Potassium (1R,4R,5S,8S)-4,5,8-trihy­droxy-3-oxo-2,6-dioxabicyclo­[3.3.0]octane-4-sulfonate dihydrate

The title salt, K⁺·C₆H₇O₉S^-·2H₂O, formed by reaction of dehydro-L-ascorbic acid with potassium hydrogen sulfite in water, crystallizes as colourless plates. The potassium ion is coordinated by eight O atoms arising from hy­droxy or sulfonate groups. The sulfonate group is bonded to the C atom neighbouring that of the lactone carbonyl group. As is commonly observed in crystalline L-ascorbic acid derivatives, the O atom of the primary hy­droxy group is linked to the second C atom from the lactone C atom, forming a hemi-acetal function, thereby creating a bicyclic system of two fused five-membered rings, both of which have envelope conformations with one of the shared C atoms as the flap. Addition of the sulfur nucleophile occurs from the less hindered face. One of the two independent lattice water mol­ecules has hydrogen bonds to sulfonate O atoms of two different anions and is the acceptor of bonds from hy­droxy groups of two further anions; the second lattice water mol­ecule donates to the carbonyl and a hy­droxy O atom in different anions, and accepts from a hy­droxy O atom in a further anion. Thus, through K-O coordination and hydrogen bonds, the potassium cations, sulfonate anions and water mol­ecules are linked in a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 140 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.018
• wR factor = 0.048
• Data-to-parameter ratio = 9.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT354_ALERT_3_C Short   O-H Bond (0.82A)   O5     -   H5O    ...       0.70 Ang.
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          5

Alert level G
PLAT004_ALERT_5_G Info: Polymeric Structure Found with Dimension .          2
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ          ?
PLAT063_ALERT_4_G Crystal Size Likely too Large for Beam Size ....       0.80 mm
PLAT164_ALERT_4_G Nr. of Refined C-H H-Atoms in Heavy-Atom Struct.          4
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          4
PLAT764_ALERT_4_G Overcomplete CIF Bond List Detected (Rep/Expd) .       1.24 Ratio
PLAT791_ALERT_4_G Note: The Model has Chirality at C2     (Verify)          S
PLAT791_ALERT_4_G Note: The Model has Chirality at C3     (Verify)          S
PLAT791_ALERT_4_G Note: The Model has Chirality at C4     (Verify)          R
PLAT791_ALERT_4_G Note: The Model has Chirality at C5     (Verify)          S
PLAT850_ALERT_4_G Check Flack Parameter Exact Value 0.00 and su ..       0.04
PLAT909_ALERT_3_G Percentage of Observed Data at Theta(Max) still          99 Perc.
PLAT961_ALERT_5_G Dataset Contains no Negative Intensities .......          !

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  14 ALERT level G = General information/check it is not something unexpected

   1 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
   3 ALERT type 3 Indicator that the structure quality may be low
   9 ALERT type 4 Improvement, methodology, query or suggestion
   3 ALERT type 5 Informative message, check

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S1. Comment

The addition of hydrogen sulfite (bisulfite) anion to carbonyl compounds to form sulfonic acid salts has found use in the purification of aldehydes and some ketones. Certain carbohydrates, despite existing preponderately in a hemi-acetal form, also give such adducts and the crystalline structures of the potassium sulfonic acid salts of D-glucose and D-mannose (Cole et al., 2001), D-galactose (Haines & Hughes, 2010) and the sodium sulfonic salt of D-glucose (Haines & Hughes, 2012) have been determined by X-ray crystallographic studies and all shown to exist in an acyclic form.

Ingles (1961) reported the preparation of an addition product between potassium hydrogen sulfite and dehydro-L-ascorbic acid. This compound, with carbonyl functionality at C1, C2 and C3, has potentially three sites of attack by the anion, but the carbonyl group at C1 is incorporated in a lactone structure and therefore is the least likely to undergo nucleophilic attack by the sulfur but the question of formation of a C2 or C3 adduct remained open. Our present study was undertaken to determine the structure of this compound.

Preparation of the adduct by reaction of potassium hydrogen sulfite (generated in aqueous solution from potassium metabisulfite) and dehydro-L-ascorbic acid in water by the published procedure gave, as reported, the adduct as a dihydrate with properties (m.p. and [α]_D) in agreement with those described (Ingles, 1961). HRESIMS (negative ion mode, methanol solution) did not show an expected peak at m/e 254.9816 for [C₆H₇O₉S]^- but showed peaks at 173.0089 for the dehydro-L-ascorbic acid anion (calculated for [C₆H₅O₆]^-: m/z 173.0092) and the ion of the methanol adduct at 205.0349 (calcd for [C₇H₉O₇]^-: m/z 205.0354), indicating instability of the adduct in the methanol solution.

The crystal structure indicates attachment of the sulfur at C2 on the opposite side of the fused ring formed by attack of O6 on the C3 carbonyl function (Figure 1). This bicyclic motif for L-ascorbic acid derivatives in which the two rings share the C3—C4 bond is a common feature revealed in many crystal structures determined by X-ray crystallography, for example the dehydro-L-ascorbic acid dimer (Hvoslef, 1972) and the marine natural product delesserine (Yvin et al., 1982). Both rings have envelope conformations and C3 is the flap out-of-plane atom in each. The potassium ions are eight-coordinate (Figures 1 and 2) with a coordination sphere between that of a square antiprism (in which one of the square planes is O22, O23ⁱⁱ, O2ⁱⁱⁱ, and O6ⁱⁱⁱ; for symmetry codes, see: 'Geometric parameters Table') and dodecahedral (in which the pairs of `pseudo-equatorial' B-site atoms are O22, O5ⁱ and O21^iv, O2ⁱⁱⁱ). Each potassium ion is bonded to O atoms of five different anions with K—O bond lengths in the range 2.6757 (13) – 3.0265 (13) Å. Of the two lattice water molecules, that containing O8 has hydrogen bonds to oxygen atoms in different sulfonate groups (Table1, Figure 3) and is the acceptor of two hydrogen bonds, from H2O and H3O in different anions, leading to an approximately tetrahedral arrangement about the O8 atom. The water molecule of O9 accepts a single hydrogen bond from an H5O atom and donates two hydrogen bonds, to O1 and O5, in different anions (Figure 3); the trigonal arrangement at the O9 atom has an umbrella shape. Thus, through K—O coordination and hydrogen bonds, potassium cations, sulfonate anions and water molecules are linked in a three-dimensional network.

Related literature

For the first synthesis of the title compound, see: Ingles (1961). For related studies on crystalline properties of hydrogen sulfite addition products of carbohydrates and their structures, see: Cole et al. (2001); Haines & Hughes (2010, 2012). For examples of related bicyclic structures based on dehydro-L-ascorbic acid, see: Hvoslef (1972); Yvin et al. (1982).

S2. Experimental

The title compound was prepared by a procedure similar to that described (Ingles, 1961). L-Ascorbic acid (1.76 g) was oxidized by shaking with iodine (2.48 g) in MeOH (15 ml) and the solution neutralized with basic lead carbonate (7 g), then filtered through kieselguhr. The syrup obtained on evaporation of the solution was dissolved in water (1.2 ml) and added to a solution of potassium hydrogen sulfite made by dissolving potassium metabisulfite (1.11 g) in water (1.6 ml). The crystals that formed were collected, washed with 95% EtOH and dried under vacuum over P₂O₅, m.p. (with swelling) 401–403 K with gradual decomposition to 473 K [lit. slow decomposition above 423 K (Ingles, 1961)]; [α]_D²⁴ +38.5 (c, 0.74, 9:1 H₂O:HOAc), lit. [α]_D +35 (c 1.5, 9:1 H₂O:HOAc). ¹H NMR (D₂O, 400 MHz, reference Me₃COH at δ_H 1.24): δ 4.95 (br s, H-4), 4.63 (ddd, J_5,6a = 5, J_{5,6 b} = 2.5, J_4,5 = 0.6 Hz, H-5), 4.24 (dd, J_6a,6b = 10.4 Hz, H-6a), 4.18 (dd, H-6 b). ¹³C NMR (D₂O, 100 MHz, referenced to Me₃COH at δ_C 30.29): δ 172.33 (C1), 107.17 (C3), 88.88 (C2), 88.70 (C4), 76.06 (C6), 73.64 (C5).

HRESIMS (negative ion mode, measured in MeOH solution) gave no peak at the expected m/z [C₆H₇O₉S₁]^- but predominant peaks were observed at m/z 173.0089 ([C₆H₅O₆]^-), and 205.0349 ([C₇H₉O₇]^-) which indicated (i) decomposition of the sulfonate in solution to dehydro-L-ascorbic acid, and (ii) addition of methanol to this decomposition product.

S3. Refinement

Hydrogen atoms were located in difference maps and were all refined freely except, in the final cycles, the U_iso parameters of the methine hydrogen atoms were set at 1.2^.U_eq of the parent carbon atoms.

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2010); cell refinement: CrysAlis CCD (Oxford Diffraction, 2010); data reduction: CrysAlis RED (Oxford Diffraction, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Johnson, 1976) and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and WinGX (Farrugia, 2012).

Figures

	Fig. 1. View of the expanded asymmetric unit of K^+.C6H7O9S^-.2H2O, showing the conformation of the anion, the coordination of the potassium cation and the locations of the water molecules; all the potassium ions bonded to the anion are included. In all the figures, thermal ellipsoids are drawn at the 50% probability level, and hydrogen atoms are drawn as spheres of arbitrary size. Superscripts in the atom labels denote symmetry operations as defined in the Tables of molecular dimensions and hydrogen bonds.
	Fig. 2. A section through the unit cell, showing the linking of the different moieties through K—O coordination bonds.
	Fig. 3. A section through the unit cell (as Figure 2), showing the linking of the different moieties through hydrogen bonds (dashed lines).

Potassium (1R,4R,5S,8S)-4,5,8-trihydroxy-3-oxo-2,6-dioxabicyclo[3.3.0]octane-4-sulfonate dihydrate

Crystal data

K^+·C6H7O9S^−·2H2O	F(000) = 680
Mr = 330.31	Dx = 1.903 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 9940 reflections
a = 6.21040 (15) Å	θ = 3.6–32.6°
b = 6.93014 (16) Å	µ = 0.70 mm^−1
c = 26.7851 (7) Å	T = 140 K
V = 1152.80 (5) Å^3	Plate, colourless
Z = 4	0.80 × 0.40 × 0.10 mm

Data collection

Oxford Diffraction Xcalibur 3/Sapphire3 CCD diffractometer	2022 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2012 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.026
Detector resolution: 16.0050 pixels mm^-1	θmax = 25.0°, θmin = 3.6°
Thin slice φ and ω scans	h = −7→7
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2010)	k = −8→8
Tmin = 0.851, Tmax = 1.000	l = −31→31
15452 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.018	All H-atom parameters refined
wR(F^2) = 0.048	w = 1/[σ^2(Fo^2) + (0.0259P)^2 + 0.3818P] where P = (Fo^2 + 2Fc^2)/3
S = 1.13	(Δ/σ)max = 0.002
2022 reflections	Δρmax = 0.22 e Å^−3
214 parameters	Δρmin = −0.24 e Å^−3
0 restraints	Absolute structure: Flack (1983), 806 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.00 (4)

Special details

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 > 2σ(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
K	0.43096 (6)	0.06331 (5)	0.592707 (13)	0.01341 (10)
C1	0.7395 (3)	0.4927 (2)	0.64787 (6)	0.0130 (4)
C2	0.7781 (3)	0.6005 (2)	0.59853 (6)	0.0101 (3)
C3	0.9401 (3)	0.7544 (2)	0.61585 (6)	0.0101 (3)
C4	1.0569 (3)	0.6623 (2)	0.66013 (6)	0.0118 (4)
H4	1.179 (3)	0.591 (3)	0.6515 (7)	0.014*
C5	1.0939 (3)	0.8288 (2)	0.69651 (7)	0.0143 (4)
H5	1.068 (3)	0.790 (3)	0.7284 (8)	0.017*
C6	0.9307 (3)	0.9816 (3)	0.68001 (7)	0.0163 (4)
O1	0.5875 (2)	0.39178 (19)	0.65771 (5)	0.0213 (3)
O2	0.5917 (2)	0.68214 (18)	0.57932 (5)	0.0152 (3)
O3	1.0843 (2)	0.82586 (17)	0.58160 (5)	0.0132 (3)
O4	0.8989 (2)	0.52687 (17)	0.68067 (4)	0.0146 (3)
O5	1.3044 (2)	0.9069 (2)	0.69025 (5)	0.0168 (3)
O6	0.81153 (19)	0.90096 (17)	0.63873 (4)	0.0133 (3)
S2	0.89769 (6)	0.42594 (6)	0.555030 (14)	0.01075 (10)
O21	1.0867 (2)	0.35166 (17)	0.58032 (5)	0.0163 (3)
O22	0.7275 (2)	0.28416 (18)	0.54814 (4)	0.0170 (3)
O23	0.9402 (2)	0.53401 (17)	0.50966 (4)	0.0144 (3)
O8	0.8855 (2)	0.9517 (2)	0.50022 (5)	0.0136 (3)
O9	0.4146 (3)	0.2464 (2)	0.74597 (5)	0.0243 (3)
H6A	1.006 (4)	1.106 (3)	0.6699 (7)	0.018 (5)*
H6B	0.828 (4)	1.008 (3)	0.7059 (8)	0.023 (6)*
H2O	0.548 (4)	0.623 (4)	0.5572 (9)	0.034 (7)*
H3O	1.013 (4)	0.860 (4)	0.5587 (9)	0.036 (7)*
H5O	1.375 (5)	0.847 (4)	0.7033 (10)	0.032 (8)*
H8OA	0.856 (4)	1.063 (5)	0.5060 (10)	0.049 (9)*
H8OB	0.775 (4)	0.904 (4)	0.4948 (9)	0.028 (7)*
H9OA	0.377 (5)	0.146 (5)	0.7374 (11)	0.048 (9)*
H9OB	0.468 (5)	0.296 (4)	0.7205 (11)	0.042 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
K	0.01291 (17)	0.01296 (18)	0.01436 (18)	−0.00271 (16)	0.00075 (14)	−0.00059 (14)
C1	0.0148 (8)	0.0111 (8)	0.0130 (8)	0.0003 (7)	0.0025 (7)	−0.0026 (7)
C2	0.0099 (7)	0.0094 (8)	0.0111 (8)	0.0005 (7)	0.0002 (6)	−0.0016 (7)
C3	0.0109 (8)	0.0088 (8)	0.0107 (7)	−0.0001 (7)	0.0014 (7)	−0.0007 (6)
C4	0.0121 (9)	0.0111 (8)	0.0121 (8)	−0.0016 (8)	−0.0005 (7)	0.0008 (6)
C5	0.0165 (9)	0.0167 (9)	0.0099 (8)	−0.0046 (8)	−0.0013 (8)	−0.0007 (7)
C6	0.0160 (9)	0.0157 (9)	0.0174 (9)	−0.0009 (8)	−0.0012 (8)	−0.0078 (7)
O1	0.0230 (7)	0.0234 (7)	0.0174 (6)	−0.0114 (7)	0.0046 (6)	0.0005 (5)
O2	0.0115 (6)	0.0157 (6)	0.0183 (6)	0.0036 (6)	−0.0058 (5)	−0.0063 (5)
O3	0.0132 (6)	0.0137 (6)	0.0127 (6)	−0.0036 (6)	−0.0014 (5)	0.0029 (5)
O4	0.0188 (6)	0.0121 (6)	0.0129 (6)	−0.0036 (6)	−0.0004 (5)	0.0021 (4)
O5	0.0132 (6)	0.0164 (7)	0.0208 (7)	−0.0017 (6)	−0.0064 (5)	0.0006 (6)
O6	0.0139 (6)	0.0109 (6)	0.0152 (6)	0.0020 (5)	−0.0032 (5)	−0.0045 (5)
S2	0.0124 (2)	0.00826 (19)	0.01156 (19)	−0.00009 (19)	0.00120 (15)	−0.00172 (16)
O21	0.0160 (6)	0.0148 (6)	0.0183 (6)	0.0044 (6)	−0.0009 (6)	−0.0006 (5)
O22	0.0191 (7)	0.0127 (6)	0.0192 (7)	−0.0032 (6)	0.0028 (5)	−0.0036 (5)
O23	0.0178 (6)	0.0140 (6)	0.0115 (6)	−0.0013 (5)	0.0032 (5)	−0.0011 (5)
O8	0.0131 (7)	0.0118 (7)	0.0158 (6)	−0.0009 (6)	−0.0007 (5)	−0.0020 (5)
O9	0.0335 (8)	0.0240 (8)	0.0154 (7)	−0.0131 (7)	0.0015 (7)	−0.0031 (6)

Geometric parameters (Å, º)

K—O22	2.6757 (13)	C5—C6	1.531 (3)
K—O3^i	2.7259 (13)	C5—H5	0.91 (2)
K—O23^ii	2.8243 (12)	C6—O6	1.443 (2)
K—O2^iii	2.8466 (13)	C6—H6A	1.02 (2)
K—O6^iii	2.8934 (12)	C6—H6B	0.96 (2)
K—O5^i	2.9356 (14)	O2—K^v	2.8466 (13)
K—O21^iv	2.9455 (13)	O2—H2O	0.77 (3)
K—O1	3.0265 (13)	O3—K^vi	2.7259 (13)
C1—O1	1.204 (2)	O3—H3O	0.79 (3)
C1—O4	1.344 (2)	O5—K^vi	2.9356 (14)
C1—C2	1.537 (2)	O5—H5O	0.70 (3)
C2—O2	1.387 (2)	O6—K^v	2.8934 (12)
C2—C3	1.538 (2)	S2—O21	1.4495 (13)
C2—S2	1.8364 (17)	S2—O23	1.4517 (12)
C3—O3	1.374 (2)	S2—O22	1.4547 (13)
C3—O6	1.430 (2)	O21—K^vii	2.9455 (13)
C3—C4	1.529 (2)	O23—K^viii	2.8243 (12)
C4—O4	1.465 (2)	O8—H8OA	0.81 (3)
C4—C5	1.528 (2)	O8—H8OB	0.78 (3)
C4—H4	0.94 (2)	O9—H9OA	0.77 (3)
C5—O5	1.425 (2)	O9—H9OB	0.83 (3)
O22—K—O3^i	147.16 (4)	O4—C4—C5	110.19 (13)
O22—K—O23^ii	71.91 (4)	O4—C4—C3	103.95 (13)
O3^i—K—O23^ii	76.47 (4)	C5—C4—C3	104.51 (14)
O22—K—O2^iii	103.48 (4)	O4—C4—H4	107.4 (12)
O3^i—K—O2^iii	72.73 (4)	C5—C4—H4	115.7 (12)
O23^ii—K—O2^iii	69.45 (4)	C3—C4—H4	114.5 (12)
O22—K—O6^iii	81.39 (4)	O5—C5—C4	110.47 (15)
O3^i—K—O6^iii	117.19 (4)	O5—C5—C6	108.10 (14)
O23^ii—K—O6^iii	107.71 (4)	C4—C5—C6	103.82 (14)
O2^iii—K—O6^iii	53.58 (4)	O5—C5—H5	112.8 (13)
O22—K—O5^i	142.42 (4)	C4—C5—H5	110.3 (13)
O3^i—K—O5^i	70.30 (4)	C6—C5—H5	110.9 (13)
O23^ii—K—O5^i	141.38 (4)	O6—C6—C5	107.03 (13)
O2^iii—K—O5^i	82.15 (4)	O6—C6—H6A	111.1 (11)
O6^iii—K—O5^i	72.30 (4)	C5—C6—H6A	111.1 (12)
O22—K—O21^iv	93.52 (4)	O6—C6—H6B	106.8 (13)
O3^i—K—O21^iv	79.86 (4)	C5—C6—H6B	111.2 (13)
O23^ii—K—O21^iv	93.87 (3)	H6A—C6—H6B	109.5 (18)
O2^iii—K—O21^iv	150.46 (4)	C1—O1—K	124.25 (11)
O6^iii—K—O21^iv	154.80 (4)	C2—O2—K^v	128.65 (10)
O5^i—K—O21^iv	98.99 (4)	C2—O2—H2O	111.5 (19)
O22—K—O1	66.75 (4)	K^v—O2—H2O	117.6 (19)
O3^i—K—O1	140.41 (4)	C3—O3—K^vi	131.24 (10)
O23^ii—K—O1	137.02 (4)	C3—O3—H3O	105.2 (19)
O2^iii—K—O1	131.13 (4)	K^vi—O3—H3O	110.0 (19)
O6^iii—K—O1	77.58 (4)	C1—O4—C4	111.14 (13)
O5^i—K—O1	81.47 (4)	C5—O5—K^vi	119.38 (10)
O21^iv—K—O1	77.75 (4)	C5—O5—H5O	107 (2)
O1—C1—O4	122.44 (16)	K^vi—O5—H5O	120 (2)
O1—C1—C2	126.35 (16)	C3—O6—C6	108.47 (13)
O4—C1—C2	111.20 (14)	C3—O6—K^v	123.35 (9)
O2—C2—C1	112.80 (14)	C6—O6—K^v	126.50 (10)
O2—C2—C3	112.01 (14)	O21—S2—O23	115.28 (8)
C1—C2—C3	100.35 (13)	O21—S2—O22	114.05 (8)
O2—C2—S2	111.76 (11)	O23—S2—O22	112.00 (7)
C1—C2—S2	106.78 (11)	O21—S2—C2	105.36 (7)
C3—C2—S2	112.53 (11)	O23—S2—C2	105.37 (7)
O3—C3—O6	113.20 (13)	O22—S2—C2	103.37 (7)
O3—C3—C4	111.05 (14)	S2—O21—K^vii	151.80 (7)
O6—C3—C4	103.23 (12)	S2—O22—K	146.08 (7)
O3—C3—C2	118.36 (13)	S2—O23—K^viii	133.30 (7)
O6—C3—C2	104.85 (13)	H8OA—O8—H8OB	104 (3)
C4—C3—C2	104.75 (13)	H9OA—O9—H9OB	105 (3)
O1—C1—C2—O2	40.4 (2)	C2—C3—O3—K^vi	−171.95 (10)
O4—C1—C2—O2	−138.58 (15)	O1—C1—O4—C4	−176.90 (16)
O1—C1—C2—C3	159.75 (17)	C2—C1—O4—C4	2.15 (18)
O4—C1—C2—C3	−19.25 (17)	C5—C4—O4—C1	127.76 (15)
O1—C1—C2—S2	−82.73 (19)	C3—C4—O4—C1	16.26 (17)
O4—C1—C2—S2	98.27 (14)	C4—C5—O5—K^vi	59.03 (16)
O2—C2—C3—O3	−87.94 (18)	C6—C5—O5—K^vi	−53.94 (16)
C1—C2—C3—O3	152.15 (14)	O3—C3—O6—C6	−84.25 (16)
S2—C2—C3—O3	38.98 (18)	C4—C3—O6—C6	35.89 (17)
O2—C2—C3—O6	39.38 (16)	C2—C3—O6—C6	145.34 (13)
C1—C2—C3—O6	−80.53 (14)	O3—C3—O6—K^v	81.84 (15)
S2—C2—C3—O6	166.30 (10)	C4—C3—O6—K^v	−158.02 (9)
O2—C2—C3—C4	147.71 (14)	C2—C3—O6—K^v	−48.57 (15)
C1—C2—C3—C4	27.80 (16)	C5—C6—O6—C3	−23.76 (18)
S2—C2—C3—C4	−85.37 (14)	C5—C6—O6—K^v	170.70 (10)
O3—C3—C4—O4	−156.62 (13)	O2—C2—S2—O21	−179.15 (11)
O6—C3—C4—O4	81.78 (14)	C1—C2—S2—O21	−55.36 (13)
C2—C3—C4—O4	−27.74 (16)	C3—C2—S2—O21	53.81 (13)
O3—C3—C4—C5	87.81 (16)	O2—C2—S2—O23	58.52 (13)
O6—C3—C4—C5	−33.79 (17)	C1—C2—S2—O23	−177.69 (11)
C2—C3—C4—C5	−143.31 (14)	C3—C2—S2—O23	−68.53 (12)
O4—C4—C5—O5	152.70 (14)	O2—C2—S2—O22	−59.16 (13)
C3—C4—C5—O5	−96.18 (16)	C1—C2—S2—O22	64.63 (12)
O4—C4—C5—C6	−91.63 (16)	C3—C2—S2—O22	173.79 (11)
C3—C4—C5—C6	19.50 (18)	O23—S2—O21—K^vii	−81.35 (17)
O5—C5—C6—O6	118.72 (15)	O22—S2—O21—K^vii	50.28 (18)
C4—C5—C6—O6	1.37 (18)	C2—S2—O21—K^vii	162.95 (15)
O4—C1—O1—K	−129.43 (14)	O21—S2—O22—K	67.79 (15)
C2—C1—O1—K	51.7 (2)	O23—S2—O22—K	−159.00 (12)
O22—K—O1—C1	−10.21 (13)	C2—S2—O22—K	−46.05 (15)
O3^i—K—O1—C1	−166.47 (13)	O3^i—K—O22—S2	170.05 (11)
O23^ii—K—O1—C1	−27.09 (16)	O23^ii—K—O22—S2	−173.73 (14)
O2^iii—K—O1—C1	77.60 (15)	O2^iii—K—O22—S2	−110.99 (14)
O6^iii—K—O1—C1	75.65 (14)	O6^iii—K—O22—S2	−61.82 (14)
O5^i—K—O1—C1	149.28 (14)	O5^i—K—O22—S2	−16.32 (18)
O21^iv—K—O1—C1	−109.51 (14)	O21^iv—K—O22—S2	93.35 (14)
C1—C2—O2—K^v	93.66 (15)	O1—K—O22—S2	18.29 (13)
C3—C2—O2—K^v	−18.67 (18)	O21—S2—O23—K^viii	98.09 (10)
S2—C2—O2—K^v	−146.01 (8)	O22—S2—O23—K^viii	−34.51 (11)
O6—C3—O3—K^vi	64.81 (18)	C2—S2—O23—K^viii	−146.21 (9)
C4—C3—O3—K^vi	−50.77 (18)

Symmetry codes: (i) x−1, y−1, z; (ii) x−1/2, −y+1/2, −z+1; (iii) x, y−1, z; (iv) x−1, y, z; (v) x, y+1, z; (vi) x+1, y+1, z; (vii) x+1, y, z; (viii) x+1/2, −y+1/2, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2O···O8^ix	0.77 (3)	1.91 (3)	2.6533 (18)	162 (3)
O3—H3O···O8	0.79 (3)	1.87 (3)	2.6525 (18)	171 (3)
O5—H5O···O9^x	0.70 (3)	2.01 (3)	2.684 (2)	162 (3)
O8—H8OA···O22^v	0.81 (3)	2.07 (3)	2.8141 (18)	155 (3)
O8—H8OB···O23^ix	0.78 (3)	2.13 (3)	2.7798 (18)	142 (2)
O9—H9OA···O5^i	0.77 (3)	2.13 (3)	2.869 (2)	161 (3)
O9—H9OB···O1	0.83 (3)	1.95 (3)	2.7852 (19)	175 (3)

Symmetry codes: (i) x−1, y−1, z; (v) x, y+1, z; (ix) x−1/2, −y+3/2, −z+1; (x) −x+2, y+1/2, −z+3/2.