Hexaaqua­nickel(II) bis­(4′,7-dimethoxy­isoflavone-3′-sulfonate) octa­hydrate

In the title compound, [Ni(H₂O)₆](C₁₇H₁₃O₇S)₂·8H₂O, the Ni^II atom is located on an inversion centre in the space group P2₁/c. The [Ni(H₂O)₆]²⁺, C₁₇H₁₃O₇S⁻ and H₂O components form many hydrogen bonds and there are π–π stacking inter­actions betweeen the isoflavone units. The hydrogen bonds, π–π stacking inter­actions and electrostatic inter­actions between the cation and anions link the components into a three-dimensional structure.

S1. Comment

Daidzein (4',7-dihydroxyisoflavone) is one of the effective principals of soy isoflavone. It has been pharmacologically shown to be antidysrhythmic (Fan et al., 1985) and antioxidant (Meng et al., 1999; Tikkanen et al., 1998), to remove hyperkinesias (Guo et al., 1995), to inhibit the growth of cancer cells (Jing & Han, 1992; Sathyamoorthy & Wang, 1997; Jing et al., 1993), to accelerate the formation of bone cells (Emi & Masayoshi, 2000) and to mimic a female hormone (Miksicek, 1993). Because the solubility of daidzein is poor, its biological utilization rate is low (Tang et al., 1989). Thus, it is necessary to synthesize a water-soluble derivative of daidzein in order to study its possible biological effects. We have synthesized several derivatives of daidzein, namely sodium 7-methoxy-4'-hydroxyisoflavone-3'-sulfonate (Zhang et al., 2002), sodium 4',7-dihydroxyisoflavone-3'-sulfonate (Zhang et al., 2003) and sodium 5,7-dihydroxy-4',6-dimethoxyisoflavone-3'-sulfonate (Zhang et al., 2004), and have studied their crystal structures and biological activities. The results showed that they possess better biological activities than daidzein. The title compound, (I), is a water-soluble derivative of daidzein with potential medical applications, and we report its crystal structure here.

Compound (I) consists of an [Ni(H₂O)₆]²⁺ cation, two C₁₇H₁₃O₄SO₃⁻ sulfonate anions and eight lattice water molecules (Fig. 1)·The Ni^II atom lies on an inversion centre and is coordinated by six water molecules which form a slightly distorted octahedron, in which the average Ni—O bond length is 2.0541 Å. In the C₁₇H₁₃O₄SO₃⁻ anion, the bond lengths and angles of the isoflavone skeleton are similar to those in magnesium 7-methoxy-4'-hydroxyisoflavone-3'-sulfonate (Zhang et al., 2003) and in cobalt 7-methoxy-4'-hydroxyisoflavone-3'-sulfonate (Zhang et al., 2002). The atoms in the benzopyranone moiety are nearly coplanar, as the dihedral angle between ring A (C4–C9) and ring C (C1–C4/C9/O1) is only 1.6°. To avoid steric conflict, the two rigid ring systems, namely phenyl ring B (C10–C15) and the benzopyranone moiety, are rotated by 56.5° with respect to each other. The methoxy group at atom C7 is nearly coplanar with the benzopyranone moiety, as indicated by the C16—O3—C7—C8 torsion angle of 2.7°. The methoxy group at atom C13 is also nearly coplanar with the attached ring, the C17—O4—C13—C14 torsion angle being 1.7°.

The sulfate (–SO₃), carbonyl (–C═O) and methoxy (–OCH₃) substituents of the isoflavone units, the eight lattice water molecules and the six coordinated water molecules are linked by hydrogen bonds (Table 1, Fig 1). Atoms H20 and H19 from the coordinated water molecules, as donors, form hydrogen bonds with two O atoms (O5 and O6) of the sulfate group of the isoflavone skeleton, which can be observed for the hydrogen bonds O10—H20···O5 and O8—H19···O6. Two hydrogen-bond chains exist between the isoflavone skeleton and the coordinated water molecules, bridged by the lattice water molecules O11 and O12, and O13 and O14, respectively. Each chain contains three hydrogen bonds, O11—H24···O2, O12—H27···O11 and O9—H22···O12, and O13—H29···O4, O13—H28···O14 and O10—H21···O14. The hydrogen bonds O12—H26···O6 and O13—H29···O7 exist between the O atoms (O6 and O7) of the sulfate group of the isoflavone skeleton and the lattice water molecules O12 and O13, respectively. In the hydrogen bonds O13—H29···O7 and O13—H29···O4, atom H29, as donor, forms one tricentred hydrogen bond with atoms O7 and O4. Atom O6 acts as acceptor for atoms H19 and H26 to form another tricentred hydrogen bond, which includes the hydrogen bonds O8—H19···O6 and O12—H26···O6. The lattice water molecules O12 and O13 are involved in the formation of three hydrogen bonds. All these hydrogen bonds not only link the isoflavone skeletons, coordinated water molecules and lattice water molecules together, but also play very important roles in the formation, stability and crystallization of (I).

The isoflavone skeletons are arranged in an antiparallel fashion and π–π stacking interactions exist between their rings A (C4–C9), linking the isoflavone skeletons into a column along the b axis (Fig. 2). Rings A of the isoflavone skeleton stack with those of neighbouring isoflavone skeletons, with Cg···Cg# = 3.644 (2) Å and Cg···Cg* = 3.773 (2) Å, where Cg is the centroid of ring A at (x, y, z), and Cg# and Cg* are the centres of rings A of the neighbouring isoflavone skeletons at (2 − x, 2 − y, 2 − z) and (2 − x, 1 − y, 2 − z), respectively. The corresponding interplanar spacings are 3.540 (2) and 3.567 (2) Å. Both of the ring–centroid distances lie in the normal range of 3.3–3.8 Å (Janiak, 2000), indicative of π–π stacking interactions.

Finally, it is noteworthy that compound (I) has a special packing motif (Fig.3). The coordinated water molecules, sulfate group and carbonyl are all hydrophilic. The distance between them is short and the areas which are surrounded by them are filled with the lattice water molecules. Therefore, there are hydrogen-bond networks in these areas. Apart from the hydrogen bonds involved in Fig. 1, the hydrogen bond O8—H18···O11ⁱ exists between the coordinated and lattice water molecules, O9—H23···O5ⁱⁱ exists between the sulfate group of the isoflavone skeleton and the coordinated water molecule, and O11—H25···O13ⁱⁱⁱ, O14—H30···O13^iv and O14—H31···O12^v are all hydrogen bonds between the lattice water molecules (Table 1). By contrast, there are no hydrophilic groups or hydrogen bonds in the hydrophobic areas formed by the isoflavone moieties. In these hydrophobic areas, the isoflavone skeletons are arranged in an antiparallel fashion, and π–π stacking interactions exist between them. The sulfate group is an important bridge as a structural link between the hydrophilic and hydrophobic regions. The hydrogen bonds, π–π stacking interactions and electrostatic interactions between the cation [Ni(H₂O)₆]²⁺ cation and the C₁₇H₁₃O₄SO₃⁻ sulfonate anion lead to the formation of a three-dimensional supramolecular structure.

S2. Experimental

Dimethyl sulfate (6 ml) was added dropwise to a solution of daidzein (4 g) in NaOH (50 ml, 5%) with vigorous stirring. The mixture was stirred at room temperature for 3 h and a precipitate appeared. This was collected by filtration and washed with water until the pH of the filtrate was 7, giving 4',7-dimethoxylisoflavone (3.5 g). 4',7-Dimethoxylisoflavone (2 g) was slowly added to sulfuric acid (8 ml, 98%) and stirred at room temperature. After 1 h, it was poured into a saturated NaCl solution (60 ml) and a white precipitate formed. This precipitate was collected by filtration and washed with saturated NaCl solution until the pH value of the filtrate was 7. Finally, the precipitate was recrystallized from water to afford sodium 4',7-dimethoxyisoflavone-3'-sulfonate (2.7 g). Sodium 4',7-dimethoxylisoflavone-3'-sulfonate (1 g) was dissolved in water (10 ml) and then mixed with a saturated NiSO₄·7H₂O solution (5 ml). Crystals of the title compound were obtained after 24 h. Compound (I) was recrystallized from ethanol–water (1:3 (v/v) after 3 d at room temperature, yielding crystals suitable for single-crystal X-ray analysis.

S3. Refinement

H atoms bonded to O atoms were found in difference maps and refined as riding. H atoms bonded to C atoms were placed in calculated positions (C—H = 0.93–0.96 Å) and refined as riding, allowing for free rotation of the rigid methyl groups. U_iso(H) values were constrained to be 1.2U_eq(C,O), or 1.5U_eq(C) for methyl H atoms.

Computing details

Data collection: SMART (Bruker, 1999); cell refinement: SMART; data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1999); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Thin dashed lines indicate the O—H···O hydrogen bonds. For clarity, all H atoms of the isoflavone skeletons have been omitted.
	Fig. 2. The π–π stacking interactions in (I). For clarity, all H atoms of the isoflavone skeletons have been omitted. Atoms labelled with a hash (#) or an asterisk (*) are at the symmetry positions (2 − x, 2 − y, 2 − z) and (2 − x, 1 − y, 2 − z), respectively.
	Fig. 3. The unit-cell packing diagram of (I).

Hexaaquanickel(II) bis(4',7-dimethoxylisoflavone-3'-sulfonate) octahydrate

Crystal data

[Ni(H2O)6](C17H13O4O3S)2·8H2O	F(000) = 1084
Mr = 1033.60	Dx = 1.538 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5366 reflections
a = 18.472 (4) Å	θ = 2.4–27.9°
b = 7.3227 (15) Å	µ = 0.63 mm^−1
c = 18.247 (4) Å	T = 298 K
β = 115.293 (3)°	Prismatic, green
V = 2231.4 (8) Å^3	0.56 × 0.15 × 0.13 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	3930 independent reflections
Radiation source: fine-focus sealed tube	3164 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.026
ϕ and ω scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −21→16
Tmin = 0.721, Tmax = 0.923	k = −8→8
11337 measured reflections	l = −21→21

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.092	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ^2(Fo^2) + (0.0491P)^2 + 1.1606P] where P = (Fo^2 + 2Fc^2)/3
3930 reflections	(Δ/σ)max = 0.001
351 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.28 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
Ni1	0.5000	0.0000	0.5000	0.02926 (13)
O8	0.61866 (10)	−0.0050 (3)	0.57842 (11)	0.0416 (4)
O9	0.47970 (12)	0.1997 (3)	0.56790 (12)	0.0441 (4)
H18	0.6360 (17)	−0.064 (4)	0.6205 (18)	0.055 (9)*
H19	0.6546 (19)	0.080 (5)	0.5860 (17)	0.062 (9)*
H22	0.517 (2)	0.267 (5)	0.599 (2)	0.091 (13)*
H23	0.442 (2)	0.269 (5)	0.542 (2)	0.076 (11)*
O1	1.05629 (9)	0.8234 (3)	0.88924 (9)	0.0431 (4)
O2	0.82401 (10)	0.6913 (3)	0.83461 (10)	0.0521 (5)
O3	1.12693 (11)	0.7767 (3)	1.17217 (10)	0.0550 (5)
O4	0.70265 (10)	0.7795 (2)	0.45826 (9)	0.0391 (4)
O5	0.61869 (10)	0.4999 (2)	0.50467 (11)	0.0440 (4)
O6	0.71703 (10)	0.3078 (2)	0.60392 (9)	0.0410 (4)
O7	0.72439 (11)	0.3713 (2)	0.47673 (10)	0.0452 (4)
S1	0.70164 (3)	0.43741 (8)	0.53829 (3)	0.03134 (15)
C1	0.99910 (14)	0.8166 (4)	0.81213 (13)	0.0397 (6)
H1	1.0147	0.8447	0.7713	0.048*
C2	0.92168 (13)	0.7731 (3)	0.78903 (13)	0.0333 (5)
C3	0.89402 (13)	0.7304 (3)	0.85089 (13)	0.0351 (5)
C4	0.95590 (13)	0.7411 (3)	0.93425 (13)	0.0341 (5)
C5	0.93809 (15)	0.7100 (4)	1.00061 (14)	0.0456 (6)
H5	0.8861	0.6800	0.9918	0.055*
C6	0.99625 (16)	0.7232 (4)	1.07804 (15)	0.0492 (7)
H6	0.9834	0.7029	1.1214	0.059*
C7	1.07493 (15)	0.7669 (3)	1.09262 (13)	0.0401 (6)
C8	1.09526 (14)	0.7990 (3)	1.02890 (13)	0.0383 (6)
H8	1.1475	0.8274	1.0379	0.046*
C9	1.03391 (13)	0.7867 (3)	0.95047 (13)	0.0335 (5)
C10	0.86384 (13)	0.7767 (3)	0.70214 (13)	0.0313 (5)
C11	0.81630 (12)	0.6251 (3)	0.66491 (12)	0.0305 (5)
H11	0.8209	0.5194	0.6949	0.037*
C12	0.76261 (12)	0.6303 (3)	0.58421 (12)	0.0283 (5)
C13	0.75580 (12)	0.7878 (3)	0.53766 (12)	0.0294 (5)
C14	0.80173 (13)	0.9401 (3)	0.57464 (13)	0.0324 (5)
H14	0.7972	1.0460	0.5449	0.039*
C15	0.85407 (13)	0.9337 (3)	0.65568 (14)	0.0350 (5)
H15	0.8837	1.0372	0.6801	0.042*
C16	1.20881 (17)	0.8153 (5)	1.19178 (16)	0.0610 (8)
H16A	1.2389	0.8182	1.2496	0.091*
H16B	1.2127	0.9317	1.1695	0.091*
H16C	1.2300	0.7221	1.1694	0.091*
C17	0.69152 (17)	0.9398 (4)	0.40979 (14)	0.0453 (6)
H17A	0.6525	0.9157	0.3555	0.068*
H17B	0.7414	0.9733	0.4090	0.068*
H17C	0.6731	1.0380	0.4323	0.068*
O11	0.67001 (13)	0.7863 (3)	0.71612 (11)	0.0491 (5)
O12	0.60921 (14)	0.4194 (4)	0.67790 (13)	0.0629 (6)
H24	0.718 (3)	0.763 (6)	0.742 (2)	0.095 (14)*
H25	0.6511 (19)	0.838 (5)	0.7477 (18)	0.065 (10)*
H26	0.644 (3)	0.376 (6)	0.661 (2)	0.102 (14)*
H27	0.613 (3)	0.546 (7)	0.677 (3)	0.115 (17)*
O13	0.61083 (14)	0.5442 (4)	0.31567 (14)	0.0674 (6)
O14	0.53902 (16)	0.2020 (3)	0.27865 (13)	0.0690 (6)
H28	0.610 (2)	0.420 (6)	0.301 (2)	0.087 (13)*
H29	0.642 (3)	0.526 (7)	0.369 (3)	0.15 (2)*
H30	0.4853 (13)	0.177 (6)	0.247 (2)	0.122 (17)*
H31	0.563 (3)	0.164 (8)	0.245 (3)	0.16 (2)*
O10	0.51971 (11)	0.1977 (3)	0.42963 (12)	0.0435 (4)
H20	0.536 (2)	0.290 (6)	0.450 (2)	0.090 (14)*
H21	0.524 (2)	0.166 (6)	0.385 (2)	0.102 (14)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.0266 (2)	0.0268 (2)	0.0323 (2)	−0.00109 (16)	0.01056 (17)	0.00014 (16)
O8	0.0285 (9)	0.0425 (11)	0.0443 (10)	−0.0046 (8)	0.0064 (8)	0.0102 (9)
O9	0.0388 (10)	0.0405 (11)	0.0465 (10)	0.0051 (9)	0.0119 (9)	−0.0092 (9)
O1	0.0306 (8)	0.0649 (12)	0.0337 (8)	−0.0092 (8)	0.0137 (7)	−0.0050 (8)
O2	0.0313 (9)	0.0798 (14)	0.0431 (10)	−0.0082 (9)	0.0138 (8)	0.0061 (9)
O3	0.0562 (11)	0.0679 (13)	0.0325 (9)	−0.0018 (10)	0.0109 (8)	−0.0024 (9)
O4	0.0479 (10)	0.0306 (9)	0.0306 (8)	−0.0044 (7)	0.0089 (7)	0.0030 (7)
O5	0.0319 (9)	0.0345 (10)	0.0567 (11)	−0.0037 (7)	0.0104 (8)	0.0007 (8)
O6	0.0467 (10)	0.0310 (9)	0.0397 (9)	−0.0075 (7)	0.0130 (8)	0.0038 (7)
O7	0.0582 (11)	0.0374 (10)	0.0443 (9)	−0.0049 (8)	0.0261 (8)	−0.0125 (8)
S1	0.0328 (3)	0.0248 (3)	0.0339 (3)	−0.0033 (2)	0.0119 (2)	−0.0016 (2)
C1	0.0365 (13)	0.0515 (16)	0.0305 (12)	−0.0045 (11)	0.0136 (10)	−0.0043 (10)
C2	0.0333 (12)	0.0324 (13)	0.0330 (11)	−0.0011 (10)	0.0130 (10)	−0.0034 (9)
C3	0.0324 (12)	0.0342 (13)	0.0391 (12)	0.0004 (10)	0.0158 (10)	0.0007 (10)
C4	0.0327 (12)	0.0335 (13)	0.0369 (12)	0.0000 (10)	0.0157 (10)	−0.0001 (10)
C5	0.0405 (14)	0.0581 (17)	0.0428 (14)	−0.0044 (12)	0.0221 (11)	0.0040 (12)
C6	0.0543 (16)	0.0605 (18)	0.0375 (13)	−0.0037 (14)	0.0240 (12)	0.0040 (12)
C7	0.0463 (14)	0.0372 (14)	0.0319 (12)	0.0013 (11)	0.0122 (11)	−0.0007 (10)
C8	0.0341 (12)	0.0403 (14)	0.0380 (12)	−0.0013 (11)	0.0129 (10)	−0.0040 (10)
C9	0.0357 (12)	0.0330 (13)	0.0354 (12)	−0.0008 (10)	0.0187 (10)	−0.0022 (10)
C10	0.0291 (11)	0.0333 (13)	0.0329 (11)	−0.0008 (10)	0.0144 (9)	−0.0030 (9)
C11	0.0327 (11)	0.0279 (12)	0.0316 (11)	0.0016 (10)	0.0144 (9)	0.0025 (9)
C12	0.0294 (11)	0.0256 (12)	0.0321 (11)	−0.0019 (9)	0.0152 (9)	−0.0037 (9)
C13	0.0295 (11)	0.0287 (12)	0.0315 (11)	0.0016 (9)	0.0147 (9)	−0.0003 (9)
C14	0.0363 (12)	0.0251 (11)	0.0383 (12)	−0.0009 (10)	0.0184 (10)	0.0010 (9)
C15	0.0335 (12)	0.0320 (12)	0.0407 (12)	−0.0065 (10)	0.0172 (10)	−0.0077 (10)
C16	0.0500 (17)	0.075 (2)	0.0415 (15)	0.0022 (15)	0.0039 (13)	−0.0097 (14)
C17	0.0562 (16)	0.0360 (14)	0.0378 (13)	0.0041 (12)	0.0144 (12)	0.0077 (11)
O11	0.0411 (11)	0.0621 (13)	0.0395 (10)	0.0039 (10)	0.0129 (9)	0.0033 (9)
O12	0.0638 (14)	0.0642 (16)	0.0706 (14)	−0.0108 (12)	0.0381 (12)	−0.0112 (12)
O13	0.0731 (15)	0.0766 (18)	0.0453 (12)	−0.0123 (13)	0.0184 (11)	0.0036 (11)
O14	0.0813 (17)	0.0704 (16)	0.0524 (12)	0.0003 (13)	0.0259 (12)	−0.0018 (11)
O10	0.0499 (11)	0.0394 (11)	0.0406 (10)	−0.0111 (9)	0.0188 (8)	0.0005 (8)

Geometric parameters (Å, º)

Ni1—O8^i	2.0427 (17)	C6—C7	1.398 (4)
Ni1—O8	2.0427 (17)	C6—H6	0.9300
Ni1—O9	2.0522 (18)	C7—C8	1.386 (3)
Ni1—O9^i	2.0522 (18)	C8—C9	1.398 (3)
Ni1—O10	2.0678 (18)	C8—H8	0.9300
Ni1—O10^i	2.0678 (18)	C10—C15	1.393 (3)
O8—H18	0.82 (3)	C10—C11	1.399 (3)
O8—H19	0.88 (3)	C11—C12	1.380 (3)
O9—H22	0.84 (4)	C11—H11	0.9300
O9—H23	0.83 (4)	C12—C13	1.405 (3)
O1—C1	1.352 (3)	C13—C14	1.389 (3)
O1—C9	1.373 (3)	C14—C15	1.379 (3)
O2—C3	1.230 (3)	C14—H14	0.9300
O3—C7	1.358 (3)	C15—H15	0.9300
O3—C16	1.426 (3)	C16—H16A	0.9600
O4—C13	1.361 (3)	C16—H16B	0.9600
O4—C17	1.431 (3)	C16—H16C	0.9600
O5—S1	1.4594 (18)	C17—H17A	0.9600
O6—S1	1.4580 (16)	C17—H17B	0.9600
O7—S1	1.4408 (17)	C17—H17C	0.9600
S1—C12	1.778 (2)	O11—H24	0.82 (4)
C1—C2	1.345 (3)	O11—H25	0.88 (3)
C1—H1	0.9300	O12—H26	0.87 (4)
C2—C3	1.458 (3)	O12—H27	0.93 (5)
C2—C10	1.486 (3)	O13—H28	0.94 (4)
C3—C4	1.463 (3)	O13—H29	0.90 (6)
C4—C9	1.383 (3)	O14—H30	0.928 (19)
C4—C5	1.402 (3)	O14—H31	0.94 (6)
C5—C6	1.365 (3)	O10—H20	0.77 (4)
C5—H5	0.9300	O10—H21	0.88 (4)
O8^i—Ni1—O8	180.00 (11)	C7—C6—H6	119.7
O8^i—Ni1—O9	89.54 (8)	O3—C7—C8	124.5 (2)
O8—Ni1—O9	90.46 (8)	O3—C7—C6	114.8 (2)
O8^i—Ni1—O9^i	90.46 (8)	C8—C7—C6	120.7 (2)
O8—Ni1—O9^i	89.54 (8)	C7—C8—C9	117.1 (2)
O9—Ni1—O9^i	180.0	C7—C8—H8	121.4
O8^i—Ni1—O10	88.48 (8)	C9—C8—H8	121.4
O8—Ni1—O10	91.52 (8)	O1—C9—C4	121.45 (19)
O9—Ni1—O10	90.12 (9)	O1—C9—C8	115.2 (2)
O9^i—Ni1—O10	89.88 (9)	C4—C9—C8	123.3 (2)
O8^i—Ni1—O10^i	91.52 (8)	C15—C10—C11	117.92 (19)
O8—Ni1—O10^i	88.48 (8)	C15—C10—C2	120.7 (2)
O9—Ni1—O10^i	89.88 (9)	C11—C10—C2	121.3 (2)
O9^i—Ni1—O10^i	90.12 (9)	C12—C11—C10	120.8 (2)
O10—Ni1—O10^i	180.0	C12—C11—H11	119.6
Ni1—O8—H18	123 (2)	C10—C11—H11	119.6
Ni1—O8—H19	128 (2)	C11—C12—C13	120.4 (2)
H18—O8—H19	105 (3)	C11—C12—S1	120.15 (17)
Ni1—O9—H22	121 (3)	C13—C12—S1	119.47 (16)
Ni1—O9—H23	114 (2)	O4—C13—C14	124.46 (19)
H22—O9—H23	106 (4)	O4—C13—C12	116.41 (19)
C1—O1—C9	117.81 (18)	C14—C13—C12	119.13 (19)
C7—O3—C16	118.0 (2)	C15—C14—C13	119.7 (2)
C13—O4—C17	118.01 (18)	C15—C14—H14	120.1
O7—S1—O6	113.72 (11)	C13—C14—H14	120.1
O7—S1—O5	112.40 (11)	C14—C15—C10	122.0 (2)
O6—S1—O5	110.52 (10)	C14—C15—H15	119.0
O7—S1—C12	107.29 (10)	C10—C15—H15	119.0
O6—S1—C12	105.57 (10)	O3—C16—H16A	109.5
O5—S1—C12	106.80 (10)	O3—C16—H16B	109.5
C2—C1—O1	126.0 (2)	H16A—C16—H16B	109.5
C2—C1—H1	117.0	O3—C16—H16C	109.5
O1—C1—H1	117.0	H16A—C16—H16C	109.5
C1—C2—C3	119.0 (2)	H16B—C16—H16C	109.5
C1—C2—C10	120.9 (2)	O4—C17—H17A	109.5
C3—C2—C10	119.99 (19)	O4—C17—H17B	109.5
O2—C3—C2	122.9 (2)	H17A—C17—H17B	109.5
O2—C3—C4	122.5 (2)	O4—C17—H17C	109.5
C2—C3—C4	114.64 (19)	H17A—C17—H17C	109.5
C9—C4—C5	117.5 (2)	H17B—C17—H17C	109.5
C9—C4—C3	121.0 (2)	H24—O11—H25	110 (3)
C5—C4—C3	121.5 (2)	H26—O12—H27	107 (4)
C6—C5—C4	120.7 (2)	H28—O13—H29	95 (4)
C6—C5—H5	119.6	H30—O14—H31	102 (4)
C4—C5—H5	119.6	Ni1—O10—H20	117 (3)
C5—C6—C7	120.5 (2)	Ni1—O10—H21	120 (3)
C5—C6—H6	119.7	H20—O10—H21	120 (4)
C9—O1—C1—C2	−1.5 (4)	C7—C8—C9—C4	−1.4 (4)
O1—C1—C2—C3	0.8 (4)	C1—C2—C10—C15	−55.0 (3)
O1—C1—C2—C10	177.9 (2)	C3—C2—C10—C15	122.1 (2)
C1—C2—C3—O2	179.2 (2)	C1—C2—C10—C11	126.5 (3)
C10—C2—C3—O2	2.1 (4)	C3—C2—C10—C11	−56.4 (3)
C1—C2—C3—C4	0.3 (3)	C15—C10—C11—C12	1.3 (3)
C10—C2—C3—C4	−176.8 (2)	C2—C10—C11—C12	179.8 (2)
O2—C3—C4—C9	−179.5 (2)	C10—C11—C12—C13	1.1 (3)
C2—C3—C4—C9	−0.6 (3)	C10—C11—C12—S1	−179.08 (16)
O2—C3—C4—C5	−1.1 (4)	O7—S1—C12—C11	−115.62 (18)
C2—C3—C4—C5	177.8 (2)	O6—S1—C12—C11	6.0 (2)
C9—C4—C5—C6	−0.5 (4)	O5—S1—C12—C11	123.65 (18)
C3—C4—C5—C6	−179.0 (2)	O7—S1—C12—C13	64.24 (19)
C4—C5—C6—C7	−0.4 (4)	O6—S1—C12—C13	−174.16 (17)
C16—O3—C7—C8	−2.7 (4)	O5—S1—C12—C13	−56.49 (19)
C16—O3—C7—C6	178.1 (3)	C17—O4—C13—C14	−1.7 (3)
C5—C6—C7—O3	179.7 (3)	C17—O4—C13—C12	177.3 (2)
C5—C6—C7—C8	0.5 (4)	C11—C12—C13—O4	178.63 (19)
O3—C7—C8—C9	−178.7 (2)	S1—C12—C13—O4	−1.2 (3)
C6—C7—C8—C9	0.4 (4)	C11—C12—C13—C14	−2.3 (3)
C1—O1—C9—C4	1.1 (3)	S1—C12—C13—C14	177.87 (16)
C1—O1—C9—C8	−178.9 (2)	O4—C13—C14—C15	−179.8 (2)
C5—C4—C9—O1	−178.6 (2)	C12—C13—C14—C15	1.1 (3)
C3—C4—C9—O1	−0.1 (4)	C13—C14—C15—C10	1.2 (3)
C5—C4—C9—C8	1.5 (4)	C11—C10—C15—C14	−2.4 (3)
C3—C4—C9—C8	179.9 (2)	C2—C10—C15—C14	179.0 (2)
C7—C8—C9—O1	178.6 (2)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O8—H18···O11^ii	0.82 (3)	1.93 (3)	2.741 (3)	176 (3)
O8—H19···O6	0.88 (3)	1.97 (4)	2.836 (3)	167 (3)
O9—H22···O12	0.84 (4)	2.03 (4)	2.870 (3)	178 (4)
O9—H23···O5^iii	0.83 (4)	2.01 (4)	2.800 (3)	161 (3)
O10—H20···O5	0.77 (4)	2.09 (4)	2.824 (3)	159 (4)
O10—H21···O14	0.88 (4)	2.10 (4)	2.925 (3)	158 (4)
O11—H24···O2	0.82 (4)	2.03 (4)	2.827 (3)	162 (4)
O11—H25···O13^iv	0.88 (3)	1.90 (3)	2.781 (3)	179 (3)
O12—H26···O6	0.87 (4)	2.10 (4)	2.959 (3)	169 (4)
O12—H27···O11	0.93 (5)	2.02 (5)	2.880 (3)	153 (4)
O13—H28···O14	0.94 (4)	1.99 (4)	2.780 (4)	140 (3)
O13—H29···O7	0.90 (6)	2.21 (6)	3.061 (3)	156 (5)
O13—H29···O4	0.90 (6)	2.41 (5)	2.974 (3)	121 (4)
O14—H30···O13^v	0.93 (2)	1.92 (2)	2.809 (4)	161 (4)
O14—H31···O12^vi	0.94 (6)	1.87 (6)	2.808 (3)	179 (5)

Symmetry codes: (ii) x, y−1, z; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z+1/2; (v) −x+1, y−1/2, −z+1/2; (vi) x, −y+1/2, z−1/2.