A guaianolide-type sesquiterpene lactone

The title compound, 3α-hydr­oxy-11αH-guaia-4(15),10(14)-dien-12,6α-olide, C₁₅H₂₀O₃, is a 5,7,5-tricyclic guaianol­ide. The hydr­oxy group is equatorial and the methyl group is axial. Three rings, viz. a five-membered, a seven-membered and a γ-lactone ring, are cis- and trans-fused to each other, and adopt half-chair, chair and envelope conformations, respectively. The crystal structure is stabilized by inter­molecular O—H...O hydrogen bonds between the hydr­oxy group and the γ-lactone carbonyl O atom along the b direction.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.040
• wR factor = 0.085
• Data-to-parameter ratio = 10.0

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT035_ALERT_1_A No _chemical_absolute_configuration info given .          ?

Author Response: The absolute structure of this organic compound without heavy-atom cannot be determined in this experimental conditions.

Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C10    -   C14     ..       7.58 su

Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O1     -   C6      ..       6.52 su

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           26.90
           From the CIF: _reflns_number_total               1661
           Count of symmetry unique reflns         1661
           Completeness (_total/calc)            100.00%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no

   1 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   1 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 1994); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

3α-hydroxy-11αH-guaia-4(15),10 (14)-diene-12,6α-olide

Crystal data

C15H20O3	Dx = 1.246 Mg m^−3
Mr = 248.31	Melting point: 396 K
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P2ac2ab	Cell parameters from 26 reflections
a = 8.346 (1) Å	θ = 3.5–13.2°
b = 9.951 (1) Å	µ = 0.09 mm^−1
c = 15.934 (2) Å	T = 291 K
V = 1323.3 (3) Å^3	Block, colourless
Z = 4	0.56 × 0.50 × 0.44 mm
F(000) = 536

Data collection

Siemens P4 diffractometer	Rint = 0.007
Radiation source: normal-focus sealed tube	θmax = 26.9°, θmin = 2.4°
Graphite monochromator	h = 0→10
ω scans	k = 0→12
1828 measured reflections	l = −1→20
1661 independent reflections	3 standard reflections every 97 reflections
1152 reflections with I > 2σ(I)	intensity decay: 3.1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.040	H-atom parameters constrained
wR(F^2) = 0.085	w = 1/[σ^2(Fo^2) + (0.0413P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.98	(Δ/σ)max < 0.001
1661 reflections	Δρmax = 0.15 e Å^−3
166 parameters	Δρmin = −0.11 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.032 (2)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.3089 (2)	0.55842 (15)	0.48841 (9)	0.0499 (5)
O2	0.2486 (3)	1.07485 (16)	0.44163 (14)	0.0880 (8)
H2O	0.2745	1.1489	0.4597	0.106*
O3	0.3227 (3)	0.34313 (17)	0.45475 (13)	0.0864 (7)
C1	0.4242 (3)	0.8716 (2)	0.61554 (14)	0.0427 (6)
H1	0.5368	0.8708	0.6329	0.051*
C2	0.3922 (3)	1.0087 (2)	0.57369 (16)	0.0495 (6)
H2A	0.3477	1.0720	0.6137	0.059*
H2B	0.4901	1.0459	0.5505	0.059*
C3	0.2722 (3)	0.9771 (2)	0.50451 (15)	0.0477 (7)
H3	0.1684	0.9580	0.5307	0.057*
C4	0.3373 (3)	0.8482 (2)	0.46931 (14)	0.0368 (5)
C5	0.4069 (3)	0.7679 (2)	0.54191 (12)	0.0360 (5)
H5	0.5149	0.7392	0.5257	0.043*
C6	0.3110 (3)	0.6427 (2)	0.56326 (13)	0.0362 (5)
H6	0.2011	0.6684	0.5777	0.043*
C7	0.3784 (3)	0.5522 (2)	0.63202 (14)	0.0446 (6)
H7	0.4955	0.5596	0.6304	0.053*
C8	0.3240 (4)	0.5901 (3)	0.71976 (14)	0.0616 (8)
H8A	0.3621	0.5228	0.7591	0.074*
H8B	0.2078	0.5896	0.7216	0.074*
C9	0.3845 (4)	0.7284 (3)	0.74756 (14)	0.0689 (9)
H9A	0.3501	0.7447	0.8048	0.083*
H9B	0.5007	0.7282	0.7470	0.083*
C10	0.3251 (4)	0.8416 (3)	0.69242 (15)	0.0517 (7)
C11	0.3334 (3)	0.4107 (2)	0.60192 (15)	0.0492 (7)
H11	0.4197	0.3477	0.6158	0.059*
C12	0.3234 (4)	0.4279 (2)	0.50852 (16)	0.0531 (7)
C13	0.1732 (4)	0.3559 (3)	0.63433 (18)	0.0694 (8)
H13A	0.1458	0.2757	0.6040	0.083*
H13B	0.0910	0.4221	0.6263	0.083*
H13C	0.1824	0.3354	0.6930	0.083*
C14	0.1969 (4)	0.9104 (3)	0.71342 (18)	0.0774 (9)
H14A	0.1631	0.9818	0.6802	0.093*
H14B	0.1400	0.8878	0.7616	0.093*
C15	0.3452 (3)	0.8184 (2)	0.38959 (15)	0.0502 (7)
H15A	0.3089	0.8795	0.3497	0.060*
H15B	0.3873	0.7362	0.3727	0.060*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0756 (12)	0.0294 (7)	0.0447 (10)	−0.0051 (9)	−0.0085 (10)	0.0006 (7)
O2	0.148 (2)	0.0318 (9)	0.0845 (14)	−0.0012 (12)	−0.0492 (15)	0.0048 (11)
O3	0.147 (2)	0.0375 (9)	0.0752 (12)	−0.0106 (13)	−0.0080 (16)	−0.0117 (11)
C1	0.0409 (13)	0.0437 (13)	0.0435 (13)	−0.0035 (12)	−0.0065 (12)	−0.0067 (11)
C2	0.0533 (15)	0.0382 (12)	0.0568 (15)	−0.0050 (12)	−0.0019 (14)	−0.0081 (13)
C3	0.0593 (16)	0.0316 (12)	0.0524 (16)	0.0011 (11)	−0.0112 (13)	0.0005 (12)
C4	0.0353 (13)	0.0316 (10)	0.0436 (13)	−0.0053 (12)	−0.0012 (11)	0.0005 (10)
C5	0.0337 (13)	0.0346 (11)	0.0397 (12)	−0.0008 (11)	0.0008 (10)	−0.0010 (11)
C6	0.0399 (12)	0.0362 (11)	0.0326 (11)	0.0015 (11)	−0.0026 (11)	−0.0038 (10)
C7	0.0431 (14)	0.0457 (12)	0.0449 (14)	0.0011 (11)	−0.0078 (12)	0.0072 (12)
C8	0.0805 (19)	0.0636 (17)	0.0406 (14)	−0.0027 (18)	−0.0054 (16)	0.0110 (13)
C9	0.094 (2)	0.078 (2)	0.0349 (13)	−0.0086 (19)	−0.0055 (15)	−0.0006 (15)
C10	0.0607 (17)	0.0539 (14)	0.0405 (13)	−0.0025 (16)	−0.0003 (14)	−0.0179 (13)
C11	0.0486 (15)	0.0381 (13)	0.0609 (16)	0.0028 (12)	−0.0043 (14)	0.0123 (12)
C12	0.0636 (17)	0.0350 (13)	0.0607 (16)	−0.0062 (13)	−0.0046 (16)	0.0004 (13)
C13	0.0688 (19)	0.0543 (15)	0.085 (2)	−0.0067 (16)	0.0041 (18)	0.0184 (16)
C14	0.088 (2)	0.078 (2)	0.0664 (19)	−0.006 (2)	0.0236 (19)	−0.0196 (17)
C15	0.0628 (17)	0.0425 (14)	0.0454 (13)	0.0017 (13)	−0.0006 (13)	0.0050 (12)

Geometric parameters (Å, º)

O1—C12	1.343 (3)	C7—C8	1.517 (3)
O1—C6	1.458 (2)	C7—C11	1.534 (3)
O2—C3	1.410 (3)	C7—H7	0.9800
O2—H2O	0.8200	C8—C9	1.532 (4)
O3—C12	1.203 (3)	C8—H8A	0.9700
C1—C10	1.508 (3)	C8—H8B	0.9700
C1—C2	1.542 (3)	C9—C10	1.512 (3)
C1—C5	1.569 (3)	C9—H9A	0.9700
C1—H1	0.9800	C9—H9B	0.9700
C2—C3	1.522 (3)	C10—C14	1.314 (4)
C2—H2A	0.9700	C11—C12	1.500 (3)
C2—H2B	0.9700	C11—C13	1.534 (4)
C3—C4	1.502 (3)	C11—H11	0.9800
C3—H3	0.9800	C13—H13A	0.9600
C4—C15	1.306 (3)	C13—H13B	0.9600
C4—C5	1.521 (3)	C13—H13C	0.9600
C5—C6	1.520 (3)	C14—H14A	0.9300
C5—H5	0.9800	C14—H14B	0.9300
C6—C7	1.525 (3)	C15—H15A	0.9300
C6—H6	0.9800	C15—H15B	0.9300
C12—O1—C6	111.07 (17)	C6—C7—H7	107.7
C3—O2—H2O	109.5	C11—C7—H7	107.7
C10—C1—C2	115.6 (2)	C7—C8—C9	113.0 (2)
C10—C1—C5	115.29 (19)	C7—C8—H8A	109.0
C2—C1—C5	104.03 (17)	C9—C8—H8A	109.0
C10—C1—H1	107.1	C7—C8—H8B	109.0
C2—C1—H1	107.1	C9—C8—H8B	109.0
C5—C1—H1	107.1	H8A—C8—H8B	107.8
C3—C2—C1	104.16 (19)	C10—C9—C8	113.2 (2)
C3—C2—H2A	110.9	C10—C9—H9A	108.9
C1—C2—H2A	110.9	C8—C9—H9A	108.9
C3—C2—H2B	110.9	C10—C9—H9B	108.9
C1—C2—H2B	110.9	C8—C9—H9B	108.9
H2A—C2—H2B	108.9	H9A—C9—H9B	107.8
O2—C3—C4	111.99 (19)	C14—C10—C1	123.4 (3)
O2—C3—C2	117.7 (2)	C14—C10—C9	120.5 (3)
C4—C3—C2	102.0 (2)	C1—C10—C9	116.1 (2)
O2—C3—H3	108.2	C12—C11—C7	102.65 (19)
C4—C3—H3	108.2	C12—C11—C13	109.0 (2)
C2—C3—H3	108.2	C7—C11—C13	115.8 (2)
C15—C4—C3	125.1 (2)	C12—C11—H11	109.7
C15—C4—C5	126.9 (2)	C7—C11—H11	109.7
C3—C4—C5	107.63 (17)	C13—C11—H11	109.7
C6—C5—C4	113.56 (18)	O3—C12—O1	120.5 (2)
C6—C5—C1	114.85 (17)	O3—C12—C11	128.8 (2)
C4—C5—C1	104.98 (16)	O1—C12—C11	110.6 (2)
C6—C5—H5	107.7	C11—C13—H13A	109.5
C4—C5—H5	107.7	C11—C13—H13B	109.5
C1—C5—H5	107.7	H13A—C13—H13B	109.5
O1—C6—C5	107.14 (16)	C11—C13—H13C	109.5
O1—C6—C7	104.65 (16)	H13A—C13—H13C	109.5
C5—C6—C7	116.8 (2)	H13B—C13—H13C	109.5
O1—C6—H6	109.3	C10—C14—H14A	120.0
C5—C6—H6	109.3	C10—C14—H14B	120.0
C7—C6—H6	109.3	H14A—C14—H14B	120.0
C8—C7—C6	113.9 (2)	C4—C15—H15A	120.0
C8—C7—C11	116.3 (2)	C4—C15—H15B	120.0
C6—C7—C11	103.11 (17)	H15A—C15—H15B	120.0
C8—C7—H7	107.7
C10—C1—C2—C3	−95.3 (2)	C5—C6—C7—C8	88.4 (3)
C5—C1—C2—C3	32.1 (2)	O1—C6—C7—C11	−26.4 (2)
C1—C2—C3—O2	−164.7 (2)	C5—C6—C7—C11	−144.7 (2)
C1—C2—C3—C4	−41.7 (2)	C6—C7—C8—C9	−64.7 (3)
O2—C3—C4—C15	−11.6 (4)	C11—C7—C8—C9	175.6 (2)
C2—C3—C4—C15	−138.3 (3)	C7—C8—C9—C10	61.3 (3)
O2—C3—C4—C5	162.4 (2)	C2—C1—C10—C14	14.3 (3)
C2—C3—C4—C5	35.7 (2)	C5—C1—C10—C14	−107.2 (3)
C15—C4—C5—C6	−75.6 (3)	C2—C1—C10—C9	−163.7 (2)
C3—C4—C5—C6	110.5 (2)	C5—C1—C10—C9	74.8 (3)
C15—C4—C5—C1	158.1 (3)	C8—C9—C10—C14	95.4 (3)
C3—C4—C5—C1	−15.8 (2)	C8—C9—C10—C1	−86.6 (3)
C10—C1—C5—C6	−8.1 (3)	C8—C7—C11—C12	151.9 (2)
C2—C1—C5—C6	−135.6 (2)	C6—C7—C11—C12	26.5 (3)
C10—C1—C5—C4	117.4 (2)	C8—C7—C11—C13	33.3 (3)
C2—C1—C5—C4	−10.2 (2)	C6—C7—C11—C13	−92.1 (2)
C12—O1—C6—C5	141.0 (2)	C6—O1—C12—O3	179.4 (3)
C12—O1—C6—C7	16.4 (3)	C6—O1—C12—C11	1.2 (3)
C4—C5—C6—O1	59.7 (2)	C7—C11—C12—O3	164.0 (3)
C1—C5—C6—O1	−179.51 (18)	C13—C11—C12—O3	−72.8 (4)
C4—C5—C6—C7	176.53 (19)	C7—C11—C12—O1	−18.1 (3)
C1—C5—C6—C7	−62.6 (3)	C13—C11—C12—O1	105.2 (3)
O1—C6—C7—C8	−153.3 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O3^i	0.82	1.98	2.748 (2)	157

Symmetry code: (i) x, y+1, z.