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Acta Crystallogr Sect E Struct Rep Online. 2010 February 1; 66(Pt 2): o388.
Published online 2010 January 16. doi:  10.1107/S1600536810001315
PMCID: PMC2979899

Ethyl (2S,4R)-4-(4-bromo­phen­yl)-2-hydr­oxy-5,10-dioxo-3,4,5,10-tetra­hydro-2H-benzo[g]chromene-2-carboxyl­ate

Abstract

In the crystal structure of the title compound, C22H17BrO6, the quinone ring makes a dihedral angle of 81.84 (3)° with the benzene ring. The chiral C atoms, viz. the ring C atoms bearing the hydr­oxy and bromo­phenyl substituents, exhibit R and S configurations, respectively. The terminal ethyl group of the –CO2CH2CH3 group is disordered over two sets of sites with site-occupancy factors of 0.64 (1) and 0.36 (1). Inter­molecular O—H(...)O inter­actions further stabilize the crystal packing.

Related literature

For general background to the modification of hydroxyquinone, see: Rueping et al. (2008 [triangle]); Zhou et al. (2008 [triangle]). For related structures, see: Peng (2006 [triangle]); Nasiri et al. (2008 [triangle]).

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Object name is e-66-0o388-scheme1.jpg

Experimental

Crystal data

  • C22H17BrO6
  • M r = 457.27
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o388-efi1.jpg
  • a = 8.2993 (6) Å
  • b = 9.9445 (7) Å
  • c = 12.4884 (10) Å
  • β = 96.323 (2)°
  • V = 1024.43 (13) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 2.04 mm−1
  • T = 296 K
  • 0.32 × 0.30 × 0.28 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995 [triangle]) T min = 0.520, T max = 0.565
  • 9887 measured reflections
  • 4549 independent reflections
  • 2257 reflections with I > 2σ(I)
  • R int = 0.036

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.122
  • S = 1.00
  • 4549 reflections
  • 273 parameters
  • 3 restraints
  • H-atom parameters constrained
  • Δρmax = 0.30 e Å−3
  • Δρmin = −0.37 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 2082 Friedel pairs
  • Flack parameter: −0.008 (11)

Data collection: PROCESS-AUTO (Rigaku, 2006 [triangle]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku, 2007 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810001315/zq2026sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810001315/zq2026Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

We thank Professor Jian-Ming Gu, Zhejiang University, for his help.

supplementary crystallographic information

Comment

The Michael addition to α, β-unsaturated systems is an important carbon-carbon bond-forming reaction in organic synthesis. Hydroxyquinones, quinones bearing a hydroxy group on the quinone ring, are an important class of the naturally occurring quinones with diverse biological activity. The title compound, ethyl (2S,4R)-4-(4-bromophenyl)-2-hydroxy-5,10-dioxo-3,4,5,10-tetrahydro-2H-benzo[g]chromene-2-carboxylate, was synthesized from a Michael Addition of 2-hydroxy-1,4-naphthoquinone to β,γ-unsaturated α-keto esters. The crystal structure of the title compound (Fig. 1) contains a tricyclic ring system with two chiral centers, which is consisting of a quinone ring and a tetrahydropyrane. One carbon atom of the tetrahydropyrane structure is not coplanar with the backbone, lying 0.554 (4) Å from the mean plane of the rest backbone. The terminal ethyl group of CO2CH2CH3 is disordered over two sites with site occupancy factors of 0.64 (1) and 0.36 (1). Moreover, weak O-H···O and C-H···O intermolecular interactions further stabilize the crystal structure.

Experimental

To a solution of (E)-ethyl 4-(4-bromophenyl)-2-oxobut-3-enoate (1 mmol) and 2-hydroxy-1,4-naphthoquinone (1 mmol) in 1,4-dioxane (3 ml) was added 3-((1S)-(6-methoxyquinolin-4-yl) (8-vinylquinuclidin-2-yl)methylamino)-4- ((S)-1-phenylethylamino)cyclobut -3-ene-1,2-dione (0.025 mmol) as catalyst, and the mixture was stirred at room temperature for 12 h (monitored by TLC). Then the solvent was distilled under vacuum, and the residue was purified by flash column chromatography (silica gel, Hex/AcOEt, v/v, 3:1) giving the title compound. Single crystals were obtained by slow evaporation of an ethyl acetate solution.

Refinement

H atoms were placed in calculated positions with C—H = 0.98 Å (sp), C—H = 0.97 (1) Å (sp2), C—H = 0.96 (1) Å (sp3), C—H = 0.93 (1) Å (aromatic) and Uiso(H) = 1.2Ueq of the carrier carbon atoms. There is a positional disorder of the terminal ethyl group of CO2CH2CH3, the corresponding atoms C21 and C22 were split into two sites with refined site occupancy factors of 0.64 (1) and 0.36 (1).

Figures

Fig. 1.
Molecular structure of the title compound, with the atomic labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
Crystal packing of the title compound showing O—H···O interactions (symmetry code i = x+1, y, z).

Crystal data

C22H17BrO6F(000) = 464
Mr = 457.27Dx = 1.482 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 6026 reflections
a = 8.2993 (6) Åθ = 3.1–27.4°
b = 9.9445 (7) ŵ = 2.04 mm1
c = 12.4884 (10) ÅT = 296 K
β = 96.323 (2)°Block, yellow
V = 1024.43 (13) Å30.32 × 0.30 × 0.28 mm
Z = 2

Data collection

Rigaku R-AXIS RAPID diffractometer4549 independent reflections
Radiation source: rolling anode2257 reflections with I > 2σ(I)
graphiteRint = 0.036
Detector resolution: 10.00 pixels mm-1θmax = 27.4°, θmin = 3.1°
ω scansh = −10→9
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)k = −12→12
Tmin = 0.520, Tmax = 0.565l = −16→16
9887 measured reflections

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.037w = 1/[σ2(Fo2) + (0.0455P)2 + 0.125P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.122(Δ/σ)max < 0.001
S = 1.00Δρmax = 0.30 e Å3
4549 reflectionsΔρmin = −0.37 e Å3
273 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
3 restraintsExtinction coefficient: 0.032 (3)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 2082 Friedel pairs
Secondary atom site location: difference Fourier mapFlack parameter: −0.008 (11)

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 (Å2)

xyzUiso*/UeqOcc. (<1)
Br10.33160 (10)0.08140 (7)0.99547 (5)0.1284 (4)
O20.4425 (4)0.3938 (3)0.2686 (3)0.0777 (8)
O30.5431 (3)0.4731 (3)0.4648 (2)0.0672 (7)
O10.0040 (4)0.4443 (3)0.5476 (3)0.0859 (10)
O50.6613 (4)0.2659 (3)0.5810 (3)0.0889 (10)
C90.1656 (5)0.3695 (4)0.2984 (4)0.0611 (10)
O40.7341 (3)0.5933 (3)0.5658 (3)0.0775 (8)
H40.81670.55020.55930.093*
C10.3205 (5)0.5027 (4)0.6295 (3)0.0570 (10)
H10.23900.56950.64430.068*
O60.7358 (5)0.3924 (4)0.7236 (3)0.1036 (12)
C110.3827 (5)0.4427 (4)0.4456 (3)0.0538 (10)
C120.6071 (5)0.5058 (4)0.5745 (4)0.0606 (10)
C40.0525 (5)0.3817 (4)0.3718 (3)0.0590 (10)
C20.2738 (5)0.4529 (4)0.5170 (3)0.0531 (9)
C140.3196 (4)0.3945 (4)0.7159 (3)0.0569 (10)
C150.3232 (6)0.4341 (4)0.8218 (4)0.0771 (13)
H150.32190.52550.83750.093*
C130.4825 (4)0.5773 (5)0.6336 (3)0.0615 (9)
H13A0.46330.66600.60250.074*
H13B0.52610.58900.70830.074*
C80.1163 (7)0.3247 (5)0.1949 (4)0.0797 (13)
H80.19220.31350.14610.096*
C7−0.0437 (7)0.2971 (5)0.1644 (4)0.0874 (15)
H7−0.07580.26880.09430.105*
C190.3191 (5)0.2591 (4)0.6952 (4)0.0629 (11)
H190.31510.22950.62430.076*
C30.1041 (5)0.4276 (4)0.4823 (4)0.0630 (11)
C100.3394 (5)0.4014 (4)0.3315 (4)0.0618 (11)
C200.6695 (5)0.3722 (5)0.6254 (4)0.0685 (11)
C5−0.1090 (5)0.3531 (4)0.3391 (4)0.0707 (11)
H5−0.18520.36270.38790.085*
C6−0.1585 (6)0.3107 (5)0.2360 (4)0.0795 (14)
H6−0.26700.29150.21480.095*
C160.3287 (6)0.3430 (5)0.9056 (4)0.0887 (14)
H160.33340.37230.97660.106*
C180.3245 (5)0.1658 (4)0.7774 (4)0.0755 (13)
H180.32640.07440.76160.091*
C170.3270 (6)0.2071 (5)0.8817 (4)0.0789 (13)
C21A0.8604 (17)0.2834 (14)0.7646 (12)0.132 (5)0.640 (10)
H21A0.86980.21380.71120.159*0.640 (10)
H21B0.96650.32150.78680.159*0.640 (10)
C22A0.7845 (17)0.2353 (15)0.8537 (12)0.147 (4)0.640 (10)
H22A0.85930.18000.89830.221*0.640 (10)
H22B0.69070.18330.82800.221*0.640 (10)
H22C0.75230.31010.89500.221*0.640 (10)
C21B0.763 (3)0.2550 (18)0.780 (3)0.132 (5)0.360 (10)
H21C0.67310.23000.81940.159*0.360 (10)
H21D0.78290.18400.72970.159*0.360 (10)
C22B0.903 (3)0.289 (3)0.849 (2)0.147 (4)0.360 (10)
H22D0.88420.27390.92240.221*0.360 (10)
H22E0.92940.38190.83920.221*0.360 (10)
H22F0.99240.23390.83220.221*0.360 (10)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.2086 (8)0.0939 (4)0.0809 (4)0.0050 (5)0.0071 (4)0.0256 (3)
O20.0728 (19)0.096 (2)0.068 (2)−0.0024 (17)0.0246 (16)−0.0008 (16)
O30.0554 (17)0.0802 (18)0.067 (2)−0.0018 (14)0.0092 (14)0.0006 (15)
O10.0552 (17)0.128 (3)0.075 (2)0.0008 (16)0.0111 (17)−0.0089 (19)
O50.094 (2)0.0616 (19)0.109 (3)0.0086 (17)0.005 (2)−0.0157 (18)
C90.063 (3)0.062 (2)0.057 (3)−0.002 (2)0.002 (2)0.0062 (19)
O40.0591 (16)0.0631 (16)0.110 (2)−0.0151 (15)0.0098 (17)0.004 (2)
C10.060 (2)0.051 (2)0.061 (3)0.0031 (18)0.011 (2)−0.0041 (18)
O60.132 (3)0.079 (2)0.091 (3)0.025 (2)−0.027 (2)0.006 (2)
C110.054 (2)0.052 (2)0.056 (3)0.0022 (16)0.006 (2)0.0052 (17)
C120.055 (2)0.058 (2)0.067 (3)−0.0071 (19)0.002 (2)−0.0010 (19)
C40.051 (2)0.062 (2)0.062 (3)−0.0003 (18)0.000 (2)0.0078 (19)
C20.042 (2)0.055 (2)0.062 (3)0.0040 (16)0.0023 (19)0.0026 (17)
C140.062 (2)0.053 (2)0.055 (3)−0.0003 (19)0.0055 (19)−0.0066 (18)
C150.118 (4)0.053 (2)0.062 (3)−0.006 (2)0.016 (3)−0.004 (2)
C130.063 (2)0.0481 (18)0.073 (3)−0.001 (2)0.0057 (19)0.001 (2)
C80.092 (4)0.094 (3)0.053 (3)−0.003 (3)0.009 (3)0.001 (2)
C70.091 (4)0.103 (4)0.063 (3)−0.008 (3)−0.013 (3)−0.005 (3)
C190.071 (3)0.058 (2)0.060 (3)−0.0003 (19)0.009 (2)−0.0053 (19)
C30.060 (3)0.064 (2)0.066 (3)0.0035 (18)0.010 (2)−0.0004 (19)
C100.063 (3)0.057 (2)0.066 (3)−0.002 (2)0.013 (2)0.010 (2)
C200.062 (3)0.065 (3)0.077 (3)0.004 (2)0.002 (2)0.000 (2)
C50.062 (3)0.077 (3)0.073 (3)−0.006 (2)0.007 (2)0.002 (2)
C60.077 (3)0.082 (3)0.076 (4)−0.007 (2)−0.006 (3)0.003 (3)
C160.126 (4)0.085 (3)0.056 (3)0.002 (3)0.014 (3)−0.012 (2)
C180.093 (4)0.057 (3)0.075 (3)−0.003 (2)0.005 (3)−0.001 (2)
C170.097 (4)0.073 (3)0.065 (3)0.004 (2)0.004 (3)−0.005 (2)
C21A0.160 (14)0.136 (8)0.092 (7)−0.003 (9)−0.021 (10)0.026 (7)
C22A0.133 (10)0.180 (12)0.129 (9)−0.002 (9)0.013 (9)0.027 (9)
C21B0.160 (14)0.136 (8)0.092 (7)−0.003 (9)−0.021 (10)0.026 (7)
C22B0.133 (10)0.180 (12)0.129 (9)−0.002 (9)0.013 (9)0.027 (9)

Geometric parameters (Å, °)

Br1—C171.889 (5)C15—H150.9300
O2—C101.226 (5)C13—H13A0.9700
O3—C111.360 (5)C13—H13B0.9700
O3—C121.451 (5)C8—C71.368 (7)
O1—C31.238 (5)C8—H80.9300
O5—C201.192 (5)C7—C61.384 (7)
C9—C81.386 (6)C7—H70.9300
C9—C41.387 (6)C19—C181.381 (6)
C9—C101.490 (6)C19—H190.9300
O4—C121.380 (5)C5—C61.374 (7)
O4—H40.8200C5—H50.9300
C1—C21.500 (5)C6—H60.9300
C1—C141.524 (6)C16—C171.383 (6)
C1—C131.531 (5)C16—H160.9300
C1—H10.9800C18—C171.364 (6)
O6—C201.304 (5)C18—H180.9300
O6—C21B1.541 (12)C21A—C22A1.420 (13)
O6—C21A1.546 (11)C21A—H21A0.9700
C11—C21.341 (6)C21A—H21B0.9700
C11—C101.489 (6)C22A—H22A0.9600
C12—C131.513 (6)C22A—H22B0.9600
C12—C201.538 (6)C22A—H22C0.9600
C4—C51.387 (6)C21B—C22B1.415 (14)
C4—C31.472 (6)C21B—H21C0.9700
C2—C31.450 (6)C21B—H21D0.9700
C14—C191.371 (5)C22B—H22D0.9600
C14—C151.377 (6)C22B—H22E0.9600
C15—C161.381 (6)C22B—H22F0.9600
C11—O3—C12117.8 (3)C14—C19—C18121.4 (4)
C8—C9—C4119.5 (4)C14—C19—H19119.3
C8—C9—C10120.3 (4)C18—C19—H19119.3
C4—C9—C10120.2 (4)O1—C3—C2118.7 (4)
C12—O4—H4109.5O1—C3—C4120.9 (4)
C2—C1—C14114.1 (3)C2—C3—C4120.5 (4)
C2—C1—C13109.0 (3)O2—C10—C11121.2 (4)
C14—C1—C13113.0 (3)O2—C10—C9122.1 (4)
C2—C1—H1106.7C11—C10—C9116.6 (4)
C14—C1—H1106.7O5—C20—O6124.8 (4)
C13—C1—H1106.7O5—C20—C12125.1 (4)
C20—O6—C21B108.5 (11)O6—C20—C12110.1 (4)
C20—O6—C21A113.7 (7)C6—C5—C4121.2 (4)
C2—C11—O3125.7 (4)C6—C5—H5119.4
C2—C11—C10123.2 (4)C4—C5—H5119.4
O3—C11—C10111.0 (3)C5—C6—C7118.7 (5)
O4—C12—O3105.7 (3)C5—C6—H6120.7
O4—C12—C13108.1 (3)C7—C6—H6120.7
O3—C12—C13111.6 (3)C15—C16—C17118.6 (4)
O4—C12—C20110.6 (3)C15—C16—H16120.7
O3—C12—C20105.5 (3)C17—C16—H16120.7
C13—C12—C20114.9 (4)C17—C18—C19120.2 (4)
C9—C4—C5119.4 (4)C17—C18—H18119.9
C9—C4—C3119.9 (4)C19—C18—H18119.9
C5—C4—C3120.8 (4)C18—C17—C16119.9 (4)
C11—C2—C3119.4 (4)C18—C17—Br1121.0 (4)
C11—C2—C1121.6 (3)C16—C17—Br1119.0 (4)
C3—C2—C1118.7 (4)C22A—C21A—O699.0 (10)
C19—C14—C15117.5 (4)C22A—C21A—H21A112.0
C19—C14—C1124.0 (4)O6—C21A—H21A112.0
C15—C14—C1118.5 (3)C22A—C21A—H21B112.0
C14—C15—C16122.4 (4)O6—C21A—H21B112.0
C14—C15—H15118.8H21A—C21A—H21B109.6
C16—C15—H15118.8C22B—C21B—O697.8 (16)
C12—C13—C1113.6 (3)C22B—C21B—H21C112.2
C12—C13—H13A108.8O6—C21B—H21C112.2
C1—C13—H13A108.8C22B—C21B—H21D112.2
C12—C13—H13B108.8O6—C21B—H21D112.2
C1—C13—H13B108.8H21C—C21B—H21D109.8
H13A—C13—H13B107.7C21B—C22B—H22D109.5
C7—C8—C9120.1 (5)C21B—C22B—H22E109.5
C7—C8—H8120.0H22D—C22B—H22E109.5
C9—C8—H8120.0C21B—C22B—H22F109.5
C8—C7—C6121.1 (5)H22D—C22B—H22F109.5
C8—C7—H7119.4H22E—C22B—H22F109.5
C6—C7—H7119.4
C12—O3—C11—C27.0 (5)C9—C4—C3—O1177.1 (4)
C12—O3—C11—C10−175.6 (3)C5—C4—C3—O1−1.6 (6)
C11—O3—C12—O4−150.5 (3)C9—C4—C3—C2−3.5 (5)
C11—O3—C12—C13−33.2 (4)C5—C4—C3—C2177.9 (4)
C11—O3—C12—C2092.3 (4)C2—C11—C10—O2179.7 (4)
C8—C9—C4—C5−2.1 (6)O3—C11—C10—O22.2 (5)
C10—C9—C4—C5179.3 (4)C2—C11—C10—C9−0.5 (5)
C8—C9—C4—C3179.2 (4)O3—C11—C10—C9−178.1 (3)
C10—C9—C4—C30.6 (5)C8—C9—C10—O22.5 (6)
O3—C11—C2—C3174.9 (3)C4—C9—C10—O2−178.8 (4)
C10—C11—C2—C3−2.3 (5)C8—C9—C10—C11−177.3 (4)
O3—C11—C2—C10.8 (6)C4—C9—C10—C111.4 (5)
C10—C11—C2—C1−176.3 (3)C21B—O6—C20—O5−13.4 (15)
C14—C1—C2—C11−109.5 (4)C21A—O6—C20—O522.5 (9)
C13—C1—C2—C1118.0 (5)C21B—O6—C20—C12167.8 (14)
C14—C1—C2—C376.5 (4)C21A—O6—C20—C12−156.2 (7)
C13—C1—C2—C3−156.1 (3)O4—C12—C20—O5−115.1 (5)
C2—C1—C14—C1916.4 (5)O3—C12—C20—O5−1.3 (5)
C13—C1—C14—C19−108.9 (4)C13—C12—C20—O5122.1 (5)
C2—C1—C14—C15−165.1 (4)O4—C12—C20—O663.6 (5)
C13—C1—C14—C1569.5 (5)O3—C12—C20—O6177.5 (4)
C19—C14—C15—C161.0 (7)C13—C12—C20—O6−59.2 (5)
C1—C14—C15—C16−177.6 (4)C9—C4—C5—C61.1 (6)
O4—C12—C13—C1168.5 (3)C3—C4—C5—C6179.8 (4)
O3—C12—C13—C152.7 (4)C4—C5—C6—C7−0.2 (7)
C20—C12—C13—C1−67.4 (4)C8—C7—C6—C50.2 (8)
C2—C1—C13—C12−44.0 (4)C14—C15—C16—C17−1.4 (8)
C14—C1—C13—C1284.1 (4)C14—C19—C18—C171.4 (7)
C4—C9—C8—C72.1 (7)C19—C18—C17—C16−1.8 (7)
C10—C9—C8—C7−179.2 (4)C19—C18—C17—Br1179.2 (3)
C9—C8—C7—C6−1.2 (8)C15—C16—C17—C181.8 (8)
C15—C14—C19—C18−0.9 (6)C15—C16—C17—Br1−179.2 (4)
C1—C14—C19—C18177.5 (4)C20—O6—C21A—C22A−119.4 (11)
C11—C2—C3—O1−176.2 (4)C21B—O6—C21A—C22A−31 (2)
C1—C2—C3—O1−2.0 (5)C20—O6—C21B—C22B149 (2)
C11—C2—C3—C44.3 (5)C21A—O6—C21B—C22B43.5 (16)
C1—C2—C3—C4178.5 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O4—H4···O1i0.821.902.716 (4)177

Symmetry codes: (i) x+1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: ZQ2026).

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