4,6-O-Benzyl­idene-1-O-methyl-2,3-deoxy-α-D-glucopyranose-2,3-diyl 1,2-phenyl­ene orthocarbonate

The title compound, C₂₁H₂₀O₈, is the mixed orthocarbonic acid ester of the alcohol components benzene-1,2-diol and 4,6-O-benzyl­idene-1-O-methyl-α-D-glucopyran­oside. The compound represents the first example of a structurally characterized carbohydrate ester of orthocarbonic acid. Both oxacyclic six-membered rings in the structure adopt a chair conformation. The puckered five-membered ring at the spiro centre is present in a twist conformation. No special inter­actions are observed in the mol­ecular packing.

Key indicators

• Single-crystal X-ray study
• T = 200 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.101
• Data-to-parameter ratio = 8.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT180_ALERT_3_C Check Cell Rounding: # of Values Ending with 0 =          3

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           27.59
           From the CIF: _reflns_number_total               2340
           Count of symmetry unique reflns         2364
           Completeness (_total/calc)             98.98%
           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
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C12    = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C13    = .          S
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C14    = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C15    = .          R
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C31    = .          R
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

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

   6 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The spirocyclic orthocarbonate derived from benzene-1,2-diol and 4,6-O-benzylidene-1-O-methyl α-D-glucopyranoside has been prepared to obtain NMR data and structural details for comparison with analogous silicon compounds. In the centre of the molecular structure of (I) a carbon atom is bonded to a benzene-1,2-dioxy group and to the vicinal, trans-configured, 2,3-dioxy function derived from 4,6-O-benzylated methyl α-D-glucopyranoside. Both oxacyclic six-membered rings in the structure adopt a chair conformation. The puckered five-membered ring at the spiro centre is present in a twist conformation.

The molecular packing shows clustering of the aromatic groups about the twofold axes parallel to b. While two of these rings stem from the carbohydrate's protecting group, the other two are provided by phenylene residues.

Related literature

The compound was prepared according to the procedure described by Mues & Buysch (1990). A comparable spirocyclic orthocarbonate has been described recently (Betz & Klüfers, 2007).

S2. Experimental

The compound was obtained upon reaction of equimolar amounts of 2,2-dichlorobenzo[1.3]dioxole and 4,6-O-benzylidene-methyl-α-D-glucopyranoside in the presence of pyridine in dry dichloromethane. Crystals suitable for X-ray analysis were obtained after aqueous workup and subsequent recrystallization of the crude reaction product from hot ethyl acetate.

S3. Refinement

All H atoms were located in a difference map and refined as riding on their parent atoms with C—H = 0.95–1.00 Å. One common isotropic displacement parameter for all H atoms was refined to U_iso(H) = 0.046 (2).

Due to the absence of significant anomalous scattering, Friedel opposites (1736 pairs) have been merged. The absolute configuration is assigned from the carbohydrate starting material.

Computing details

Data collection: COLLECT (Nonius, 2004); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

	Fig. 1. The molecular structure of (I), with atom labels and anisotropic displacement ellipsoids (drawn at the 50% probability level) for non-H atoms.
	Fig. 2. The packing of (I), viewed along [010].

4,6-O-Benzylidene-1-O-methyl-2,3-deoxy-α-D-glucopyranos-2,3-diyl- 1',2'-phenylene orthocarbonate

Crystal data

C21H20O8	F(000) = 840
Mr = 400.37	Dx = 1.455 Mg m^−3
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2y	Cell parameters from 11294 reflections
a = 27.8221 (12) Å	θ = 3.1–27.5°
b = 5.1082 (1) Å	µ = 0.11 mm^−1
c = 13.0090 (5) Å	T = 200 K
β = 98.710 (2)°	Block, colourless
V = 1827.53 (11) Å^3	0.13 × 0.07 × 0.04 mm
Z = 4

Data collection

Nonius Kappa CCD diffractometer	2340 independent reflections
Radiation source: fine-focus sealed tube	1770 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.056
φ and ω scans	θmax = 27.6°, θmin = 3.1°
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997)	h = −36→36
Tmin = 0.985, Tmax = 0.996	k = −6→6
17337 measured reflections	l = −16→16

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: difference Fourier map
wR(F^2) = 0.101	Only H-atom displacement parameters refined
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0524P)^2 + 0.4733P] where P = (Fo^2 + 2Fc^2)/3
2340 reflections	(Δ/σ)max < 0.001
264 parameters	Δρmax = 0.17 e Å^−3
1 restraint	Δρmin = −0.25 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
O11	0.64380 (6)	0.9042 (4)	0.57076 (14)	0.0319 (4)
O12	0.74938 (6)	0.6047 (4)	0.73260 (13)	0.0329 (5)
O13	0.69284 (6)	0.4286 (4)	0.82183 (13)	0.0346 (5)
O14	0.58259 (6)	0.4525 (4)	0.73050 (13)	0.0291 (4)
O16	0.52502 (6)	0.6614 (4)	0.60767 (14)	0.0339 (5)
O17	0.69720 (7)	0.5838 (4)	0.52112 (14)	0.0377 (5)
O21	0.76376 (7)	0.2029 (4)	0.80564 (14)	0.0340 (5)
O22	0.76541 (7)	0.5557 (4)	0.91262 (14)	0.0333 (5)
C10	0.74231 (10)	0.4493 (6)	0.8183 (2)	0.0321 (6)
C11	0.69259 (10)	0.8021 (6)	0.5832 (2)	0.0328 (6)
H11	0.7158	0.9421	0.5686	0.046 (2)*
C12	0.70311 (9)	0.7217 (6)	0.6967 (2)	0.0284 (6)
H12	0.6990	0.8779	0.7409	0.046 (2)*
C13	0.66896 (9)	0.5106 (6)	0.72079 (19)	0.0288 (6)
H13	0.6686	0.3638	0.6698	0.046 (2)*
C14	0.61956 (9)	0.6315 (5)	0.71191 (18)	0.0260 (6)
H14	0.6202	0.7856	0.7595	0.046 (2)*
C15	0.60867 (9)	0.7212 (6)	0.5974 (2)	0.0276 (6)
H15	0.6081	0.5646	0.5511	0.046 (2)*
C16	0.55935 (9)	0.8494 (6)	0.5802 (2)	0.0342 (7)
H161	0.5595	1.0076	0.6242	0.046 (2)*
H162	0.5506	0.9018	0.5065	0.046 (2)*
C17	0.68845 (12)	0.6421 (9)	0.4118 (2)	0.0523 (10)
H171	0.7102	0.7832	0.3967	0.046 (2)*
H172	0.6546	0.6973	0.3919	0.046 (2)*
H173	0.6946	0.4854	0.3723	0.046 (2)*
C21	0.80707 (10)	0.2023 (6)	0.8741 (2)	0.0291 (6)
C22	0.80802 (9)	0.4151 (6)	0.9392 (2)	0.0290 (6)
C23	0.84633 (10)	0.4667 (6)	1.0154 (2)	0.0345 (7)
H23	0.8465	0.6115	1.0613	0.046 (2)*
C24	0.88525 (11)	0.2911 (7)	1.0211 (2)	0.0398 (7)
H24	0.9131	0.3189	1.0720	0.046 (2)*
C25	0.88453 (10)	0.0791 (7)	0.9552 (2)	0.0390 (7)
H25	0.9117	−0.0353	0.9621	0.046 (2)*
C26	0.84470 (10)	0.0285 (6)	0.8783 (2)	0.0355 (7)
H26	0.8439	−0.1164	0.8323	0.046 (2)*
C31	0.53608 (9)	0.5784 (6)	0.71128 (19)	0.0291 (6)
H31	0.5360	0.7326	0.7586	0.046 (2)*
C32	0.49829 (9)	0.3857 (6)	0.7332 (2)	0.0293 (6)
C33	0.50281 (11)	0.2628 (7)	0.8290 (2)	0.0398 (7)
H33	0.5299	0.3006	0.8806	0.046 (2)*
C34	0.46786 (11)	0.0846 (7)	0.8501 (2)	0.0455 (8)
H34	0.4714	−0.0005	0.9158	0.046 (2)*
C35	0.42799 (11)	0.0302 (7)	0.7761 (2)	0.0422 (8)
H35	0.4039	−0.0902	0.7909	0.046 (2)*
C36	0.42350 (11)	0.1516 (7)	0.6813 (2)	0.0471 (8)
H36	0.3962	0.1144	0.6301	0.046 (2)*
C37	0.45846 (11)	0.3288 (7)	0.6594 (2)	0.0405 (7)
H37	0.4550	0.4114	0.5933	0.046 (2)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O11	0.0248 (10)	0.0316 (10)	0.0392 (10)	−0.0017 (8)	0.0047 (8)	0.0066 (9)
O12	0.0215 (9)	0.0391 (11)	0.0371 (10)	−0.0003 (9)	0.0013 (7)	0.0075 (10)
O13	0.0222 (10)	0.0473 (12)	0.0329 (10)	0.0002 (9)	−0.0002 (7)	0.0123 (9)
O14	0.0204 (9)	0.0324 (10)	0.0342 (9)	−0.0039 (8)	0.0033 (7)	0.0014 (9)
O16	0.0233 (10)	0.0419 (11)	0.0354 (10)	−0.0035 (9)	0.0006 (8)	0.0060 (9)
O17	0.0357 (11)	0.0485 (13)	0.0297 (9)	0.0033 (10)	0.0076 (8)	−0.0004 (10)
O21	0.0278 (10)	0.0324 (10)	0.0394 (11)	−0.0006 (9)	−0.0028 (8)	−0.0020 (9)
O22	0.0273 (10)	0.0360 (11)	0.0349 (10)	0.0041 (9)	−0.0010 (8)	−0.0030 (9)
C10	0.0255 (15)	0.0357 (16)	0.0339 (14)	0.0003 (12)	0.0001 (11)	0.0034 (13)
C11	0.0225 (14)	0.0365 (15)	0.0390 (15)	−0.0012 (12)	0.0028 (12)	0.0055 (13)
C12	0.0202 (13)	0.0315 (14)	0.0326 (14)	0.0009 (11)	0.0012 (11)	−0.0005 (12)
C13	0.0232 (13)	0.0352 (15)	0.0275 (13)	−0.0013 (12)	0.0018 (10)	0.0017 (12)
C14	0.0217 (13)	0.0284 (14)	0.0277 (13)	−0.0020 (11)	0.0030 (10)	0.0001 (12)
C15	0.0245 (13)	0.0293 (14)	0.0285 (13)	−0.0035 (12)	0.0023 (10)	−0.0005 (11)
C16	0.0239 (14)	0.0399 (16)	0.0377 (15)	0.0004 (13)	0.0015 (12)	0.0081 (13)
C17	0.0449 (19)	0.082 (3)	0.0305 (15)	0.011 (2)	0.0081 (13)	0.0072 (18)
C21	0.0252 (14)	0.0315 (14)	0.0300 (13)	−0.0008 (12)	0.0019 (11)	0.0044 (12)
C22	0.0231 (14)	0.0337 (15)	0.0304 (13)	0.0014 (12)	0.0045 (10)	0.0057 (12)
C23	0.0346 (16)	0.0424 (16)	0.0254 (13)	−0.0034 (13)	0.0009 (11)	0.0017 (13)
C24	0.0309 (15)	0.054 (2)	0.0325 (15)	−0.0007 (15)	−0.0015 (12)	0.0132 (14)
C25	0.0270 (15)	0.0445 (18)	0.0447 (16)	0.0086 (14)	0.0027 (12)	0.0160 (15)
C26	0.0353 (16)	0.0321 (15)	0.0393 (15)	0.0017 (13)	0.0063 (12)	0.0073 (13)
C31	0.0217 (13)	0.0352 (14)	0.0298 (13)	0.0016 (12)	0.0016 (10)	−0.0019 (12)
C32	0.0227 (13)	0.0343 (15)	0.0316 (14)	−0.0002 (12)	0.0062 (11)	−0.0047 (12)
C33	0.0323 (16)	0.052 (2)	0.0356 (15)	−0.0069 (14)	0.0048 (12)	0.0023 (15)
C34	0.0438 (18)	0.054 (2)	0.0397 (16)	−0.0089 (17)	0.0107 (14)	0.0083 (16)
C35	0.0325 (16)	0.0449 (18)	0.0519 (18)	−0.0090 (15)	0.0149 (14)	0.0001 (15)
C36	0.0346 (17)	0.056 (2)	0.0487 (18)	−0.0153 (16)	−0.0012 (14)	−0.0020 (17)
C37	0.0329 (16)	0.0477 (18)	0.0393 (16)	−0.0100 (14)	0.0011 (13)	0.0036 (15)

Geometric parameters (Å, º)

O11—C15	1.432 (3)	C16—H162	0.990
O11—C11	1.440 (3)	C17—H171	0.980
O12—C10	1.407 (3)	C17—H172	0.980
O12—C12	1.432 (3)	C17—H173	0.980
O13—C10	1.388 (3)	C21—C26	1.367 (4)
O13—C13	1.442 (3)	C21—C22	1.376 (4)
O14—C14	1.424 (3)	C22—C23	1.367 (4)
O14—C31	1.433 (3)	C23—C24	1.399 (4)
O16—C31	1.402 (3)	C23—H23	0.950
O16—C16	1.437 (3)	C24—C25	1.380 (5)
O17—C11	1.394 (4)	C24—H24	0.950
O17—C17	1.437 (3)	C25—C26	1.400 (4)
O21—C21	1.386 (3)	C25—H25	0.950
O21—C10	1.413 (4)	C26—H26	0.950
O22—C22	1.385 (3)	C31—C32	1.499 (4)
O22—C10	1.405 (3)	C31—H31	1.000
C11—C12	1.518 (4)	C32—C37	1.382 (4)
C11—H11	1.000	C32—C33	1.384 (4)
C12—C13	1.501 (4)	C33—C34	1.390 (4)
C12—H12	1.000	C33—H33	0.950
C13—C14	1.495 (4)	C34—C35	1.382 (4)
C13—H13	1.000	C34—H34	0.950
C14—C15	1.545 (3)	C35—C36	1.369 (4)
C14—H14	1.000	C35—H35	0.950
C15—C16	1.506 (4)	C36—C37	1.389 (4)
C15—H15	1.000	C36—H36	0.950
C16—H161	0.990	C37—H37	0.950
C15—O11—C11	113.7 (2)	H161—C16—H162	108.5
C10—O12—C12	105.5 (2)	O17—C17—H171	109.5
C10—O13—C13	105.67 (19)	O17—C17—H172	109.5
C14—O14—C31	109.77 (19)	H171—C17—H172	109.5
C31—O16—C16	112.5 (2)	O17—C17—H173	109.5
C11—O17—C17	113.0 (3)	H171—C17—H173	109.5
C21—O21—C10	105.6 (2)	H172—C17—H173	109.5
C22—O22—C10	106.2 (2)	C26—C21—C22	123.0 (2)
O13—C10—O22	109.0 (2)	C26—C21—O21	127.8 (3)
O13—C10—O12	109.1 (2)	C22—C21—O21	109.1 (2)
O22—C10—O12	111.9 (2)	C23—C22—C21	122.6 (3)
O13—C10—O21	112.0 (2)	C23—C22—O22	128.7 (3)
O22—C10—O21	107.5 (2)	C21—C22—O22	108.7 (2)
O12—C10—O21	107.3 (2)	C22—C23—C24	115.3 (3)
O17—C11—O11	113.1 (2)	C22—C23—H23	122.4
O17—C11—C12	109.0 (2)	C24—C23—H23	122.4
O11—C11—C12	104.3 (2)	C25—C24—C23	122.1 (3)
O17—C11—H11	110.1	C25—C24—H24	118.9
O11—C11—H11	110.1	C23—C24—H24	118.9
C12—C11—H11	110.1	C24—C25—C26	121.6 (3)
O12—C12—C13	101.4 (2)	C24—C25—H25	119.2
O12—C12—C11	117.5 (2)	C26—C25—H25	119.2
C13—C12—C11	111.2 (2)	C21—C26—C25	115.3 (3)
O12—C12—H12	108.8	C21—C26—H26	122.4
C13—C12—H12	108.8	C25—C26—H26	122.4
C11—C12—H12	108.8	O16—C31—O14	111.4 (2)
O13—C13—C14	118.8 (2)	O16—C31—C32	108.9 (2)
O13—C13—C12	100.36 (19)	O14—C31—C32	108.2 (2)
C14—C13—C12	106.9 (2)	O16—C31—H31	109.4
O13—C13—H13	110.1	O14—C31—H31	109.4
C14—C13—H13	110.1	C32—C31—H31	109.4
C12—C13—H13	110.1	C37—C32—C33	118.9 (3)
O14—C14—C13	113.6 (2)	C37—C32—C31	121.2 (2)
O14—C14—C15	108.25 (19)	C33—C32—C31	119.9 (2)
C13—C14—C15	103.9 (2)	C32—C33—C34	120.3 (3)
O14—C14—H14	110.3	C32—C33—H33	119.9
C13—C14—H14	110.3	C34—C33—H33	119.9
C15—C14—H14	110.3	C35—C34—C33	120.4 (3)
O11—C15—C16	108.7 (2)	C35—C34—H34	119.8
O11—C15—C14	112.67 (19)	C33—C34—H34	119.8
C16—C15—C14	108.2 (2)	C36—C35—C34	119.4 (3)
O11—C15—H15	109.1	C36—C35—H35	120.3
C16—C15—H15	109.1	C34—C35—H35	120.3
C14—C15—H15	109.1	C35—C36—C37	120.6 (3)
O16—C16—C15	107.3 (2)	C35—C36—H36	119.7
O16—C16—H161	110.2	C37—C36—H36	119.7
C15—C16—H161	110.2	C32—C37—C36	120.5 (3)
O16—C16—H162	110.2	C32—C37—H37	119.8
C15—C16—H162	110.2	C36—C37—H37	119.8
C13—O13—C10—O22	138.5 (2)	C13—C14—C15—O11	−59.3 (3)
C13—O13—C10—O12	16.0 (3)	O14—C14—C15—C16	59.4 (3)
C13—O13—C10—O21	−102.6 (2)	C13—C14—C15—C16	−179.5 (2)
C22—O22—C10—O13	138.2 (2)	C31—O16—C16—C15	59.3 (3)
C22—O22—C10—O12	−101.0 (3)	O11—C15—C16—O16	−179.92 (19)
C22—O22—C10—O21	16.6 (3)	C14—C15—C16—O16	−57.3 (3)
C12—O12—C10—O13	11.6 (3)	C10—O21—C21—C26	−167.6 (3)
C12—O12—C10—O22	−109.1 (2)	C10—O21—C21—C22	10.7 (3)
C12—O12—C10—O21	133.1 (2)	C26—C21—C22—C23	−1.6 (4)
C21—O21—C10—O13	−136.5 (2)	O21—C21—C22—C23	180.0 (2)
C21—O21—C10—O22	−16.8 (3)	C26—C21—C22—O22	177.9 (2)
C21—O21—C10—O12	103.8 (2)	O21—C21—C22—O22	−0.5 (3)
C17—O17—C11—O11	65.2 (3)	C10—O22—C22—C23	169.5 (3)
C17—O17—C11—C12	−179.3 (2)	C10—O22—C22—C21	−10.1 (3)
C15—O11—C11—O17	60.5 (3)	C21—C22—C23—C24	1.5 (4)
C15—O11—C11—C12	−57.8 (3)	O22—C22—C23—C24	−177.9 (3)
C10—O12—C12—C13	−33.0 (2)	C22—C23—C24—C25	−0.9 (4)
C10—O12—C12—C11	−154.4 (2)	C23—C24—C25—C26	0.3 (4)
O17—C11—C12—O12	57.3 (3)	C22—C21—C26—C25	0.9 (4)
O11—C11—C12—O12	178.4 (2)	O21—C21—C26—C25	179.0 (3)
O17—C11—C12—C13	−58.9 (3)	C24—C25—C26—C21	−0.3 (4)
O11—C11—C12—C13	62.2 (3)	C16—O16—C31—O14	−61.3 (3)
C10—O13—C13—C14	−151.3 (2)	C16—O16—C31—C32	179.4 (2)
C10—O13—C13—C12	−35.4 (3)	C14—O14—C31—O16	61.2 (3)
O12—C12—C13—O13	41.6 (2)	C14—O14—C31—C32	−179.14 (18)
C11—C12—C13—O13	167.3 (2)	O16—C31—C32—C37	−4.4 (4)
O12—C12—C13—C14	166.13 (19)	O14—C31—C32—C37	−125.6 (3)
C11—C12—C13—C14	−68.2 (3)	O16—C31—C32—C33	176.1 (3)
C31—O14—C14—C13	−174.84 (19)	O14—C31—C32—C33	54.9 (3)
C31—O14—C14—C15	−60.0 (2)	C37—C32—C33—C34	0.3 (4)
O13—C13—C14—O14	−68.9 (3)	C31—C32—C33—C34	179.8 (3)
C12—C13—C14—O14	178.70 (19)	C32—C33—C34—C35	−0.7 (5)
O13—C13—C14—C15	173.7 (2)	C33—C34—C35—C36	0.7 (5)
C12—C13—C14—C15	61.3 (3)	C34—C35—C36—C37	−0.3 (5)
C11—O11—C15—C16	−179.5 (2)	C33—C32—C37—C36	0.2 (5)
C11—O11—C15—C14	60.6 (3)	C31—C32—C37—C36	−179.4 (3)
O14—C14—C15—O11	179.6 (2)	C35—C36—C37—C32	−0.2 (5)