A neo-clerodane diterpene from Teucrium tomentosum

A neo-clerodane diterpene, 15-hydroxy-15,16-epoxy-6α-neo-cleroda-3,13(16),14-triene-18,19:20,12-diolide, C₂₀H₂₂O₆, showing antifeedant activity against lepidopterous pests, has been isolated from Teucrium tomentosum and characterized by NMR and X-ray crystallographic methods. The crystallographic studies reveal that the cyclo­hexene and cyclo­hexane rings adopt a half-chair and a chair conformation, respectively. The furan ring exhibits rotational disorder. The mol­ecules in the crystal structure are stabilized by a network of O—H...O and C—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.041
• wR factor = 0.111
• Data-to-parameter ratio = 8.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.91 Ratio
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors ....        O16
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors ....        C16
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....        C13

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           27.99
           From the CIF: _reflns_number_total               2103
           Count of symmetry unique reflns         2214
           Completeness (_total/calc)             94.99%
           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

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 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

---

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97 and PARST97 (Nardelli, 1995).

15-hydroxy-15,16-epoxy-6α-neo-cleroda-3,13 (16),14-triene-18,19:20,12-diolide

Crystal data

C20H22O6	F(000) = 380
Mr = 358.38	Dx = 1.372 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2673 reflections
a = 7.7363 (7) Å	θ = 2.7–27.7°
b = 9.5260 (8) Å	µ = 0.10 mm^−1
c = 11.8422 (10) Å	T = 293 K
β = 96.134 (2)°	Rectangular block, colourless
V = 867.73 (13) Å^3	0.30 × 0.24 × 0.15 mm
Z = 2

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2103 independent reflections
Radiation source: fine-focus sealed tube	1912 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.019
ω scans	θmax = 28.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→9
Tmin = 0.979, Tmax = 0.982	k = −7→12
5505 measured reflections	l = −15→13

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.111	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0732P)^2 + 0.0489P] where P = (Fo^2 + 2Fc^2)/3
2103 reflections	(Δ/σ)max < 0.001
236 parameters	Δρmax = 0.19 e Å^−3
1 restraint	Δρmin = −0.18 e Å^−3

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
O6	0.2555 (2)	0.3475 (2)	1.01843 (13)	0.0625 (5)
H6	0.3164	0.4095	0.9955	0.094*
O12	−0.0631 (2)	0.2746 (2)	0.50289 (12)	0.0567 (5)
O16	−0.5834 (4)	0.3747 (4)	0.3408 (2)	0.1151 (12)
O17	0.1576 (2)	0.3767 (2)	0.60478 (15)	0.0631 (5)
O19	0.4890 (2)	0.2090 (3)	0.88318 (17)	0.0684 (6)
O20	0.5337 (3)	0.0663 (3)	1.0329 (2)	0.0923 (9)
C1	0.0344 (3)	0.0162 (2)	0.71487 (18)	0.0452 (5)
H1A	0.1337	0.0203	0.6714	0.054*
H1B	−0.0683	−0.0045	0.6631	0.054*
C2	0.0620 (4)	−0.0986 (3)	0.8057 (2)	0.0574 (6)
H2A	−0.0436	−0.1108	0.8420	0.069*
H2B	0.0881	−0.1868	0.7704	0.069*
C3	0.2081 (4)	−0.0600 (3)	0.8929 (2)	0.0597 (7)
H3	0.2665	−0.1307	0.9355	0.072*
C4	0.2570 (3)	0.0721 (3)	0.91137 (19)	0.0530 (6)
C5	0.1794 (3)	0.1990 (3)	0.84974 (17)	0.0419 (5)
C6	0.1222 (3)	0.3118 (3)	0.93181 (17)	0.0474 (5)
H6A	0.0265	0.2717	0.9692	0.057*
C7	0.0508 (3)	0.4373 (3)	0.8654 (2)	0.0511 (5)
H7A	0.1425	0.4775	0.8258	0.061*
H7B	0.0167	0.5074	0.9181	0.061*
C8	−0.1052 (3)	0.4052 (3)	0.7788 (2)	0.0498 (5)
H8	−0.2016	0.3810	0.8225	0.060*
C9	−0.0783 (2)	0.2769 (2)	0.70147 (16)	0.0386 (4)
C10	0.0121 (3)	0.1565 (2)	0.77365 (16)	0.0382 (4)
H10	−0.0705	0.1349	0.8285	0.046*
C11	−0.2541 (3)	0.2287 (3)	0.64169 (16)	0.0443 (5)
H11A	−0.2923	0.1435	0.6764	0.053*
H11B	−0.3416	0.3008	0.6468	0.053*
C12	−0.2259 (3)	0.2022 (3)	0.51780 (17)	0.0471 (5)
H12	−0.2103	0.1013	0.5065	0.057*
C13	−0.3647 (3)	0.2547 (3)	0.43137 (19)	0.0541 (6)
C14	−0.3922 (4)	0.2128 (4)	0.3161 (2)	0.0662 (8)
H14	−0.3298	0.1445	0.2817	0.079*
C15	−0.5212 (4)	0.2876 (5)	0.2663 (2)	0.0791 (10)
H15	−0.5634	0.2809	0.1899	0.095*
C16	−0.4845 (6)	0.3523 (6)	0.4427 (3)	0.1112 (17)
H16	−0.4992	0.3989	0.5100	0.133*
C17	0.0216 (3)	0.3163 (3)	0.60214 (18)	0.0464 (5)
C18	−0.1596 (5)	0.5378 (3)	0.7124 (3)	0.0804 (10)
H18A	−0.2575	0.5174	0.6581	0.121*
H18B	−0.0646	0.5705	0.6735	0.121*
H18C	−0.1910	0.6090	0.7638	0.121*
C19	0.3445 (3)	0.2474 (3)	0.79817 (19)	0.0518 (6)
H19A	0.3548	0.2001	0.7267	0.062*
H19B	0.3420	0.3480	0.7852	0.062*
C20	0.4364 (4)	0.1107 (4)	0.9546 (2)	0.0649 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O6	0.0617 (10)	0.0779 (14)	0.0435 (8)	−0.0052 (10)	−0.0146 (8)	−0.0106 (8)
O12	0.0481 (8)	0.0827 (13)	0.0389 (7)	0.0016 (9)	0.0024 (7)	0.0068 (9)
O16	0.108 (2)	0.138 (3)	0.0882 (16)	0.051 (2)	−0.0394 (16)	0.0063 (18)
O17	0.0484 (9)	0.0757 (13)	0.0645 (10)	−0.0121 (9)	0.0033 (8)	0.0193 (10)
O19	0.0386 (8)	0.0938 (15)	0.0697 (11)	0.0059 (9)	−0.0088 (7)	−0.0046 (12)
O20	0.0807 (15)	0.109 (2)	0.0777 (15)	0.0342 (15)	−0.0348 (12)	−0.0034 (14)
C1	0.0534 (12)	0.0401 (11)	0.0415 (10)	0.0011 (9)	0.0024 (9)	−0.0010 (9)
C2	0.0694 (15)	0.0429 (13)	0.0597 (13)	0.0017 (12)	0.0062 (12)	0.0056 (11)
C3	0.0707 (16)	0.0537 (15)	0.0534 (13)	0.0154 (13)	−0.0003 (12)	0.0124 (12)
C4	0.0555 (13)	0.0592 (15)	0.0423 (11)	0.0138 (11)	−0.0041 (9)	0.0044 (10)
C5	0.0398 (9)	0.0478 (12)	0.0370 (9)	0.0050 (9)	−0.0013 (8)	0.0004 (9)
C6	0.0442 (10)	0.0587 (14)	0.0380 (9)	−0.0014 (10)	−0.0022 (8)	−0.0095 (10)
C7	0.0511 (12)	0.0472 (12)	0.0533 (11)	0.0028 (10)	−0.0023 (10)	−0.0126 (10)
C8	0.0437 (11)	0.0478 (13)	0.0559 (12)	0.0066 (10)	−0.0037 (10)	−0.0100 (11)
C9	0.0352 (8)	0.0428 (11)	0.0366 (8)	0.0009 (8)	−0.0008 (7)	0.0006 (8)
C10	0.0375 (9)	0.0422 (11)	0.0344 (9)	0.0004 (8)	0.0017 (7)	0.0000 (8)
C11	0.0377 (9)	0.0537 (13)	0.0399 (9)	−0.0009 (9)	−0.0029 (8)	−0.0019 (9)
C12	0.0446 (11)	0.0533 (13)	0.0413 (10)	0.0031 (10)	−0.0046 (8)	−0.0036 (10)
C13	0.0517 (12)	0.0627 (15)	0.0449 (10)	−0.0012 (11)	−0.0088 (10)	0.0009 (11)
C14	0.0600 (14)	0.091 (2)	0.0444 (11)	−0.0117 (15)	−0.0081 (11)	−0.0034 (14)
C15	0.0662 (16)	0.114 (3)	0.0515 (13)	−0.0215 (18)	−0.0198 (13)	0.0205 (17)
C16	0.119 (3)	0.134 (4)	0.0706 (19)	0.068 (3)	−0.033 (2)	−0.015 (2)
C17	0.0427 (10)	0.0498 (12)	0.0455 (10)	0.0049 (9)	−0.0013 (8)	0.0111 (10)
C18	0.0795 (19)	0.0494 (16)	0.104 (2)	0.0190 (15)	−0.0285 (18)	−0.0098 (16)
C19	0.0365 (10)	0.0651 (16)	0.0518 (11)	0.0027 (10)	−0.0034 (8)	−0.0005 (11)
C20	0.0588 (15)	0.0728 (19)	0.0595 (15)	0.0207 (14)	−0.0111 (12)	−0.0064 (14)

Geometric parameters (Å, º)

O6—C6	1.416 (2)	C7—C8	1.529 (3)
O6—H6	0.820	C7—H7A	0.970
O12—C17	1.343 (3)	C7—H7B	0.970
O12—C12	1.463 (3)	C8—C18	1.523 (4)
O16—C15	1.338 (5)	C8—C9	1.555 (3)
O16—C16	1.375 (4)	C8—H8	0.980
O17—C17	1.197 (3)	C9—C17	1.522 (3)
O19—C20	1.354 (4)	C9—C11	1.535 (3)
O19—C19	1.469 (3)	C9—C10	1.552 (3)
O20—C20	1.206 (3)	C10—H10	0.980
C1—C10	1.525 (3)	C11—C12	1.527 (3)
C1—C2	1.533 (3)	C11—H11A	0.970
C1—H1A	0.970	C11—H11B	0.970
C1—H1B	0.970	C12—C13	1.488 (3)
C2—C3	1.493 (4)	C12—H12	0.980
C2—H2A	0.970	C13—C16	1.330 (5)
C2—H2B	0.970	C13—C14	1.416 (3)
C3—C4	1.326 (4)	C14—C15	1.313 (5)
C3—H3	0.930	C14—H14	0.930
C4—C20	1.474 (4)	C15—H15	0.930
C4—C5	1.503 (3)	C16—H16	0.930
C5—C19	1.544 (3)	C18—H18A	0.960
C5—C6	1.545 (3)	C18—H18B	0.960
C5—C10	1.550 (3)	C18—H18C	0.960
C6—C7	1.504 (4)	C19—H19A	0.970
C6—H6A	0.980	C19—H19B	0.970
C6—O6—H6	109.5	C11—C9—C8	109.79 (17)
C17—O12—C12	112.28 (16)	C10—C9—C8	109.74 (16)
C15—O16—C16	106.1 (3)	C1—C10—C5	111.50 (17)
C20—O19—C19	110.0 (2)	C1—C10—C9	117.54 (16)
C10—C1—C2	108.58 (18)	C5—C10—C9	115.24 (18)
C10—C1—H1A	110.0	C1—C10—H10	103.4
C2—C1—H1A	110.0	C5—C10—H10	103.4
C10—C1—H1B	110.0	C9—C10—H10	103.4
C2—C1—H1B	110.0	C12—C11—C9	106.35 (17)
H1A—C1—H1B	108.4	C12—C11—H11A	110.5
C3—C2—C1	110.4 (2)	C9—C11—H11A	110.5
C3—C2—H2A	109.6	C12—C11—H11B	110.5
C1—C2—H2A	109.6	C9—C11—H11B	110.5
C3—C2—H2B	109.6	H11A—C11—H11B	108.6
C1—C2—H2B	109.6	O12—C12—C13	109.0 (2)
H2A—C2—H2B	108.1	O12—C12—C11	104.57 (17)
C4—C3—C2	122.0 (2)	C13—C12—C11	116.00 (19)
C4—C3—H3	119.0	O12—C12—H12	109.0
C2—C3—H3	119.0	C13—C12—H12	109.0
C3—C4—C20	122.4 (3)	C11—C12—H12	109.0
C3—C4—C5	126.2 (2)	C16—C13—C14	105.1 (3)
C20—C4—C5	106.3 (3)	C16—C13—C12	128.6 (3)
C4—C5—C19	97.35 (18)	C14—C13—C12	126.3 (3)
C4—C5—C6	112.34 (17)	C15—C14—C13	108.0 (3)
C19—C5—C6	110.2 (2)	C15—C14—H14	126.0
C4—C5—C10	109.7 (2)	C13—C14—H14	126.0
C19—C5—C10	121.52 (17)	C14—C15—O16	110.5 (2)
C6—C5—C10	105.68 (16)	C14—C15—H15	124.8
O6—C6—C7	112.8 (2)	O16—C15—H15	124.8
O6—C6—C5	112.80 (18)	C13—C16—O16	110.4 (3)
C7—C6—C5	109.75 (17)	C13—C16—H16	124.8
O6—C6—H6A	107.1	O16—C16—H16	124.8
C7—C6—H6A	107.1	O17—C17—O12	120.7 (2)
C5—C6—H6A	107.1	O17—C17—C9	128.0 (2)
C6—C7—C8	114.3 (2)	O12—C17—C9	111.30 (19)
C6—C7—H7A	108.7	C8—C18—H18A	109.5
C8—C7—H7A	108.7	C8—C18—H18B	109.5
C6—C7—H7B	108.7	H18A—C18—H18B	109.5
C8—C7—H7B	108.7	C8—C18—H18C	109.5
H7A—C7—H7B	107.6	H18A—C18—H18C	109.5
C18—C8—C7	109.6 (2)	H18B—C18—H18C	109.5
C18—C8—C9	113.3 (2)	O19—C19—C5	104.83 (18)
C7—C8—C9	113.99 (18)	O19—C19—H19A	110.8
C18—C8—H8	106.5	C5—C19—H19A	110.8
C7—C8—H8	106.5	O19—C19—H19B	110.8
C9—C8—H8	106.5	C5—C19—H19B	110.8
C17—C9—C11	102.43 (16)	H19A—C19—H19B	108.9
C17—C9—C10	111.84 (16)	O20—C20—O19	121.2 (3)
C11—C9—C10	111.00 (18)	O20—C20—C4	131.8 (3)
C17—C9—C8	111.9 (2)	O19—C20—C4	106.9 (2)
C10—C1—C2—C3	−53.5 (3)	C11—C9—C10—C5	−172.53 (17)
C1—C2—C3—C4	23.4 (4)	C8—C9—C10—C5	−51.0 (2)
C2—C3—C4—C20	−152.1 (3)	C17—C9—C11—C12	16.4 (2)
C2—C3—C4—C5	−0.9 (4)	C10—C9—C11—C12	−103.1 (2)
C3—C4—C5—C19	−118.1 (3)	C8—C9—C11—C12	135.3 (2)
C20—C4—C5—C19	36.9 (2)	C17—O12—C12—C13	135.9 (2)
C3—C4—C5—C6	126.5 (3)	C17—O12—C12—C11	11.2 (3)
C20—C4—C5—C6	−78.5 (2)	C9—C11—C12—O12	−17.0 (3)
C3—C4—C5—C10	9.2 (3)	C9—C11—C12—C13	−137.2 (2)
C20—C4—C5—C10	164.2 (2)	O12—C12—C13—C16	−97.5 (4)
C4—C5—C6—O6	51.7 (3)	C11—C12—C13—C16	20.1 (5)
C19—C5—C6—O6	−55.7 (3)	O12—C12—C13—C14	79.8 (4)
C10—C5—C6—O6	171.35 (19)	C11—C12—C13—C14	−162.5 (3)
C4—C5—C6—C7	178.3 (2)	C16—C13—C14—C15	1.0 (4)
C19—C5—C6—C7	71.0 (2)	C12—C13—C14—C15	−176.9 (3)
C10—C5—C6—C7	−62.0 (2)	C13—C14—C15—O16	−1.0 (4)
O6—C6—C7—C8	−174.34 (19)	C16—O16—C15—C14	0.6 (5)
C5—C6—C7—C8	59.0 (3)	C14—C13—C16—O16	−0.7 (5)
C6—C7—C8—C18	−176.8 (2)	C12—C13—C16—O16	177.1 (3)
C6—C7—C8—C9	−48.7 (3)	C15—O16—C16—C13	0.1 (6)
C18—C8—C9—C17	43.8 (3)	C12—O12—C17—O17	179.7 (2)
C7—C8—C9—C17	−82.4 (2)	C12—O12—C17—C9	−0.5 (3)
C18—C8—C9—C11	−69.2 (3)	C11—C9—C17—O17	169.5 (3)
C7—C8—C9—C11	164.6 (2)	C10—C9—C17—O17	−71.6 (3)
C18—C8—C9—C10	168.5 (2)	C8—C9—C17—O17	52.0 (3)
C7—C8—C9—C10	42.3 (3)	C11—C9—C17—O12	−10.2 (3)
C2—C1—C10—C5	64.2 (2)	C10—C9—C17—O12	108.7 (2)
C2—C1—C10—C9	−159.55 (19)	C8—C9—C17—O12	−127.7 (2)
C4—C5—C10—C1	−40.6 (2)	C20—O19—C19—C5	19.0 (3)
C19—C5—C10—C1	71.7 (3)	C4—C5—C19—O19	−33.3 (2)
C6—C5—C10—C1	−161.92 (18)	C6—C5—C19—O19	83.8 (2)
C4—C5—C10—C9	−177.89 (17)	C10—C5—C19—O19	−151.9 (2)
C19—C5—C10—C9	−65.6 (3)	C19—O19—C20—O20	−178.2 (3)
C6—C5—C10—C9	60.8 (2)	C19—O19—C20—C4	5.0 (3)
C17—C9—C10—C1	−60.9 (2)	C3—C4—C20—O20	−48.2 (5)
C11—C9—C10—C1	52.8 (2)	C5—C4—C20—O20	155.6 (3)
C8—C9—C10—C1	174.36 (19)	C3—C4—C20—O19	128.1 (3)
C17—C9—C10—C5	73.8 (2)	C5—C4—C20—O19	−28.1 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O6—H6···O20^i	0.82	1.94	2.754 (3)	171
C15—H15···O6^ii	0.93	2.43	3.292 (3)	155
C2—H2A···O6^iii	0.97	2.48	3.424 (3)	164
C12—H12···O17^iv	0.98	2.57	3.488 (3)	156

Symmetry codes: (i) −x+1, y+1/2, −z+2; (ii) x−1, y, z−1; (iii) −x, y−1/2, −z+2; (iv) −x, y−1/2, −z+1.