(1S,2R,3R,8R,10S)-3-Chloro-2,8-dihy-droxy-3,7-dimethyl-11-methyl-idene-13-oxabicyclo-[8.3.0]tridec-6-en-12-one.

The title compound, C(15)H(21)ClO(4), was synthesized from 9α-hy-droxy-parthenolide (9α-hy-droxy-4,8-dimethyl-12-methylen-3,14-dioxatricyclo-[9.3.0.0(2,4)]tetra-dec-7-en-13-one), which was isolated from the chloro-form extract of the aerial parts of Anvillea radiata. The mol-ecule is built up from fused five- and ten-membered rings. The five-membered lactone ring has an envelope conformation with the flap atom, C(H)-C-C(H), displaced by 0.2325 (15) Å from the mean plane through the remaining four atoms, whereas the ten-membered ring displays an approximate chair-chair conformation. The dihedral angle between the two rings is 66.4 (2)°. In the crystal, mol-ecules are linked into chains propagating along the a axis by O-H⋯O hydrogen bonds.

Related literature

For the isolation and biological activity of 9α-hy­droxy­parthenolide, see: El Hassany et al. (2004 ▶). For the reactivity of this sesquiterpene, see: Castaneda-Acosta et al. (1993 ▶); Neukirch et al. (2003 ▶); Hwang et al. (2006 ▶); Neelakantan et al. (2009 ▶). For conformational analysis, see: Cremer & Pople (1975 ▶)

Experimental

Crystal data

C15H21ClO4

M = 300.77

Orthorhombic,

a = 8.0224 (2) Å

b = 12.1532 (2) Å

c = 15.4147 (4) Å

V = 1502.90 (6) Å3

Z = 4

Mo Kα radiation

μ = 0.26 mm−1

T = 180 K

0.35 × 0.27 × 0.17 mm

Data collection

Agilent Xcalibur Eos Gemini ultra diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T min = 0.889, T max = 1.000

8982 measured reflections

3053 independent reflections

2944 reflections with I > 2σ(I)

R int = 0.019

Refinement

R[F 2 > 2σ(F 2)] = 0.027

wR(F 2) = 0.070

S = 1.04

3053 reflections

185 parameters

H-atom parameters constrained

Δρmax = 0.21 e Å−3

Δρmin = −0.21 e Å−3

Absolute structure: Flack (1983 ▶), 614 Friedel pairs

Flack parameter: −0.06 (5)

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811039717/im2319sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811039717/im2319Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536811039717/im2319Isup3.cml

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

C15H21ClO4	F(000) = 640
Mr = 300.77	Dx = 1.329 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 8982 reflections
a = 8.0224 (2) Å	θ = 3.6–26.4°
b = 12.1532 (2) Å	µ = 0.26 mm−1
c = 15.4147 (4) Å	T = 180 K
V = 1502.90 (6) Å3	Prism, colourless
Z = 4	0.35 × 0.27 × 0.17 mm

Agilent Xcalibur Eos Gemini ultra diffractometer	3053 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2944 reflections with I > 2σ(I)
graphite	Rint = 0.019
Detector resolution: 16.1978 pixels mm-1	θmax = 26.4°, θmin = 3.6°
ω scans	h = −10→9
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −15→15
Tmin = 0.889, Tmax = 1.000	l = −18→19
8982 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)] = 0.027	H-atom parameters constrained
wR(F2) = 0.070	w = 1/[σ2(Fo2) + (0.0362P)2 + 0.3492P] where P = (Fo2 + 2Fc2)/3
S = 1.04	(Δ/σ)max = 0.001
3053 reflections	Δρmax = 0.21 e Å−3
185 parameters	Δρmin = −0.21 e Å−3
0 restraints	Absolute structure: Flack (1983), 614 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: −0.06 (5)

Experimental. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. CrysAlisPro (Agilent, 2010)

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
Cl	0.47204 (6)	0.42068 (3)	0.58743 (3)	0.03475 (11)
C1	0.60869 (16)	0.59828 (11)	0.36912 (9)	0.0169 (3)
H1	0.6725	0.5379	0.3432	0.020*
C2	0.55399 (17)	0.56590 (10)	0.46192 (9)	0.0169 (3)
H2	0.6465	0.5833	0.5011	0.020*
C3	0.51598 (18)	0.44248 (11)	0.47165 (9)	0.0193 (3)
C4	0.66321 (18)	0.36766 (11)	0.44947 (11)	0.0226 (3)
H4A	0.6774	0.3691	0.3870	0.027*
H4B	0.6322	0.2931	0.4651	0.027*
C5	0.83398 (18)	0.39143 (12)	0.49062 (11)	0.0271 (3)
H5A	0.8208	0.3935	0.5532	0.033*
H5B	0.9085	0.3310	0.4770	0.033*
C6	0.91472 (16)	0.49718 (12)	0.46184 (10)	0.0211 (3)
H6	0.9289	0.5519	0.5034	0.025*
C7	0.96724 (17)	0.51863 (11)	0.38212 (10)	0.0201 (3)
C8	1.01946 (18)	0.63373 (12)	0.35599 (10)	0.0213 (3)
H8	1.1106	0.6281	0.3139	0.026*
C9	0.87577 (18)	0.69698 (12)	0.31401 (10)	0.0231 (3)
H9A	0.8484	0.6619	0.2593	0.028*
H9B	0.9135	0.7711	0.3012	0.028*
C10	0.71583 (16)	0.70436 (11)	0.36933 (10)	0.0181 (3)
H10	0.7458	0.7230	0.4292	0.022*
C11	0.59596 (18)	0.78895 (13)	0.33507 (10)	0.0228 (3)
C12	0.44945 (19)	0.73049 (13)	0.29884 (11)	0.0264 (3)
C13	0.6075 (2)	0.89766 (13)	0.33538 (12)	0.0329 (4)
H13A	0.5217	0.9401	0.3123	0.039*
H13B	0.7013	0.9316	0.3587	0.039*
C14	0.9722 (2)	0.43627 (13)	0.30957 (11)	0.0296 (3)
H14A	0.9579	0.3636	0.3327	0.044*
H14B	1.0777	0.4409	0.2804	0.044*
H14C	0.8842	0.4517	0.2692	0.044*
C15	0.36070 (18)	0.40750 (12)	0.42250 (11)	0.0267 (3)
H15A	0.3759	0.4215	0.3617	0.040*
H15B	0.2666	0.4485	0.4433	0.040*
H15C	0.3415	0.3304	0.4314	0.040*
O1	0.33335 (15)	0.76689 (11)	0.25906 (9)	0.0408 (3)
O2	0.46321 (13)	0.62157 (8)	0.31574 (7)	0.0235 (2)
O3	0.41528 (12)	0.63183 (8)	0.48730 (7)	0.0219 (2)
H3	0.4483	0.6844	0.5159	0.033*
O4	1.07598 (12)	0.69787 (8)	0.42835 (8)	0.0261 (2)
H4	1.1646	0.6730	0.4461	0.039*

	U11	U22	U33	U12	U13	U23
Cl	0.0427 (2)	0.03388 (19)	0.0276 (2)	0.00420 (18)	0.00966 (18)	0.00940 (16)
C1	0.0124 (6)	0.0175 (6)	0.0206 (7)	0.0001 (5)	−0.0032 (5)	0.0002 (5)
C2	0.0130 (6)	0.0169 (6)	0.0208 (7)	0.0019 (5)	0.0001 (5)	−0.0004 (5)
C3	0.0188 (7)	0.0195 (6)	0.0195 (7)	0.0008 (5)	0.0027 (6)	0.0042 (5)
C4	0.0204 (7)	0.0152 (6)	0.0322 (8)	0.0012 (5)	0.0019 (6)	0.0009 (6)
C5	0.0201 (7)	0.0237 (8)	0.0374 (9)	0.0051 (6)	−0.0026 (7)	0.0084 (6)
C6	0.0134 (6)	0.0208 (6)	0.0290 (8)	0.0032 (5)	−0.0038 (6)	−0.0013 (6)
C7	0.0109 (6)	0.0205 (6)	0.0289 (8)	0.0014 (5)	−0.0007 (6)	−0.0065 (6)
C8	0.0150 (7)	0.0231 (7)	0.0257 (7)	−0.0018 (5)	0.0029 (6)	−0.0057 (6)
C9	0.0200 (7)	0.0253 (7)	0.0240 (8)	−0.0045 (6)	0.0034 (6)	0.0022 (6)
C10	0.0155 (6)	0.0179 (6)	0.0208 (7)	−0.0011 (5)	−0.0002 (6)	0.0018 (6)
C11	0.0201 (7)	0.0255 (7)	0.0228 (8)	0.0007 (6)	0.0026 (6)	0.0061 (6)
C12	0.0217 (7)	0.0308 (8)	0.0267 (8)	−0.0005 (6)	0.0007 (7)	0.0100 (6)
C13	0.0331 (9)	0.0247 (8)	0.0408 (10)	0.0031 (7)	0.0023 (8)	0.0073 (7)
C14	0.0240 (8)	0.0288 (8)	0.0361 (9)	−0.0018 (6)	0.0042 (7)	−0.0135 (7)
C15	0.0191 (7)	0.0201 (7)	0.0410 (9)	−0.0039 (6)	−0.0041 (7)	0.0039 (7)
O1	0.0255 (6)	0.0461 (7)	0.0507 (8)	0.0016 (5)	−0.0121 (6)	0.0243 (6)
O2	0.0193 (5)	0.0256 (5)	0.0255 (5)	−0.0039 (4)	−0.0078 (5)	0.0052 (4)
O3	0.0156 (5)	0.0193 (5)	0.0308 (6)	0.0022 (4)	0.0021 (4)	−0.0050 (4)
O4	0.0169 (5)	0.0233 (5)	0.0380 (7)	0.0005 (4)	−0.0052 (4)	−0.0100 (5)

Cl—C3	1.8384 (15)	C8—C9	1.529 (2)
C1—O2	1.4557 (16)	C8—H8	0.9800
C1—C2	1.5471 (19)	C9—C10	1.5433 (19)
C1—C10	1.5495 (18)	C9—H9A	0.9700
C1—H1	0.9800	C9—H9B	0.9700
C2—O3	1.4260 (16)	C10—C11	1.504 (2)
C2—C3	1.5380 (18)	C10—H10	0.9800
C2—H2	0.9800	C11—C13	1.324 (2)
C3—C15	1.519 (2)	C11—C12	1.483 (2)
C3—C4	1.5292 (19)	C12—O1	1.1997 (19)
C4—C5	1.537 (2)	C12—O2	1.3536 (18)
C4—H4A	0.9700	C13—H13A	0.9300
C4—H4B	0.9700	C13—H13B	0.9300
C5—C6	1.506 (2)	C14—H14A	0.9600
C5—H5A	0.9700	C14—H14B	0.9600
C5—H5B	0.9700	C14—H14C	0.9600
C6—C7	1.325 (2)	C15—H15A	0.9600
C6—H6	0.9300	C15—H15B	0.9600
C7—C14	1.5014 (19)	C15—H15C	0.9600
C7—C8	1.5148 (19)	O3—H3	0.8200
C8—O4	1.4343 (17)	O4—H4	0.8200
O2—C1—C2	110.16 (11)	O4—C8—H8	108.5
O2—C1—C10	106.51 (10)	C7—C8—H8	108.5
C2—C1—C10	111.53 (11)	C9—C8—H8	108.5
O2—C1—H1	109.5	C8—C9—C10	114.96 (12)
C2—C1—H1	109.5	C8—C9—H9A	108.5
C10—C1—H1	109.5	C10—C9—H9A	108.5
O3—C2—C3	111.50 (11)	C8—C9—H9B	108.5
O3—C2—C1	109.40 (11)	C10—C9—H9B	108.5
C3—C2—C1	113.23 (11)	H9A—C9—H9B	107.5
O3—C2—H2	107.5	C11—C10—C9	112.17 (12)
C3—C2—H2	107.5	C11—C10—C1	102.32 (11)
C1—C2—H2	107.5	C9—C10—C1	114.31 (12)
C15—C3—C4	110.83 (12)	C11—C10—H10	109.3
C15—C3—C2	112.77 (11)	C9—C10—H10	109.3
C4—C3—C2	113.89 (11)	C1—C10—H10	109.3
C15—C3—Cl	106.66 (10)	C13—C11—C12	122.32 (15)
C4—C3—Cl	106.23 (10)	C13—C11—C10	129.51 (15)
C2—C3—Cl	105.86 (9)	C12—C11—C10	108.16 (13)
C3—C4—C5	118.97 (12)	O1—C12—O2	121.48 (15)
C3—C4—H4A	107.6	O1—C12—C11	129.15 (15)
C5—C4—H4A	107.6	O2—C12—C11	109.36 (13)
C3—C4—H4B	107.6	C11—C13—H13A	120.0
C5—C4—H4B	107.6	C11—C13—H13B	120.0
H4A—C4—H4B	107.0	H13A—C13—H13B	120.0
C6—C5—C4	114.97 (12)	C7—C14—H14A	109.5
C6—C5—H5A	108.5	C7—C14—H14B	109.5
C4—C5—H5A	108.5	H14A—C14—H14B	109.5
C6—C5—H5B	108.5	C7—C14—H14C	109.5
C4—C5—H5B	108.5	H14A—C14—H14C	109.5
H5A—C5—H5B	107.5	H14B—C14—H14C	109.5
C7—C6—C5	125.30 (14)	C3—C15—H15A	109.5
C7—C6—H6	117.3	C3—C15—H15B	109.5
C5—C6—H6	117.3	H15A—C15—H15B	109.5
C6—C7—C14	124.62 (13)	C3—C15—H15C	109.5
C6—C7—C8	121.08 (13)	H15A—C15—H15C	109.5
C14—C7—C8	114.22 (12)	H15B—C15—H15C	109.5
O4—C8—C7	112.49 (12)	C12—O2—C1	111.36 (11)
O4—C8—C9	107.12 (11)	C2—O3—H3	109.5
C7—C8—C9	111.61 (12)	C8—O4—H4	109.5

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O4i	0.82	1.96	2.763 (1)	167
O4—H4···O3ii	0.82	2.17	2.980 (1)	171

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3⋯O4i	0.82	1.96	2.763 (1)	167
O4—H4⋯O3ii	0.82	2.17	2.980 (1)	171

Symmetry codes: (i) ; (ii) .