.32771 (12) | 0.33957 (11) | 0.0819 (5) | |
O3 | 0.09391 (13) | 0.51504 (10) | 0.38192 (8) | 0.0617 (3) | |
N1 | 0.65770 (15) | 0.23072 (11) | 0.42996 (8) | 0.0458 (3) | |
N2 | 0.62265 (16) | 0.21412 (12) | 0.33892 (8) | 0.0510 (3) | |
N3 | 0.34531 (15) | 0.44615 (11) | 0.38501 (8) | 0.0480 (3) | |
H3A | 0.3728 | 0.5172 | 0.3977 | 0.058* | |
C1 | 0.72550 (18) | 0.13738 (13) | 0.48290 (10) | 0.0472 (4) | |
C2 | 0.8305 (2) | 0.16528 (17) | 0.55395 (11) | 0.0592 (4) | |
H2 | 0.8595 | 0.2428 | 0.5653 | 0.071* | |
C3 | 0.8922 (3) | 0.0764 (2) | 0.60812 (14) | 0.0791 (6) | |
H3 | 0.9628 | 0.0945 | 0.6565 | 0.095* | |
C4 | 0.8508 (3) | −0.0376 (2) | 0.59139 (18) | 0.0851 (7) | |
H4 | 0.8924 | −0.0967 | 0.6285 | 0.102* | |
C5 | 0.7481 (3) | −0.06516 (17) | 0.52008 (19) | 0.0841 (7) | |
H5 | 0.7216 | −0.1431 | 0.5085 | 0.101* | |
C6 | 0.6830 (2) | 0.02230 (15) | 0.46480 (14) | 0.0639 (5) | |
H6 | 0.6122 | 0.0038 | 0.4166 | 0.077* | |
C7 | 0.55368 (17) | 0.31534 (12) | 0.46080 (9) | 0.0406 (3) | |
C8 | 0.46691 (17) | 0.35940 (13) | 0.38352 (9) | 0.0430 (3) | |
C9 | 0.51590 (19) | 0.30017 (14) | 0.31216 (10) | 0.0487 (4) | |
C10 | 0.4694 (3) | 0.3221 (2) | 0.21696 (12) | 0.0755 (6) | |
H10A | 0.4626 | 0.2489 | 0.1858 | 0.113* | |
H10B | 0.5502 | 0.3709 | 0.1921 | 0.113* | |
H10C | 0.3654 | 0.3607 | 0.2117 | 0.113* | |
C11 | 0.7583 (2) | 0.17664 (16) | 0.28711 (12) | 0.0621 (5) | |
H11A | 0.7971 | 0.1016 | 0.3078 | 0.093* | |
H11B | 0.8452 | 0.2329 | 0.2937 | 0.093* | |
H11C | 0.7217 | 0.1709 | 0.2259 | 0.093* | |
C12 | 0.1866 (2) | 0.42031 (14) | 0.36699 (11) | 0.0528 (4) | |
C13 | −0.0815 (2) | 0.4956 (2) | 0.37242 (17) | 0.0818 (6) | |
H13A | −0.1108 | 0.4609 | 0.3152 | 0.098* | |
H13B | −0.1145 | 0.4424 | 0.4179 | 0.098* | |
C14 | −0.1628 (3) | 0.6069 (3) | 0.3803 (2) | 0.1237 (11) | |
H14A | −0.2786 | 0.5946 | 0.3798 | 0.186* | |
H14B | −0.1381 | 0.6563 | 0.3316 | 0.186* | |
H14C | −0.1259 | 0.6438 | 0.4348 | 0.186* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0619 (7) | 0.0475 (6) | 0.0425 (6) | 0.0067 (5) | 0.0099 (5) | −0.0044 (4) |
O2 | 0.0552 (7) | 0.0589 (9) | 0.1307 (13) | −0.0026 (6) | −0.0010 (8) | −0.0187 (8) |
O3 | 0.0453 (6) | 0.0558 (7) | 0.0849 (8) | 0.0115 (5) | 0.0113 (6) | 0.0010 (6) |
N1 | 0.0493 (7) | 0.0440 (7) | 0.0445 (7) | 0.0090 (6) | 0.0050 (5) | −0.0052 (5) |
N2 | 0.0517 (7) | 0.0558 (8) | 0.0458 (7) | 0.0106 (6) | 0.0067 (6) | −0.0112 (6) |
N3 | 0.0459 (7) | 0.0395 (7) | 0.0586 (8) | 0.0054 (5) | 0.0037 (6) | −0.0030 (5) |
C1 | 0.0421 (7) | 0.0439 (8) | 0.0568 (9) | 0.0089 (6) | 0.0134 (6) | 0.0019 (7) |
C2 | 0.0558 (9) | 0.0613 (11) | 0.0607 (10) | 0.0102 (8) | 0.0043 (8) | 0.0035 (8) |
C3 | 0.0691 (12) | 0.0960 (17) | 0.0724 (12) | 0.0247 (12) | 0.0054 (10) | 0.0187 (11) |
C4 | 0.0744 (14) | 0.0786 (15) | 0.1049 (17) | 0.0307 (12) | 0.0268 (13) | 0.0369 (13) |
C5 | 0.0725 (13) | 0.0453 (11) | 0.138 (2) | 0.0119 (10) | 0.0371 (14) | 0.0176 (12) |
C6 | 0.0542 (10) | 0.0488 (10) | 0.0901 (13) | 0.0032 (8) | 0.0156 (9) | −0.0036 (9) |
C7 | 0.0411 (7) | 0.0350 (7) | 0.0464 (8) | −0.0002 (6) | 0.0086 (6) | −0.0038 (6) |
C8 | 0.0423 (7) | 0.0396 (8) | 0.0476 (8) | 0.0030 (6) | 0.0067 (6) | −0.0019 (6) |
C9 | 0.0472 (8) | 0.0521 (9) | 0.0470 (8) | 0.0031 (7) | 0.0029 (6) | −0.0056 (6) |
C10 | 0.0805 (13) | 0.0979 (16) | 0.0474 (10) | 0.0178 (11) | −0.0019 (9) | −0.0074 (9) |
C11 | 0.0611 (10) | 0.0664 (11) | 0.0605 (10) | 0.0110 (9) | 0.0174 (8) | −0.0146 (8) |
C12 | 0.0487 (8) | 0.0479 (9) | 0.0622 (10) | 0.0056 (7) | 0.0067 (7) | 0.0021 (7) |
C13 | 0.0470 (10) | 0.0869 (15) | 0.1121 (17) | 0.0083 (10) | 0.0091 (10) | 0.0007 (13) |
C14 | 0.0581 (13) | 0.105 (2) | 0.211 (3) | 0.0252 (14) | 0.0337 (17) | 0.016 (2) |
O1—C7 | 1.2387 (17) | C4—H4 | 0.9300 |
O2—C12 | 1.208 (2) | C5—C6 | 1.390 (3) |
O3—C12 | 1.3489 (19) | C5—H5 | 0.9300 |
O3—C13 | 1.456 (2) | C6—H6 | 0.9300 |
N1—C7 | 1.3886 (18) | C7—C8 | 1.426 (2) |
N1—N2 | 1.4057 (17) | C8—C9 | 1.357 (2) |
N1—C1 | 1.4269 (19) | C9—C10 | 1.492 (2) |
N2—C9 | 1.362 (2) | C10—H10A | 0.9600 |
N2—C11 | 1.4645 (19) | C10—H10B | 0.9600 |
N3—C12 | 1.348 (2) | C10—H10C | 0.9600 |
N3—C8 | 1.4072 (18) | C11—H11A | 0.9600 |
N3—H3A | 0.8600 | C11—H11B | 0.9600 |
C1—C2 | 1.376 (2) | C11—H11C | 0.9600 |
C1—C6 | 1.383 (2) | C13—C14 | 1.443 (3) |
C2—C3 | 1.382 (3) | C13—H13A | 0.9700 |
C2—H2 | 0.9300 | C13—H13B | 0.9700 |
C3—C4 | 1.365 (3) | C14—H14A | 0.9600 |
C3—H3 | 0.9300 | C14—H14B | 0.9600 |
C4—C5 | 1.367 (4) | C14—H14C | 0.9600 |
C12—O3—C13 | 115.20 (15) | C9—C8—C7 | 108.79 (13) |
C7—N1—N2 | 109.28 (11) | N3—C8—C7 | 123.72 (12) |
C7—N1—C1 | 123.86 (12) | C8—C9—N2 | 109.74 (13) |
N2—N1—C1 | 120.12 (12) | C8—C9—C10 | 128.08 (15) |
C9—N2—N1 | 106.61 (11) | N2—C9—C10 | 122.17 (14) |
C9—N2—C11 | 123.19 (14) | C9—C10—H10A | 109.5 |
N1—N2—C11 | 116.61 (13) | C9—C10—H10B | 109.5 |
C12—N3—C8 | 121.39 (13) | H10A—C10—H10B | 109.5 |
C12—N3—H3A | 119.3 | C9—C10—H10C | 109.5 |
C8—N3—H3A | 119.3 | H10A—C10—H10C | 109.5 |
C2—C1—C6 | 120.94 (16) | H10B—C10—H10C | 109.5 |
C2—C1—N1 | 118.21 (15) | N2—C11—H11A | 109.5 |
C6—C1—N1 | 120.81 (15) | N2—C11—H11B | 109.5 |
C1—C2—C3 | 119.05 (19) | H11A—C11—H11B | 109.5 |
C1—C2—H2 | 120.5 | N2—C11—H11C | 109.5 |
C3—C2—H2 | 120.5 | H11A—C11—H11C | 109.5 |
C4—C3—C2 | 120.7 (2) | H11B—C11—H11C | 109.5 |
C4—C3—H3 | 119.6 | O2—C12—N3 | 125.98 (15) |
C2—C3—H3 | 119.6 | O2—C12—O3 | 124.21 (15) |
C3—C4—C5 | 120.1 (2) | N3—C12—O3 | 109.79 (14) |
C3—C4—H4 | 120.0 | C14—C13—O3 | 108.53 (19) |
C5—C4—H4 | 120.0 | C14—C13—H13A | 110.0 |
C4—C5—C6 | 120.6 (2) | O3—C13—H13A | 110.0 |
C4—C5—H5 | 119.7 | C14—C13—H13B | 110.0 |
C6—C5—H5 | 119.7 | O3—C13—H13B | 110.0 |
C1—C6—C5 | 118.6 (2) | H13A—C13—H13B | 108.4 |
C1—C6—H6 | 120.7 | C13—C14—H14A | 109.5 |
C5—C6—H6 | 120.7 | C13—C14—H14B | 109.5 |
O1—C7—N1 | 123.62 (13) | H14A—C14—H14B | 109.5 |
O1—C7—C8 | 131.54 (13) | C13—C14—H14C | 109.5 |
N1—C7—C8 | 104.82 (12) | H14A—C14—H14C | 109.5 |
C9—C8—N3 | 127.41 (14) | H14B—C14—H14C | 109.5 |
C7—N1—N2—C9 | 9.01 (16) | C12—N3—C8—C9 | 67.6 (2) |
C1—N1—N2—C9 | 161.31 (13) | C12—N3—C8—C7 | −108.89 (18) |
C7—N1—N2—C11 | 151.05 (14) | O1—C7—C8—C9 | −177.01 (16) |
C1—N1—N2—C11 | −56.66 (19) | N1—C7—C8—C9 | 1.68 (16) |
C7—N1—C1—C2 | −64.2 (2) | O1—C7—C8—N3 | 0.0 (3) |
N2—N1—C1—C2 | 147.71 (14) | N1—C7—C8—N3 | 178.73 (13) |
C7—N1—C1—C6 | 113.91 (17) | N3—C8—C9—N2 | −172.97 (14) |
N2—N1—C1—C6 | −34.2 (2) | C7—C8—C9—N2 | 3.95 (18) |
C6—C1—C2—C3 | −0.7 (2) | N3—C8—C9—C10 | 8.5 (3) |
N1—C1—C2—C3 | 177.40 (15) | C7—C8—C9—C10 | −174.57 (18) |
C1—C2—C3—C4 | 0.4 (3) | N1—N2—C9—C8 | −7.90 (17) |
C2—C3—C4—C5 | 0.5 (3) | C11—N2—C9—C8 | −146.82 (15) |
C3—C4—C5—C6 | −1.0 (3) | N1—N2—C9—C10 | 170.73 (16) |
C2—C1—C6—C5 | 0.2 (2) | C11—N2—C9—C10 | 31.8 (3) |
N1—C1—C6—C5 | −177.87 (15) | C8—N3—C12—O2 | −8.1 (3) |
C4—C5—C6—C1 | 0.7 (3) | C8—N3—C12—O3 | 173.51 (13) |
N2—N1—C7—O1 | 172.30 (14) | C13—O3—C12—O2 | 6.8 (3) |
C1—N1—C7—O1 | 21.3 (2) | C13—O3—C12—N3 | −174.78 (15) |
N2—N1—C7—C8 | −6.52 (16) | C12—O3—C13—C14 | −173.5 (2) |
C1—N1—C7—C8 | −157.55 (14) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1i | 0.86 | 1.99 | 2.8223 (17) | 164 |
C10—H10A···O1ii | 0.96 | 2.56 | 3.343 (2) | 139 |
C11—H11B···O2iii | 0.96 | 2.66 | 3.576 (2) | 161 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, −y+1/2, z−1/2; (iii) x+1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···O1i | 0.86 | 1.99 | 2.8223 (17) | 163.6 |
C10—H10A···O1ii | 0.96 | 2.56 | 3.343 (2) | 139.3 |
C11—H11B···O2iii | 0.96 | 2.66 | 3.576 (2) | 160.7 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, −y+1/2, z−1/2; (iii) x+1, y, z. |
Acknowledgements
The authors acknowledge the provision of funds for purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.
References
Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Li, Y., Liu, Y., Wang, H., Xiong, X., Wei, P. & Li, F. (2013). Molecules, 18, 877–893. CSD CrossRef CAS PubMed Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
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The title compound (I), (Fig. 1) has been synthesized to examine its DNA binding potential and anti-microbial activity. The crystal structures of two closely related compounds, methyl (1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H- pyrazol-4-yl)carbamate and methyl (1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)methylcarbamate monohydrate have been reported previously (Li et al., 2013).
In (I), the C1—C6 benzene ring and dihydropyrazol-3-one system, O1/N1/N2/N3/C7—C9 are planar with r.m.s. deviations of 0.0037 and 0.0398 Å, respectively. The dihedral angle between the two systems is 53.64 (5)°. The ethyl ester group, C12/C13/C14/O2/O3, is also planar (r.m.s. deviation 0.0568 Å) and subtends an angle 67.73 (8)° to the pyrazole ring. In the crystal structure classical N3—H3A···O1 hydrogen bonds form inversion dimers (Table 1, Fig. 2) with R22(10) ring motifs. Weaker C10–H10A···O1 and C11–H11B···O2 contacts link these dimers into a three dimensional network of molecules stacked along the a axis direction. Offset π···π stacking interactions between the benzene rings with Cg2···Cg2i = 3.8832 (12) Å further stabilise the crystal packing (Cg2 is the centroid of the C1—C6 benzene ring; i = 2 - x, -y, 1 - z).