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ISSN: 2056-9890

5-Amino-7-(4-bromo­phen­yl)-3,7-di­hydro-2H-thieno[3,2-b]pyran-6-carbo­nitrile 1,1-dioxide

aSchool of Chemistry and Chemical Engineering, Xuzhou Normal University, Xuzhou 221116, People's Republic of China, and, Key Laboratory of Biotechnology for Medicinal Plants, Xuzhou Normal University, Xuzhou 221116, People's Republic of China
*Correspondence e-mail: chshengyaonk@mail.nankai.edu.cn

(Received 16 November 2009; accepted 23 December 2009; online 9 January 2010)

In the title compound, C14H11BrN2O3S, the 2,3-dihydro­thio­phene ring is almost planar [maximum deviation = 0.006 (1) Å]. The pyran ring is in an envelope conformation [puckering parameters Q = 0.115 (2) Å, θ = 77.5 (10), φ = 172.9 (10)°]. The pyran and phenyl rings are approximately perpendicular, making a dihedral angle of −76.4 (2)°. The crystal packing is stabilized by inter­molecular N—H⋯O hydrogen bonds, with the sulfone O atoms acting as acceptors.

Related literature

For the use of thienopyranyl compounds, such as thieno[3,2-b]pyran derivatives, as anti­viral agents, see: Friary et al. (1991[Friary, R. J., Schwerdt, J. H. & Ganguly, A. K. (1991). US Patent No. 5034531.]) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009[Chao, J. H., Zheng, J. Y. & Aslanian, R. G. (2009). WO Patent No. 2009020578.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C14H11BrN2O3S

  • Mr = 367.22

  • Monoclinic, P 21 /c

  • a = 8.3743 (18) Å

  • b = 14.003 (3) Å

  • c = 12.673 (3) Å

  • β = 103.059 (3)°

  • V = 1447.7 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 2.99 mm−1

  • T = 113 K

  • 0.24 × 0.22 × 0.12 mm

Data collection
  • Rigaku Saturn CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.]) Tmin = 0.534, Tmax = 0.715

  • 14473 measured reflections

  • 3440 independent reflections

  • 2636 reflections with I > 2σ(I)

  • Rint = 0.038

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.088

  • S = 0.99

  • 3440 reflections

  • 198 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.95 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H1⋯O2i 0.88 (3) 2.26 (3) 2.989 (3) 140 (2)
N2—H2⋯O3ii 0.91 (3) 2.02 (3) 2.919 (3) 169 (2)
Symmetry codes: (i) -x+2, -y+2, -z+1; (ii) x+1, y, z.

Data collection: CrystalClear (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, can be used as antiviral agents (Friary et al., 1991) and α-2 C adrenoreceptor agonists (Chao et al., 2009). This led us to pay much attention to the synthesis and bioactivity of these compounds. During the synthesis of thieno[3,2-b]pyran derivatives, the title compound, (I) was isolated and its structure was determined by X-ray diffraction. Here we shall report its crystal structure.

The molecular structure of (I) is shown in Fig. 1. In the molecular structure, the thiophene ring is in planar conformation, for the maximum deviation of C6 from the C4/C5/C6/C7/S1 plane is 0.006 (1) Å. For its weighted average ABS. torsion Angl. is 0.60°, less than 5.0°, Cremer & Pople puckering analysis was not performed(Cremer & Pople, 1975). The pyran ring adopts an envelope conformation with atome C3 deviating from the O1/C1/C2/C4/C5 plane 0.158 (3) Å. According to Cremer & Pople analysis, the puckering amplitude (Q) is 0.115 (2) Å. Its θ and φ are 77.5 (10) and 172.9 (10)°, respectively. The connection of the pyran ring and phenyl ring C8—C13 can be described by the C2—C3—C8—C13 torsion angle of -76.4 (2)°. The crystal packing is stablized intermolecular hydrogen bonds: N2—H1···O2, N2—H2···O3(Fig.2 & Table 1).

Related literature top

For the use of thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, as antiviral agents, see: Friary et al. (1991) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was synthesized by the reaction of dihydrothiophen-3(2H)-one-1,1-dioxide (1 mmol) and 2-(4-bromo benzylidene)malononitrile (1 mmol) catalyzed by triethylamine (0.02 g) in 10 ml ethanol under reluxing until completion (monitored by TLC). Cooling the reaction mixture slowly gave single crystals suitable for X-ray diffraction.

Refinement top

The H atoms bonded to the amide N atom was located in a difference map and were refined freely. Other H atoms were placed in calculated positions, with C—H = 0.95 or 0.99 Å, and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq(parent atom).

Structure description top

Thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, can be used as antiviral agents (Friary et al., 1991) and α-2 C adrenoreceptor agonists (Chao et al., 2009). This led us to pay much attention to the synthesis and bioactivity of these compounds. During the synthesis of thieno[3,2-b]pyran derivatives, the title compound, (I) was isolated and its structure was determined by X-ray diffraction. Here we shall report its crystal structure.

The molecular structure of (I) is shown in Fig. 1. In the molecular structure, the thiophene ring is in planar conformation, for the maximum deviation of C6 from the C4/C5/C6/C7/S1 plane is 0.006 (1) Å. For its weighted average ABS. torsion Angl. is 0.60°, less than 5.0°, Cremer & Pople puckering analysis was not performed(Cremer & Pople, 1975). The pyran ring adopts an envelope conformation with atome C3 deviating from the O1/C1/C2/C4/C5 plane 0.158 (3) Å. According to Cremer & Pople analysis, the puckering amplitude (Q) is 0.115 (2) Å. Its θ and φ are 77.5 (10) and 172.9 (10)°, respectively. The connection of the pyran ring and phenyl ring C8—C13 can be described by the C2—C3—C8—C13 torsion angle of -76.4 (2)°. The crystal packing is stablized intermolecular hydrogen bonds: N2—H1···O2, N2—H2···O3(Fig.2 & Table 1).

For the use of thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, as antiviral agents, see: Friary et al. (1991) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009). For puckering parameters, see: Cremer & Pople (1975).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The packing diagram of (I). Intermolecular hydrogen bonds are shown as dashed lines.
5-Amino-7-(4-bromophenyl)-3,7-dihydro-2H- thieno[3,2-b]pyran-6-carbonitrile 1,1-dioxide top
Crystal data top
C14H11BrN2O3SF(000) = 736
Mr = 367.22Dx = 1.685 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71070 Å
a = 8.3743 (18) ÅCell parameters from 4061 reflections
b = 14.003 (3) Åθ = 2.2–27.9°
c = 12.673 (3) ŵ = 2.99 mm1
β = 103.059 (3)°T = 113 K
V = 1447.7 (5) Å3Block, colorless
Z = 40.24 × 0.22 × 0.12 mm
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
3440 independent reflections
Radiation source: rotating anode2636 reflections with I > 2σ(I)
Confocal monochromatorRint = 0.038
Detector resolution: 7.31 pixels mm-1θmax = 27.9°, θmin = 2.2°
ω and φ scansh = 1010
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
k = 1818
Tmin = 0.534, Tmax = 0.715l = 1616
14473 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 0.99 w = 1/[σ2(Fo2) + (0.053P)2]
where P = (Fo2 + 2Fc2)/3
3440 reflections(Δ/σ)max = 0.002
198 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = 0.95 e Å3
Crystal data top
C14H11BrN2O3SV = 1447.7 (5) Å3
Mr = 367.22Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.3743 (18) ŵ = 2.99 mm1
b = 14.003 (3) ÅT = 113 K
c = 12.673 (3) Å0.24 × 0.22 × 0.12 mm
β = 103.059 (3)°
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
3440 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
2636 reflections with I > 2σ(I)
Tmin = 0.534, Tmax = 0.715Rint = 0.038
14473 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 0.99Δρmax = 0.43 e Å3
3440 reflectionsΔρmin = 0.95 e Å3
198 parameters
Special details top

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) top
xyzUiso*/Ueq
Br10.66967 (3)1.11722 (2)1.066878 (18)0.03931 (11)
S10.65228 (6)0.83655 (4)0.56887 (4)0.01756 (13)
O11.12195 (16)0.86398 (10)0.63555 (11)0.0190 (3)
O20.56187 (19)0.87395 (11)0.46675 (13)0.0269 (4)
O30.56402 (17)0.83246 (11)0.65464 (12)0.0248 (4)
N11.1137 (2)1.20266 (14)0.67001 (15)0.0277 (4)
N21.3147 (2)0.97623 (16)0.66289 (15)0.0231 (4)
C11.1535 (2)0.95981 (16)0.64815 (15)0.0181 (4)
C21.0334 (2)1.02597 (15)0.64622 (15)0.0164 (4)
C30.8526 (2)1.00119 (14)0.63725 (15)0.0161 (4)
H30.78421.03810.57580.019*
C40.8376 (2)0.89711 (14)0.61035 (16)0.0159 (4)
C50.9603 (2)0.83720 (15)0.61122 (15)0.0158 (4)
C60.9284 (2)0.73518 (15)0.58117 (16)0.0187 (4)
H6A0.97760.69320.64290.022*
H6B0.97610.71850.51890.022*
C70.7412 (2)0.72300 (15)0.55110 (18)0.0237 (5)
H7A0.70680.67460.59840.028*
H7B0.70500.70170.47500.028*
C80.7996 (2)1.02716 (15)0.74159 (15)0.0165 (4)
C90.7130 (2)1.11041 (14)0.74657 (17)0.0189 (4)
H90.68121.14910.68380.023*
C100.6716 (3)1.13834 (17)0.84266 (17)0.0229 (5)
H100.61221.19570.84600.027*
C110.7190 (2)1.08054 (17)0.93298 (16)0.0217 (5)
C120.8041 (3)0.99677 (16)0.92947 (16)0.0227 (5)
H120.83460.95790.99220.027*
C130.8450 (2)0.96971 (15)0.83348 (16)0.0206 (5)
H130.90370.91210.83040.025*
C151.0788 (3)1.12338 (16)0.65907 (16)0.0186 (4)
H11.349 (3)1.035 (2)0.655 (2)0.038 (7)*
H21.382 (3)0.925 (2)0.659 (2)0.038 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.03575 (17)0.0621 (2)0.02199 (14)0.01328 (12)0.01055 (11)0.00769 (11)
S10.0142 (3)0.0163 (3)0.0212 (3)0.0009 (2)0.0022 (2)0.0001 (2)
O10.0143 (7)0.0179 (8)0.0251 (8)0.0003 (6)0.0051 (6)0.0008 (6)
O20.0224 (8)0.0267 (9)0.0271 (9)0.0035 (6)0.0042 (7)0.0044 (7)
O30.0206 (8)0.0226 (9)0.0341 (9)0.0026 (7)0.0121 (7)0.0002 (7)
N10.0360 (11)0.0233 (11)0.0261 (10)0.0079 (9)0.0119 (8)0.0034 (8)
N20.0150 (9)0.0235 (11)0.0325 (11)0.0019 (9)0.0089 (8)0.0004 (9)
C10.0185 (10)0.0226 (12)0.0133 (9)0.0038 (9)0.0037 (8)0.0007 (8)
C20.0178 (10)0.0174 (11)0.0148 (9)0.0032 (8)0.0054 (8)0.0011 (8)
C30.0144 (10)0.0173 (11)0.0163 (9)0.0010 (8)0.0028 (8)0.0001 (8)
C40.0172 (10)0.0164 (11)0.0144 (9)0.0015 (8)0.0042 (8)0.0004 (8)
C50.0134 (9)0.0186 (11)0.0154 (10)0.0001 (8)0.0030 (8)0.0003 (8)
C60.0183 (10)0.0188 (11)0.0195 (10)0.0012 (9)0.0055 (8)0.0012 (8)
C70.0198 (11)0.0182 (12)0.0327 (12)0.0015 (9)0.0052 (9)0.0055 (9)
C80.0139 (9)0.0174 (11)0.0182 (10)0.0025 (8)0.0038 (8)0.0009 (8)
C90.0142 (10)0.0202 (12)0.0207 (10)0.0014 (8)0.0006 (8)0.0011 (8)
C100.0186 (10)0.0239 (12)0.0254 (12)0.0063 (9)0.0036 (9)0.0042 (9)
C110.0176 (10)0.0303 (13)0.0183 (10)0.0013 (9)0.0062 (8)0.0048 (9)
C120.0269 (11)0.0210 (12)0.0208 (10)0.0010 (9)0.0069 (9)0.0035 (9)
C130.0245 (11)0.0159 (11)0.0222 (11)0.0051 (9)0.0071 (9)0.0040 (8)
C150.0180 (10)0.0243 (13)0.0146 (10)0.0017 (9)0.0060 (8)0.0010 (8)
Geometric parameters (Å, º) top
Br1—C111.905 (2)C4—C51.324 (3)
S1—O21.4421 (16)C5—C61.487 (3)
S1—O31.4470 (15)C6—C71.537 (3)
S1—C41.742 (2)C6—H6A0.9900
S1—C71.791 (2)C6—H6B0.9900
O1—C11.370 (3)C7—H7A0.9900
O1—C51.371 (2)C7—H7B0.9900
N1—C151.148 (3)C8—C91.382 (3)
N2—C11.340 (3)C8—C131.396 (3)
N2—H10.88 (3)C9—C101.395 (3)
N2—H20.91 (3)C9—H90.9500
C1—C21.364 (3)C10—C111.385 (3)
C2—C151.416 (3)C10—H100.9500
C2—C31.532 (3)C11—C121.379 (3)
C3—C41.496 (3)C12—C131.389 (3)
C3—C81.531 (3)C12—H120.9500
C3—H31.0000C13—H130.9500
O2—S1—O3115.77 (10)C7—C6—H6A110.4
O2—S1—C4110.20 (10)C5—C6—H6B110.4
O3—S1—C4111.35 (9)C7—C6—H6B110.4
O2—S1—C7111.00 (10)H6A—C6—H6B108.6
O3—S1—C7110.89 (10)C6—C7—S1107.46 (14)
C4—S1—C795.89 (9)C6—C7—H7A110.2
C1—O1—C5116.68 (16)S1—C7—H7A110.2
C1—N2—H1119.2 (17)C6—C7—H7B110.2
C1—N2—H2117.9 (17)S1—C7—H7B110.2
H1—N2—H2120 (2)H7A—C7—H7B108.5
N2—C1—C2127.0 (2)C9—C8—C13119.66 (18)
N2—C1—O1110.25 (18)C9—C8—C3119.83 (18)
C2—C1—O1122.75 (18)C13—C8—C3120.44 (18)
C1—C2—C15118.32 (18)C8—C9—C10120.9 (2)
C1—C2—C3124.07 (19)C8—C9—H9119.6
C15—C2—C3117.53 (17)C10—C9—H9119.6
C4—C3—C8113.76 (16)C11—C10—C9118.4 (2)
C4—C3—C2105.54 (16)C11—C10—H10120.8
C8—C3—C2110.88 (15)C9—C10—H10120.8
C4—C3—H3108.8C12—C11—C10121.63 (19)
C8—C3—H3108.8C12—C11—Br1118.42 (16)
C2—C3—H3108.8C10—C11—Br1119.95 (17)
C5—C4—C3126.21 (19)C11—C12—C13119.48 (19)
C5—C4—S1109.30 (16)C11—C12—H12120.3
C3—C4—S1124.47 (15)C13—C12—H12120.3
C4—C5—O1123.58 (19)C12—C13—C8119.9 (2)
C4—C5—C6120.83 (18)C12—C13—H13120.0
O1—C5—C6115.56 (17)C8—C13—H13120.0
C5—C6—C7106.51 (16)N1—C15—C2179.0 (2)
C5—C6—H6A110.4
C5—O1—C1—N2175.02 (16)C1—O1—C5—C47.0 (3)
C5—O1—C1—C25.5 (3)C1—O1—C5—C6170.86 (16)
N2—C1—C2—C151.2 (3)C4—C5—C6—C71.2 (3)
O1—C1—C2—C15179.45 (17)O1—C5—C6—C7176.74 (16)
N2—C1—C2—C3175.30 (19)C5—C6—C7—S10.9 (2)
O1—C1—C2—C34.1 (3)O2—S1—C7—C6114.83 (15)
C1—C2—C3—C410.6 (2)O3—S1—C7—C6115.01 (14)
C15—C2—C3—C4172.93 (17)C4—S1—C7—C60.54 (16)
C1—C2—C3—C8113.0 (2)C4—C3—C8—C9140.68 (18)
C15—C2—C3—C863.5 (2)C2—C3—C8—C9100.6 (2)
C8—C3—C4—C5112.4 (2)C4—C3—C8—C1342.4 (2)
C2—C3—C4—C59.4 (3)C2—C3—C8—C1376.4 (2)
C8—C3—C4—S169.5 (2)C13—C8—C9—C100.6 (3)
C2—C3—C4—S1168.70 (14)C3—C8—C9—C10176.30 (18)
O2—S1—C4—C5114.85 (15)C8—C9—C10—C110.1 (3)
O3—S1—C4—C5115.27 (15)C9—C10—C11—C120.5 (3)
C7—S1—C4—C50.10 (17)C9—C10—C11—Br1178.53 (15)
O2—S1—C4—C363.5 (2)C10—C11—C12—C130.6 (3)
O3—S1—C4—C366.35 (19)Br1—C11—C12—C13178.44 (16)
C7—S1—C4—C3178.48 (17)C11—C12—C13—C80.1 (3)
C3—C4—C5—O11.4 (3)C9—C8—C13—C120.5 (3)
S1—C4—C5—O1176.96 (14)C3—C8—C13—C12176.40 (18)
C3—C4—C5—C6179.15 (18)C1—C2—C15—N1156 (15)
S1—C4—C5—C60.8 (2)C3—C2—C15—N121 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H1···O2i0.88 (3)2.26 (3)2.989 (3)140 (2)
N2—H2···O3ii0.91 (3)2.02 (3)2.919 (3)169 (2)
Symmetry codes: (i) x+2, y+2, z+1; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC14H11BrN2O3S
Mr367.22
Crystal system, space groupMonoclinic, P21/c
Temperature (K)113
a, b, c (Å)8.3743 (18), 14.003 (3), 12.673 (3)
β (°) 103.059 (3)
V3)1447.7 (5)
Z4
Radiation typeMo Kα
µ (mm1)2.99
Crystal size (mm)0.24 × 0.22 × 0.12
Data collection
DiffractometerRigaku Saturn CCD area-detector
Absorption correctionMulti-scan
(CrystalClear; Rigaku/MSC, 2005)
Tmin, Tmax0.534, 0.715
No. of measured, independent and
observed [I > 2σ(I)] reflections
14473, 3440, 2636
Rint0.038
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.088, 0.99
No. of reflections3440
No. of parameters198
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.43, 0.95

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H1···O2i0.88 (3)2.26 (3)2.989 (3)140 (2)
N2—H2···O3ii0.91 (3)2.02 (3)2.919 (3)169 (2)
Symmetry codes: (i) x+2, y+2, z+1; (ii) x+1, y, z.
 

Acknowledgements

The authors acknowledge financial support by the Graduate Foundation of Xuzhou Normal University (No. 09YLB030).

References

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First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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