research communications
of 2-isopropyl-4-methoxy-5-methylphenyl 4-methylbenzenesulfonate
aLaboratoire de Physico-Chimie Moléculaire et Synthèse Organique, Département de Chimie, Faculté des Sciences, Semlalia BP 2390, Marrakech 40001, Morocco, bLaboratoire de Chimie de Coordination, CNRS UPR8241, 205 route de Narbonne, 31077 Toulouse Cedex 04, France, and cLaboratoire de Chimie Organique et Analytique, Faculté des Sciences et, Techniques, Université Sultan Moulay Slimane, BP 523, 23000 Béni-Mellal, Morocco
*Correspondence e-mail: a.auhmani@uca.ma
The title compound, C18H22O4S, an hemisynthetic product, was obtained by the tosylation reaction of the naturally occurring meroterpene p-methoxythymol. The molecule comprises a tetrasubstitued phenyl ring linked to a toluenesulfonate through one of its O atoms. In the crystal, C—H⋯O and C—H⋯π interactions link the molecules, forming a three-dimensional network.
CCDC reference: 1825267
1. Chemical context
Tosylation of p-toluene sulfonyl chloride, which is very reactive (Greene & Wuts, 1999; Yoshida et al., 1999). Tosylate is an important in organic synthesis as it makes a good (Wagner & Zokk, 1955; Sandler & Karo, 1983). Indeed, tosylates are used as intermediates in the synthesis of several drugs (Kim et al., 1995; Morgan et al., 1997). Furthermore, they have also been found to possess important biological activities (Kacem et al., 2002; Kaleemullah et al., 2012).
is an important transformation in organic synthesis. This transformation is usually achieved withThe hemisynthesis of 2-isopropyl-4-methoxy-5-methylphenyl 4-methylbenzenesulfonate 2 from naturally occurring p-methoxythymol 1 was undertaken with the aim of preparing meroterpenic tosylate. X-ray single-crystal structure analysis allowed its full structure to be confirmed unambiguously.
2. Structural commentary
Compound 2 is built up from a tetrasubstituted phenyl ring linked to a toluenesulfonate unit through one of its oxygen atoms (Fig. 1). The two phenyl rings form a dihedral angle of 60.03 (9)°. Atoms S1 and C5′ are coplanar with the C1′–C6′ phenyl ring, their distances from the plane being 0.057 (3) and 0.031 (3) Å, respectively. Considering the connected atoms of the four substituents on the C1–C6 phenyl ring, three of them O2, C8 and C11 are roughly in the plane of the phenyl ring, deviating by only 0.011 (3), 0.014 (3) and 0.012 (3) Å, respectively, from the mean plane, whereas atom O1 is displaced slightly out of the plane by 0.101 (3) Å. This slight distortion might be related to the occurrence of a weak C—H⋯π interaction between the C9 atom and the centroid Cg2 of the C1′–C6′ phenyl ring (Table 1).
3. Supramolecular features
In the crystal, pairs of molecules are linked though C—H⋯O interactions (Table 1), forming pseudo-dimer arranged around inversion centers (Fig. 2). Further C—H⋯O hydrogen bonds and C—H⋯π interactions (Table 1, Fig. 2) lead to the formation of a three-dimensional network.
4. Database survey
A search of the Cambridge Structural Database (CSD, version 5.38, last update May 2017; Groom et al., 2016) for a tosylate fragment bearing an organic substituent on one of its oxygen atoms revealed only three hits. Two of these compounds are closely related to compound 2. The first, 5-bromo-2,3-dimethylphenol-1-(4-methylphenylsulfonyloxy)benzene (KAWDAN; Niestroj et al., 1998), is built up from a tosylate attached to a phenyl ring substituted by two methyl groups and one bromine atom whereas the second, tetramethyl-p-phenylene p-ditoluenesulfonate (TMPDTS; Wieczorek et al., 1975), is built up from a tetramethyl-substituted phenyl ring attached to two tosylate units. A comparison of selected distances in compound 2 with those of two structures reveals that the geometries are very similar for all three compounds (Table 2). The most marked difference is the dihedral angle between the phenyl rings, 60.03 (9)° in 2 and 15.32 and 43.02° in KAWDAN and TMPDTS, respectively. The large dihedral angle in TMPDTS might be related to the occurrence of two bulky substituents on the central phenyl ring.
5. Synthesis and crystallization
In a 100mL flask, 430 mg (2.33mmol) of p-methoxythymol 1 were dissolved in 15 mL of pyridine and then 908 mg (4.66 mmol) of para-toluenesulfonyl chloride were added. The reaction mixture was heated to reflux for two h. The end of the reaction was controlled by TLC. The reaction mixture was washed with a hydrochloric acid solution (0.1 M) to neutral pH, extracted three times with ethyl ether (3 × 20 mL), dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified by silica gel using hexane/ethyl acetate (94:6) as to give 360 mg (1.07 mmol, 46% yield) of 2-isopropyl-4-methoxy-5-methylphenyl 4-methylbenzenesulfonate 2. X-ray quality colourless crystals were obtained by slow evaporation of a petroleum ether solution of the title compound.
NMR data for compound 2: 1H NMR (300 MHz, CDCl3): 6.66 (s, H-6), 6.84 (s, H-3), 3.45 (sept, H-8), 1.09 (d, H-9,H-10), 2.13 (s, H-7), 3.72 (s, H-10), 7.33 (d, H-3′), 7.75 (d, H-2′), 2.43 (s, H-5′) ppm. 13C NMR (75 MHz, CDCl3): 156.4 (C-1), 124.0 (C-2), 107.5 (C-3), 145.2 (C-4), 139.8 (C-5), 124.1 (C-6),15.7 (C-7), 26.8 (C-8), 23.1 (C-9, C-10), 55.4 (OCH3), 145.2 (C-1′), 129.7 (C-2′), 128.4 (C-3′), 139.7 (C-4′), 21.5 (C-5′) ppm.
6. Refinement
Crystal data, data collection and structure . All H atoms were fixed geometrically and treated as riding with C—H = 1.0 (methine), 0.98 (methyl) or 0.95 Å (aromatic) with Uiso(H) = 1.2Ueq(CH and CH2) or Uiso(H) = 1.5Ueq(CH3).
details are summarized in Table 3
|
Supporting information
CCDC reference: 1825267
https://doi.org/10.1107/S2056989018003110/xu5919sup1.cif
contains datablocks I, global. DOI:Supporting information file. DOI: https://doi.org/10.1107/S2056989018003110/xu5919Isup3.cml
Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018003110/xu5919Isup3.hkl
Data collection: CrysAlis PRO (Rigaku OD, 2015); cell
CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015).C18H22O4S | F(000) = 712 |
Mr = 334.41 | Dx = 1.282 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 8.2226 (6) Å | Cell parameters from 4433 reflections |
b = 14.5382 (9) Å | θ = 3.8–28.5° |
c = 14.7230 (8) Å | µ = 0.20 mm−1 |
β = 100.020 (6)° | T = 173 K |
V = 1733.17 (19) Å3 | Box, colourless |
Z = 4 | 0.35 × 0.25 × 0.10 mm |
Rigaku Oxford Diffraction Xcalibur Eos Gemini ultra diffractometer | 3532 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 2777 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.044 |
Detector resolution: 16.1978 pixels mm-1 | θmax = 26.4°, θmin = 3.1° |
ω scans | h = −10→10 |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | k = −18→16 |
Tmin = 0.791, Tmax = 1.000 | l = −18→18 |
18172 measured reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.042 | H-atom parameters constrained |
wR(F2) = 0.110 | w = 1/[σ2(Fo2) + (0.0459P)2 + 0.814P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max < 0.001 |
3532 reflections | Δρmax = 0.34 e Å−3 |
213 parameters | Δρmin = −0.34 e Å−3 |
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. All H atoms attached to C atoms were fixed geometrically and treated as riding with C—H = 0.95 Å (aromatic), 0.98 Å (methyl), 1.0Å (methine) with Uiso(H) = 1.2Ueq(CH and C=CH) or Uiso(H) = 1.5Ueq(CH3). |
x | y | z | Uiso*/Ueq | ||
C1 | 0.0729 (2) | 0.19454 (12) | 0.12387 (12) | 0.0244 (4) | |
C1' | 0.2295 (2) | 0.11565 (13) | 0.32646 (12) | 0.0273 (4) | |
C2' | 0.2423 (2) | 0.02563 (13) | 0.29895 (13) | 0.0319 (4) | |
H2' | 0.150817 | −0.004394 | 0.262620 | 0.038* | |
C2 | 0.2184 (2) | 0.20290 (12) | 0.08959 (12) | 0.0253 (4) | |
C3' | 0.3907 (3) | −0.02031 (14) | 0.32514 (13) | 0.0351 (5) | |
H3' | 0.400221 | −0.082269 | 0.306238 | 0.042* | |
C3 | 0.2171 (2) | 0.16786 (13) | 0.00089 (12) | 0.0281 (4) | |
H3 | 0.314049 | 0.172671 | −0.025740 | 0.034* | |
C4 | 0.0786 (2) | 0.12650 (13) | −0.04881 (12) | 0.0283 (4) | |
C4' | 0.5259 (2) | 0.02225 (14) | 0.37844 (12) | 0.0323 (4) | |
C5 | −0.0681 (2) | 0.11891 (13) | −0.01288 (13) | 0.0293 (4) | |
C5' | 0.6862 (3) | −0.02793 (16) | 0.40828 (15) | 0.0414 (5) | |
H5'1 | 0.674385 | −0.091812 | 0.386905 | 0.062* | |
H5'2 | 0.714962 | −0.026864 | 0.475724 | 0.062* | |
H5'3 | 0.773618 | 0.002185 | 0.381667 | 0.062* | |
C6 | −0.0682 (2) | 0.15452 (13) | 0.07405 (13) | 0.0284 (4) | |
H6 | −0.166024 | 0.151593 | 0.100070 | 0.034* | |
C6' | 0.5098 (2) | 0.11365 (15) | 0.40381 (13) | 0.0356 (5) | |
H6' | 0.601735 | 0.144317 | 0.439007 | 0.043* | |
C7 | 0.4269 (3) | 0.32911 (16) | 0.09104 (15) | 0.0451 (6) | |
H7A | 0.459446 | 0.308452 | 0.033416 | 0.068* | |
H7B | 0.520807 | 0.359505 | 0.129571 | 0.068* | |
H7C | 0.334786 | 0.372516 | 0.077095 | 0.068* | |
C7' | 0.3633 (2) | 0.16037 (14) | 0.37888 (13) | 0.0325 (4) | |
H7' | 0.353664 | 0.222483 | 0.397271 | 0.039* | |
C8 | 0.3736 (2) | 0.24634 (14) | 0.14252 (13) | 0.0310 (4) | |
H8 | 0.349050 | 0.268405 | 0.203020 | 0.037* | |
C9 | 0.5123 (3) | 0.17540 (18) | 0.16200 (16) | 0.0483 (6) | |
H9A | 0.474804 | 0.122497 | 0.194085 | 0.072* | |
H9B | 0.608770 | 0.203173 | 0.200759 | 0.072* | |
H9C | 0.542309 | 0.155001 | 0.103658 | 0.072* | |
C10 | 0.2226 (3) | 0.08648 (18) | −0.17038 (15) | 0.0526 (7) | |
H10A | 0.261778 | 0.149089 | −0.178548 | 0.079* | |
H10B | 0.203927 | 0.054579 | −0.229920 | 0.079* | |
H10C | 0.305633 | 0.053107 | −0.126849 | 0.079* | |
C11 | −0.2193 (3) | 0.07531 (15) | −0.06830 (14) | 0.0388 (5) | |
H11A | −0.307373 | 0.073020 | −0.031237 | 0.058* | |
H11B | −0.192880 | 0.012726 | −0.085726 | 0.058* | |
H11C | −0.256290 | 0.111763 | −0.124059 | 0.058* | |
O1 | 0.06333 (15) | 0.23611 (8) | 0.21065 (8) | 0.0269 (3) | |
O2 | 0.07192 (18) | 0.09037 (10) | −0.13523 (9) | 0.0391 (4) | |
O3 | −0.08697 (16) | 0.10974 (10) | 0.27106 (10) | 0.0378 (3) | |
O4 | 0.02806 (17) | 0.24132 (10) | 0.36634 (9) | 0.0386 (4) | |
S1 | 0.04212 (6) | 0.17449 (3) | 0.29760 (3) | 0.02896 (14) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0260 (9) | 0.0203 (9) | 0.0269 (9) | 0.0030 (7) | 0.0041 (7) | 0.0025 (7) |
C1' | 0.0316 (9) | 0.0231 (10) | 0.0270 (9) | 0.0023 (8) | 0.0049 (7) | 0.0001 (7) |
C2' | 0.0354 (10) | 0.0247 (10) | 0.0349 (10) | −0.0030 (8) | 0.0038 (8) | −0.0036 (8) |
C2 | 0.0248 (9) | 0.0208 (9) | 0.0298 (9) | −0.0004 (7) | 0.0029 (7) | 0.0022 (7) |
C3' | 0.0445 (12) | 0.0226 (10) | 0.0392 (11) | 0.0032 (9) | 0.0098 (9) | −0.0032 (8) |
C3 | 0.0297 (9) | 0.0242 (10) | 0.0313 (9) | −0.0007 (8) | 0.0084 (7) | 0.0022 (8) |
C4 | 0.0363 (10) | 0.0210 (10) | 0.0262 (9) | 0.0000 (8) | 0.0016 (7) | 0.0025 (7) |
C4' | 0.0379 (11) | 0.0306 (11) | 0.0287 (9) | 0.0052 (9) | 0.0067 (8) | 0.0033 (8) |
C5 | 0.0301 (9) | 0.0206 (10) | 0.0349 (10) | −0.0003 (8) | −0.0013 (8) | 0.0063 (8) |
C5' | 0.0415 (12) | 0.0441 (13) | 0.0398 (11) | 0.0126 (10) | 0.0103 (9) | 0.0081 (10) |
C6 | 0.0230 (9) | 0.0255 (10) | 0.0366 (10) | 0.0030 (8) | 0.0045 (7) | 0.0067 (8) |
C6' | 0.0355 (11) | 0.0355 (12) | 0.0331 (10) | 0.0002 (9) | −0.0019 (8) | −0.0039 (9) |
C7 | 0.0464 (13) | 0.0481 (14) | 0.0418 (12) | −0.0235 (11) | 0.0107 (10) | −0.0079 (10) |
C7' | 0.0395 (11) | 0.0236 (10) | 0.0327 (10) | 0.0021 (8) | 0.0017 (8) | −0.0047 (8) |
C8 | 0.0251 (9) | 0.0385 (12) | 0.0297 (9) | −0.0050 (8) | 0.0057 (7) | −0.0050 (8) |
C9 | 0.0276 (10) | 0.0672 (17) | 0.0477 (13) | 0.0069 (11) | 0.0003 (9) | −0.0045 (12) |
C10 | 0.0641 (16) | 0.0617 (16) | 0.0368 (12) | −0.0238 (13) | 0.0219 (11) | −0.0168 (11) |
C11 | 0.0359 (11) | 0.0347 (12) | 0.0416 (11) | −0.0050 (9) | −0.0046 (9) | 0.0020 (9) |
O1 | 0.0272 (6) | 0.0225 (7) | 0.0322 (7) | 0.0011 (5) | 0.0083 (5) | 0.0012 (5) |
O2 | 0.0473 (9) | 0.0394 (9) | 0.0305 (7) | −0.0112 (7) | 0.0062 (6) | −0.0057 (6) |
O3 | 0.0309 (7) | 0.0380 (8) | 0.0450 (8) | −0.0052 (6) | 0.0079 (6) | 0.0068 (6) |
O4 | 0.0411 (8) | 0.0403 (8) | 0.0376 (8) | 0.0094 (7) | 0.0153 (6) | −0.0038 (6) |
S1 | 0.0277 (2) | 0.0285 (3) | 0.0323 (3) | 0.0020 (2) | 0.00963 (18) | 0.00179 (19) |
C1—C2 | 1.382 (2) | C6—H6 | 0.9500 |
C1—C6 | 1.388 (2) | C6'—C7' | 1.376 (3) |
C1—O1 | 1.428 (2) | C6'—H6' | 0.9500 |
C1'—C2' | 1.379 (3) | C7—C8 | 1.526 (3) |
C1'—C7' | 1.390 (3) | C7—H7A | 0.9800 |
C1'—S1 | 1.7486 (19) | C7—H7B | 0.9800 |
C2'—C3' | 1.386 (3) | C7—H7C | 0.9800 |
C2'—H2' | 0.9500 | C7'—H7' | 0.9500 |
C2—C3 | 1.400 (2) | C8—C9 | 1.527 (3) |
C2—C8 | 1.513 (2) | C8—H8 | 1.0000 |
C3'—C4' | 1.389 (3) | C9—H9A | 0.9800 |
C3'—H3' | 0.9500 | C9—H9B | 0.9800 |
C3—C4 | 1.380 (3) | C9—H9C | 0.9800 |
C3—H3 | 0.9500 | C10—O2 | 1.424 (3) |
C4—O2 | 1.369 (2) | C10—H10A | 0.9800 |
C4—C5 | 1.403 (3) | C10—H10B | 0.9800 |
C4'—C6' | 1.393 (3) | C10—H10C | 0.9800 |
C4'—C5' | 1.504 (3) | C11—H11A | 0.9800 |
C5—C6 | 1.381 (3) | C11—H11B | 0.9800 |
C5—C11 | 1.503 (3) | C11—H11C | 0.9800 |
C5'—H5'1 | 0.9800 | O1—S1 | 1.5967 (12) |
C5'—H5'2 | 0.9800 | O3—S1 | 1.4216 (14) |
C5'—H5'3 | 0.9800 | O4—S1 | 1.4221 (14) |
C2—C1—C6 | 122.74 (16) | C8—C7—H7B | 109.5 |
C2—C1—O1 | 118.38 (15) | H7A—C7—H7B | 109.5 |
C6—C1—O1 | 118.64 (15) | C8—C7—H7C | 109.5 |
C2'—C1'—C7' | 120.86 (18) | H7A—C7—H7C | 109.5 |
C2'—C1'—S1 | 120.13 (15) | H7B—C7—H7C | 109.5 |
C7'—C1'—S1 | 119.00 (14) | C6'—C7'—C1' | 119.26 (18) |
C1'—C2'—C3' | 118.97 (18) | C6'—C7'—H7' | 120.4 |
C1'—C2'—H2' | 120.5 | C1'—C7'—H7' | 120.4 |
C3'—C2'—H2' | 120.5 | C2—C8—C7 | 111.27 (16) |
C1—C2—C3 | 116.24 (16) | C2—C8—C9 | 110.51 (17) |
C1—C2—C8 | 123.71 (16) | C7—C8—C9 | 110.87 (17) |
C3—C2—C8 | 120.05 (16) | C2—C8—H8 | 108.0 |
C2'—C3'—C4' | 121.44 (18) | C7—C8—H8 | 108.0 |
C2'—C3'—H3' | 119.3 | C9—C8—H8 | 108.0 |
C4'—C3'—H3' | 119.3 | C8—C9—H9A | 109.5 |
C4—C3—C2 | 121.63 (17) | C8—C9—H9B | 109.5 |
C4—C3—H3 | 119.2 | H9A—C9—H9B | 109.5 |
C2—C3—H3 | 119.2 | C8—C9—H9C | 109.5 |
O2—C4—C3 | 123.76 (17) | H9A—C9—H9C | 109.5 |
O2—C4—C5 | 114.99 (16) | H9B—C9—H9C | 109.5 |
C3—C4—C5 | 121.26 (17) | O2—C10—H10A | 109.5 |
C3'—C4'—C6' | 118.20 (18) | O2—C10—H10B | 109.5 |
C3'—C4'—C5' | 121.55 (18) | H10A—C10—H10B | 109.5 |
C6'—C4'—C5' | 120.25 (18) | O2—C10—H10C | 109.5 |
C6—C5—C4 | 117.33 (16) | H10A—C10—H10C | 109.5 |
C6—C5—C11 | 121.84 (18) | H10B—C10—H10C | 109.5 |
C4—C5—C11 | 120.83 (18) | C5—C11—H11A | 109.5 |
C4'—C5'—H5'1 | 109.5 | C5—C11—H11B | 109.5 |
C4'—C5'—H5'2 | 109.5 | H11A—C11—H11B | 109.5 |
H5'1—C5'—H5'2 | 109.5 | C5—C11—H11C | 109.5 |
C4'—C5'—H5'3 | 109.5 | H11A—C11—H11C | 109.5 |
H5'1—C5'—H5'3 | 109.5 | H11B—C11—H11C | 109.5 |
H5'2—C5'—H5'3 | 109.5 | C1—O1—S1 | 120.71 (11) |
C5—C6—C1 | 120.79 (17) | C4—O2—C10 | 117.16 (15) |
C5—C6—H6 | 119.6 | O3—S1—O4 | 119.91 (9) |
C1—C6—H6 | 119.6 | O3—S1—O1 | 109.37 (8) |
C7'—C6'—C4' | 121.25 (18) | O4—S1—O1 | 102.77 (8) |
C7'—C6'—H6' | 119.4 | O3—S1—C1' | 109.08 (9) |
C4'—C6'—H6' | 119.4 | O4—S1—C1' | 109.79 (9) |
C8—C7—H7A | 109.5 | O1—S1—C1' | 104.76 (8) |
Cg1 and Cg2 are the centroids of the phenyl rings C1–C6 and C1'–C6', respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3′—H3′···O1i | 0.95 | 2.67 | 3.610 (2) | 169 |
C5′—H5′3···O3ii | 0.98 | 2.66 | 3.589 (3) | 159 |
C7—H7A···O4iii | 0.98 | 2.72 | 3.693 (3) | 175 |
C10—H10B···O3iv | 0.98 | 2.61 | 3.317 (3) | 130 |
C10—H10A···O4iii | 0.98 | 2.70 | 3.521 (3) | 142 |
C5′—H5′2···Cg2v | 0.98 | 2.84 | 3.706 | 148 |
C11—H11B···Cg1iv | 0.98 | 2.75 | 3.635 | 150 |
C9—H9A···Cg2 | 0.98 | 2.70 | 3.5373 | 144 |
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) x+1, y, z; (iii) x+1/2, −y+1/2, z−1/2; (iv) −x, −y, −z; (v) −x+1, −y, −z+1. |
2 | KAWDANa | TMPDTSb | |
C1'—S1 | 1.749 (2) | 1.748 | 1.732 |
S1—O1 | 1.597 (1) | 1.598 | 1.599 |
O1—C1 | 1.428 (2) | 1.425 | 1.428 |
C1'—S1—O1 | 104.76 (8) | 98.83 | 102.37 |
S1—O1—C1 | 120.71 (11) | 116.07 | 119.84 |
Dihedral angle | 29.97 (7) | 15.32 | 43.02 |
References: a Niestroj et al. (1998); b Wieczorek et al. (1975). |
Acknowledgements
The authors thank Cadi Ayyad University for financial support.
References
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