organic compounds
3-[3-(4-Bromophenyl)-1-phenyl-1H-pyrazol-4-yl]-5-ethoxy-2-phenylisoxazolidine
aCentre for Advanced Studies in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and bOrganic Chemistry Division, Central Leather Research Institute, Adyar, Chennai 600 020, India
*Correspondence e-mail: gurushan48@yahoo.com
In the title compound, C26H24BrN3O2, the isoxazolidine ring adopts an the ring N atom deviating from the mean plane of the other four atoms by an angle of 0.286°. The orientation of the phenyl ring is +sp and the bromophenyl ring is +sc relative to the attached pyrazole ring; the dihedral angles between the least-squares planes of the pyrazole and the attached phenyl and bromophenyl rings are 21.8 (3) and 41.8 (3)°.
Related literature
For related literature, see: Allen et al. (1987); Gayathri et al. (2007); Frederickson (1997); Gothelf et al. (2002); Huisgen (1984); Kumar et al. (2003).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2004); cell SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PARST97 (Nardelli, 1995).
Supporting information
https://doi.org/10.1107/S1600536807064938/lw2049sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807064938/lw2049Isup2.hkl
A solution of pyrazole nitrone (0.5 mmol) and ethyl vinyl ether (5 mmol) was refluxed in dry toluene (10 mL) at 60°C until the completion of the reaction as evidenced by
The solvent was evaporated under reduced pressure. The crude was purified by using ethyl acetate-petroleum ether (3:97) as to afford the pure isoxazolidine (68%) as a white solid. Single crystals were obtained by crystallization from petroleum ether and ethyl acetate mixture.The 1,3-dipolar cycloadditionof
to provides a straight forward route to isoxazolidines(Frederickson, 1997, Gothelf et al., 2002). The nitrone cycloadducts are attractive intermediates for the synthesis of several class of natural products and biologically active compounds such as b-aminoacids and alkaloids.(Huisgen, 1984).The pyrazole unit is the core structure in a number of natural products. Many pyrazole derivatives are known to exhibit a wide range of biological properties such as anti-hyperglycemic, analgesic, anti-inflammatory, anti-pyretic, anti-bacterial, hypoglycemic, sedative, hypnotic activity, and anticoagulant activity. Particularly, arylpyrazoles are widely used in medicinal and pesticidal chemistry. Recently some arylpyrazoles were reported to display non-nucleoside HIV-1 reverse transcriptase inhibitory activity (Kumar et al., 2003).The isoxazolidine ring adopts
with N as the flap, atom N7 deviates from the mean plane with a maximum deviation of 0.286 (2)°. The ethoxy group attached to the isoxazolidine adopts an extended conformation. The bond lengths and bond angles are comparable with literature values (Allen et al.,1987).The dihedral angle between the LSQ planes of pyrazole and phenyl and bromo phenyl ring is 21.8 (3)° and 41.8 (3)°, which is lower than the reported value due to the simple substitution of a bromine to the phenyl ring (Gayathri et al.,2007). The phenyl ring is equatorially substituted to the isoxazolidine ring and slightly twisted due to the steric hinderance with the bromophenyl ring and the ethoxy group is substituted axailly to the isoxazolidine ring. The molecule iss stabilized by intra molecular C—H···O hydrogen bonds in the unit cell.For related literature, see: Allen et al. (1987); Gayathri et al. (2007); Frederickson (1997); Gothelf et al. (2002); Huisgen (1984); Kumar et al. (2003).
Data collection: APEX2 (Bruker, 2004); cell
SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997), PARST97 (Nardelli, 1995).Fig. 1. The ORTEP diagram of the title compound with 30% probability displacement ellipsoids. | |
Fig. 2. Packing of the molecules viewed down c axis. |
C26H24BrN3O2 | F(000) = 2016 |
Mr = 490.39 | Dx = 1.417 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 4982 reflections |
a = 27.7493 (6) Å | θ = 2.9–27.0° |
b = 7.4254 (2) Å | µ = 1.82 mm−1 |
c = 24.5230 (5) Å | T = 293 K |
β = 114.516 (1)° | Cubic, yellow |
V = 4597.41 (18) Å3 | 0.26 × 0.23 × 0.22 mm |
Z = 8 |
Bruker Kappa APEXII diffractometer | 4982 independent reflections |
Radiation source: fine-focus sealed tube | 3038 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
ω and φ scans | θmax = 27.0°, θmin = 2.9° |
Absorption correction: multi-scan (SAINT; Bruker, 1999) | h = −35→35 |
Tmin = 0.650, Tmax = 0.691 | k = −9→9 |
23867 measured reflections | l = −31→31 |
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)] = 0.036 | H-atom parameters constrained |
wR(F2) = 0.096 | w = 1/[σ2(Fo2) + (0.0394P)2 + 2.7695P] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max = 0.004 |
4982 reflections | Δρmax = 0.37 e Å−3 |
289 parameters | Δρmin = −0.49 e Å−3 |
0 restraints | Extinction correction: SHELXL |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0028 (11) |
C26H24BrN3O2 | V = 4597.41 (18) Å3 |
Mr = 490.39 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 27.7493 (6) Å | µ = 1.82 mm−1 |
b = 7.4254 (2) Å | T = 293 K |
c = 24.5230 (5) Å | 0.26 × 0.23 × 0.22 mm |
β = 114.516 (1)° |
Bruker Kappa APEXII diffractometer | 4982 independent reflections |
Absorption correction: multi-scan (SAINT; Bruker, 1999) | 3038 reflections with I > 2σ(I) |
Tmin = 0.650, Tmax = 0.691 | Rint = 0.041 |
23867 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.096 | H-atom parameters constrained |
S = 1.00 | Δρmax = 0.37 e Å−3 |
4982 reflections | Δρmin = −0.49 e Å−3 |
289 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 | ||
Br1 | 1.015166 (12) | 0.61394 (5) | 0.097949 (17) | 0.09166 (16) | |
N1 | 0.76772 (7) | 0.4888 (2) | 0.08475 (8) | 0.0420 (4) | |
N2 | 0.72795 (7) | 0.4783 (2) | 0.10324 (8) | 0.0412 (4) | |
C3 | 0.74697 (9) | 0.4845 (3) | 0.16353 (10) | 0.0436 (5) | |
H3 | 0.7268 | 0.4794 | 0.1857 | 0.052* | |
C4 | 0.80068 (9) | 0.4996 (3) | 0.18641 (9) | 0.0388 (5) | |
C5 | 0.81190 (9) | 0.5021 (3) | 0.13506 (9) | 0.0381 (5) | |
C11 | 0.67491 (9) | 0.4517 (3) | 0.06083 (10) | 0.0419 (5) | |
C16 | 0.66488 (10) | 0.3876 (3) | 0.00433 (11) | 0.0531 (6) | |
H7 | 0.6926 | 0.3660 | −0.0067 | 0.064* | |
C15 | 0.61347 (11) | 0.3559 (3) | −0.03539 (13) | 0.0661 (7) | |
H8 | 0.6066 | 0.3131 | −0.0736 | 0.079* | |
C14 | 0.57219 (11) | 0.3861 (4) | −0.01980 (14) | 0.0699 (8) | |
H9 | 0.5376 | 0.3615 | −0.0468 | 0.084* | |
C13 | 0.58227 (10) | 0.4529 (4) | 0.03587 (14) | 0.0650 (7) | |
H10 | 0.5543 | 0.4749 | 0.0465 | 0.078* | |
C12 | 0.63349 (10) | 0.4881 (3) | 0.07642 (11) | 0.0524 (6) | |
H11 | 0.6400 | 0.5359 | 0.1139 | 0.063* | |
C6 | 0.83710 (9) | 0.5082 (3) | 0.25106 (9) | 0.0400 (5) | |
H6 | 0.8732 | 0.5337 | 0.2555 | 0.048* | |
N7 | 0.83638 (7) | 0.3344 (2) | 0.28223 (7) | 0.0396 (4) | |
O8 | 0.86261 (6) | 0.3879 (2) | 0.34526 (6) | 0.0474 (4) | |
C9 | 0.83812 (9) | 0.5532 (3) | 0.34867 (10) | 0.0446 (5) | |
H9A | 0.8637 | 0.6299 | 0.3798 | 0.054* | |
C10 | 0.82134 (10) | 0.6428 (3) | 0.28798 (10) | 0.0497 (6) | |
H10A | 0.8396 | 0.7565 | 0.2916 | 0.060* | |
H10B | 0.7834 | 0.6642 | 0.2698 | 0.060* | |
C17 | 0.86907 (9) | 0.1977 (3) | 0.27316 (10) | 0.0412 (5) | |
C22 | 0.84549 (10) | 0.0922 (3) | 0.22259 (11) | 0.0521 (6) | |
H18 | 0.8098 | 0.1067 | 0.1976 | 0.062* | |
C21 | 0.87546 (12) | −0.0354 (3) | 0.20937 (13) | 0.0642 (7) | |
H19 | 0.8600 | −0.1039 | 0.1746 | 0.077* | |
C20 | 0.92747 (13) | −0.0614 (4) | 0.24692 (15) | 0.0718 (8) | |
H20 | 0.9473 | −0.1480 | 0.2380 | 0.086* | |
C19 | 0.95026 (11) | 0.0402 (4) | 0.29764 (14) | 0.0718 (8) | |
H21 | 0.9856 | 0.0217 | 0.3234 | 0.086* | |
C18 | 0.92128 (10) | 0.1703 (3) | 0.31106 (12) | 0.0573 (6) | |
H22 | 0.9371 | 0.2391 | 0.3457 | 0.069* | |
O23 | 0.79337 (6) | 0.5295 (2) | 0.35987 (6) | 0.0468 (4) | |
C24 | 0.80487 (10) | 0.4624 (3) | 0.41873 (10) | 0.0504 (6) | |
H24A | 0.8319 | 0.5358 | 0.4486 | 0.060* | |
H24B | 0.8177 | 0.3395 | 0.4226 | 0.060* | |
C25 | 0.75456 (11) | 0.4695 (4) | 0.42755 (12) | 0.0703 (8) | |
H25A | 0.7610 | 0.4249 | 0.4667 | 0.106* | |
H25B | 0.7281 | 0.3964 | 0.3977 | 0.106* | |
H25C | 0.7423 | 0.5917 | 0.4238 | 0.106* | |
C26 | 0.86227 (9) | 0.5288 (3) | 0.12921 (9) | 0.0387 (5) | |
C31 | 0.86189 (9) | 0.6344 (3) | 0.08219 (10) | 0.0456 (5) | |
H27 | 0.8305 | 0.6888 | 0.0564 | 0.055* | |
C30 | 0.90731 (10) | 0.6599 (3) | 0.07315 (11) | 0.0522 (6) | |
H28 | 0.9065 | 0.7291 | 0.0412 | 0.063* | |
C29 | 0.95350 (9) | 0.5817 (3) | 0.11189 (11) | 0.0513 (6) | |
C28 | 0.95552 (10) | 0.4791 (3) | 0.15916 (11) | 0.0544 (6) | |
H30 | 0.9873 | 0.4282 | 0.1854 | 0.065* | |
C27 | 0.90973 (9) | 0.4523 (3) | 0.16740 (10) | 0.0463 (6) | |
H31 | 0.9108 | 0.3815 | 0.1992 | 0.056* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0616 (2) | 0.1079 (3) | 0.1308 (3) | 0.00190 (17) | 0.0650 (2) | 0.0236 (2) |
N1 | 0.0463 (11) | 0.0463 (10) | 0.0442 (11) | −0.0036 (9) | 0.0296 (10) | −0.0001 (8) |
N2 | 0.0440 (11) | 0.0436 (10) | 0.0436 (11) | −0.0031 (8) | 0.0258 (9) | 0.0021 (8) |
C3 | 0.0515 (14) | 0.0448 (12) | 0.0477 (14) | −0.0017 (11) | 0.0339 (12) | 0.0042 (10) |
C4 | 0.0502 (13) | 0.0355 (11) | 0.0404 (13) | 0.0000 (10) | 0.0285 (11) | 0.0015 (9) |
C5 | 0.0443 (13) | 0.0354 (11) | 0.0412 (13) | 0.0000 (10) | 0.0244 (11) | −0.0008 (9) |
C11 | 0.0444 (13) | 0.0365 (11) | 0.0470 (14) | −0.0043 (10) | 0.0211 (11) | 0.0043 (10) |
C16 | 0.0518 (15) | 0.0544 (14) | 0.0553 (16) | −0.0006 (12) | 0.0246 (13) | −0.0019 (12) |
C15 | 0.0646 (18) | 0.0661 (17) | 0.0582 (17) | −0.0037 (14) | 0.0160 (15) | −0.0105 (13) |
C14 | 0.0498 (16) | 0.0674 (17) | 0.080 (2) | −0.0050 (14) | 0.0147 (15) | 0.0006 (15) |
C13 | 0.0474 (16) | 0.0686 (17) | 0.085 (2) | 0.0019 (13) | 0.0329 (16) | 0.0117 (15) |
C12 | 0.0518 (15) | 0.0547 (14) | 0.0589 (15) | −0.0013 (12) | 0.0311 (13) | 0.0020 (12) |
C6 | 0.0496 (13) | 0.0389 (11) | 0.0418 (13) | −0.0025 (10) | 0.0291 (11) | −0.0011 (10) |
N7 | 0.0501 (11) | 0.0415 (9) | 0.0329 (10) | 0.0028 (8) | 0.0231 (9) | 0.0001 (8) |
O8 | 0.0559 (10) | 0.0548 (9) | 0.0356 (9) | 0.0104 (8) | 0.0229 (8) | −0.0017 (7) |
C9 | 0.0498 (14) | 0.0482 (13) | 0.0425 (13) | −0.0005 (11) | 0.0258 (11) | −0.0080 (10) |
C10 | 0.0710 (16) | 0.0422 (12) | 0.0487 (14) | 0.0039 (11) | 0.0377 (13) | 0.0000 (10) |
C17 | 0.0507 (14) | 0.0369 (11) | 0.0472 (13) | 0.0000 (10) | 0.0314 (12) | 0.0036 (10) |
C22 | 0.0604 (15) | 0.0440 (13) | 0.0570 (16) | −0.0029 (11) | 0.0296 (13) | −0.0065 (11) |
C21 | 0.081 (2) | 0.0482 (14) | 0.0740 (19) | −0.0064 (14) | 0.0422 (17) | −0.0176 (13) |
C20 | 0.080 (2) | 0.0531 (16) | 0.100 (2) | 0.0077 (15) | 0.055 (2) | −0.0111 (16) |
C19 | 0.0570 (17) | 0.0723 (18) | 0.086 (2) | 0.0146 (15) | 0.0292 (16) | −0.0078 (17) |
C18 | 0.0571 (16) | 0.0554 (14) | 0.0623 (17) | 0.0067 (12) | 0.0276 (14) | −0.0070 (12) |
O23 | 0.0522 (10) | 0.0572 (9) | 0.0387 (9) | 0.0068 (8) | 0.0266 (8) | 0.0029 (7) |
C24 | 0.0676 (16) | 0.0511 (13) | 0.0409 (13) | 0.0092 (12) | 0.0310 (12) | 0.0044 (11) |
C25 | 0.080 (2) | 0.0892 (19) | 0.0590 (17) | 0.0074 (16) | 0.0456 (16) | 0.0151 (15) |
C26 | 0.0464 (13) | 0.0383 (11) | 0.0402 (12) | −0.0014 (10) | 0.0268 (11) | −0.0049 (10) |
C31 | 0.0464 (13) | 0.0485 (13) | 0.0481 (14) | 0.0030 (11) | 0.0259 (11) | 0.0058 (11) |
C30 | 0.0579 (16) | 0.0517 (14) | 0.0611 (16) | −0.0013 (12) | 0.0388 (14) | 0.0091 (12) |
C29 | 0.0469 (14) | 0.0543 (14) | 0.0665 (16) | −0.0033 (12) | 0.0372 (13) | −0.0011 (12) |
C28 | 0.0444 (14) | 0.0663 (16) | 0.0545 (16) | 0.0064 (12) | 0.0224 (13) | 0.0017 (13) |
C27 | 0.0536 (15) | 0.0515 (13) | 0.0419 (13) | 0.0042 (11) | 0.0277 (12) | 0.0037 (10) |
Br1—C29 | 1.894 (2) | C10—H10A | 0.9700 |
N1—C5 | 1.334 (3) | C10—H10B | 0.9700 |
N1—N2 | 1.358 (2) | C17—C18 | 1.374 (3) |
N2—C3 | 1.349 (3) | C17—C22 | 1.381 (3) |
N2—C11 | 1.420 (3) | C22—C21 | 1.385 (3) |
C3—C4 | 1.362 (3) | C22—H18 | 0.9300 |
C3—H3 | 0.9300 | C21—C20 | 1.366 (4) |
C4—C5 | 1.417 (3) | C21—H19 | 0.9300 |
C4—C6 | 1.486 (3) | C20—C19 | 1.365 (4) |
C5—C26 | 1.476 (3) | C20—H20 | 0.9300 |
C11—C16 | 1.380 (3) | C19—C18 | 1.381 (3) |
C11—C12 | 1.380 (3) | C19—H21 | 0.9300 |
C16—C15 | 1.373 (4) | C18—H22 | 0.9300 |
C16—H7 | 0.9300 | O23—C24 | 1.432 (2) |
C15—C14 | 1.369 (4) | C24—C25 | 1.500 (3) |
C15—H8 | 0.9300 | C24—H24A | 0.9700 |
C14—C13 | 1.368 (4) | C24—H24B | 0.9700 |
C14—H9 | 0.9300 | C25—H25A | 0.9600 |
C13—C12 | 1.380 (3) | C25—H25B | 0.9600 |
C13—H10 | 0.9300 | C25—H25C | 0.9600 |
C12—H11 | 0.9300 | C26—C27 | 1.382 (3) |
C6—N7 | 1.504 (3) | C26—C31 | 1.391 (3) |
C6—C10 | 1.529 (3) | C31—C30 | 1.380 (3) |
C6—H6 | 0.9800 | C31—H27 | 0.9300 |
N7—C17 | 1.439 (3) | C30—C29 | 1.368 (3) |
N7—O8 | 1.464 (2) | C30—H28 | 0.9300 |
O8—C9 | 1.422 (3) | C29—C28 | 1.369 (3) |
C9—O23 | 1.390 (2) | C28—C27 | 1.381 (3) |
C9—C10 | 1.516 (3) | C28—H30 | 0.9300 |
C9—H9A | 0.9800 | C27—H31 | 0.9300 |
C5—N1—N2 | 104.94 (16) | C6—C10—H10B | 110.9 |
C3—N2—N1 | 111.19 (17) | H10A—C10—H10B | 108.9 |
C3—N2—C11 | 128.51 (17) | C18—C17—C22 | 119.8 (2) |
N1—N2—C11 | 120.16 (17) | C18—C17—N7 | 123.8 (2) |
N2—C3—C4 | 108.54 (17) | C22—C17—N7 | 116.4 (2) |
N2—C3—H3 | 125.7 | C17—C22—C21 | 119.4 (2) |
C4—C3—H3 | 125.7 | C17—C22—H18 | 120.3 |
C3—C4—C5 | 103.97 (18) | C21—C22—H18 | 120.3 |
C3—C4—C6 | 125.90 (18) | C20—C21—C22 | 120.5 (3) |
C5—C4—C6 | 130.13 (19) | C20—C21—H19 | 119.7 |
N1—C5—C4 | 111.36 (18) | C22—C21—H19 | 119.7 |
N1—C5—C26 | 117.65 (17) | C19—C20—C21 | 119.8 (2) |
C4—C5—C26 | 130.8 (2) | C19—C20—H20 | 120.1 |
C16—C11—C12 | 120.1 (2) | C21—C20—H20 | 120.1 |
C16—C11—N2 | 119.9 (2) | C20—C19—C18 | 120.5 (3) |
C12—C11—N2 | 119.9 (2) | C20—C19—H21 | 119.7 |
C15—C16—C11 | 119.3 (2) | C18—C19—H21 | 119.7 |
C15—C16—H7 | 120.4 | C17—C18—C19 | 119.8 (2) |
C11—C16—H7 | 120.4 | C17—C18—H22 | 120.1 |
C14—C15—C16 | 121.2 (3) | C19—C18—H22 | 120.1 |
C14—C15—H8 | 119.4 | C9—O23—C24 | 113.54 (17) |
C16—C15—H8 | 119.4 | O23—C24—C25 | 107.5 (2) |
C13—C14—C15 | 119.3 (3) | O23—C24—H24A | 110.2 |
C13—C14—H9 | 120.3 | C25—C24—H24A | 110.2 |
C15—C14—H9 | 120.3 | O23—C24—H24B | 110.2 |
C14—C13—C12 | 120.7 (2) | C25—C24—H24B | 110.2 |
C14—C13—H10 | 119.6 | H24A—C24—H24B | 108.5 |
C12—C13—H10 | 119.6 | C24—C25—H25A | 109.5 |
C13—C12—C11 | 119.4 (2) | C24—C25—H25B | 109.5 |
C13—C12—H11 | 120.3 | H25A—C25—H25B | 109.5 |
C11—C12—H11 | 120.3 | C24—C25—H25C | 109.5 |
C4—C6—N7 | 111.02 (16) | H25A—C25—H25C | 109.5 |
C4—C6—C10 | 115.13 (18) | H25B—C25—H25C | 109.5 |
N7—C6—C10 | 101.09 (15) | C27—C26—C31 | 118.09 (19) |
C4—C6—H6 | 109.8 | C27—C26—C5 | 123.58 (19) |
N7—C6—H6 | 109.8 | C31—C26—C5 | 118.3 (2) |
C10—C6—H6 | 109.8 | C30—C31—C26 | 121.1 (2) |
C17—N7—O8 | 106.59 (15) | C30—C31—H27 | 119.4 |
C17—N7—C6 | 112.61 (15) | C26—C31—H27 | 119.4 |
O8—N7—C6 | 101.43 (14) | C29—C30—C31 | 119.0 (2) |
C9—O8—N7 | 104.82 (14) | C29—C30—H28 | 120.5 |
O23—C9—O8 | 112.99 (18) | C31—C30—H28 | 120.5 |
O23—C9—C10 | 108.29 (19) | C30—C29—C28 | 121.4 (2) |
O8—C9—C10 | 106.28 (16) | C30—C29—Br1 | 118.51 (17) |
O23—C9—H9A | 109.7 | C28—C29—Br1 | 120.05 (19) |
O8—C9—H9A | 109.7 | C29—C28—C27 | 119.2 (2) |
C10—C9—H9A | 109.7 | C29—C28—H30 | 120.4 |
C9—C10—C6 | 104.34 (17) | C27—C28—H30 | 120.4 |
C9—C10—H10A | 110.9 | C28—C27—C26 | 121.1 (2) |
C6—C10—H10A | 110.9 | C28—C27—H31 | 119.4 |
C9—C10—H10B | 110.9 | C26—C27—H31 | 119.4 |
C5—N1—N2—C3 | −0.1 (2) | N7—O8—C9—C10 | −29.9 (2) |
C5—N1—N2—C11 | −176.21 (17) | O23—C9—C10—C6 | −119.66 (19) |
N1—N2—C3—C4 | 0.0 (2) | O8—C9—C10—C6 | 2.0 (2) |
C11—N2—C3—C4 | 175.68 (19) | C4—C6—C10—C9 | 145.05 (18) |
N2—C3—C4—C5 | 0.1 (2) | N7—C6—C10—C9 | 25.3 (2) |
N2—C3—C4—C6 | −179.11 (18) | O8—N7—C17—C18 | −18.5 (3) |
N2—N1—C5—C4 | 0.2 (2) | C6—N7—C17—C18 | 91.9 (2) |
N2—N1—C5—C26 | −175.78 (17) | O8—N7—C17—C22 | 162.37 (17) |
C3—C4—C5—N1 | −0.2 (2) | C6—N7—C17—C22 | −87.3 (2) |
C6—C4—C5—N1 | 178.98 (19) | C18—C17—C22—C21 | −2.7 (3) |
C3—C4—C5—C26 | 175.1 (2) | N7—C17—C22—C21 | 176.5 (2) |
C6—C4—C5—C26 | −5.7 (4) | C17—C22—C21—C20 | 2.2 (4) |
C3—N2—C11—C16 | −157.4 (2) | C22—C21—C20—C19 | −0.5 (4) |
N1—N2—C11—C16 | 17.9 (3) | C21—C20—C19—C18 | −0.6 (4) |
C3—N2—C11—C12 | 21.8 (3) | C22—C17—C18—C19 | 1.6 (4) |
N1—N2—C11—C12 | −162.82 (19) | N7—C17—C18—C19 | −177.5 (2) |
C12—C11—C16—C15 | −1.8 (3) | C20—C19—C18—C17 | 0.1 (4) |
N2—C11—C16—C15 | 177.5 (2) | O8—C9—O23—C24 | 68.5 (2) |
C11—C16—C15—C14 | −0.3 (4) | C10—C9—O23—C24 | −174.05 (17) |
C16—C15—C14—C13 | 1.5 (4) | C9—O23—C24—C25 | 171.8 (2) |
C15—C14—C13—C12 | −0.7 (4) | N1—C5—C26—C27 | −143.2 (2) |
C14—C13—C12—C11 | −1.4 (4) | C4—C5—C26—C27 | 41.8 (3) |
C16—C11—C12—C13 | 2.6 (3) | N1—C5—C26—C31 | 35.7 (3) |
N2—C11—C12—C13 | −176.7 (2) | C4—C5—C26—C31 | −139.3 (2) |
C3—C4—C6—N7 | 65.4 (3) | C27—C26—C31—C30 | 1.1 (3) |
C5—C4—C6—N7 | −113.6 (2) | C5—C26—C31—C30 | −177.9 (2) |
C3—C4—C6—C10 | −48.7 (3) | C26—C31—C30—C29 | −1.0 (3) |
C5—C4—C6—C10 | 132.3 (2) | C31—C30—C29—C28 | 0.1 (4) |
C4—C6—N7—C17 | 80.7 (2) | C31—C30—C29—Br1 | 178.75 (17) |
C10—C6—N7—C17 | −156.73 (18) | C30—C29—C28—C27 | 0.8 (4) |
C4—C6—N7—O8 | −165.78 (15) | Br1—C29—C28—C27 | −177.84 (18) |
C10—C6—N7—O8 | −43.17 (19) | C29—C28—C27—C26 | −0.8 (4) |
C17—N7—O8—C9 | 164.37 (15) | C31—C26—C27—C28 | −0.2 (3) |
C6—N7—O8—C9 | 46.37 (17) | C5—C26—C27—C28 | 178.8 (2) |
N7—O8—C9—O23 | 88.77 (19) |
Experimental details
Crystal data | |
Chemical formula | C26H24BrN3O2 |
Mr | 490.39 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 293 |
a, b, c (Å) | 27.7493 (6), 7.4254 (2), 24.5230 (5) |
β (°) | 114.516 (1) |
V (Å3) | 4597.41 (18) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 1.82 |
Crystal size (mm) | 0.26 × 0.23 × 0.22 |
Data collection | |
Diffractometer | Bruker Kappa APEXII |
Absorption correction | Multi-scan (SAINT; Bruker, 1999) |
Tmin, Tmax | 0.650, 0.691 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 23867, 4982, 3038 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.638 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.096, 1.00 |
No. of reflections | 4982 |
No. of parameters | 289 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.37, −0.49 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 (Sheldrick, 1997), PARST97 (Nardelli, 1995).
Acknowledgements
SE thanks the Council of Scientific and Industrial Research (CSIR), New Delhi, for providing financial assistance as a Senior Research Fellowship (SRF).
References
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The 1,3-dipolar cycloadditionof nitrones to alkenes provides a straight forward route to isoxazolidines(Frederickson, 1997, Gothelf et al., 2002). The nitrone cycloadducts are attractive intermediates for the synthesis of several class of natural products and biologically active compounds such as b-aminoacids and alkaloids.(Huisgen, 1984).The pyrazole unit is the core structure in a number of natural products. Many pyrazole derivatives are known to exhibit a wide range of biological properties such as anti-hyperglycemic, analgesic, anti-inflammatory, anti-pyretic, anti-bacterial, hypoglycemic, sedative, hypnotic activity, and anticoagulant activity. Particularly, arylpyrazoles are widely used in medicinal and pesticidal chemistry. Recently some arylpyrazoles were reported to display non-nucleoside HIV-1 reverse transcriptase inhibitory activity (Kumar et al., 2003).
The isoxazolidine ring adopts envelope conformation with N as the flap, atom N7 deviates from the mean plane with a maximum deviation of 0.286 (2)°. The ethoxy group attached to the isoxazolidine adopts an extended conformation. The bond lengths and bond angles are comparable with literature values (Allen et al.,1987).The dihedral angle between the LSQ planes of pyrazole and phenyl and bromo phenyl ring is 21.8 (3)° and 41.8 (3)°, which is lower than the reported value due to the simple substitution of a bromine to the phenyl ring (Gayathri et al.,2007). The phenyl ring is equatorially substituted to the isoxazolidine ring and slightly twisted due to the steric hinderance with the bromophenyl ring and the ethoxy group is substituted axailly to the isoxazolidine ring. The molecule iss stabilized by intra molecular C—H···O hydrogen bonds in the unit cell.