8β-Eth-oxy-eremophil-3,7(11)-diene-8α,12;6α,15-diolide.

The title compound, C17H20O5, an eremophilane sesquiternoid, was isolated from the roots of Ligularia lapathifolia. The mol-ecule contains four fused rings of which the six-membered ring A adopts a half-chair conformation, the six-membered ring B adopts a chair conformation, the five-membered ring C is almost planar (r.m.s. deviation = 0.015 Å) and the five-membered ring D adopts an envelope conformation with the quaternary C atom as the flap. The methyl and the eth-oxy groups adopt a syn conformation and the A/B ring junction is cis-fused. No directional inter-molecular inter-actions could be identified in the crystal.

Related literature

For further information on the isolation of the title compound, see Fei et al. (2007 ▶). For pucking paramaters, see: Cremer & Pople (1975 ▶); Boeyens (1978 ▶)

Experimental

Crystal data

C17H20O5

M = 304.33

Orthorhombic,

a = 8.4925 (2) Å

b = 13.0302 (4) Å

c = 14.1381 (9) Å

V = 1564.50 (12) Å3

Z = 4

Cu Kα radiation

μ = 0.78 mm−1

T = 294 K

0.33 × 0.28 × 0.12 mm

Data collection

Agilent SuperNova (Dual, Cu at zero, Eos) diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013 ▶) T min = 0.743, T max = 1.000

14336 measured reflections

2994 independent reflections

2871 reflections with I > 2σ(I)

R int = 0.027

Refinement

R[F 2 > 2σ(F 2)] = 0.037

wR(F 2) = 0.103

S = 1.03

2994 reflections

202 parameters

H-atom parameters constrained

Δρmax = 0.13 e Å−3

Δρmin = −0.18 e Å−3

Absolute structure: Flack (1983 ▶)

Flack parameter: −0.1 (2)

Data collection: CrysAlis PRO (Agilent, 2013 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶); software used to prepare material for publication: OLEX2.

Crystal structure: contains datablock(s) global. DOI: 10.1107/S1600536813015729/hb7083sup1.cif

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C17H20O5	Dx = 1.292 Mg m−3
Mr = 304.33	Cu Kα radiation, λ = 1.5418 Å
Orthorhombic, P212121	Cell parameters from 9242 reflections
a = 8.4925 (2) Å	θ = 4.6–70.7°
b = 13.0302 (4) Å	µ = 0.78 mm−1
c = 14.1381 (9) Å	T = 294 K
V = 1564.50 (12) Å3	Block, colourless
Z = 4	0.33 × 0.28 × 0.12 mm
F(000) = 648

Agilent SuperNova (Dual, Cu at zero, Eos) diffractometer	2994 independent reflections
Radiation source: SuperNova (Cu) X-ray Source	2871 reflections with I > 2σ(I)
Mirror monochromator	Rint = 0.027
Detector resolution: 16.0733 pixels mm-1	θmax = 70.8°, θmin = 4.6°
ω scans	h = −10→9
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2013)	k = −15→15
Tmin = 0.743, Tmax = 1.000	l = −16→17
14336 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)] = 0.037	H-atom parameters constrained
wR(F2) = 0.103	w = 1/[σ2(Fo2) + (0.0636P)2 + 0.1574P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max = 0.003
2994 reflections	Δρmax = 0.13 e Å−3
202 parameters	Δρmin = −0.18 e Å−3
0 restraints	Absolute structure: Flack (1983), 000 Friedel pairs
Primary atom site location: iterative	Flack parameter: −0.1 (2)

Experimental. CrysAlisPro, Agilent Technologies, Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET) (compiled Feb 1 2013,16:14:44) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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	0.9183 (2)	0.64050 (12)	0.11330 (10)	0.0794 (4)
O2	0.79269 (15)	0.60175 (8)	0.24732 (9)	0.0556 (3)
O3	0.82873 (14)	0.24550 (10)	0.20230 (9)	0.0580 (3)
O4	0.6780 (2)	0.17448 (13)	0.09057 (11)	0.0839 (5)
O5	0.81102 (14)	0.52062 (10)	0.39285 (7)	0.0514 (3)
C1	0.3694 (2)	0.36787 (16)	0.35509 (16)	0.0642 (5)
H1A	0.3487	0.3085	0.3945	0.077*
H1B	0.3133	0.4257	0.3822	0.077*
C2	0.3051 (2)	0.34733 (16)	0.25617 (17)	0.0678 (5)
H2A	0.2071	0.3096	0.2617	0.081*
H2B	0.2818	0.4124	0.2260	0.081*
C3	0.4146 (2)	0.28847 (14)	0.19487 (14)	0.0582 (4)
H3	0.3795	0.2650	0.1365	0.070*
C4	0.5619 (2)	0.26851 (12)	0.22151 (12)	0.0484 (4)
C5	0.63488 (19)	0.29910 (12)	0.31377 (12)	0.0467 (4)
C6	0.80727 (18)	0.31837 (12)	0.27873 (11)	0.0457 (4)
H6	0.8817	0.3034	0.3299	0.055*
C7	0.83272 (17)	0.42502 (11)	0.24365 (11)	0.0416 (3)
C8	0.75684 (19)	0.50977 (12)	0.30066 (11)	0.0436 (3)
C9	0.58186 (19)	0.49238 (12)	0.30652 (12)	0.0460 (4)
H9A	0.5376	0.4907	0.2433	0.055*
H9B	0.5331	0.5486	0.3407	0.055*
C10	0.5468 (2)	0.39090 (12)	0.35713 (12)	0.0481 (4)
H10	0.5794	0.3977	0.4233	0.058*
C11	0.89795 (19)	0.46356 (14)	0.16573 (11)	0.0485 (4)
C12	0.8750 (2)	0.57663 (15)	0.16860 (12)	0.0551 (4)
C13	0.9784 (2)	0.4157 (2)	0.08268 (13)	0.0680 (5)
H13A	1.0069	0.3463	0.0978	0.102*
H13B	1.0715	0.4541	0.0676	0.102*
H13C	0.9085	0.4159	0.0293	0.102*
C14	0.6368 (3)	0.20772 (17)	0.38296 (16)	0.0726 (6)
H14A	0.6874	0.2279	0.4408	0.109*
H14B	0.6935	0.1516	0.3551	0.109*
H14C	0.5307	0.1867	0.3961	0.109*
C15	0.6863 (2)	0.22373 (14)	0.16241 (14)	0.0575 (4)
C16	0.9771 (2)	0.5300 (2)	0.40545 (14)	0.0762 (7)
H16A	1.0163	0.5873	0.3686	0.091*
H16B	1.0290	0.4681	0.3835	0.091*
C17	1.0122 (3)	0.5461 (3)	0.50483 (17)	0.0970 (9)
H17A	1.1237	0.5406	0.5148	0.146*
H17B	0.9588	0.4953	0.5420	0.146*
H17C	0.9773	0.6133	0.5234	0.146*

	U11	U22	U33	U12	U13	U23
O1	0.0966 (11)	0.0798 (10)	0.0619 (8)	−0.0179 (9)	0.0110 (8)	0.0133 (8)
O2	0.0652 (7)	0.0444 (6)	0.0572 (7)	−0.0037 (5)	0.0106 (6)	−0.0012 (5)
O3	0.0483 (6)	0.0539 (6)	0.0718 (7)	0.0118 (5)	−0.0004 (6)	−0.0224 (6)
O4	0.0807 (10)	0.0882 (11)	0.0828 (10)	−0.0103 (9)	0.0044 (8)	−0.0454 (9)
O5	0.0490 (6)	0.0629 (7)	0.0422 (6)	−0.0064 (5)	0.0061 (5)	−0.0128 (5)
C1	0.0469 (9)	0.0657 (12)	0.0800 (13)	−0.0003 (9)	0.0186 (9)	0.0034 (10)
C2	0.0406 (8)	0.0616 (10)	0.1014 (15)	−0.0028 (8)	0.0023 (10)	0.0036 (11)
C3	0.0480 (9)	0.0559 (9)	0.0707 (11)	−0.0084 (7)	−0.0062 (8)	−0.0015 (9)
C4	0.0457 (8)	0.0414 (8)	0.0580 (9)	−0.0049 (6)	−0.0002 (7)	−0.0044 (7)
C5	0.0457 (8)	0.0435 (8)	0.0510 (9)	0.0038 (6)	0.0009 (7)	0.0012 (7)
C6	0.0404 (7)	0.0469 (8)	0.0497 (8)	0.0094 (6)	−0.0042 (7)	−0.0087 (7)
C7	0.0349 (7)	0.0486 (8)	0.0412 (7)	0.0026 (6)	−0.0023 (6)	−0.0095 (6)
C8	0.0452 (8)	0.0428 (8)	0.0427 (8)	−0.0009 (6)	0.0051 (6)	−0.0042 (6)
C9	0.0431 (8)	0.0442 (8)	0.0508 (8)	0.0066 (6)	0.0069 (7)	−0.0044 (7)
C10	0.0462 (8)	0.0507 (9)	0.0474 (8)	0.0020 (7)	0.0096 (7)	−0.0004 (7)
C11	0.0405 (8)	0.0662 (10)	0.0387 (8)	0.0000 (7)	0.0016 (6)	−0.0077 (7)
C12	0.0544 (10)	0.0647 (10)	0.0462 (9)	−0.0088 (8)	0.0015 (7)	0.0037 (8)
C13	0.0609 (11)	0.0976 (15)	0.0454 (9)	0.0077 (11)	0.0106 (8)	−0.0129 (10)
C14	0.0833 (14)	0.0608 (12)	0.0738 (12)	0.0049 (10)	0.0043 (11)	0.0214 (10)
C15	0.0575 (10)	0.0494 (9)	0.0655 (10)	−0.0025 (8)	−0.0012 (9)	−0.0146 (8)
C16	0.0539 (11)	0.1208 (19)	0.0537 (11)	−0.0224 (12)	0.0009 (9)	−0.0185 (12)
C17	0.0844 (17)	0.147 (3)	0.0600 (13)	−0.0186 (16)	−0.0166 (11)	−0.0009 (15)

O1—C12	1.200 (2)	C6—C7	1.491 (2)
O2—C8	1.4484 (19)	C7—C8	1.511 (2)
O2—C12	1.354 (2)	C7—C11	1.331 (2)
O3—C6	1.4501 (18)	C8—C9	1.506 (2)
O3—C15	1.364 (2)	C9—H9A	0.9700
O4—C15	1.204 (2)	C9—H9B	0.9700
O5—C8	1.3894 (19)	C9—C10	1.533 (2)
O5—C16	1.427 (2)	C10—H10	0.9800
C1—H1A	0.9700	C11—C12	1.487 (3)
C1—H1B	0.9700	C11—C13	1.495 (2)
C1—C2	1.525 (3)	C13—H13A	0.9600
C1—C10	1.536 (2)	C13—H13B	0.9600
C2—H2A	0.9700	C13—H13C	0.9600
C2—H2B	0.9700	C14—H14A	0.9600
C2—C3	1.485 (3)	C14—H14B	0.9600
C3—H3	0.9300	C14—H14C	0.9600
C3—C4	1.332 (3)	C16—H16A	0.9700
C4—C5	1.498 (2)	C16—H16B	0.9700
C4—C15	1.468 (3)	C16—C17	1.452 (3)
C5—C6	1.566 (2)	C17—H17A	0.9600
C5—C10	1.538 (2)	C17—H17B	0.9600
C5—C14	1.541 (2)	C17—H17C	0.9600
C6—H6	0.9800
C12—O2—C8	109.65 (12)	C8—C9—C10	110.33 (13)
C15—O3—C6	109.44 (12)	H9A—C9—H9B	108.1
C8—O5—C16	116.95 (13)	C10—C9—H9A	109.6
H1A—C1—H1B	107.7	C10—C9—H9B	109.6
C2—C1—H1A	108.8	C1—C10—C5	108.51 (14)
C2—C1—H1B	108.8	C1—C10—H10	108.2
C2—C1—C10	113.74 (15)	C5—C10—H10	108.2
C10—C1—H1A	108.8	C9—C10—C1	110.51 (14)
C10—C1—H1B	108.8	C9—C10—C5	112.97 (13)
C1—C2—H2A	108.8	C9—C10—H10	108.2
C1—C2—H2B	108.8	C7—C11—C12	107.26 (14)
H2A—C2—H2B	107.7	C7—C11—C13	133.06 (18)
C3—C2—C1	113.69 (16)	C12—C11—C13	119.65 (17)
C3—C2—H2A	108.8	O1—C12—O2	121.74 (18)
C3—C2—H2B	108.8	O1—C12—C11	129.02 (18)
C2—C3—H3	119.2	O2—C12—C11	109.25 (14)
C4—C3—C2	121.60 (18)	C11—C13—H13A	109.5
C4—C3—H3	119.2	C11—C13—H13B	109.5
C3—C4—C5	125.64 (16)	C11—C13—H13C	109.5
C3—C4—C15	126.34 (18)	H13A—C13—H13B	109.5
C15—C4—C5	107.69 (15)	H13A—C13—H13C	109.5
C4—C5—C6	98.85 (13)	H13B—C13—H13C	109.5
C4—C5—C10	110.65 (14)	C5—C14—H14A	109.5
C4—C5—C14	110.58 (15)	C5—C14—H14B	109.5
C10—C5—C6	117.14 (13)	C5—C14—H14C	109.5
C10—C5—C14	110.67 (15)	H14A—C14—H14B	109.5
C14—C5—C6	108.35 (14)	H14A—C14—H14C	109.5
O3—C6—C5	104.38 (13)	H14B—C14—H14C	109.5
O3—C6—H6	109.7	O3—C15—C4	108.67 (14)
O3—C6—C7	110.13 (12)	O4—C15—O3	120.78 (18)
C5—C6—H6	109.7	O4—C15—C4	130.56 (19)
C7—C6—C5	112.97 (12)	O5—C16—H16A	109.7
C7—C6—H6	109.7	O5—C16—H16B	109.7
C6—C7—C8	116.21 (13)	O5—C16—C17	109.64 (19)
C11—C7—C6	133.40 (14)	H16A—C16—H16B	108.2
C11—C7—C8	110.06 (14)	C17—C16—H16A	109.7
O2—C8—C7	103.73 (12)	C17—C16—H16B	109.7
O2—C8—C9	111.14 (14)	C16—C17—H17A	109.5
O5—C8—O2	109.54 (13)	C16—C17—H17B	109.5
O5—C8—C7	115.69 (14)	C16—C17—H17C	109.5
O5—C8—C9	106.89 (13)	H17A—C17—H17B	109.5
C9—C8—C7	109.89 (13)	H17A—C17—H17C	109.5
C8—C9—H9A	109.6	H17B—C17—H17C	109.5
C8—C9—H9B	109.6
O2—C8—C9—C10	176.04 (12)	C7—C11—C12—O1	178.38 (19)
O3—C6—C7—C8	157.37 (13)	C7—C11—C12—O2	−1.6 (2)
O3—C6—C7—C11	−15.2 (2)	C8—O2—C12—O1	−179.84 (17)
O5—C8—C9—C10	−64.47 (16)	C8—O2—C12—C11	0.15 (19)
C1—C2—C3—C4	−8.3 (3)	C8—O5—C16—C17	176.9 (2)
C2—C1—C10—C5	−58.3 (2)	C8—C7—C11—C12	2.34 (18)
C2—C1—C10—C9	66.0 (2)	C8—C7—C11—C13	−175.70 (18)
C2—C3—C4—C5	1.3 (3)	C8—C9—C10—C1	−174.70 (14)
C2—C3—C4—C15	−171.17 (17)	C8—C9—C10—C5	−52.92 (19)
C3—C4—C5—C6	−146.24 (17)	C10—C1—C2—C3	37.6 (2)
C3—C4—C5—C10	−22.7 (2)	C10—C5—C6—O3	−151.01 (14)
C3—C4—C5—C14	100.3 (2)	C10—C5—C6—C7	−31.4 (2)
C3—C4—C15—O3	160.45 (17)	C11—C7—C8—O2	−2.24 (17)
C3—C4—C15—O4	−20.1 (3)	C11—C7—C8—O5	−122.21 (15)
C4—C5—C6—O3	−32.27 (14)	C11—C7—C8—C9	116.66 (15)
C4—C5—C6—C7	87.37 (15)	C12—O2—C8—O5	125.24 (14)
C4—C5—C10—C1	48.68 (18)	C12—O2—C8—C7	1.17 (17)
C4—C5—C10—C9	−74.22 (17)	C12—O2—C8—C9	−116.86 (15)
C5—C4—C15—O3	−13.11 (19)	C13—C11—C12—O1	−3.3 (3)
C5—C4—C15—O4	166.4 (2)	C13—C11—C12—O2	176.75 (15)
C5—C6—C7—C8	41.10 (18)	C14—C5—C6—O3	82.97 (16)
C5—C6—C7—C11	−131.49 (18)	C14—C5—C6—C7	−157.39 (14)
C6—O3—C15—O4	171.11 (18)	C14—C5—C10—C1	−74.25 (19)
C6—O3—C15—C4	−9.36 (19)	C14—C5—C10—C9	162.84 (15)
C6—C5—C10—C1	160.89 (15)	C15—O3—C6—C5	26.98 (17)
C6—C5—C10—C9	38.0 (2)	C15—O3—C6—C7	−94.55 (16)
C6—C7—C8—O2	−176.51 (13)	C15—C4—C5—C6	27.38 (16)
C6—C7—C8—O5	63.51 (18)	C15—C4—C5—C10	150.88 (14)
C6—C7—C8—C9	−57.62 (18)	C15—C4—C5—C14	−86.13 (17)
C6—C7—C11—C12	175.26 (16)	C16—O5—C8—O2	−64.2 (2)
C6—C7—C11—C13	−2.8 (3)	C16—O5—C8—C7	52.5 (2)
C7—C8—C9—C10	61.80 (17)	C16—O5—C8—C9	175.24 (17)