Redetermination and absolute configuration of 6-hydroxy­salvinolone

Fun, H.-K.; Quah, C.K.; Chantrapromma, S.

doi:10.1107/S1600536809053197

organic compounds

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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Pages o146-o147

doi:10.1107/S1600536809053197

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Redetermination and absolute configuration of 6-hydroxysalvinolone

Hoong-Kun Fun,^a ^*‡ Ching Kheng Quah ^a § and Suchada Chantrapromma ^b ¶

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and ^bCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
^*Correspondence e-mail: hkfun@usm.my

(Received 8 December 2009; accepted 10 December 2009; online 16 December 2009)

The crystal structure of the title compound [systematic name: 5,6,10-trihydroxy-7-isopropyl-1,1,4a-trimethyl-2,3,4,4a-tetrahydrophenanthren-9(1H)-one], C₂₀H₂₆O₄, has been reported previously [Salae et al. (2009 ). Acta Cryst. E65, o2379–o2380], but the absolute configuration could not be determined as there was no significant anomalous dispersion using data collected with Mo radiation. The absolute configuration has now been determined by refinement of the Flack parameter with data collected using Cu radiation. The absolute configuration at position 4a of the diterpenoid is (R)-methyl; other features of the molecule and its crystal packing are similar to those previously described.

Related literature

For background to diterpenes, see: Fraga et al. (2005 ); Hueso-Rodríguez et al. (1983 ) and Topcu & Ulubelen (1996 ). For the previous determination, see: Salae et al. (2009). For bond-length data, see: Allen et al. (1987 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For puckering parameters, see: Cremer & Pople (1975 ). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986 ).

Experimental

Crystal data

C₂₀H₂₆O₄
M_r = 330.41
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.4908 (1) Å
b = 13.1684 (2) Å
c = 13.8105 (2) Å
V = 1726.02 (4) Å³
Z = 4
Cu Kα radiation
μ = 0.70 mm⁻¹
T = 100 K
0.35 × 0.30 × 0.27 mm

Data collection

Bruker APEX Duo CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.790, T_max = 0.835
6410 measured reflections
2622 independent reflections
2581 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.089
S = 1.09
2622 reflections
317 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.22 e Å⁻³
Absolute structure: Flack (1983 ), 1609 Friedel pairs
Flack parameter: 0.06 (17)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O1⋯O2	0.87 (2)	1.93 (2)	2.5607 (14)	128 (2)
O3—H1O3⋯O2ⁱ	0.85 (3)	1.87 (3)	2.6988 (14)	167 (2)
O4—H1O4⋯O3	0.81 (3)	2.04 (3)	2.5690 (14)	123 (2)
C14—H14A⋯O3ⁱⁱ	0.975 (17)	2.542 (17)	3.4774 (17)	160.8 (14)
C15—H15A⋯O2ⁱ	0.98	2.45	3.1933 (17)	132
C18—H18B⋯O1	1.005 (18)	2.524 (18)	3.1335 (19)	118.7 (13)
C19—H19A⋯O1	0.971 (19)	2.273 (19)	2.903 (2)	121.7 (14)
C20—H20C⋯O4	1.01 (2)	2.403 (19)	3.0779 (18)	123.9 (14)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+1, z+{\script{1\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, -y+1, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809053197/sj2711sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809053197/sj2711Isup2.hkl

checkCIF report

Comment top

The title diterpenoid compound (I) known as 6-hydroxysalvinolone (Topcu & Ulubelen, 1996) or 14-deoxycoleon U (Fraga et al., 2005; Hueso-Rodríguez et al., 1983), was isolated from the roots of Premna obtusifolia, a Thai manglove plant which was collected from Satun province in the Southern part of Thailand. Its crystal structure has been reported (Salae et al., 2009) but the absolute configuration could not be determined due to no large anomalous dispersion using a data set collected with Mo radiation. Data on the same sample was recollected using Cu radiation with our newly-installed Bruker Apex-Duo CCD diffractometer and the absolute configuration at atom C10 (or the 4a position) was determined as (R)-methyl making use of the large anomalous scattering of Cu Kα X-radiation with the Flack parameter being refined to 0.06 (17). We report herein the crystal structure of (I) determined from the Cu data.

Fig. 1 shows the molecular structure of (I); the ring conformations, bond lengths and angles are almost identical to those previously described (Salae et al., 2009).

Fig. 2 shows the crystal packing of (I), intermolecular O—H···O hydrogen bonds and weak C—H···O interactions (Table 1) linked the molecules into infinite one dimensional screw chains along the [0 0 1] direction. This feature and also the O—H···O hydrogen bonds and weak C—H···O interactions are also similar to those in the previous report by Salae et al. (2009).

Related literature top

For background to diterpenes, see: Fraga et al. (2005); Hueso-Rodríguez et al. (1983) and Topcu et al. (1996). For the previous determination, see: Salae et al. (2009). For bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering parameters, see: Cremer & Pople (1975). For the stability of the temperature controller used in the data collection, see Cosier & Glazer, (1986).

Experimental top

The compound was isolated and the crystal grown as reported by Salae et al. (2009).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids and the atom-numbering scheme. Intramolecular hydrogen bonds are shown as dashed lines.
	Fig. 2. The crystal packing of (I) viewed along the a axis, showing screw chains along the [0 0 1] direction. Hydrogen bonds are shown as dashed lines.

5,6,10-trihydroxy-7-isopropyl-1,1,4a-trimethyl-2,3,4,4a-tetrahydrophenanthren- 9(1H)-one top

Crystal data top

C₂₀H₂₆O₄	F(000) = 712
M_r = 330.41	D_x = 1.271 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2ac 2ab	Cell parameters from 2622 reflections
a = 9.4908 (1) Å	θ = 5.7–62.5°
b = 13.1684 (2) Å	µ = 0.70 mm⁻¹
c = 13.8105 (2) Å	T = 100 K
V = 1726.02 (4) Å³	Block, colorless
Z = 4	0.35 × 0.30 × 0.27 mm

Data collection top

Bruker APEX Duo CCD area-detector diffractometer	2622 independent reflections
Radiation source: sealed tube	2581 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ϕ and ω scans	θ_max = 62.5°, θ_min = 5.7°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −10→10
T_min = 0.790, T_max = 0.835	k = −15→15
6410 measured reflections	l = −15→11

Refinement top

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)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.089	w = 1/[σ²(F_o²) + (0.062P)² + 0.1924P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max = 0.001
2622 reflections	Δρ_max = 0.22 e Å⁻³
317 parameters	Δρ_min = −0.22 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1609 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.06 (17)

Crystal data top

C₂₀H₂₆O₄	V = 1726.02 (4) Å³
M_r = 330.41	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 9.4908 (1) Å	µ = 0.70 mm⁻¹
b = 13.1684 (2) Å	T = 100 K
c = 13.8105 (2) Å	0.35 × 0.30 × 0.27 mm

Data collection top

Bruker APEX Duo CCD area-detector diffractometer	2622 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2581 reflections with I > 2σ(I)
T_min = 0.790, T_max = 0.835	R_int = 0.023
6410 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.089	Δρ_max = 0.22 e Å⁻³
S = 1.09	Δρ_min = −0.22 e Å⁻³
2622 reflections	Absolute structure: Flack (1983), 1609 Friedel pairs
317 parameters	Absolute structure parameter: 0.06 (17)
0 restraints

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.26498 (14)	0.14479 (8)	0.64508 (8)	0.0226 (3)
H1O1	0.266 (3)	0.2024 (19)	0.6146 (17)	0.045 (6)*
O2	0.25865 (15)	0.33763 (7)	0.66855 (7)	0.0248 (3)
O3	0.24268 (12)	0.46642 (8)	1.11130 (7)	0.0158 (2)
H1O3	0.247 (3)	0.530 (2)	1.1204 (17)	0.048 (6)*
O4	0.25736 (13)	0.27211 (7)	1.09810 (8)	0.0182 (3)
H1O4	0.257 (3)	0.3146 (19)	1.1402 (19)	0.049 (7)*
C1	0.14780 (17)	0.11004 (11)	0.98596 (11)	0.0173 (3)
H1A	0.188 (2)	0.1027 (15)	1.0541 (15)	0.028 (5)*
H1B	0.068 (2)	0.1522 (15)	0.9886 (15)	0.026 (5)*
C2	0.09572 (16)	0.00499 (11)	0.95493 (11)	0.0183 (3)
H2A	0.065 (2)	−0.0370 (17)	1.0113 (16)	0.034 (5)*
H2B	0.013 (2)	0.0121 (13)	0.9127 (14)	0.023 (4)*
C3	0.20793 (16)	−0.05336 (11)	0.89923 (11)	0.0161 (3)
H3A	0.1764 (18)	−0.1257 (14)	0.8862 (12)	0.016 (4)*
H3B	0.291 (2)	−0.0611 (15)	0.9379 (15)	0.026 (5)*
C4	0.24229 (18)	−0.00042 (10)	0.80241 (10)	0.0157 (3)
C5	0.24927 (16)	0.11556 (10)	0.81588 (11)	0.0134 (3)
C6	0.25717 (17)	0.17835 (11)	0.73906 (10)	0.0166 (3)
C7	0.25656 (17)	0.28940 (11)	0.74620 (10)	0.0165 (3)
C8	0.25203 (16)	0.33638 (10)	0.84151 (10)	0.0137 (3)
C9	0.25196 (14)	0.27429 (10)	0.92394 (10)	0.0125 (3)
C10	0.26072 (15)	0.15823 (10)	0.91813 (10)	0.0134 (3)
C11	0.25250 (15)	0.32477 (11)	1.01271 (10)	0.0128 (3)
C12	0.24735 (15)	0.43145 (11)	1.01817 (9)	0.0127 (3)
C13	0.24955 (15)	0.49239 (10)	0.93545 (10)	0.0134 (3)
C14	0.25173 (16)	0.44233 (10)	0.84755 (10)	0.0144 (3)
H14A	0.257 (2)	0.4837 (13)	0.7891 (12)	0.017 (4)*
C15	0.24936 (17)	0.60773 (10)	0.94334 (10)	0.0157 (3)
H15A	0.3062	0.6260	1.0000	0.019*
C16	0.3152 (2)	0.65897 (12)	0.85566 (14)	0.0298 (4)
H16A	0.412 (2)	0.6255 (18)	0.8398 (18)	0.050 (7)*
H16B	0.3240 (19)	0.7331 (16)	0.8679 (15)	0.029 (5)*
H16C	0.255 (2)	0.6499 (16)	0.8008 (16)	0.036 (5)*
C17	0.09970 (16)	0.64673 (11)	0.96111 (13)	0.0218 (4)
H17A	0.059 (2)	0.6171 (15)	1.0234 (16)	0.030 (5)*
H17B	0.039 (2)	0.6260 (16)	0.9072 (16)	0.034 (5)*
H17C	0.0999 (18)	0.7216 (14)	0.9708 (13)	0.021 (4)*
C18	0.38294 (17)	−0.04049 (11)	0.76212 (12)	0.0187 (3)
H18A	0.461 (2)	−0.0244 (14)	0.8056 (14)	0.023 (4)*
H18B	0.4045 (19)	−0.0088 (14)	0.6976 (13)	0.021 (4)*
H18C	0.3732 (19)	−0.1131 (16)	0.7533 (14)	0.024 (5)*
C19	0.12291 (17)	−0.02847 (12)	0.73087 (12)	0.0210 (4)
H19A	0.138 (2)	0.0003 (14)	0.6670 (14)	0.026 (5)*
H19B	0.028 (2)	−0.0059 (14)	0.7535 (15)	0.029 (5)*
H19C	0.1167 (18)	−0.1038 (14)	0.7267 (13)	0.017 (4)*
C20	0.41254 (15)	0.13291 (11)	0.95429 (11)	0.0159 (3)
H20A	0.481 (2)	0.1651 (14)	0.9128 (15)	0.026 (5)*
H20B	0.4291 (18)	0.0620 (15)	0.9528 (13)	0.021 (4)*
H20C	0.425 (2)	0.1618 (14)	1.0211 (15)	0.028 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0463 (7)	0.0115 (5)	0.0101 (5)	0.0010 (5)	0.0012 (5)	−0.0010 (4)
O2	0.0506 (7)	0.0120 (5)	0.0117 (5)	0.0003 (5)	0.0000 (5)	0.0024 (4)
O3	0.0281 (6)	0.0087 (5)	0.0106 (5)	−0.0025 (5)	0.0021 (4)	−0.0030 (4)
O4	0.0331 (6)	0.0110 (5)	0.0104 (5)	−0.0001 (5)	−0.0017 (5)	0.0004 (4)
C1	0.0216 (8)	0.0100 (7)	0.0203 (8)	0.0003 (6)	0.0057 (6)	0.0015 (6)
C2	0.0203 (8)	0.0157 (7)	0.0187 (7)	−0.0018 (6)	0.0050 (6)	0.0034 (6)
C3	0.0206 (7)	0.0095 (7)	0.0181 (8)	−0.0006 (5)	−0.0007 (6)	−0.0005 (6)
C4	0.0212 (7)	0.0117 (7)	0.0143 (7)	0.0001 (6)	0.0000 (6)	−0.0013 (5)
C5	0.0139 (7)	0.0109 (7)	0.0154 (7)	0.0012 (6)	−0.0008 (6)	−0.0002 (5)
C6	0.0239 (8)	0.0129 (7)	0.0129 (7)	0.0011 (6)	0.0004 (6)	−0.0022 (5)
C7	0.0248 (8)	0.0121 (7)	0.0125 (7)	−0.0001 (7)	−0.0012 (6)	0.0014 (5)
C8	0.0156 (7)	0.0135 (7)	0.0122 (7)	−0.0001 (6)	−0.0005 (6)	0.0002 (5)
C9	0.0111 (7)	0.0120 (7)	0.0142 (7)	0.0002 (5)	−0.0012 (6)	0.0005 (5)
C10	0.0165 (7)	0.0119 (7)	0.0120 (7)	0.0009 (6)	0.0016 (6)	0.0005 (6)
C11	0.0145 (7)	0.0114 (7)	0.0124 (7)	−0.0001 (6)	0.0004 (6)	0.0013 (5)
C12	0.0143 (7)	0.0130 (7)	0.0109 (7)	−0.0011 (6)	−0.0001 (6)	−0.0021 (5)
C13	0.0136 (6)	0.0110 (7)	0.0156 (7)	−0.0003 (6)	0.0011 (6)	0.0015 (5)
C14	0.0193 (7)	0.0112 (6)	0.0127 (7)	0.0005 (6)	0.0004 (6)	0.0014 (6)
C15	0.0245 (8)	0.0087 (7)	0.0139 (7)	−0.0007 (6)	−0.0013 (6)	−0.0016 (5)
C16	0.0545 (12)	0.0102 (8)	0.0247 (9)	0.0006 (8)	0.0132 (9)	−0.0004 (7)
C17	0.0255 (8)	0.0122 (7)	0.0277 (9)	0.0021 (7)	−0.0027 (7)	−0.0010 (7)
C18	0.0243 (8)	0.0116 (7)	0.0200 (8)	0.0024 (6)	0.0030 (7)	0.0005 (6)
C19	0.0273 (9)	0.0148 (8)	0.0208 (8)	−0.0025 (7)	−0.0050 (7)	−0.0025 (6)
C20	0.0194 (7)	0.0106 (7)	0.0177 (7)	0.0018 (6)	−0.0036 (6)	−0.0010 (6)

Geometric parameters (Å, º) top

O1—C6	1.3732 (17)	C9—C11	1.394 (2)
O1—H1O1	0.87 (3)	C9—C10	1.5327 (18)
O2—C7	1.2465 (18)	C10—C20	1.561 (2)
O3—C12	1.3669 (16)	C11—C12	1.408 (2)
O3—H1O3	0.85 (3)	C12—C13	1.3962 (19)
O4—C11	1.3688 (16)	C13—C14	1.381 (2)
O4—H1O4	0.81 (3)	C13—C15	1.5228 (17)
C1—C2	1.530 (2)	C14—H14A	0.975 (18)
C1—C10	1.558 (2)	C15—C16	1.520 (2)
C1—H1A	1.02 (2)	C15—C17	1.530 (2)
C1—H1B	0.94 (2)	C15—H15A	0.9800
C2—C3	1.522 (2)	C16—H16A	1.04 (2)
C2—H2A	1.00 (2)	C16—H16B	0.99 (2)
C2—H2B	0.99 (2)	C16—H16C	0.96 (2)
C3—C4	1.543 (2)	C17—H17A	1.02 (2)
C3—H3A	1.014 (19)	C17—H17B	0.98 (2)
C3—H3B	0.96 (2)	C17—H17C	0.996 (18)
C4—C18	1.540 (2)	C18—H18A	0.98 (2)
C4—C5	1.5399 (18)	C18—H18B	1.005 (19)
C4—C19	1.548 (2)	C18—H18C	0.97 (2)
C5—C6	1.347 (2)	C19—H19A	0.970 (19)
C5—C10	1.5236 (19)	C19—H19B	1.00 (2)
C6—C7	1.4656 (19)	C19—H19C	0.995 (18)
C7—C8	1.455 (2)	C20—H20A	0.97 (2)
C8—C14	1.3978 (19)	C20—H20B	0.947 (19)
C8—C9	1.4016 (19)	C20—H20C	1.00 (2)

C6—O1—H1O1	100.3 (15)	O4—C11—C9	121.07 (12)
C12—O3—H1O3	118.0 (16)	O4—C11—C12	117.42 (12)
C11—O4—H1O4	105.7 (17)	C9—C11—C12	121.51 (12)
C2—C1—C10	114.96 (12)	O3—C12—C13	125.22 (12)
C2—C1—H1A	107.1 (11)	O3—C12—C11	112.81 (12)
C10—C1—H1A	109.4 (11)	C13—C12—C11	121.96 (12)
C2—C1—H1B	106.5 (12)	C14—C13—C12	116.42 (13)
C10—C1—H1B	109.7 (12)	C14—C13—C15	122.60 (13)
H1A—C1—H1B	108.9 (17)	C12—C13—C15	120.98 (12)
C3—C2—C1	111.83 (12)	C13—C14—C8	121.92 (13)
C3—C2—H2A	108.6 (12)	C13—C14—H14A	117.5 (10)
C1—C2—H2A	112.2 (12)	C8—C14—H14A	120.6 (10)
C3—C2—H2B	108.0 (10)	C16—C15—C13	112.65 (12)
C1—C2—H2B	109.8 (11)	C16—C15—C17	111.12 (14)
H2A—C2—H2B	106.2 (16)	C13—C15—C17	110.32 (13)
C2—C3—C4	110.96 (12)	C16—C15—H15A	107.5
C2—C3—H3A	111.0 (10)	C13—C15—H15A	107.5
C4—C3—H3A	109.4 (10)	C17—C15—H15A	107.5
C2—C3—H3B	110.3 (12)	C15—C16—H16A	110.0 (13)
C4—C3—H3B	110.9 (12)	C15—C16—H16B	109.6 (12)
H3A—C3—H3B	104.0 (15)	H16A—C16—H16B	112.1 (16)
C18—C4—C5	110.26 (13)	C15—C16—H16C	109.2 (13)
C18—C4—C3	109.98 (12)	H16A—C16—H16C	108.0 (18)
C5—C4—C3	110.64 (12)	H16B—C16—H16C	107.9 (17)
C18—C4—C19	108.79 (12)	C15—C17—H17A	110.9 (11)
C5—C4—C19	110.20 (12)	C15—C17—H17B	109.4 (12)
C3—C4—C19	106.89 (12)	H17A—C17—H17B	108.1 (16)
C6—C5—C10	119.96 (12)	C15—C17—H17C	110.6 (10)
C6—C5—C4	121.06 (13)	H17A—C17—H17C	105.5 (15)
C10—C5—C4	118.74 (12)	H17B—C17—H17C	112.2 (16)
C5—C6—O1	123.36 (13)	C4—C18—H18A	111.3 (11)
C5—C6—C7	124.01 (13)	C4—C18—H18B	110.8 (10)
O1—C6—C7	112.63 (12)	H18A—C18—H18B	107.4 (15)
O2—C7—C8	124.20 (12)	C4—C18—H18C	107.5 (11)
O2—C7—C6	116.78 (12)	H18A—C18—H18C	111.3 (16)
C8—C7—C6	119.02 (12)	H18B—C18—H18C	108.5 (16)
C14—C8—C9	122.27 (12)	C4—C19—H19A	112.3 (11)
C14—C8—C7	118.58 (12)	C4—C19—H19B	113.0 (12)
C9—C8—C7	119.13 (12)	H19A—C19—H19B	107.5 (16)
C11—C9—C8	115.85 (12)	C4—C19—H19C	108.5 (10)
C11—C9—C10	121.41 (12)	H19A—C19—H19C	110.1 (15)
C8—C9—C10	122.62 (12)	H19B—C19—H19C	105.1 (14)
C5—C10—C9	114.36 (11)	C10—C20—H20A	109.9 (11)
C5—C10—C1	110.97 (12)	C10—C20—H20B	110.9 (11)
C9—C10—C1	109.71 (12)	H20A—C20—H20B	107.8 (15)
C5—C10—C20	106.47 (12)	C10—C20—H20C	108.6 (11)
C9—C10—C20	104.26 (12)	H20A—C20—H20C	107.5 (16)
C1—C10—C20	110.82 (11)	H20B—C20—H20C	112.0 (16)

C10—C1—C2—C3	28.97 (17)	C6—C5—C10—C20	−103.23 (16)
C1—C2—C3—C4	−64.94 (16)	C4—C5—C10—C20	71.28 (16)
C2—C3—C4—C18	163.23 (12)	C11—C9—C10—C5	176.24 (12)
C2—C3—C4—C5	41.17 (16)	C8—C9—C10—C5	−7.9 (2)
C2—C3—C4—C19	−78.83 (15)	C11—C9—C10—C1	50.82 (18)
C18—C4—C5—C6	67.99 (19)	C8—C9—C10—C1	−133.35 (13)
C3—C4—C5—C6	−170.13 (14)	C11—C9—C10—C20	−67.90 (16)
C19—C4—C5—C6	−52.1 (2)	C8—C9—C10—C20	107.93 (15)
C18—C4—C5—C10	−106.46 (15)	C2—C1—C10—C5	25.05 (17)
C3—C4—C5—C10	15.42 (19)	C2—C1—C10—C9	152.39 (13)
C19—C4—C5—C10	133.43 (14)	C2—C1—C10—C20	−93.02 (15)
C10—C5—C6—O1	171.82 (14)	C8—C9—C11—O4	−177.74 (13)
C4—C5—C6—O1	−2.6 (2)	C10—C9—C11—O4	−1.6 (2)
C10—C5—C6—C7	−9.0 (2)	C8—C9—C11—C12	2.6 (2)
C4—C5—C6—C7	176.61 (15)	C10—C9—C11—C12	178.69 (13)
C5—C6—C7—O2	−177.13 (14)	O4—C11—C12—O3	−2.3 (2)
O1—C6—C7—O2	2.1 (2)	C9—C11—C12—O3	177.35 (13)
C5—C6—C7—C8	2.2 (3)	O4—C11—C12—C13	176.60 (12)
O1—C6—C7—C8	−178.55 (12)	C9—C11—C12—C13	−3.7 (2)
O2—C7—C8—C14	−0.8 (2)	O3—C12—C13—C14	−178.86 (14)
C6—C7—C8—C14	179.89 (14)	C11—C12—C13—C14	2.3 (2)
O2—C7—C8—C9	−179.14 (16)	O3—C12—C13—C15	1.1 (2)
C6—C7—C8—C9	1.6 (2)	C11—C12—C13—C15	−177.71 (13)
C14—C8—C9—C11	−0.4 (2)	C12—C13—C14—C8	−0.1 (2)
C7—C8—C9—C11	177.83 (14)	C15—C13—C14—C8	179.93 (14)
C14—C8—C9—C10	−176.45 (13)	C9—C8—C14—C13	−0.8 (2)
C7—C8—C9—C10	1.8 (2)	C7—C8—C14—C13	−179.08 (14)
C6—C5—C10—C9	11.3 (2)	C14—C13—C15—C16	−25.5 (2)
C4—C5—C10—C9	−174.14 (12)	C12—C13—C15—C16	154.57 (15)
C6—C5—C10—C1	136.09 (15)	C14—C13—C15—C17	99.31 (17)
C4—C5—C10—C1	−49.39 (18)	C12—C13—C15—C17	−80.62 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O2	0.87 (2)	1.93 (2)	2.5607 (14)	128 (2)
O3—H1O3···O2ⁱ	0.85 (3)	1.87 (3)	2.6988 (14)	167 (2)
O4—H1O4···O3	0.81 (3)	2.04 (3)	2.5690 (14)	123 (2)
C14—H14A···O3ⁱⁱ	0.975 (17)	2.542 (17)	3.4774 (17)	160.8 (14)
C15—H15A···O2ⁱ	0.98	2.45	3.1933 (17)	132
C18—H18B···O1	1.005 (18)	2.524 (18)	3.1335 (19)	118.7 (13)
C19—H19A···O1	0.971 (19)	2.273 (19)	2.903 (2)	121.7 (14)
C20—H20C···O4	1.01 (2)	2.403 (19)	3.0779 (18)	123.9 (14)

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

Experimental details

Crystal data
Chemical formula	C₂₀H₂₆O₄
M_r	330.41
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	9.4908 (1), 13.1684 (2), 13.8105 (2)
V (Å³)	1726.02 (4)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	0.70
Crystal size (mm)	0.35 × 0.30 × 0.27

Data collection
Diffractometer	Bruker APEX Duo CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.790, 0.835
No. of measured, independent and observed [I > 2σ(I)] reflections	6410, 2622, 2581
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.575

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.089, 1.09
No. of reflections	2622
No. of parameters	317
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.22
Absolute structure	Flack (1983), 1609 Friedel pairs
Absolute structure parameter	0.06 (17)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O2	0.87 (2)	1.93 (2)	2.5607 (14)	128 (2)
O3—H1O3···O2ⁱ	0.85 (3)	1.87 (3)	2.6988 (14)	167 (2)
O4—H1O4···O3	0.81 (3)	2.04 (3)	2.5690 (14)	123 (2)
C14—H14A···O3ⁱⁱ	0.975 (17)	2.542 (17)	3.4774 (17)	160.8 (14)
C15—H15A···O2ⁱ	0.98	2.45	3.1933 (17)	132
C18—H18B···O1	1.005 (18)	2.524 (18)	3.1335 (19)	118.7 (13)
C19—H19A···O1	0.971 (19)	2.273 (19)	2.903 (2)	121.7 (14)
C20—H20C···O4	1.01 (2)	2.403 (19)	3.0779 (18)	123.9 (14)

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: A-5525-2009.

¶Thomson Reuters ResearcherID: A-5085-2009. Additional correspondence author, email: suchada.c@psu.ac.th

Acknowledgements

The authors thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. Mr Abdul Wahab Salae is acknowledged for supplying the sample of 6-hydroxysalvinolone.

References

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