Furan­oeudesmane-B, a new eudesmane sesquiterpenoid from Myoporum bontioides

Myoporum bontioides is a folk medicinal plant from the northwest of China and is known as a superficies-syndrome drug. The EtOH extract from the dried root of Myoporum bontioides was chromatographed to give furan­oeudesmane-B, a new eudesmane sesquiterpenoid. The structure of furan­oeudesmane-B (3[beta]-angloyl­oxy-4[alpha]-acetoxy-5[alpha]H-furan­oeudesmane), C₂₂H₃₀O₅, has not been determined by X-ray crystallography before.

S1. Comment

In the course of a search for bioactive drugs, Myoporum bontioides, which is widespread in the northwest of China, was selected as it has efficiency as an antipyretic and detoxicate, and is used for relieving uneasiness and fever in folk medicine. A study with somewhat larger amounts of the plant material and careful chromatography have allowed the isolation of 3β-angloyloxy-4αacetoxy-5αH-furanoeudesmane, named Furanoeudesmane-B. The title compound, (I), was a new eudesmane sesquiterpenoid. Several similar eudesmane derivatives (Bohlmann & Zdero, 1977) and quite a few eremophilane sesquiterpenoids (Bohlmann et al., 1978, 1979), which have the same elemental composition as the title compound, have been reported previously. \scheme

The skeleton of Furanoeudesmane consists of two six-membered rings and a furan ring connected together (labelled A–C left-to-right in the Scheme). Ring A (C1–C5 and C10) takes a chair conformation, with C4 0.653 (3) Å above and C1 0.609 (4) Å below the plane; ring B (C5–C10) takes a half-chair conformation as a result of the neighbouring furan ring, with C10 0.662 (3) Å above. Furan ring C (C7, C8, C11, C12 and O1) is essentially planar, including the C13 methyl group. The dihedral angle between the planar parts of rings A and B is 32.4 (2)°, and 34.0 (2)° between the planar segment of A and C; the planar segments of B and C are almost coplanar, the dihedral angle being only 4.6 (2)°.

S2. Experimental

The EtOH extract of Myoporum bontioides was chromatographed on a silica-gel column using stepwise solvent gradient method (EtOH/petroleum ether). The title compound was obtained from the 12% EtOH/petroleum ether fraction (0.02% dry wt) and crystallized from EtOH yielding colourless crystals (m.p. 474–475 K). Its molecular formula was determined as C₂₂H₃₀O₅ from the mass spectrum and elemental analysis. The experimental sample was recrystallized from ethyl alchol/acetone.

S3. Refinement

The data set is complete to about θ = 27°, but beyond that some data are missing due to locally imposed instrumental conditions. The data set contained no Friedel pairs; anomalous dispersion effects are negigible.

Computing details

Data collection: CAD-4 Users Manual (Enraf-Nonius, 1985); cell refinement: CAD-4 Users Manual; data reduction: Xtal3.4 ADDREF SORTRF (Hall et al., 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: Xtal3.4 CRYLSQ; molecular graphics: Xtal3.4; software used to prepare material for publication: Xtal3.4 BONDLA CIFIO.

3β-angloyloxy-4αacetoxy-5αH-furanoeudesmane

Crystal data

C22H30O5	Dx = 1.309 Mg m^−3
Mr = 374.46	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 20 reflections
a = 8.854 (1) Å	θ = 8.0–15.5°
b = 12.122 (1) Å	µ = 0.09 mm^−1
c = 17.708 (2) Å	T = 293 K
V = 1900.6 (3) Å^3	Block, colourless
Z = 4	0.4 × 0.3 × 0.2 mm
F(000) = 808

Data collection

Enraf-Nonius CAD-4 diffractometer	Rint = 0.048
Radiation source: fine-focus sealed tube	θmax = 28.7°
Graphite monochromator	h = −10→10
ω–2θ scans	k = 0→14
4692 measured reflections	l = 0→23
2348 independent reflections	3 standard reflections every 60 min
2348 reflections with F^2 > 0	intensity decay: 0.1%

Refinement

Refinement on F^2	2 restraints
Least-squares matrix: full	0 constraints
R[F^2 > 2σ(F^2)] = 0.040	H-atom parameters not refined
wR(F^2) = 0.039	Calculateda w = 1/[σ^2(Fo^2) + (0.1253P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.42	(Δ/σ)max = 0.011
2347 reflections	Δρmax = 0.34 e Å^−3
244 parameters	Δρmin = −0.23 e Å^−3

Special details

Experimental. The data set is not complete beyond approx. theta = 27 degrees due to instrumental restrictions

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

	x	y	z	Uiso*/Ueq
O1	0.8868 (2)	−0.33387 (13)	1.13666 (9)	0.0627 (10)
O2	0.7934 (2)	0.08168 (12)	0.94647 (8)	0.0542 (9)
O3	0.8237 (2)	−0.05402 (15)	0.87217 (9)	0.0808 (13)
O4	1.0715 (2)	0.17485 (13)	0.90985 (8)	0.0625 (10)
O5	1.1944 (3)	0.1088 (2)	0.82234 (11)	0.1156 (18)
C1	1.2085 (3)	−0.0684 (2)	1.01138 (13)	0.0658 (16)
H1A	1.29940	−0.07730	1.03680	0.08000*
H1B	1.19020	−0.12720	0.97540	0.08000*
C2	1.2133 (3)	0.0483 (2)	0.98130 (13)	0.0662 (16)
H2A	1.22960	0.10770	1.01990	0.08000*
H2B	1.29550	0.05410	0.96060	0.08000*
C3	1.0728 (3)	0.06705 (18)	0.94176 (11)	0.0552 (13)
H3	1.05840	0.02080	0.90440	0.08000*
C4	0.9330 (3)	0.06386 (17)	0.98797 (10)	0.0497 (12)
C5	0.9232 (3)	−0.05092 (17)	1.02170 (11)	0.0459 (11)
H5	0.91000	−0.10010	0.97770	0.08000*
C6	0.7839 (3)	−0.06505 (18)	1.06645 (12)	0.0546 (13)
H6A	0.77790	−0.00250	1.10050	0.08000*
H6B	0.69110	−0.05390	1.04330	0.08000*
C7	0.7883 (3)	−0.17564 (18)	1.10221 (11)	0.0527 (12)
C8	0.9100 (3)	−0.23626 (18)	1.10075 (12)	0.0525 (13)
C9	1.0591 (3)	−0.2146 (2)	1.06945 (12)	0.0583 (14)
H9A	1.13390	−0.23160	1.08940	0.08000*
H9B	1.06630	−0.24970	1.02950	0.08000*
C10	1.0720 (3)	−0.08926 (17)	1.05685 (11)	0.0504 (12)
C11	0.6762 (3)	−0.23234 (19)	1.13978 (14)	0.0585 (14)
C12	0.7415 (3)	−0.3262 (2)	1.15965 (13)	0.0684 (17)
H12	0.70720	−0.39950	1.18540	0.08000*
C13	0.5154 (3)	−0.1954 (2)	1.15280 (15)	0.084 (2)
H13A	0.50210	−0.12250	1.13330	0.12500*
H13B	0.49590	−0.19370	1.20710	0.12500*
H13C	0.44720	−0.24530	1.12970	0.12500*
C14	0.9241 (3)	0.16239 (18)	1.03529 (13)	0.0669 (15)
H14A	0.83220	0.15890	1.06530	0.10300*
H14B	0.92220	0.22680	1.00490	0.10300*
H14C	1.00890	0.16440	1.06910	0.10300*
C15	0.7592 (3)	0.02475 (19)	0.89090 (13)	0.0601 (15)
C16	0.6200 (3)	0.0705 (2)	0.85794 (17)	0.085 (2)
H16A	0.59260	0.13700	0.88470	0.12400*
H16B	0.54170	0.01780	0.86150	0.12400*
H16C	0.63910	0.08890	0.80590	0.12400*
C17	1.1330 (3)	0.1847 (2)	0.84955 (13)	0.0719 (18)
C18	1.1106 (4)	0.3026 (3)	0.82369 (14)	0.095 (2)
C19	1.2114 (5)	0.3447 (3)	0.78680 (15)	0.099 (2)
H19	1.17730	0.43070	0.76930	0.08000*
C20	0.9568 (4)	0.3584 (2)	0.84507 (18)	0.098 (2)
H20A	0.89630	0.30910	0.87330	0.14700*
H20B	0.90370	0.37970	0.79920	0.14700*
H20C	0.97580	0.42470	0.87390	0.14700*
C21	1.3502 (4)	0.2963 (3)	0.76509 (16)	0.089 (2)
H21A	1.40890	0.34900	0.73690	0.12900*
H21B	1.33290	0.23220	0.73540	0.12900*
H21C	1.40650	0.27610	0.81010	0.12900*
C22	1.0972 (3)	−0.0324 (2)	1.12993 (11)	0.0675 (15)
H22A	1.01040	−0.04490	1.16010	0.09500*
H22B	1.11030	0.04370	1.11940	0.09500*
H22C	1.18480	−0.06350	1.15200	0.09500*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0742 (13)	0.0503 (9)	0.0636 (9)	−0.0061 (9)	−0.0125 (9)	0.0204 (8)
O2	0.0694 (11)	0.0432 (7)	0.0501 (8)	0.0102 (8)	−0.0033 (9)	−0.0003 (7)
O3	0.1002 (15)	0.0737 (12)	0.0685 (11)	0.0227 (11)	−0.0245 (10)	−0.0230 (9)
O4	0.0942 (13)	0.0486 (9)	0.0448 (7)	−0.0111 (10)	−0.0053 (9)	0.0085 (7)
O5	0.187 (3)	0.0850 (15)	0.0751 (13)	0.0063 (18)	0.0457 (16)	0.0322 (11)
C1	0.0546 (16)	0.0823 (18)	0.0606 (13)	0.0050 (15)	0.0057 (12)	0.0274 (13)
C2	0.0521 (16)	0.086 (2)	0.0601 (13)	−0.0063 (15)	0.0048 (13)	0.0098 (14)
C3	0.0752 (17)	0.0423 (12)	0.0481 (11)	−0.0103 (12)	0.0015 (13)	0.0016 (10)
C4	0.0693 (16)	0.0401 (12)	0.0398 (9)	−0.0006 (12)	−0.0039 (11)	0.0030 (9)
C5	0.0541 (14)	0.0383 (10)	0.0454 (10)	−0.0006 (11)	0.0013 (11)	0.0007 (8)
C6	0.0610 (16)	0.0428 (12)	0.0602 (12)	0.0011 (11)	0.0045 (12)	0.0071 (10)
C7	0.0549 (14)	0.0586 (13)	0.0444 (10)	−0.0055 (14)	−0.0007 (12)	0.0065 (11)
C8	0.0595 (14)	0.0515 (14)	0.0465 (11)	−0.0080 (12)	−0.0081 (12)	0.0096 (10)
C9	0.0613 (17)	0.0551 (13)	0.0586 (12)	0.0105 (12)	−0.0078 (12)	0.0095 (11)
C10	0.0549 (15)	0.0466 (12)	0.0498 (10)	−0.0015 (12)	−0.0034 (12)	0.0091 (10)
C11	0.0672 (16)	0.0561 (14)	0.0522 (12)	−0.0072 (13)	0.0004 (12)	0.0064 (11)
C12	0.078 (2)	0.0638 (15)	0.0635 (14)	−0.0179 (16)	−0.0090 (14)	0.0156 (13)
C13	0.078 (2)	0.092 (2)	0.0818 (19)	−0.0131 (18)	0.0103 (16)	0.0078 (16)
C14	0.109 (2)	0.0380 (10)	0.0534 (12)	−0.0093 (15)	−0.0009 (15)	−0.0025 (10)
C15	0.0723 (18)	0.0510 (14)	0.0570 (13)	0.0069 (14)	0.0022 (13)	−0.0043 (12)
C16	0.087 (2)	0.0786 (19)	0.0893 (19)	0.0092 (17)	−0.0247 (17)	0.0031 (17)
C17	0.100 (2)	0.0655 (18)	0.0501 (15)	−0.0093 (15)	0.0075 (15)	0.0151 (13)
C18	0.143 (3)	0.097 (2)	0.0454 (14)	−0.048 (2)	−0.0150 (18)	0.0133 (15)
C19	0.150 (4)	0.095 (2)	0.0527 (16)	−0.009 (3)	−0.009 (2)	0.0051 (15)
C20	0.110 (3)	0.076 (2)	0.106 (2)	0.0336 (18)	−0.002 (2)	0.0267 (16)
C21	0.100 (2)	0.105 (2)	0.0621 (16)	0.004 (2)	0.0281 (16)	0.0054 (16)
C22	0.0793 (19)	0.0721 (15)	0.0511 (12)	−0.0177 (15)	−0.0095 (13)	0.0038 (12)

Geometric parameters (Å, º)

O1—C8	1.359 (3)	C9—C10	1.539 (3)
O1—C12	1.352 (3)	C10—C22	1.483 (3)
O2—C4	1.454 (3)	C11—C12	1.325 (3)
O2—C15	1.240 (3)	C11—C13	1.510 (4)
O3—C15	1.161 (3)	C12—H12	1.043 (3)
O4—C3	1.424 (3)	C13—H13A	0.956 (3)
O4—C17	1.205 (3)	C13—H13B	0.977 (3)
O5—C17	1.172 (4)	C13—H13C	0.948 (3)
C1—H1A	0.929 (3)	C14—H14A	0.973 (3)
C1—H1B	0.970 (3)	C14—H14B	0.948 (2)
C1—C2	1.512 (4)	C14—H14C	0.960 (3)
C1—C10	1.474 (3)	C15—C16	1.472 (4)
C2—H2A	1.003 (3)	C16—H16A	0.966 (3)
C2—H2B	0.818 (2)	C16—H16B	0.945 (3)
C2—C3	1.445 (3)	C16—H16C	0.963 (3)
C3—H3	0.876 (2)	C17—C18	1.514 (4)
C3—C4	1.484 (3)	C18—C19	1.218 (5)
C4—C5	1.517 (3)	C18—C20	1.567 (5)
C4—C14	1.461 (3)	C19—H19	1.129 (3)
C5—H5	0.988 (2)	C19—C21	1.415 (5)
C5—C6	1.476 (3)	C20—H20A	0.946 (3)
C5—C10	1.529 (3)	C20—H20B	0.973 (3)
C6—H6A	0.970 (2)	C20—H20C	0.966 (3)
C6—H6B	0.928 (2)	C21—H21A	0.963 (3)
C6—C7	1.483 (3)	C21—H21B	0.950 (3)
C7—C8	1.305 (3)	C21—H21C	0.972 (3)
C7—C11	1.379 (3)	C22—H22A	0.948 (2)
C8—C9	1.456 (4)	C22—H22B	0.949 (3)
C9—H9A	0.779 (2)	C22—H22C	0.946 (3)
C9—H9B	0.828 (2)
C8—O1—C12	103.03 (18)	C9—C10—C22	110.05 (17)
C4—O2—C15	121.78 (18)	C7—C11—C12	104.0 (2)
C3—O4—C17	116.0 (2)	C7—C11—C13	127.2 (2)
H1A—C1—H1B	112.2 (3)	C12—C11—C13	128.8 (2)
H1A—C1—C2	104.8 (2)	O1—C12—C11	113.2 (2)
H1A—C1—C10	115.2 (2)	O1—C12—H12	110.5 (2)
H1B—C1—C2	117.5 (2)	C11—C12—H12	136.1 (3)
H1B—C1—C10	95.5 (2)	C11—C13—H13A	109.6 (3)
C2—C1—C10	112.1 (2)	C11—C13—H13B	108.8 (3)
C1—C2—H2A	115.8 (2)	C11—C13—H13C	110.2 (3)
C1—C2—H2B	105.3 (3)	H13A—C13—H13B	108.4 (3)
C1—C2—C3	107.1 (2)	H13A—C13—H13C	110.9 (3)
H2A—C2—H2B	96.6 (3)	H13B—C13—H13C	109.0 (3)
H2A—C2—C3	109.9 (2)	C4—C14—H14A	108.8 (2)
H2B—C2—C3	122.4 (2)	C4—C14—H14B	110.4 (2)
O4—C3—C2	110.1 (2)	C4—C14—H14C	109.6 (2)
O4—C3—H3	106.64 (18)	H14A—C14—H14B	109.3 (3)
O4—C3—C4	103.64 (18)	H14A—C14—H14C	108.3 (2)
C2—C3—H3	113.0 (2)	H14B—C14—H14C	110.3 (3)
C2—C3—C4	116.51 (18)	O2—C15—O3	124.3 (2)
H3—C3—C4	106.2 (2)	O2—C15—C16	108.0 (2)
O2—C4—C3	115.23 (16)	O3—C15—C16	127.5 (2)
O2—C4—C5	106.67 (18)	C15—C16—H16A	109.3 (3)
O2—C4—C14	97.05 (19)	C15—C16—H16B	109.4 (3)
C3—C4—C5	106.78 (18)	C15—C16—H16C	108.7 (3)
C3—C4—C14	109.9 (2)	H16A—C16—H16B	110.3 (3)
C5—C4—C14	121.40 (17)	H16A—C16—H16C	108.7 (3)
C4—C5—H5	104.46 (16)	H16B—C16—H16C	110.4 (3)
C4—C5—C6	111.44 (19)	O4—C17—O5	119.7 (3)
C4—C5—C10	112.95 (19)	O4—C17—C18	107.6 (2)
H5—C5—C6	104.7 (2)	O5—C17—C18	132.7 (2)
H5—C5—C10	103.88 (19)	C17—C18—C19	117.5 (3)
C6—C5—C10	117.78 (17)	C17—C18—C20	116.6 (3)
C5—C6—H6A	106.8 (2)	C19—C18—C20	125.9 (3)
C5—C6—H6B	119.1 (2)	C18—C19—H19	109.7 (3)
C5—C6—C7	108.18 (19)	C18—C19—C21	127.5 (3)
H6A—C6—H6B	96.4 (2)	H19—C19—C21	122.7 (3)
H6A—C6—C7	116.3 (2)	C18—C20—H20A	110.3 (3)
H6B—C6—C7	110.1 (2)	C18—C20—H20B	109.4 (3)
C6—C7—C8	121.5 (2)	C18—C20—H20C	109.6 (3)
C6—C7—C11	129.6 (2)	H20A—C20—H20B	109.5 (4)
C8—C7—C11	108.9 (2)	H20A—C20—H20C	110.2 (3)
O1—C8—C7	110.9 (2)	H20B—C20—H20C	107.7 (3)
O1—C8—C9	118.2 (2)	C19—C21—H21A	109.5 (3)
C7—C8—C9	130.9 (2)	C19—C21—H21B	110.5 (3)
C8—C9—H9A	123.4 (2)	C19—C21—H21C	109.1 (3)
C8—C9—H9B	107.6 (2)	H21A—C21—H21B	110.0 (3)
C8—C9—C10	107.5 (2)	H21A—C21—H21C	108.4 (3)
H9A—C9—H9B	100.7 (3)	H21B—C21—H21C	109.3 (3)
H9A—C9—C10	105.3 (2)	C10—C22—H22A	107.2 (2)
H9B—C9—C10	112.2 (2)	C10—C22—H22B	107.4 (2)
C1—C10—C5	115.57 (18)	C10—C22—H22C	107.4 (2)
C1—C10—C9	108.0 (2)	H22A—C22—H22B	111.4 (3)
C1—C10—C22	105.9 (2)	H22A—C22—H22C	111.6 (2)
C5—C10—C9	107.15 (19)	H22B—C22—H22C	111.6 (3)
C5—C10—C22	110.11 (19)