(1S*,2S*,5S*,9S*,10S*,11R*,18R*)-9,10,18-Trihydr­oxy-12,12-dimethyl-6-methyl­ene-17-oxapenta­cyclo­[7.6.2.1^5,8.0^1,11.0^2,8]octa­decane-7,15-dione

The title compound, C₂₀H₂₆O₆, was prepared from the natural diterpenoid oridonin and is composed of one five-membered ring with an envelope conformation and five six-membered rings, four with boat conformations and one with a twist-boat conformation. The mol­ecules are assembled into chains via hydrogen bonding.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.096
• Data-to-parameter ratio = 8.1

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.778     1.000
            Tmin(prime) and Tmax expected:      0.948     0.980
            RR(prime) =      0.805
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.80
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.98
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.61 Ratio

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           27.00
           From the CIF: _reflns_number_total               2029
           Count of symmetry unique reflns         2040
           Completeness (_total/calc)             99.46%
           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
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C1     = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C2     = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C5     = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C9     = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C10    = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C11    = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C18    = .          R

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

   9 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
   2 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

Computing details

Data collection: SMART (Bruker, 1999); 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: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

(1S*,2S*,5S*,9S*,10S*,11R*,18R*)-9,10,18-trihydroxy-12,12-dimethyl-6-methylene- 17-oxapentacyclo[7.6.2.1^5,8.0^1,11.0^2,8]octadecane-7,15-dione

Crystal data

C20H26O6	F(000) = 388
Mr = 362.41	Dx = 1.407 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 10.8260 (11) Å	Cell parameters from 2542 reflections
b = 6.5434 (7) Å	θ = 6.2–56.3°
c = 13.0040 (13) Å	µ = 0.10 mm^−1
β = 111.774 (2)°	T = 293 K
V = 855.47 (15) Å^3	Prism, colorless
Z = 2	0.51 × 0.42 × 0.19 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2029 independent reflections
Radiation source: fine-focus sealed tube	1850 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
φ and ω scans	θmax = 27.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −13→11
Tmin = 0.778, Tmax = 1.000	k = −8→8
5077 measured reflections	l = −16→14

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0631P)^2] where P = (Fo^2 + 2Fc^2)/3
2029 reflections	(Δ/σ)max < 0.001
249 parameters	Δρmax = 0.25 e Å^−3
2 restraints	Δρmin = −0.17 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
O1	0.35045 (19)	0.5132 (4)	0.91189 (14)	0.0535 (5)
C1	0.4402 (2)	0.6195 (4)	0.77760 (16)	0.0265 (4)
O2	0.72904 (16)	0.5751 (3)	0.63154 (12)	0.0423 (5)
C2	0.5865 (2)	0.5424 (4)	0.81519 (17)	0.0279 (5)
H2	0.5866	0.4201	0.7717	0.033*
O3	0.63809 (15)	1.0273 (3)	0.67878 (13)	0.0334 (4)
H3	0.599 (3)	1.070 (6)	0.610 (2)	0.064 (10)*
C3	0.6490 (2)	0.4839 (5)	0.93790 (19)	0.0402 (6)
H3A	0.6275	0.5883	0.9816	0.048*
H3B	0.6103	0.3563	0.9493	0.048*
O4	0.48934 (17)	0.7334 (3)	0.51946 (11)	0.0326 (4)
H4	0.571 (3)	0.686 (4)	0.5514 (19)	0.032 (7)*
C4	0.8001 (2)	0.4600 (5)	0.97903 (19)	0.0420 (6)
H4A	0.8213	0.3236	0.9613	0.050*
H4B	0.8371	0.4748	1.0589	0.050*
O5	0.50762 (15)	0.9747 (2)	0.77663 (12)	0.0308 (4)
C5	0.8649 (2)	0.6178 (4)	0.92732 (18)	0.0355 (5)
H5	0.9524	0.6584	0.9804	0.043*
O6	0.85135 (18)	0.9579 (3)	0.86170 (16)	0.0482 (5)
H6	0.802 (3)	1.010 (6)	0.803 (2)	0.077 (12)*
C6	0.8753 (2)	0.5405 (4)	0.8220 (2)	0.0375 (6)
C7	0.7536 (2)	0.6063 (4)	0.72898 (17)	0.0300 (5)
C8	0.6659 (2)	0.7158 (3)	0.78031 (16)	0.0252 (4)
C9	0.5676 (2)	0.8765 (3)	0.70816 (15)	0.0248 (4)
C10	0.4503 (2)	0.7925 (4)	0.60920 (16)	0.0259 (4)
H10	0.3847	0.9025	0.5823	0.031*
C11	0.38428 (19)	0.6178 (4)	0.64942 (16)	0.0251 (4)
H11	0.4183	0.4917	0.6289	0.030*
C12	0.2305 (2)	0.6004 (4)	0.59544 (18)	0.0316 (5)
C13	0.1946 (3)	0.3890 (5)	0.6279 (2)	0.0428 (6)
H13A	0.1023	0.3913	0.6209	0.051*
H13B	0.2024	0.2892	0.5754	0.051*
C14	0.2798 (3)	0.3171 (4)	0.7453 (2)	0.0433 (6)
H14A	0.2224	0.2514	0.7775	0.052*
H14B	0.3426	0.2155	0.7403	0.052*
C15	0.3552 (2)	0.4841 (4)	0.82104 (19)	0.0337 (5)
C16	0.4451 (2)	0.8340 (4)	0.82587 (18)	0.0304 (5)
H16A	0.3554	0.8800	0.8129	0.036*
H16B	0.4941	0.8299	0.9052	0.036*
C18	0.7751 (2)	0.8042 (4)	0.88621 (17)	0.0338 (5)
H18	0.7380	0.8506	0.9404	0.041*
C19	0.9715 (3)	0.4382 (6)	0.8068 (2)	0.0645 (10)
H19A	0.9649	0.4042	0.7355	0.077*
H19B	1.0463	0.3998	0.8673	0.077*
C20	0.1847 (2)	0.6066 (5)	0.47021 (19)	0.0441 (6)
H20A	0.0909	0.5802	0.4381	0.066*
H20B	0.2315	0.5046	0.4459	0.066*
H20C	0.2028	0.7392	0.4474	0.066*
C21	0.1571 (3)	0.7647 (5)	0.6337 (2)	0.0469 (7)
H21A	0.1855	0.8973	0.6199	0.070*
H21B	0.1765	0.7493	0.7116	0.070*
H21C	0.0631	0.7509	0.5939	0.070*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0613 (12)	0.0685 (14)	0.0417 (10)	−0.0013 (11)	0.0320 (9)	0.0087 (10)
C1	0.0266 (10)	0.0285 (11)	0.0256 (10)	0.0040 (9)	0.0113 (8)	0.0047 (9)
O2	0.0388 (9)	0.0593 (13)	0.0285 (8)	0.0074 (9)	0.0121 (7)	−0.0088 (8)
C2	0.0286 (10)	0.0282 (11)	0.0265 (10)	0.0048 (9)	0.0097 (8)	0.0043 (9)
O3	0.0318 (8)	0.0343 (9)	0.0280 (8)	−0.0075 (7)	0.0041 (6)	0.0063 (7)
C3	0.0384 (13)	0.0490 (15)	0.0338 (12)	0.0097 (11)	0.0143 (10)	0.0154 (11)
O4	0.0320 (8)	0.0455 (10)	0.0196 (8)	−0.0027 (8)	0.0086 (6)	−0.0027 (7)
C4	0.0385 (13)	0.0513 (16)	0.0319 (12)	0.0107 (12)	0.0080 (10)	0.0130 (11)
O5	0.0373 (8)	0.0265 (8)	0.0299 (8)	0.0047 (7)	0.0141 (7)	−0.0020 (6)
C5	0.0264 (11)	0.0456 (14)	0.0281 (11)	0.0031 (11)	0.0026 (9)	−0.0007 (11)
O6	0.0372 (10)	0.0439 (11)	0.0458 (11)	−0.0122 (9)	−0.0052 (8)	0.0005 (9)
C6	0.0288 (11)	0.0471 (15)	0.0349 (12)	0.0053 (11)	0.0099 (9)	0.0037 (11)
C7	0.0272 (10)	0.0326 (11)	0.0299 (11)	−0.0003 (10)	0.0100 (9)	−0.0016 (10)
C8	0.0231 (10)	0.0290 (11)	0.0216 (9)	−0.0001 (9)	0.0061 (8)	−0.0008 (8)
C9	0.0265 (10)	0.0242 (11)	0.0227 (9)	0.0003 (9)	0.0080 (8)	0.0003 (8)
C10	0.0266 (10)	0.0284 (11)	0.0216 (10)	0.0015 (9)	0.0079 (8)	0.0022 (8)
C11	0.0260 (10)	0.0234 (10)	0.0266 (10)	0.0023 (9)	0.0105 (8)	−0.0001 (9)
C12	0.0259 (10)	0.0339 (12)	0.0334 (11)	−0.0009 (10)	0.0093 (9)	−0.0004 (10)
C13	0.0380 (13)	0.0425 (15)	0.0485 (15)	−0.0108 (12)	0.0167 (11)	−0.0012 (12)
C14	0.0415 (13)	0.0335 (13)	0.0596 (16)	0.0003 (11)	0.0243 (12)	0.0091 (12)
C15	0.0302 (11)	0.0348 (13)	0.0382 (12)	0.0086 (10)	0.0153 (9)	0.0123 (10)
C16	0.0349 (11)	0.0326 (12)	0.0252 (10)	0.0054 (10)	0.0129 (9)	−0.0005 (9)
C18	0.0293 (11)	0.0408 (13)	0.0248 (11)	0.0008 (10)	0.0024 (9)	−0.0033 (10)
C19	0.0465 (16)	0.101 (3)	0.0454 (15)	0.035 (2)	0.0160 (13)	0.0097 (17)
C20	0.0308 (11)	0.0580 (17)	0.0367 (12)	−0.0110 (13)	0.0043 (10)	0.0017 (13)
C21	0.0295 (12)	0.0495 (17)	0.0575 (17)	0.0076 (12)	0.0112 (11)	−0.0040 (13)

Geometric parameters (Å, º)

O1—C15	1.217 (3)	C7—C8	1.527 (3)
C1—C15	1.528 (3)	C8—C9	1.542 (3)
C1—C16	1.531 (3)	C8—C18	1.556 (3)
C1—C11	1.548 (3)	C9—C10	1.536 (3)
C1—C2	1.558 (3)	C10—C11	1.539 (3)
O2—C7	1.212 (2)	C10—H10	0.9800
C2—C3	1.533 (3)	C11—C12	1.553 (3)
C2—C8	1.588 (3)	C11—H11	0.9800
C2—H2	0.9800	C12—C20	1.517 (3)
O3—C9	1.385 (3)	C12—C21	1.526 (4)
O3—H3	0.88 (3)	C12—C13	1.537 (4)
C3—C4	1.529 (3)	C13—C14	1.536 (4)
C3—H3A	0.9700	C13—H13A	0.9700
C3—H3B	0.9700	C13—H13B	0.9700
O4—C10	1.434 (2)	C14—C15	1.495 (4)
O4—H4	0.89 (3)	C14—H14A	0.9700
C4—C5	1.536 (4)	C14—H14B	0.9700
C4—H4A	0.9700	C16—H16A	0.9700
C4—H4B	0.9700	C16—H16B	0.9700
O5—C16	1.427 (3)	C18—H18	0.9800
O5—C9	1.434 (2)	C19—H19A	0.9300
C5—C6	1.503 (3)	C19—H19B	0.9300
C5—C18	1.528 (4)	C20—H20A	0.9600
C5—H5	0.9800	C20—H20B	0.9600
O6—C18	1.410 (3)	C20—H20C	0.9600
O6—H6	0.822 (19)	C21—H21A	0.9600
C6—C19	1.313 (4)	C21—H21B	0.9600
C6—C7	1.484 (3)	C21—H21C	0.9600
C15—C1—C16	108.32 (17)	C9—C10—H10	107.5
C15—C1—C11	110.18 (18)	C11—C10—H10	107.5
C16—C1—C11	112.86 (18)	C10—C11—C1	108.36 (17)
C15—C1—C2	112.17 (18)	C10—C11—C12	117.13 (18)
C16—C1—C2	106.96 (19)	C1—C11—C12	114.38 (16)
C11—C1—C2	106.35 (15)	C10—C11—H11	105.3
C3—C2—C1	114.35 (17)	C1—C11—H11	105.3
C3—C2—C8	113.51 (18)	C12—C11—H11	105.3
C1—C2—C8	105.90 (17)	C20—C12—C21	109.2 (2)
C3—C2—H2	107.6	C20—C12—C13	107.7 (2)
C1—C2—H2	107.6	C21—C12—C13	109.25 (19)
C8—C2—H2	107.6	C20—C12—C11	110.58 (17)
C9—O3—H3	113 (2)	C21—C12—C11	113.7 (2)
C4—C3—C2	113.05 (19)	C13—C12—C11	106.2 (2)
C4—C3—H3A	109.0	C14—C13—C12	115.4 (2)
C2—C3—H3A	109.0	C14—C13—H13A	108.4
C4—C3—H3B	109.0	C12—C13—H13A	108.4
C2—C3—H3B	109.0	C14—C13—H13B	108.4
H3A—C3—H3B	107.8	C12—C13—H13B	108.4
C10—O4—H4	105.0 (15)	H13A—C13—H13B	107.5
C3—C4—C5	112.4 (2)	C15—C14—C13	114.3 (2)
C3—C4—H4A	109.1	C15—C14—H14A	108.7
C5—C4—H4A	109.1	C13—C14—H14A	108.7
C3—C4—H4B	109.1	C15—C14—H14B	108.7
C5—C4—H4B	109.1	C13—C14—H14B	108.7
H4A—C4—H4B	107.9	H14A—C14—H14B	107.6
C16—O5—C9	112.90 (16)	O1—C15—C14	123.0 (2)
C6—C5—C18	101.69 (19)	O1—C15—C1	121.1 (2)
C6—C5—C4	112.0 (2)	C14—C15—C1	115.90 (19)
C18—C5—C4	110.83 (19)	O5—C16—C1	110.96 (16)
C6—C5—H5	110.7	O5—C16—H16A	109.4
C18—C5—H5	110.7	C1—C16—H16A	109.4
C4—C5—H5	110.7	O5—C16—H16B	109.4
C18—O6—H6	106 (3)	C1—C16—H16B	109.4
C19—C6—C7	122.6 (2)	H16A—C16—H16B	108.0
C19—C6—C5	129.8 (2)	O6—C18—C5	107.37 (19)
C7—C6—C5	107.5 (2)	O6—C18—C8	112.43 (18)
O2—C7—C6	126.0 (2)	C5—C18—C8	100.86 (19)
O2—C7—C8	127.25 (19)	O6—C18—H18	111.9
C6—C7—C8	106.75 (17)	C5—C18—H18	111.9
C7—C8—C9	117.06 (16)	C8—C18—H18	111.9
C7—C8—C18	99.78 (16)	C6—C19—H19A	120.0
C9—C8—C18	114.26 (18)	C6—C19—H19B	120.0
C7—C8—C2	106.27 (18)	H19A—C19—H19B	120.0
C9—C8—C2	109.67 (16)	C12—C20—H20A	109.5
C18—C8—C2	109.09 (16)	C12—C20—H20B	109.5
O3—C9—O5	105.97 (17)	H20A—C20—H20B	109.5
O3—C9—C10	113.14 (16)	C12—C20—H20C	109.5
O5—C9—C10	104.88 (16)	H20A—C20—H20C	109.5
O3—C9—C8	109.10 (16)	H20B—C20—H20C	109.5
O5—C9—C8	107.27 (15)	C12—C21—H21A	109.5
C10—C9—C8	115.77 (18)	C12—C21—H21B	109.5
O4—C10—C9	112.15 (17)	H21A—C21—H21B	109.5
O4—C10—C11	113.00 (18)	C12—C21—H21C	109.5
C9—C10—C11	108.97 (16)	H21A—C21—H21C	109.5
O4—C10—H10	107.5	H21B—C21—H21C	109.5
C15—C1—C2—C3	−45.5 (3)	O3—C9—C10—C11	176.56 (16)
C16—C1—C2—C3	73.1 (2)	O5—C9—C10—C11	−68.4 (2)
C11—C1—C2—C3	−166.0 (2)	C8—C9—C10—C11	49.6 (2)
C15—C1—C2—C8	−171.26 (17)	O4—C10—C11—C1	137.07 (18)
C16—C1—C2—C8	−52.64 (19)	C9—C10—C11—C1	11.7 (2)
C11—C1—C2—C8	68.2 (2)	O4—C10—C11—C12	−91.7 (2)
C1—C2—C3—C4	−165.8 (2)	C9—C10—C11—C12	142.89 (19)
C8—C2—C3—C4	−44.1 (3)	C15—C1—C11—C10	166.60 (18)
C2—C3—C4—C5	37.4 (3)	C16—C1—C11—C10	45.4 (2)
C3—C4—C5—C6	−90.4 (3)	C2—C1—C11—C10	−71.6 (2)
C3—C4—C5—C18	22.4 (3)	C15—C1—C11—C12	33.9 (3)
C18—C5—C6—C19	151.7 (3)	C16—C1—C11—C12	−87.3 (2)
C4—C5—C6—C19	−90.0 (4)	C2—C1—C11—C12	155.72 (19)
C18—C5—C6—C7	−26.6 (3)	C10—C11—C12—C20	49.8 (3)
C4—C5—C6—C7	91.8 (2)	C1—C11—C12—C20	178.2 (2)
C19—C6—C7—O2	−0.1 (5)	C10—C11—C12—C21	−73.5 (2)
C5—C6—C7—O2	178.3 (2)	C1—C11—C12—C21	54.9 (3)
C19—C6—C7—C8	178.9 (3)	C10—C11—C12—C13	166.37 (18)
C5—C6—C7—C8	−2.8 (3)	C1—C11—C12—C13	−65.3 (2)
O2—C7—C8—C9	−27.1 (4)	C20—C12—C13—C14	155.3 (2)
C6—C7—C8—C9	154.0 (2)	C21—C12—C13—C14	−86.2 (3)
O2—C7—C8—C18	−150.9 (3)	C11—C12—C13—C14	36.8 (3)
C6—C7—C8—C18	30.2 (2)	C12—C13—C14—C15	17.6 (3)
O2—C7—C8—C2	95.8 (3)	C13—C14—C15—O1	127.7 (3)
C6—C7—C8—C2	−83.2 (2)	C13—C14—C15—C1	−52.2 (3)
C3—C2—C8—C7	97.9 (2)	C16—C1—C15—O1	−31.1 (3)
C1—C2—C8—C7	−135.89 (17)	C11—C1—C15—O1	−155.0 (2)
C3—C2—C8—C9	−134.73 (19)	C2—C1—C15—O1	86.8 (3)
C1—C2—C8—C9	−8.5 (2)	C16—C1—C15—C14	148.9 (2)
C3—C2—C8—C18	−8.9 (2)	C11—C1—C15—C14	25.0 (3)
C1—C2—C8—C18	117.36 (18)	C2—C1—C15—C14	−93.3 (2)
C16—O5—C9—O3	−172.32 (16)	C9—O5—C16—C1	−9.0 (2)
C16—O5—C9—C10	67.8 (2)	C15—C1—C16—O5	−171.99 (16)
C16—O5—C9—C8	−55.9 (2)	C11—C1—C16—O5	−49.7 (2)
C7—C8—C9—O3	−59.2 (2)	C2—C1—C16—O5	66.9 (2)
C18—C8—C9—O3	56.9 (2)	C6—C5—C18—O6	−72.9 (2)
C2—C8—C9—O3	179.69 (15)	C4—C5—C18—O6	167.96 (18)
C7—C8—C9—O5	−173.55 (18)	C6—C5—C18—C8	45.0 (2)
C18—C8—C9—O5	−57.5 (2)	C4—C5—C18—C8	−74.2 (2)
C2—C8—C9—O5	65.33 (19)	C7—C8—C18—O6	68.1 (2)
C7—C8—C9—C10	69.8 (2)	C9—C8—C18—O6	−57.7 (2)
C18—C8—C9—C10	−174.16 (17)	C2—C8—C18—O6	179.20 (18)
C2—C8—C9—C10	−51.3 (2)	C7—C8—C18—C5	−46.0 (2)
O3—C9—C10—O4	50.7 (2)	C9—C8—C18—C5	−171.76 (17)
O5—C9—C10—O4	165.71 (17)	C2—C8—C18—C5	65.1 (2)
C8—C9—C10—O4	−76.3 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O2	0.89 (3)	1.79 (3)	2.669 (2)	172 (2)
O6—H6···O3	0.82 (2)	1.91 (2)	2.669 (2)	153 (4)
O3—H3···O4^i	0.88 (3)	1.92 (3)	2.780 (2)	164 (4)

Symmetry code: (i) −x+1, y+1/2, −z+1.