A clerodane diterpenoid from Pulicaria wightiana

The structure of the clerodane diterpene C₂₁H₃₀O₅, with modest antibacterial activity and isolated from the plant Pulicaria wightiana, was established to be meth­yl 6α-hydr­oxy-3,13-clerodadien-15,16-olid-18-oate. The fused six-membered rings of the deca­lin system have sofa and chair conformations. The furan­one side chain is in an antiperiplanar conformation. The mol­ecules in the crystal structure are stabilized by an intra­molecular O—H...O hydrogen bond and a chain of inter­molecular C—H...O inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.043
• wR factor = 0.120
• Data-to-parameter ratio = 10.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT410_ALERT_2_C Short Intra H...H Contact  H1A    ..  H11B    ..       1.98 Ang.

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           28.00
           From the CIF: _reflns_number_total               2549
           Count of symmetry unique reflns         2583
           Completeness (_total/calc)             98.68%
           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
   1 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
   1 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, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1990) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1995).

methyl 6α-hydroxy-3,13-clerodadien-15,16-olid-18-oate

Crystal data

C21H30O5	F(000) = 784
Mr = 362.45	Dx = 1.277 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 9796 reflections
a = 10.3572 (5) Å	θ = 2.2–28.0°
b = 11.6812 (5) Å	µ = 0.09 mm^−1
c = 15.5784 (7) Å	T = 273 K
V = 1884.75 (15) Å^3	Needle, colorless
Z = 4	0.30 × 0.14 × 0.09 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2386 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.019
Graphite monochromator	θmax = 28.0°, θmin = 2.2°
ω scans	h = −13→13
16247 measured reflections	k = −14→15
2549 independent reflections	l = −20→20

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0837P)^2 + 0.187P] where P = (Fo^2 + 2Fc^2)/3
2549 reflections	(Δ/σ)max < 0.001
240 parameters	Δρmax = 0.28 e Å^−3
0 restraints	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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.35265 (19)	0.45141 (14)	1.11395 (9)	0.0594 (4)
H1	0.3800	0.4023	1.1469	0.089*
O2	0.2912 (3)	0.1551 (2)	0.44294 (11)	0.0936 (8)
O3	0.1218 (2)	0.18395 (16)	0.52905 (11)	0.0705 (5)
O4	0.3820 (2)	0.08839 (15)	1.16640 (10)	0.0652 (5)
O5	0.4445 (2)	0.26636 (14)	1.19287 (9)	0.0647 (5)
C1	0.5140 (2)	0.20411 (17)	0.87041 (11)	0.0442 (4)
H1A	0.5061	0.1975	0.8086	0.053*
H1B	0.6022	0.2257	0.8837	0.053*
C2	0.4833 (3)	0.09069 (17)	0.91170 (13)	0.0546 (5)
H2A	0.4103	0.0563	0.8825	0.066*
H2B	0.5566	0.0398	0.9052	0.066*
C3	0.4524 (2)	0.10288 (17)	1.00462 (12)	0.0470 (4)
H3	0.4441	0.0359	1.0364	0.056*
C4	0.43565 (16)	0.20137 (15)	1.04620 (10)	0.0360 (3)
C5	0.44603 (16)	0.32013 (14)	1.00170 (9)	0.0329 (3)
C6	0.33756 (18)	0.40344 (15)	1.03061 (11)	0.0380 (4)
H6	0.2556	0.3615	1.0295	0.046*
C7	0.3243 (2)	0.50658 (15)	0.97230 (12)	0.0448 (4)
H7A	0.4023	0.5522	0.9768	0.054*
H7B	0.2532	0.5532	0.9928	0.054*
C8	0.30129 (19)	0.47899 (16)	0.87832 (12)	0.0430 (4)
H8	0.2210	0.4348	0.8751	0.052*
C9	0.41007 (16)	0.40201 (15)	0.84263 (10)	0.0363 (3)
C10	0.42112 (15)	0.29636 (13)	0.90344 (9)	0.0316 (3)
H10	0.3357	0.2604	0.9014	0.038*
C11	0.37563 (18)	0.36333 (17)	0.74991 (11)	0.0419 (4)
H11A	0.3695	0.4313	0.7144	0.050*
H11B	0.4471	0.3182	0.7282	0.050*
C12	0.2528 (2)	0.2944 (2)	0.73759 (12)	0.0537 (5)
H12A	0.2548	0.2289	0.7758	0.064*
H12B	0.1795	0.3414	0.7537	0.064*
C13	0.2337 (2)	0.25295 (16)	0.64782 (11)	0.0449 (4)
C14	0.3179 (2)	0.2339 (2)	0.58554 (13)	0.0558 (5)
H14	0.4062	0.2477	0.5889	0.067*
C15	0.2507 (3)	0.18763 (19)	0.51082 (14)	0.0631 (6)
C16	0.1020 (3)	0.2250 (3)	0.61501 (15)	0.0647 (6)
H16A	0.0617	0.1666	0.6502	0.078*
H16B	0.0476	0.2926	0.6149	0.078*
C17	0.2790 (3)	0.5904 (2)	0.82861 (15)	0.0704 (7)
H17A	0.2037	0.6282	0.8506	0.106*
H17B	0.2667	0.5733	0.7689	0.106*
H17C	0.3527	0.6394	0.8352	0.106*
C18	0.42054 (19)	0.19146 (17)	1.14123 (11)	0.0434 (4)
C19	0.3710 (3)	0.0691 (3)	1.25795 (14)	0.0751 (8)
H19A	0.4557	0.0661	1.2829	0.113*
H19B	0.3273	−0.0021	1.2680	0.113*
H19C	0.3229	0.1304	1.2835	0.113*
C20	0.57988 (18)	0.37079 (18)	1.02397 (12)	0.0460 (4)
H20A	0.5972	0.3595	1.0839	0.069*
H20B	0.5804	0.4512	1.0113	0.069*
H20C	0.6451	0.3331	0.9905	0.069*
C21	0.5387 (2)	0.4674 (2)	0.83387 (14)	0.0542 (5)
H21A	0.5325	0.5213	0.7875	0.081*
H21B	0.6071	0.4142	0.8223	0.081*
H21C	0.5566	0.5075	0.8863	0.081*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0948 (12)	0.0507 (8)	0.0328 (6)	0.0209 (8)	0.0027 (7)	−0.0091 (6)
O2	0.149 (2)	0.0874 (13)	0.0448 (9)	0.0199 (15)	0.0110 (11)	−0.0198 (9)
O3	0.0965 (13)	0.0702 (10)	0.0449 (8)	−0.0039 (10)	−0.0134 (9)	−0.0161 (8)
O4	0.0960 (13)	0.0647 (10)	0.0351 (7)	−0.0165 (9)	0.0008 (8)	0.0098 (7)
O5	0.1014 (13)	0.0611 (9)	0.0315 (7)	0.0096 (10)	−0.0097 (8)	−0.0038 (6)
C1	0.0542 (10)	0.0478 (9)	0.0306 (7)	0.0121 (8)	0.0053 (7)	−0.0049 (7)
C2	0.0841 (14)	0.0411 (9)	0.0385 (9)	0.0133 (10)	0.0009 (10)	−0.0086 (8)
C3	0.0653 (12)	0.0381 (8)	0.0378 (9)	0.0058 (9)	−0.0008 (8)	0.0010 (7)
C4	0.0407 (8)	0.0386 (8)	0.0285 (7)	0.0034 (7)	−0.0014 (6)	0.0005 (6)
C5	0.0364 (7)	0.0347 (7)	0.0276 (7)	0.0015 (6)	0.0005 (6)	−0.0033 (6)
C6	0.0458 (8)	0.0364 (8)	0.0318 (8)	0.0048 (7)	0.0058 (7)	−0.0028 (7)
C7	0.0585 (10)	0.0358 (8)	0.0401 (9)	0.0086 (8)	−0.0005 (8)	−0.0025 (7)
C8	0.0506 (9)	0.0405 (8)	0.0380 (8)	0.0077 (7)	−0.0014 (7)	0.0014 (7)
C9	0.0395 (8)	0.0389 (8)	0.0305 (7)	−0.0032 (7)	0.0018 (6)	0.0036 (6)
C10	0.0347 (7)	0.0347 (7)	0.0255 (6)	0.0006 (6)	0.0008 (5)	−0.0016 (6)
C11	0.0482 (9)	0.0500 (9)	0.0275 (7)	−0.0005 (8)	0.0031 (7)	0.0049 (7)
C12	0.0537 (10)	0.0765 (14)	0.0310 (8)	−0.0119 (11)	0.0008 (7)	−0.0040 (9)
C13	0.0594 (10)	0.0424 (9)	0.0329 (8)	0.0023 (8)	−0.0044 (7)	0.0020 (7)
C14	0.0716 (13)	0.0567 (11)	0.0390 (9)	0.0149 (11)	−0.0001 (9)	0.0007 (9)
C15	0.1058 (19)	0.0449 (10)	0.0386 (10)	0.0156 (12)	−0.0028 (11)	−0.0025 (8)
C16	0.0710 (14)	0.0790 (15)	0.0440 (11)	−0.0048 (13)	−0.0052 (10)	−0.0140 (11)
C17	0.1038 (19)	0.0566 (13)	0.0508 (11)	0.0288 (14)	−0.0068 (13)	0.0092 (10)
C18	0.0464 (9)	0.0510 (9)	0.0326 (8)	0.0068 (8)	−0.0028 (7)	0.0028 (7)
C19	0.0923 (18)	0.0959 (19)	0.0371 (10)	−0.0178 (16)	−0.0017 (11)	0.0193 (12)
C20	0.0420 (8)	0.0541 (10)	0.0421 (9)	−0.0055 (8)	−0.0069 (7)	−0.0042 (8)
C21	0.0536 (10)	0.0604 (12)	0.0487 (10)	−0.0186 (10)	0.0042 (9)	0.0084 (10)

Geometric parameters (Å, º)

O1—C6	1.423 (2)	C8—H8	0.9800
O1—H1	0.8200	C9—C21	1.542 (2)
O2—C15	1.199 (3)	C9—C11	1.555 (2)
O3—C15	1.365 (4)	C9—C10	1.560 (2)
O3—C16	1.437 (3)	C10—H10	0.9800
O4—C18	1.328 (3)	C11—C12	1.518 (3)
O4—C19	1.448 (2)	C11—H11A	0.9700
O5—C18	1.214 (2)	C11—H11B	0.9700
C1—C2	1.507 (3)	C12—C13	1.493 (2)
C1—C10	1.533 (2)	C12—H12A	0.9700
C1—H1A	0.9700	C12—H12B	0.9700
C1—H1B	0.9700	C13—C14	1.324 (3)
C2—C3	1.489 (3)	C13—C16	1.493 (3)
C2—H2A	0.9700	C14—C15	1.460 (3)
C2—H2B	0.9700	C14—H14	0.9300
C3—C4	1.332 (3)	C16—H16A	0.9700
C3—H3	0.9300	C16—H16B	0.9700
C4—C18	1.493 (2)	C17—H17A	0.9600
C4—C5	1.554 (2)	C17—H17B	0.9600
C5—C20	1.547 (2)	C17—H17C	0.9600
C5—C6	1.553 (2)	C19—H19A	0.9600
C5—C10	1.577 (2)	C19—H19B	0.9600
C6—C7	1.515 (2)	C19—H19C	0.9600
C6—H6	0.9800	C20—H20A	0.9600
C7—C8	1.518 (3)	C20—H20B	0.9600
C7—H7A	0.9700	C20—H20C	0.9600
C7—H7B	0.9700	C21—H21A	0.9600
C8—C17	1.532 (3)	C21—H21B	0.9600
C8—C9	1.545 (2)	C21—H21C	0.9600
C6—O1—H1	109.5	C5—C10—H10	104.7
C15—O3—C16	108.82 (18)	C12—C11—C9	117.63 (14)
C18—O4—C19	117.11 (19)	C12—C11—H11A	107.9
C2—C1—C10	110.01 (15)	C9—C11—H11A	107.9
C2—C1—H1A	109.7	C12—C11—H11B	107.9
C10—C1—H1A	109.7	C9—C11—H11B	107.9
C2—C1—H1B	109.7	H11A—C11—H11B	107.2
C10—C1—H1B	109.7	C13—C12—C11	113.65 (16)
H1A—C1—H1B	108.2	C13—C12—H12A	108.8
C3—C2—C1	112.10 (16)	C11—C12—H12A	108.8
C3—C2—H2A	109.2	C13—C12—H12B	108.8
C1—C2—H2A	109.2	C11—C12—H12B	108.8
C3—C2—H2B	109.2	H12A—C12—H12B	107.7
C1—C2—H2B	109.2	C14—C13—C16	108.33 (18)
H2A—C2—H2B	107.9	C14—C13—C12	130.8 (2)
C4—C3—C2	125.69 (18)	C16—C13—C12	120.83 (18)
C4—C3—H3	117.2	C13—C14—C15	109.4 (2)
C2—C3—H3	117.2	C13—C14—H14	125.3
C3—C4—C18	115.40 (16)	C15—C14—H14	125.3
C3—C4—C5	123.03 (14)	O2—C15—O3	121.0 (3)
C18—C4—C5	121.24 (15)	O2—C15—C14	130.8 (3)
C20—C5—C6	110.09 (14)	O3—C15—C14	108.2 (2)
C20—C5—C4	107.66 (14)	O3—C16—C13	105.17 (19)
C6—C5—C4	112.32 (13)	O3—C16—H16A	110.7
C20—C5—C10	115.58 (13)	C13—C16—H16A	110.7
C6—C5—C10	105.87 (13)	O3—C16—H16B	110.7
C4—C5—C10	105.34 (13)	C13—C16—H16B	110.7
O1—C6—C7	104.11 (14)	H16A—C16—H16B	108.8
O1—C6—C5	115.60 (15)	C8—C17—H17A	109.5
C7—C6—C5	112.95 (14)	C8—C17—H17B	109.5
O1—C6—H6	108.0	H17A—C17—H17B	109.5
C7—C6—H6	108.0	C8—C17—H17C	109.5
C5—C6—H6	108.0	H17A—C17—H17C	109.5
C6—C7—C8	115.06 (15)	H17B—C17—H17C	109.5
C6—C7—H7A	108.5	O5—C18—O4	121.28 (17)
C8—C7—H7A	108.5	O5—C18—C4	125.42 (18)
C6—C7—H7B	108.5	O4—C18—C4	113.24 (17)
C8—C7—H7B	108.5	O4—C19—H19A	109.5
H7A—C7—H7B	107.5	O4—C19—H19B	109.5
C7—C8—C17	109.32 (16)	H19A—C19—H19B	109.5
C7—C8—C9	110.86 (15)	O4—C19—H19C	109.5
C17—C8—C9	114.98 (17)	H19A—C19—H19C	109.5
C7—C8—H8	107.1	H19B—C19—H19C	109.5
C17—C8—H8	107.1	C5—C20—H20A	109.5
C9—C8—H8	107.1	C5—C20—H20B	109.5
C21—C9—C8	111.94 (16)	H20A—C20—H20B	109.5
C21—C9—C11	105.06 (14)	C5—C20—H20C	109.5
C8—C9—C11	109.64 (14)	H20A—C20—H20C	109.5
C21—C9—C10	112.48 (15)	H20B—C20—H20C	109.5
C8—C9—C10	107.19 (13)	C9—C21—H21A	109.5
C11—C9—C10	110.55 (14)	C9—C21—H21B	109.5
C1—C10—C9	113.47 (13)	H21A—C21—H21B	109.5
C1—C10—C5	110.29 (13)	C9—C21—H21C	109.5
C9—C10—C5	117.53 (13)	H21A—C21—H21C	109.5
C1—C10—H10	104.7	H21B—C21—H21C	109.5
C9—C10—H10	104.7
C10—C1—C2—C3	−41.0 (3)	C21—C9—C10—C5	67.06 (19)
C1—C2—C3—C4	8.6 (3)	C8—C9—C10—C5	−56.39 (18)
C2—C3—C4—C18	−173.2 (2)	C11—C9—C10—C5	−175.84 (14)
C2—C3—C4—C5	0.2 (3)	C20—C5—C10—C1	64.23 (19)
C3—C4—C5—C20	−101.4 (2)	C6—C5—C10—C1	−173.62 (14)
C18—C4—C5—C20	71.7 (2)	C4—C5—C10—C1	−54.46 (17)
C3—C4—C5—C6	137.26 (19)	C20—C5—C10—C9	−67.95 (19)
C18—C4—C5—C6	−49.7 (2)	C6—C5—C10—C9	54.19 (18)
C3—C4—C5—C10	22.5 (2)	C4—C5—C10—C9	173.36 (13)
C18—C4—C5—C10	−164.46 (15)	C21—C9—C11—C12	179.19 (18)
C20—C5—C6—O1	−44.7 (2)	C8—C9—C11—C12	−60.4 (2)
C4—C5—C6—O1	75.29 (19)	C10—C9—C11—C12	57.6 (2)
C10—C5—C6—O1	−170.26 (15)	C9—C11—C12—C13	−175.17 (17)
C20—C5—C6—C7	75.09 (19)	C11—C12—C13—C14	24.1 (3)
C4—C5—C6—C7	−164.95 (15)	C11—C12—C13—C16	−156.2 (2)
C10—C5—C6—C7	−50.50 (19)	C16—C13—C14—C15	−2.9 (3)
O1—C6—C7—C8	−177.65 (17)	C12—C13—C14—C15	176.9 (2)
C5—C6—C7—C8	56.2 (2)	C16—O3—C15—O2	178.5 (2)
C6—C7—C8—C17	175.47 (19)	C16—O3—C15—C14	−0.9 (3)
C6—C7—C8—C9	−56.8 (2)	C13—C14—C15—O2	−176.9 (3)
C7—C8—C9—C21	−70.56 (19)	C13—C14—C15—O3	2.5 (3)
C17—C8—C9—C21	54.1 (2)	C15—O3—C16—C13	−0.7 (3)
C7—C8—C9—C11	173.26 (15)	C14—C13—C16—O3	2.3 (3)
C17—C8—C9—C11	−62.1 (2)	C12—C13—C16—O3	−177.6 (2)
C7—C8—C9—C10	53.22 (19)	C19—O4—C18—O5	−0.6 (3)
C17—C8—C9—C10	177.84 (17)	C19—O4—C18—C4	177.0 (2)
C2—C1—C10—C9	−158.71 (15)	C3—C4—C18—O5	155.5 (2)
C2—C1—C10—C5	67.0 (2)	C5—C4—C18—O5	−18.1 (3)
C21—C9—C10—C1	−63.7 (2)	C3—C4—C18—O4	−21.9 (3)
C8—C9—C10—C1	172.87 (15)	C5—C4—C18—O4	164.52 (17)
C11—C9—C10—C1	53.42 (19)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O5	0.82	1.87	2.662 (2)	164
C20—H20A···O5	0.96	2.56	3.222 (3)	126
C19—H19C···O2^i	0.96	2.52	3.162 (3)	124

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