organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Absolute configuration of (2S)-4-(4-hy­dr­oxy­phen­yl)butan-2-ol

aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi 75270, Pakistan, bDepartment of Pharmacy, University of Peshawar, Peshawar 25120, Pakistan, and cX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 14 March 2011; accepted 17 March 2011; online 23 March 2011)

The title compound, C10H14O2, was isolated from the chloro­form extract of Taxus wallichiana Zucc. In the crystal, mol­ecules are linked by inter­molecular O—H⋯O hydrogen bonds, forming sheets parallel to (100). There are weak inter­molecular C—H⋯π inter­actions between the sheets.

Related literature

For the isolation of the title compound, see: Fan et al. (1999[Fan, C. Q., Yang, G. J., Zhao, W. M., Ding, B. Y. & Qin, Q. W. (1999). Chin. Chem. Lett. 10, 567-570.]). For the biological activity and medicinal uses of Taxus. wallichiana Zucc, see: Ahmed (1997[Ahmed, B. (1997). J. Hamdard Med. 20, 53-54.]); Baquar (1995[Baquar, S. R. (1995). Trees of Pakistan: Their Natural History Characteristics and Utilization, p. 634. Karachi: Royal Book Company.]); Kaul (1997[Kaul, M. K. (1997). Medicinal Plants of Kashmir and Ladakh: Temperate and Cold Arid Himalaya, p. 173. New Delhi, India: Indus Publishing Company.]); Nisar et al. (2008a[Nisar, M., Khan, I., Ali, I., Ahmad, W. & Choudhary, M. I. (2008a). J. Enz. Inhib. Med. Chem. 23, 256-260.],b[Nisar, M. Khan, I., Simjee, S. U., Gilani, A. H. Obaidullah, Perveen, H., (2008b). J. Ethnopharm. 116, 490-494.]; 2010[Nisar, M., Qayum, M., Adhikari, A., Khan, I., Kaleem, A. K., Ali, Z. & Choudhary, M. I. (2010). Nat. Prod. Commun. 5, 1727-1728.]); Prasain et al. (2001[Prasain, J. K., Stefanowicz, P., Kiyota, T., Habeichi, F. & Konishi, Y. (2001). Phytochemistry, 58, 1167-1170.]); Wani et al. (1971[Wani, M. C., Taylor, H. L., Wall, M. E., Coggon, P. & McPhail, A. T. (1971). J. Am. Chem. Soc. 93, 2325-2327.]).

[Scheme 1]

Experimental

Crystal data
  • C10H14O2

  • Mr = 166.21

  • Monoclinic, P 21

  • a = 7.2342 (2) Å

  • b = 6.3815 (2) Å

  • c = 9.9419 (4) Å

  • β = 92.216 (2)°

  • V = 458.63 (3) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 0.66 mm−1

  • T = 100 K

  • 0.39 × 0.12 × 0.05 mm

Data collection
  • Bruker SMART APEXII DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.784, Tmax = 0.966

  • 4954 measured reflections

  • 1455 independent reflections

  • 1446 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.075

  • S = 1.08

  • 1455 reflections

  • 165 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.24 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 579 Friedel pairs

  • Flack parameter: −0.03 (17)

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O1⋯O2i 0.92 (2) 1.72 (2) 2.6247 (13) 166 (2)
O2—H1O2⋯O1ii 0.91 (2) 1.88 (2) 2.7869 (13) 177.8 (19)
C8—H8ACg1iii 0.93 (2) 2.822 (15) 3.7033 (13) 158.1 (14)
Symmetry codes: (i) x, y, z-1; (ii) [-x+1, y+{\script{1\over 2}}, -z+1]; (iii) [-x, y+{\script{3\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXTL and PLATON.

Supporting information


Comment top

The genus Taxus belonging to the family Taxaceae is well known for its anticancer agents, namely taxol and dosetaxel (Wani et al., 1971; Prasain et al., 2001; Nisar et al., 2008a,b;2010). Taxus. wallichiana Zucc. (Himalayan Yew) is a small to medium sized evergreen tree, native to the northern areas of the Pakistan. Literature survey revealed that this plant is used traditionally for the treatment of high fever and acute painful conditions (Kaul, 1997). Leaves of the plant are used to make herbal tea for indigestion and epilepsy (Baquar, 1995; Ahmed, 1997). During our ongoing search on the medicinally important plants of Pakistan, the title compound was isolated from the chloroform-soluble part of Taxus. wallichiana and the structure was established on the basis of X-ray diffraction studies.

The molecular structure of the title compound is shown in Fig. 1. In the crystal structure, molecules are linked by intermolecular O1—H1O1···O2i and O2—H1O2···O1ii (see Table 1 for symmetry codes) hydrogen bonds to form two-dimensional sheets paralel to the (100) (Fig.2). A weak C—H···π interaction is also observed.

Related literature top

For the isolation of the title compound, see: Fan et al. (1999). For the biological activity and medicinal uses of Taxus. wallichiana Zucc, see: Ahmed (1997); Baquar (1995); Kaul (1997); Nisar et al. (2008a,b; 2010); Prasain et al. (2001); Wani et al. (1971).

Experimental top

Plant material: Taxus. wallichiana Zucc. was collected from the Hazara division of the North-western Frontier Province, Pakistan, in March 2005 and identified by Dr. Hasan Sher, a taxonomist of the Department of Botany, Jehanzeb Postgraduate College Saidu Sharif, Swat, Pakistan. A voucher specimen was deposited in the herbarium of the same institution. The aerial parts of the plant were air-dried under shade for six consecutive weeks at room temperature. The dried plant material was later on chopped, finely ground and stored in polyethylene bags under refrigeration for further experimentation.

The isolation of 4-(4'-hydroxyphenyl)-(2S)-butanol was previously carried out by Fan et al. (1999). Extraction and purification: The air-dried and powdered bark (4.0 K g) was macerated in methanol with occasional manual shaking at room temperature for a period of 72 h. The process was repeated 3 times followed by filtration. The combined filtrates were evaporated under reduced pressure at 313K to obtain a crude gummy material (514 g, 12.85% w/w), which was suspended in distilled water and successively extracted with hexane (11% w/w), chloroform (31.9% w/w), ethyl acetate (38.8% w/w), and finally with water (18.2% w/w) to give the respective fraction. The chloroform fraction (182 g) was further separated using silica gel column chromatography (95 mm in diameter). The column was eluted with increasing polarities of n-hexane with chloroform (1%-100%) followed by the gradient mixtures of chloroform and methanol. The methanol gradient was increased carefully to collect twenty seven sub-fractions (C1—C27). The sub-fraction C17 (611 mg) obtained on elution with 6% methanol/chloroform mixture was finally purified by flash column chromatography (silica gel, 8 g) by using chloroform: methanol; (95:5) as eluent to yield a colorless crystalline compound, 4-(4'-hydroxyphenyl)-(2S)-butanol (928 mg). Crystals suitable for X-ray diffraction were grown from a solution of the title compound in a mixture of chloroform: methanol (95:5).

Refinement top

The hydrogen atoms were located in difference Fourier maps and refined isotropically. The C—H distances refined in the range 0.94 (2)-1.02 (2)Å.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. Part of the crystal structure with O-H···O hydrogen bonds shown as dashed lines. Only H atoms involved in hydrogen bonds are included.
(2S)-4-(4-hydroxyphenyl)butan-2-ol top
Crystal data top
C10H14O2F(000) = 180
Mr = 166.21Dx = 1.204 Mg m3
Monoclinic, P21Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2ybCell parameters from 3477 reflections
a = 7.2342 (2) Åθ = 6.1–70.3°
b = 6.3815 (2) ŵ = 0.66 mm1
c = 9.9419 (4) ÅT = 100 K
β = 92.216 (2)°Block, colorles
V = 458.63 (3) Å30.39 × 0.12 × 0.05 mm
Z = 2
Data collection top
Bruker SMART APEXII DUO CCD area-detector
diffractometer
1455 independent reflections
Radiation source: fine-focus sealed tube1446 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ϕ and ω scansθmax = 67.5°, θmin = 6.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 88
Tmin = 0.784, Tmax = 0.966k = 77
4954 measured reflectionsl = 1110
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.029H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075 w = 1/[σ2(Fo2) + (0.0499P)2 + 0.0461P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
1455 reflectionsΔρmax = 0.19 e Å3
165 parametersΔρmin = 0.24 e Å3
1 restraintAbsolute structure: Flack (1983), 579 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.03 (17)
Crystal data top
C10H14O2V = 458.63 (3) Å3
Mr = 166.21Z = 2
Monoclinic, P21Cu Kα radiation
a = 7.2342 (2) ŵ = 0.66 mm1
b = 6.3815 (2) ÅT = 100 K
c = 9.9419 (4) Å0.39 × 0.12 × 0.05 mm
β = 92.216 (2)°
Data collection top
Bruker SMART APEXII DUO CCD area-detector
diffractometer
1455 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1446 reflections with I > 2σ(I)
Tmin = 0.784, Tmax = 0.966Rint = 0.028
4954 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.029H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075Δρmax = 0.19 e Å3
S = 1.08Δρmin = 0.24 e Å3
1455 reflectionsAbsolute structure: Flack (1983), 579 Friedel pairs
165 parametersAbsolute structure parameter: 0.03 (17)
1 restraint
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.33418 (12)0.03888 (15)0.11761 (9)0.0200 (2)
O20.33463 (12)0.33901 (17)0.93717 (9)0.0214 (2)
C10.22229 (17)0.3267 (2)0.42530 (13)0.0191 (3)
C20.25737 (17)0.2886 (2)0.29010 (14)0.0184 (3)
C30.29911 (15)0.08712 (19)0.24875 (13)0.0161 (3)
C40.30875 (17)0.0757 (2)0.34234 (14)0.0191 (3)
C50.27631 (16)0.0347 (2)0.47664 (13)0.0187 (3)
C60.23165 (16)0.1659 (2)0.52052 (13)0.0173 (3)
C70.19572 (19)0.2007 (2)0.66828 (14)0.0222 (3)
C80.20129 (16)0.4288 (2)0.71453 (13)0.0179 (3)
C90.18659 (17)0.4510 (2)0.86638 (13)0.0202 (3)
C100.1875 (2)0.6786 (3)0.91038 (16)0.0286 (4)
H10.192 (2)0.463 (3)0.4534 (16)0.019 (4)*
H20.245 (2)0.401 (3)0.2254 (19)0.026 (4)*
H40.339 (2)0.216 (3)0.3145 (17)0.024 (4)*
H50.281 (2)0.143 (3)0.5411 (18)0.025 (4)*
H7A0.076 (2)0.136 (3)0.6896 (18)0.027 (4)*
H7B0.293 (3)0.123 (3)0.720 (2)0.032 (5)*
H8A0.103 (3)0.501 (3)0.6728 (18)0.026 (4)*
H8B0.322 (2)0.494 (3)0.6865 (15)0.013 (4)*
H90.078 (2)0.383 (3)0.8913 (17)0.020 (4)*
H10A0.075 (3)0.755 (4)0.873 (2)0.044 (6)*
H10B0.304 (2)0.749 (3)0.8792 (17)0.021 (4)*
H10C0.183 (3)0.691 (3)1.011 (2)0.040 (5)*
H1O10.319 (3)0.151 (4)0.062 (2)0.043 (6)*
H1O20.444 (3)0.400 (3)0.920 (2)0.036 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0240 (4)0.0247 (5)0.0115 (5)0.0004 (4)0.0046 (3)0.0002 (4)
O20.0213 (5)0.0303 (5)0.0125 (5)0.0034 (4)0.0007 (3)0.0033 (4)
C10.0245 (6)0.0192 (7)0.0135 (6)0.0005 (5)0.0016 (5)0.0021 (5)
C20.0220 (6)0.0222 (8)0.0110 (6)0.0008 (5)0.0003 (5)0.0023 (5)
C30.0138 (6)0.0244 (7)0.0101 (6)0.0007 (5)0.0023 (4)0.0021 (5)
C40.0188 (6)0.0195 (7)0.0193 (7)0.0006 (5)0.0038 (4)0.0005 (5)
C50.0201 (6)0.0218 (7)0.0142 (7)0.0017 (5)0.0018 (4)0.0029 (5)
C60.0180 (6)0.0223 (7)0.0115 (7)0.0027 (5)0.0003 (5)0.0003 (5)
C70.0304 (7)0.0262 (8)0.0102 (7)0.0047 (6)0.0024 (5)0.0003 (5)
C80.0172 (6)0.0247 (7)0.0119 (6)0.0009 (5)0.0004 (4)0.0005 (5)
C90.0161 (6)0.0325 (8)0.0123 (7)0.0010 (5)0.0024 (4)0.0019 (6)
C100.0278 (7)0.0378 (9)0.0201 (8)0.0062 (7)0.0012 (5)0.0108 (6)
Geometric parameters (Å, º) top
O1—C31.3728 (15)C5—H50.94 (2)
O1—H1O10.91 (3)C6—C71.5180 (17)
O2—C91.4473 (16)C7—C81.5265 (19)
O2—H1O20.90 (2)C7—H7A0.988 (19)
C1—C61.3959 (19)C7—H7B0.99 (2)
C1—C21.3988 (18)C8—C91.5241 (17)
C1—H10.943 (19)C8—H8A0.93 (2)
C2—C31.3865 (18)C8—H8B1.018 (15)
C2—H20.96 (2)C9—C101.517 (2)
C3—C41.3948 (18)C9—H90.938 (17)
C4—C51.390 (2)C10—H10A1.01 (2)
C4—H40.97 (2)C10—H10B1.013 (18)
C5—C61.3942 (19)C10—H10C1.01 (2)
C3—O1—H1O1112.1 (15)C8—C7—H7A110.2 (11)
C9—O2—H1O2109.6 (13)C6—C7—H7B106.5 (12)
C6—C1—C2121.21 (12)C8—C7—H7B108.1 (12)
C6—C1—H1118.9 (10)H7A—C7—H7B107.0 (15)
C2—C1—H1119.9 (10)C9—C8—C7112.65 (11)
C3—C2—C1119.72 (12)C9—C8—H8A108.3 (11)
C3—C2—H2120.5 (11)C7—C8—H8A109.0 (12)
C1—C2—H2119.7 (11)C9—C8—H8B109.0 (9)
O1—C3—C2122.67 (11)C7—C8—H8B108.8 (9)
O1—C3—C4117.40 (11)H8A—C8—H8B109.0 (14)
C2—C3—C4119.93 (11)O2—C9—C10109.73 (11)
C5—C4—C3119.64 (12)O2—C9—C8110.92 (10)
C5—C4—H4119.9 (11)C10—C9—C8112.02 (12)
C3—C4—H4120.4 (11)O2—C9—H9104.8 (11)
C4—C5—C6121.57 (12)C10—C9—H9111.0 (11)
C4—C5—H5120.8 (12)C8—C9—H9108.0 (10)
C6—C5—H5117.6 (12)C9—C10—H10A111.3 (13)
C5—C6—C1117.92 (12)C9—C10—H10B109.5 (11)
C5—C6—C7119.18 (11)H10A—C10—H10B109.7 (16)
C1—C6—C7122.90 (12)C9—C10—H10C111.3 (13)
C6—C7—C8115.31 (11)H10A—C10—H10C105.7 (17)
C6—C7—H7A109.3 (11)H10B—C10—H10C109.3 (15)
C6—C1—C2—C31.14 (18)C2—C1—C6—C50.29 (18)
C1—C2—C3—O1179.72 (10)C2—C1—C6—C7179.64 (11)
C1—C2—C3—C40.99 (17)C5—C6—C7—C8163.67 (11)
O1—C3—C4—C5179.33 (10)C1—C6—C7—C816.26 (18)
C2—C3—C4—C50.01 (17)C6—C7—C8—C9173.32 (10)
C3—C4—C5—C60.86 (17)C7—C8—C9—O258.43 (14)
C4—C5—C6—C10.71 (17)C7—C8—C9—C10178.58 (11)
C4—C5—C6—C7179.36 (11)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring
D—H···AD—HH···AD···AD—H···A
O1—H1O1···O2i0.92 (2)1.72 (2)2.6247 (13)166 (2)
O2—H1O2···O1ii0.91 (2)1.88 (2)2.7869 (13)177.8 (19)
C8—H8A···Cg1iii0.93 (2)2.822 (15)3.7033 (13)158.1 (14)
Symmetry codes: (i) x, y, z1; (ii) x+1, y+1/2, z+1; (iii) x, y+3/2, z+1.

Experimental details

Crystal data
Chemical formulaC10H14O2
Mr166.21
Crystal system, space groupMonoclinic, P21
Temperature (K)100
a, b, c (Å)7.2342 (2), 6.3815 (2), 9.9419 (4)
β (°) 92.216 (2)
V3)458.63 (3)
Z2
Radiation typeCu Kα
µ (mm1)0.66
Crystal size (mm)0.39 × 0.12 × 0.05
Data collection
DiffractometerBruker SMART APEXII DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.784, 0.966
No. of measured, independent and
observed [I > 2σ(I)] reflections
4954, 1455, 1446
Rint0.028
(sin θ/λ)max1)0.599
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.075, 1.08
No. of reflections1455
No. of parameters165
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.19, 0.24
Absolute structureFlack (1983), 579 Friedel pairs
Absolute structure parameter0.03 (17)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C1–C6 ring
D—H···AD—HH···AD···AD—H···A
O1—H1O1···O2i0.92 (2)1.72 (2)2.6247 (13)166 (2)
O2—H1O2···O1ii0.91 (2)1.88 (2)2.7869 (13)177.8 (19)
C8—H8A···Cg1iii0.93 (2)2.822 (15)3.7033 (13)158.1 (14)
Symmetry codes: (i) x, y, z1; (ii) x+1, y+1/2, z+1; (iii) x, y+3/2, z+1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

SY thanks the School of Physics, Universiti Sains Malaysia, for providing X-ray diffraction research facilities. HKF thanks the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160.

References

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