organic compounds
3-(4-Chlorophenyl)-1-[(2R,4aR,8aR)-4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen-2-yl]prop-2-en-1-one
aLaboratoire de Chimie Bioorganique et Analytique, URAC 22 BP 146, FSTM, Université Hassan II, Mohammedia-Casablanca 20810 Mohammedia, Morocco, bLaboratoire de Chimie Biomoleculaire, Substances Naturelles et Réactivité, URAC16, Université Cadi Ayyad, Faculté des Sciences Semlalia, BP 2390, Bd My Abdellah, 40000 Marrakech, Morocco, and cUniversité Blaise Pascal, Laboratoire des Matériaux Inorganiques, UMR CNRS 6002, 24 Avenue des Landais, 63177 Aubière, France
*Correspondence e-mail: mtebbaa@yahoo.com
The title compound, C21H25ClO, was semi-synthesized from isocostic acid, isolated from the aerial part of Inula Viscosa (L) Aiton [or Dittrichia Viscosa (L) Greuter]. The cyclohexene ring has a half-chair conformation, whereas the cyclohexane ring displays a chair conformation.
Related literature
For background to the medicinal interest in Inula Viscosa (L) Aiton [or Dittrichia Viscosa (L) Greuter], see: Shtacher & Kasshman (1970); Bohlman & Gupta (1982); Azoulay et al. (1986); Bohlman et al. (1977); Ceccherelli et al. (1988). For the synthesis, see: Kutney & Singh (1984). For see: Cremer & Pople (1975).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2005); cell SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536811016886/ci5186sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811016886/ci5186Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536811016886/ci5186Isup3.cml
p-Chlorobenzaldehyde dissolved in ethanol (20 ml) was added drop by drop to a mixture of 1-(4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen- 2-yl)ethanone (1 g, 4.84 mmol), anhydrous ethanol (40 ml), and 2 ml of a solution of sodium hydroxide (2 N, 667 mg, 4.84 mmol). The mixture was stirred for 3 h at room temperature. After neutralization, it was extracted three times with 40 ml of dichloromethane, the organic phase was dried over sodium sulfate and then evaporated under vacuum. The residue was subjected to
on a column of silica gel with hexane-ethyl acetate (97:4) as to obtain 3-(4-chlorphenyl)-1-(4a, 8-dimethyl-1,2,3,4,4a,5,6,8a- octahydronaphthalen-2-yl)prop-2-en-1-one with a yield of 90%. The title compound was recrystallized in hexane-ethyl acetate (7:3).All H atoms were positioned geometrically and treated as riding with C-H = 0.93 Å (aromatic), 0.96 Å (methyl), 0.97 Å (methylene), 0.98Å (methine) with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(Cmethyl).
Data collection: APEX2 (Bruker, 2005); cell
SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).C21H25ClO | F(000) = 352 |
Mr = 328.86 | Dx = 1.206 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 3362 reflections |
a = 10.9869 (5) Å | θ = 3.5–26.3° |
b = 7.0054 (3) Å | µ = 0.21 mm−1 |
c = 12.1883 (6) Å | T = 298 K |
β = 105.726 (2)° | Prism, colourless |
V = 902.99 (7) Å3 | 0.28 × 0.20 × 0.16 mm |
Z = 2 |
Bruker X8 APEX CCD area-detector diffractometer | 2713 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.021 |
Graphite monochromator | θmax = 26.3°, θmin = 4.1° |
Detector resolution: 8.3333 pixels mm-1 | h = −13→13 |
ω and ϕ scans | k = −7→8 |
6963 measured reflections | l = −15→14 |
3358 independent 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)] = 0.039 | H-atom parameters constrained |
wR(F2) = 0.106 | w = 1/[σ2(Fo2) + (0.0579P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max = 0.001 |
3358 reflections | Δρmax = 0.18 e Å−3 |
210 parameters | Δρmin = −0.21 e Å−3 |
1 restraint | Absolute structure: Flack (1983), 1373 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.11 (7) |
C21H25ClO | V = 902.99 (7) Å3 |
Mr = 328.86 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 10.9869 (5) Å | µ = 0.21 mm−1 |
b = 7.0054 (3) Å | T = 298 K |
c = 12.1883 (6) Å | 0.28 × 0.20 × 0.16 mm |
β = 105.726 (2)° |
Bruker X8 APEX CCD area-detector diffractometer | 2713 reflections with I > 2σ(I) |
6963 measured reflections | Rint = 0.021 |
3358 independent reflections |
R[F2 > 2σ(F2)] = 0.039 | H-atom parameters constrained |
wR(F2) = 0.106 | Δρmax = 0.18 e Å−3 |
S = 1.08 | Δρmin = −0.21 e Å−3 |
3358 reflections | Absolute structure: Flack (1983), 1373 Friedel pairs |
210 parameters | Absolute structure parameter: −0.11 (7) |
1 restraint |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
C1 | −0.12078 (19) | 0.1716 (3) | 0.28143 (17) | 0.0460 (5) | |
H1A | −0.1945 | 0.2468 | 0.2826 | 0.055* | |
H1B | −0.0877 | 0.1149 | 0.3562 | 0.055* | |
C2 | −0.02074 (18) | 0.3009 (3) | 0.25507 (16) | 0.0436 (5) | |
H2 | 0.0531 | 0.2209 | 0.2575 | 0.052* | |
C3 | −0.06528 (19) | 0.3826 (3) | 0.13502 (16) | 0.0481 (5) | |
H3A | 0.0022 | 0.4573 | 0.1189 | 0.058* | |
H3B | −0.1368 | 0.4666 | 0.1299 | 0.058* | |
C4 | −0.1039 (2) | 0.2228 (3) | 0.04658 (17) | 0.0508 (5) | |
H4A | −0.0302 | 0.1463 | 0.0471 | 0.061* | |
H4B | −0.1347 | 0.2790 | −0.0286 | 0.061* | |
C4A | −0.20679 (16) | 0.0933 (3) | 0.06975 (15) | 0.0413 (4) | |
C5 | −0.2281 (2) | −0.0790 (3) | −0.01062 (18) | 0.0519 (5) | |
H5A | −0.2520 | −0.0344 | −0.0889 | 0.062* | |
H5B | −0.1495 | −0.1495 | 0.0015 | 0.062* | |
C6 | −0.3304 (2) | −0.2119 (3) | 0.00779 (19) | 0.0600 (6) | |
H6A | −0.4126 | −0.1619 | −0.0326 | 0.072* | |
H6B | −0.3210 | −0.3363 | −0.0239 | 0.072* | |
C7 | −0.3245 (2) | −0.2335 (3) | 0.13080 (19) | 0.0555 (6) | |
H7 | −0.3772 | −0.3241 | 0.1498 | 0.067* | |
C8 | −0.25005 (18) | −0.1339 (3) | 0.21527 (17) | 0.0466 (5) | |
C8A | −0.15912 (16) | 0.0137 (3) | 0.19227 (16) | 0.0407 (4) | |
H8A | −0.0811 | −0.0559 | 0.1945 | 0.049* | |
C9 | 0.02262 (19) | 0.4566 (3) | 0.34237 (17) | 0.0480 (5) | |
C10 | 0.12607 (19) | 0.5813 (3) | 0.32607 (18) | 0.0526 (5) | |
H10 | 0.1705 | 0.5438 | 0.2747 | 0.063* | |
C11 | 0.1570 (2) | 0.7435 (3) | 0.38210 (17) | 0.0502 (5) | |
H11 | 0.1146 | 0.7733 | 0.4363 | 0.060* | |
C12 | 0.25209 (19) | 0.8815 (3) | 0.36696 (17) | 0.0458 (5) | |
C13 | 0.3308 (2) | 0.8509 (4) | 0.2960 (2) | 0.0618 (6) | |
H13 | 0.3262 | 0.7353 | 0.2575 | 0.074* | |
C14 | 0.4147 (2) | 0.9871 (4) | 0.2817 (2) | 0.0669 (7) | |
H14 | 0.4662 | 0.9643 | 0.2338 | 0.080* | |
C15 | 0.4221 (2) | 1.1572 (3) | 0.33870 (19) | 0.0570 (6) | |
C16 | 0.3477 (2) | 1.1907 (3) | 0.4105 (2) | 0.0597 (6) | |
H16 | 0.3543 | 1.3056 | 0.4499 | 0.072* | |
C17 | 0.2636 (2) | 1.0548 (3) | 0.42400 (18) | 0.0540 (5) | |
H17 | 0.2131 | 1.0790 | 0.4725 | 0.065* | |
C18 | −0.2510 (2) | −0.1670 (4) | 0.33701 (18) | 0.0668 (6) | |
H18A | −0.3116 | −0.2645 | 0.3397 | 0.100* | |
H18B | −0.2736 | −0.0508 | 0.3684 | 0.100* | |
H18C | −0.1685 | −0.2069 | 0.3807 | 0.100* | |
C19 | −0.3293 (2) | 0.2045 (3) | 0.05233 (19) | 0.0544 (5) | |
H19A | −0.3572 | 0.2478 | −0.0252 | 0.082* | |
H19B | −0.3155 | 0.3124 | 0.1027 | 0.082* | |
H19C | −0.3928 | 0.1234 | 0.0685 | 0.082* | |
O | −0.02456 (15) | 0.4817 (2) | 0.42008 (13) | 0.0666 (5) | |
Cl1 | 0.52589 (7) | 1.33272 (12) | 0.31822 (6) | 0.0916 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0503 (11) | 0.0493 (11) | 0.0398 (10) | −0.0030 (9) | 0.0149 (9) | 0.0080 (9) |
C2 | 0.0450 (10) | 0.0452 (12) | 0.0426 (10) | −0.0024 (8) | 0.0150 (9) | −0.0013 (9) |
C3 | 0.0563 (12) | 0.0474 (12) | 0.0456 (11) | −0.0116 (9) | 0.0222 (9) | 0.0044 (9) |
C4 | 0.0547 (12) | 0.0623 (14) | 0.0407 (11) | −0.0130 (10) | 0.0217 (10) | −0.0005 (10) |
C4A | 0.0398 (9) | 0.0441 (10) | 0.0415 (10) | −0.0028 (8) | 0.0135 (8) | 0.0041 (9) |
C5 | 0.0533 (12) | 0.0609 (13) | 0.0450 (11) | −0.0084 (10) | 0.0191 (9) | −0.0081 (10) |
C6 | 0.0604 (13) | 0.0575 (14) | 0.0615 (14) | −0.0153 (11) | 0.0156 (11) | −0.0047 (11) |
C7 | 0.0553 (13) | 0.0488 (12) | 0.0659 (14) | −0.0105 (10) | 0.0223 (11) | 0.0054 (11) |
C8 | 0.0482 (11) | 0.0431 (11) | 0.0505 (11) | 0.0023 (9) | 0.0169 (9) | 0.0100 (9) |
C8A | 0.0385 (9) | 0.0427 (11) | 0.0416 (10) | 0.0035 (8) | 0.0122 (8) | 0.0063 (8) |
C9 | 0.0547 (12) | 0.0482 (11) | 0.0429 (11) | −0.0026 (9) | 0.0163 (9) | 0.0002 (9) |
C10 | 0.0555 (12) | 0.0524 (12) | 0.0526 (12) | −0.0058 (10) | 0.0193 (10) | −0.0099 (10) |
C11 | 0.0567 (12) | 0.0539 (13) | 0.0418 (11) | 0.0009 (10) | 0.0163 (10) | −0.0046 (10) |
C12 | 0.0492 (11) | 0.0479 (12) | 0.0399 (10) | −0.0019 (9) | 0.0113 (9) | −0.0046 (9) |
C13 | 0.0684 (14) | 0.0576 (13) | 0.0655 (14) | −0.0105 (12) | 0.0286 (12) | −0.0241 (12) |
C14 | 0.0655 (14) | 0.0746 (16) | 0.0695 (15) | −0.0161 (13) | 0.0337 (12) | −0.0237 (14) |
C15 | 0.0542 (12) | 0.0655 (14) | 0.0520 (13) | −0.0140 (11) | 0.0157 (10) | −0.0074 (11) |
C16 | 0.0713 (15) | 0.0500 (13) | 0.0571 (13) | −0.0074 (11) | 0.0160 (12) | −0.0165 (11) |
C17 | 0.0615 (13) | 0.0556 (13) | 0.0493 (12) | −0.0027 (11) | 0.0225 (10) | −0.0105 (10) |
C18 | 0.0787 (16) | 0.0653 (14) | 0.0586 (13) | −0.0192 (13) | 0.0222 (12) | 0.0195 (13) |
C19 | 0.0495 (12) | 0.0541 (13) | 0.0560 (13) | 0.0075 (10) | 0.0083 (10) | 0.0123 (10) |
O | 0.0877 (11) | 0.0676 (10) | 0.0527 (9) | −0.0183 (9) | 0.0331 (8) | −0.0118 (8) |
Cl1 | 0.0968 (5) | 0.0864 (5) | 0.0996 (5) | −0.0428 (4) | 0.0405 (4) | −0.0190 (4) |
C1—C2 | 1.524 (2) | C8—C8A | 1.516 (3) |
C1—C8A | 1.527 (3) | C8A—H8A | 0.98 |
C1—H1A | 0.97 | C9—O | 1.209 (2) |
C1—H1B | 0.97 | C9—C10 | 1.489 (3) |
C2—C9 | 1.508 (3) | C10—C11 | 1.322 (3) |
C2—C3 | 1.523 (3) | C10—H10 | 0.93 |
C2—H2 | 0.98 | C11—C12 | 1.471 (3) |
C3—C4 | 1.532 (3) | C11—H11 | 0.93 |
C3—H3A | 0.97 | C12—C17 | 1.388 (3) |
C3—H3B | 0.97 | C12—C13 | 1.395 (3) |
C4—C4A | 1.534 (2) | C13—C14 | 1.370 (3) |
C4—H4A | 0.97 | C13—H13 | 0.93 |
C4—H4B | 0.97 | C14—C15 | 1.371 (3) |
C4A—C19 | 1.520 (3) | C14—H14 | 0.93 |
C4A—C5 | 1.532 (3) | C15—C16 | 1.370 (3) |
C4A—C8A | 1.546 (2) | C15—Cl1 | 1.740 (2) |
C5—C6 | 1.522 (3) | C16—C17 | 1.367 (3) |
C5—H5A | 0.97 | C16—H16 | 0.93 |
C5—H5B | 0.97 | C17—H17 | 0.93 |
C6—C7 | 1.491 (3) | C18—H18A | 0.96 |
C6—H6A | 0.97 | C18—H18B | 0.96 |
C6—H6B | 0.97 | C18—H18C | 0.96 |
C7—C8 | 1.326 (3) | C19—H19A | 0.96 |
C7—H7 | 0.93 | C19—H19B | 0.96 |
C8—C18 | 1.505 (3) | C19—H19C | 0.96 |
C2—C1—C8A | 110.86 (15) | C18—C8—C8A | 117.95 (18) |
C2—C1—H1A | 109.5 | C8—C8A—C1 | 115.52 (16) |
C8A—C1—H1A | 109.5 | C8—C8A—C4A | 110.91 (15) |
C2—C1—H1B | 109.5 | C1—C8A—C4A | 112.44 (15) |
C8A—C1—H1B | 109.5 | C8—C8A—H8A | 105.7 |
H1A—C1—H1B | 108.1 | C1—C8A—H8A | 105.7 |
C9—C2—C3 | 111.35 (16) | C4A—C8A—H8A | 105.7 |
C9—C2—C1 | 112.90 (16) | O—C9—C10 | 121.57 (19) |
C3—C2—C1 | 111.31 (15) | O—C9—C2 | 122.51 (18) |
C9—C2—H2 | 107.0 | C10—C9—C2 | 115.91 (18) |
C3—C2—H2 | 107.0 | C11—C10—C9 | 122.3 (2) |
C1—C2—H2 | 107.0 | C11—C10—H10 | 118.8 |
C2—C3—C4 | 110.94 (16) | C9—C10—H10 | 118.8 |
C2—C3—H3A | 109.5 | C10—C11—C12 | 126.3 (2) |
C4—C3—H3A | 109.5 | C10—C11—H11 | 116.8 |
C2—C3—H3B | 109.5 | C12—C11—H11 | 116.8 |
C4—C3—H3B | 109.5 | C17—C12—C13 | 117.22 (19) |
H3A—C3—H3B | 108.0 | C17—C12—C11 | 118.91 (19) |
C3—C4—C4A | 112.32 (15) | C13—C12—C11 | 123.86 (18) |
C3—C4—H4A | 109.1 | C14—C13—C12 | 121.5 (2) |
C4A—C4—H4A | 109.1 | C14—C13—H13 | 119.2 |
C3—C4—H4B | 109.1 | C12—C13—H13 | 119.2 |
C4A—C4—H4B | 109.1 | C13—C14—C15 | 119.4 (2) |
H4A—C4—H4B | 107.9 | C13—C14—H14 | 120.3 |
C19—C4A—C5 | 109.79 (16) | C15—C14—H14 | 120.3 |
C19—C4A—C4 | 109.90 (17) | C16—C15—C14 | 120.6 (2) |
C5—C4A—C4 | 109.92 (15) | C16—C15—Cl1 | 119.90 (18) |
C19—C4A—C8A | 112.03 (15) | C14—C15—Cl1 | 119.51 (18) |
C5—C4A—C8A | 106.63 (16) | C17—C16—C15 | 119.8 (2) |
C4—C4A—C8A | 108.51 (15) | C17—C16—H16 | 120.1 |
C6—C5—C4A | 112.23 (16) | C15—C16—H16 | 120.1 |
C6—C5—H5A | 109.2 | C16—C17—C12 | 121.4 (2) |
C4A—C5—H5A | 109.2 | C16—C17—H17 | 119.3 |
C6—C5—H5B | 109.2 | C12—C17—H17 | 119.3 |
C4A—C5—H5B | 109.2 | C8—C18—H18A | 109.5 |
H5A—C5—H5B | 107.9 | C8—C18—H18B | 109.5 |
C7—C6—C5 | 112.20 (18) | H18A—C18—H18B | 109.5 |
C7—C6—H6A | 109.2 | C8—C18—H18C | 109.5 |
C5—C6—H6A | 109.2 | H18A—C18—H18C | 109.5 |
C7—C6—H6B | 109.2 | H18B—C18—H18C | 109.5 |
C5—C6—H6B | 109.2 | C4A—C19—H19A | 109.5 |
H6A—C6—H6B | 107.9 | C4A—C19—H19B | 109.5 |
C8—C7—C6 | 125.22 (19) | H19A—C19—H19B | 109.5 |
C8—C7—H7 | 117.4 | C4A—C19—H19C | 109.5 |
C6—C7—H7 | 117.4 | H19A—C19—H19C | 109.5 |
C7—C8—C18 | 121.11 (19) | H19B—C19—H19C | 109.5 |
C7—C8—C8A | 120.92 (18) |
Experimental details
Crystal data | |
Chemical formula | C21H25ClO |
Mr | 328.86 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 298 |
a, b, c (Å) | 10.9869 (5), 7.0054 (3), 12.1883 (6) |
β (°) | 105.726 (2) |
V (Å3) | 902.99 (7) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.21 |
Crystal size (mm) | 0.28 × 0.20 × 0.16 |
Data collection | |
Diffractometer | Bruker X8 APEX CCD area-detector diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6963, 3358, 2713 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.624 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.039, 0.106, 1.08 |
No. of reflections | 3358 |
No. of parameters | 210 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.18, −0.21 |
Absolute structure | Flack (1983), 1373 Friedel pairs |
Absolute structure parameter | −0.11 (7) |
Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
Acknowledgements
We thank the National Center of Scientific and Technological Research (CNRST) which supports our scientific research.
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Isocostic acid is the main constituent of the dichloromethane extract of the aerial part of Inula viscosa (L) Aiton or Dittrichia Viscosa (L) Greuter. This plant is widespread in Mediterranean area and extends to the Atlantic cost of Morocco. It is a well known medicinal plant (Shtacher & Kasshman, 1970; Bohlman & Gupta, 1982) and has some pharmacological activities (Azoulay et al., 1986). This plant has undergone a chemical study in order to isolate sesquiterpene lactones (Bohlman et al., 1977) and sesquiterpene acids (Ceccherelli et al., 1988). The literature does not report any article on the transformation of this acid. In order to prepare products with high added value, we studied the reactivity of this acid. Thus, from this acid, we have prepared by reaction of Curtius the 1-(4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen-2-yl)-ethanone which was synthesized by Kutney et al.(1984). The condensation of this sesquiterpene ketone with p-chlorbenzaldehyde in the presence of sodium hydroxide allows us to obtain the 3-(4-chlorophenyl)-1-(4a,8-dimethyl- 1,2,3,4,4a,5,6, 8a-octahydro-naphthalen-2-yl)prop-2-en-1-one with a good yield of 90%. The structure of this new derivative of isocostic acid was established by NMR spectral analysis of 1H, 13 C and mass spectroscopy and confirmed by its single-crystal X-ray structure.
In the title molecule (Fig. 1), the cyclohexane ring adopts a chair conformation, as indicated by the total puckering amplitude Q(T) = 0.574 (2) Å and spherical polar angle θ = 180.0 (2)° with ϕ = 48 (13)°. The cyclohexene ring has a half-chair conformation with QT = 0.525 (2) Å, θ =129.8 (2)°, ϕ = 191.1 (3)° (Cremer & Pople, 1975). Owing to the presence of Cl atom, the absolute configuration could be fully confirmed, by refining the Flack (1983) parameter as C2(R), C4a(R) and C8a(R).