organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

5-(2-Chloro­benz­yl)-4,5,6,7-tetra­hydro­thieno[3,2-c]pyridin-2-yl acetate

aDepartment of Bioengineering, Tianjin Bohai Vocational, and Technical College, Tianjin 300408, People's Republic of China, and bTianjin Institute of Pharmaceutical Research, Tianjin 300193, People's Republic of China
*Correspondence e-mail: jingjing527@sina.com.cn

(Received 23 February 2012; accepted 7 March 2012; online 14 March 2012)

In the title compound, C16H16ClNO2S, the benzene and thio­phene rings make a dihedral angle of 72.60 (4)°. In the crystal, weak C—H⋯O inter­actions are observed.

Related literature

The title compound is a derivative of the anti­platelet agent clopidogrel [systematic name (+)-(S)-methyl 2-(2-chloro­phen­yl)-2-(6,7-dihydro­thieno[3,2-c]pyridin-5(4H)-yl)acetate]. For background to the bioactivity and applications of clopidogrel, see: Muller et al. (2003[Muller, I., Besta, F., Schulz, C., Li, Z., Massberg, S. & Gawaz, M. (2003). Circulation, 108, 2195-2197.]); Savi et al. (1994[Savi, P., Combalbert, J., Gaich, C., Rouchon, M. C., Maffrand, J. P., Berger, Y. & Herbert, J. M. (1994). Thromb. Haemost. 72, 313-317.]); Sharis et al. (1998[Sharis, P. J., Cannon, C. P. & Loscalzo, J. (1998). Ann. Intern. Med. 129, 394-405.]). For the synthesis of the title compound, see: Roquettes et al. (1993[Roquettes, B. A., Bordes, M. F., sur Seze, L., Toulouse, D. F., Herbert, J. M. & du Touch, P. (1993). US Patent No. 5 190 938.]).

[Scheme 1]

Experimental

Crystal data
  • C16H16ClNO2S

  • Mr = 321.81

  • Monoclinic, P 21 /n

  • a = 14.526 (3) Å

  • b = 6.1065 (12) Å

  • c = 17.490 (3) Å

  • β = 99.098 (3)°

  • V = 1532.0 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.39 mm−1

  • T = 113 K

  • 0.20 × 0.18 × 0.10 mm

Data collection
  • Rigaku Saturn CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]) Tmin = 0.926, Tmax = 0.962

  • 10686 measured reflections

  • 2704 independent reflections

  • 2397 reflections with I > 2σ(I)

  • Rint = 0.033

Refinement
  • R[F2 > 2σ(F2)] = 0.030

  • wR(F2) = 0.086

  • S = 1.07

  • 2704 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.31 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C15—H15⋯O1i 0.95 2.52 3.364 (2) 148
Symmetry code: (i) x+1, y, z.

Data collection: CrystalClear (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear and CrystalStructure. 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: CrystalStructure (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]).

Supporting information


Comment top

Clopidogrel is an oral, thienopyridine class of antiplatelet agent used to inhibit blood clots in coronary artery disease, peripheral vascular disease, and cerebrovascular disease (Muller et al., 2003; Savi et al., 1994; Sharis et al., 1998). The molecular structure of the title compound, a derivative of clopidogrel, is reported here. The thiophene and benzene rings make a dihedral angle of 72.60 (4)°; the tetrahydropyridine ring adopts a half-chair conformation (Fig. 1). In the crystal structure, the packing is realsied by weak intramolecular C—H···Cl and C—H···N, and intermolecular C—H···O interaction (Table 1).

Related literature top

The title compound is a derivative of the antiplatelet agent clopidogrel [systematic name (+)-(S)-methyl 2-(2-chlorophenyl)-2-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-yl)acetate] . For background to the bioactivity and applications of clopidogrel, see: Muller et al. (2003); Savi et al. (1994); Sharis et al. (1998). For the synthesis of the title compound, see: Roquettes et al. (1993).

Experimental top

We used the method of Roquettes et al. (1993) to sythesize the title compound. 8.85 g (0.0316 mol) of 5-(2-chlorobenzyl)-5,6,7,7a-tetrahydro-4H-thieno [3,2-c] pyridine-2-one are dissolved in 120 mL of isopropenyl acetate with 7.8 g (0.0411 mol) of p-toluenesulphonic acid; the medium is stirred at 363 K for 6 h. After cooling to about 293 K, 2 volumes of water are introduced into the medium, the pH is made basic by adding saturated aqueous NaHCO3 solution and the desired product is extracted with ethyl acetate. After removal of the solvent, the oil, dissolved in CH2Cl2, is filtered on silica to give a 68% yield of the target compound. Colourless single crystals were grown from a methanol solution.

Refinement top

All H atoms were positioned geometrically and refined using a riding model, with d(C—H) = 0.95 - 0.99 Å, and Uiso(H) = 1.5 or 1.2Ueq.

Structure description top

Clopidogrel is an oral, thienopyridine class of antiplatelet agent used to inhibit blood clots in coronary artery disease, peripheral vascular disease, and cerebrovascular disease (Muller et al., 2003; Savi et al., 1994; Sharis et al., 1998). The molecular structure of the title compound, a derivative of clopidogrel, is reported here. The thiophene and benzene rings make a dihedral angle of 72.60 (4)°; the tetrahydropyridine ring adopts a half-chair conformation (Fig. 1). In the crystal structure, the packing is realsied by weak intramolecular C—H···Cl and C—H···N, and intermolecular C—H···O interaction (Table 1).

The title compound is a derivative of the antiplatelet agent clopidogrel [systematic name (+)-(S)-methyl 2-(2-chlorophenyl)-2-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-yl)acetate] . For background to the bioactivity and applications of clopidogrel, see: Muller et al. (2003); Savi et al. (1994); Sharis et al. (1998). For the synthesis of the title compound, see: Roquettes et al. (1993).

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: CrystalStructure (Rigaku/MSC, 2005).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with the atom-numbering scheme and 50% probability displacement ellipsoids.
5-(2-Chlorobenzyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridin-2-yl acetate top
Crystal data top
C16H16ClNO2SF(000) = 672
Mr = 321.81Dx = 1.395 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4955 reflections
a = 14.526 (3) Åθ = 1.7–27.9°
b = 6.1065 (12) ŵ = 0.39 mm1
c = 17.490 (3) ÅT = 113 K
β = 99.098 (3)°Prism, colourless
V = 1532.0 (5) Å30.20 × 0.18 × 0.10 mm
Z = 4
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2704 independent reflections
Radiation source: rotating anode2397 reflections with I > 2σ(I)
Multilayer monochromatorRint = 0.033
Detector resolution: 14.63 pixels mm-1θmax = 25.0°, θmin = 1.7°
ω and φ scansh = 1717
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
k = 75
Tmin = 0.926, Tmax = 0.962l = 2020
10686 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)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0514P)2 + 0.2496P]
where P = (Fo2 + 2Fc2)/3
2704 reflections(Δ/σ)max = 0.001
191 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.31 e Å3
Crystal data top
C16H16ClNO2SV = 1532.0 (5) Å3
Mr = 321.81Z = 4
Monoclinic, P21/nMo Kα radiation
a = 14.526 (3) ŵ = 0.39 mm1
b = 6.1065 (12) ÅT = 113 K
c = 17.490 (3) Å0.20 × 0.18 × 0.10 mm
β = 99.098 (3)°
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2704 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku/MSC, 2005)
2397 reflections with I > 2σ(I)
Tmin = 0.926, Tmax = 0.962Rint = 0.033
10686 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0300 restraints
wR(F2) = 0.086H-atom parameters constrained
S = 1.07Δρmax = 0.18 e Å3
2704 reflectionsΔρmin = 0.31 e Å3
191 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
Cl10.64701 (3)0.34141 (7)0.05214 (2)0.03277 (14)
S10.08191 (2)0.16665 (6)0.14645 (2)0.01970 (13)
O10.07808 (8)0.0621 (2)0.12690 (7)0.0350 (3)
O20.03009 (7)0.21624 (17)0.06530 (6)0.0227 (2)
N10.38577 (8)0.2952 (2)0.15330 (6)0.0197 (3)
C10.11190 (11)0.4038 (3)0.05983 (9)0.0262 (4)
H1A0.17100.40200.08020.039*
H1B0.07730.53730.07710.039*
H1C0.12450.40050.00310.039*
C20.05566 (10)0.2093 (3)0.08876 (8)0.0232 (3)
C30.09637 (10)0.0575 (2)0.08845 (8)0.0189 (3)
C40.18265 (10)0.0674 (2)0.06854 (8)0.0192 (3)
H40.20220.17760.03620.023*
C50.24081 (10)0.1077 (2)0.10193 (7)0.0180 (3)
C60.34116 (10)0.1424 (2)0.09400 (8)0.0209 (3)
H6A0.37450.00040.09940.025*
H6B0.34510.20170.04190.025*
C70.32906 (10)0.4937 (3)0.15410 (8)0.0212 (3)
H7A0.31320.55200.10080.025*
H7B0.36510.60700.18650.025*
C80.23974 (10)0.4424 (2)0.18630 (8)0.0205 (3)
H8A0.25430.41270.24260.025*
H8B0.19650.56860.17820.025*
C90.19592 (10)0.2454 (3)0.14461 (8)0.0187 (3)
C100.47954 (10)0.3512 (2)0.13892 (9)0.0243 (4)
H10A0.50170.48170.17010.029*
H10B0.47640.39020.08360.029*
C110.54919 (10)0.1683 (2)0.15836 (8)0.0199 (3)
C120.54030 (10)0.0141 (3)0.21553 (8)0.0245 (3)
H120.48740.02070.24120.029*
C130.60608 (11)0.1481 (3)0.23609 (9)0.0258 (4)
H130.59820.25050.27540.031*
C140.68378 (11)0.1607 (3)0.19890 (9)0.0264 (4)
H140.72890.27240.21250.032*
C150.69503 (11)0.0102 (3)0.14218 (8)0.0259 (4)
H150.74800.01720.11660.031*
C160.62835 (10)0.1509 (2)0.12296 (8)0.0208 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0313 (2)0.0369 (3)0.0341 (2)0.00271 (18)0.01724 (18)0.01129 (18)
S10.0156 (2)0.0234 (2)0.0206 (2)0.00371 (15)0.00426 (15)0.00402 (15)
O10.0202 (6)0.0410 (7)0.0459 (7)0.0015 (5)0.0117 (5)0.0193 (6)
O20.0158 (5)0.0253 (6)0.0273 (5)0.0010 (4)0.0048 (4)0.0066 (5)
N10.0158 (6)0.0185 (6)0.0250 (7)0.0012 (5)0.0039 (5)0.0012 (5)
C10.0193 (8)0.0292 (9)0.0295 (8)0.0003 (7)0.0019 (6)0.0017 (7)
C20.0144 (7)0.0307 (9)0.0240 (7)0.0029 (7)0.0017 (6)0.0001 (7)
C30.0178 (7)0.0210 (8)0.0176 (7)0.0025 (6)0.0014 (5)0.0023 (6)
C40.0187 (8)0.0201 (8)0.0189 (7)0.0054 (6)0.0031 (6)0.0010 (6)
C50.0177 (7)0.0200 (7)0.0161 (7)0.0043 (6)0.0021 (5)0.0027 (6)
C60.0197 (8)0.0215 (8)0.0224 (7)0.0032 (6)0.0061 (6)0.0005 (6)
C70.0229 (8)0.0185 (8)0.0223 (7)0.0012 (6)0.0042 (6)0.0007 (6)
C80.0206 (8)0.0211 (8)0.0206 (7)0.0024 (6)0.0057 (6)0.0016 (6)
C90.0155 (7)0.0226 (8)0.0178 (7)0.0027 (6)0.0028 (5)0.0015 (6)
C100.0180 (8)0.0233 (8)0.0325 (8)0.0011 (6)0.0063 (6)0.0047 (7)
C110.0166 (7)0.0210 (8)0.0212 (7)0.0030 (6)0.0003 (6)0.0018 (6)
C120.0206 (8)0.0282 (9)0.0256 (7)0.0031 (7)0.0069 (6)0.0022 (7)
C130.0265 (9)0.0251 (9)0.0251 (8)0.0022 (7)0.0019 (6)0.0048 (7)
C140.0219 (8)0.0252 (9)0.0302 (8)0.0046 (7)0.0015 (6)0.0015 (7)
C150.0199 (8)0.0315 (9)0.0268 (8)0.0018 (7)0.0047 (6)0.0036 (7)
C160.0212 (8)0.0227 (8)0.0187 (7)0.0045 (6)0.0038 (6)0.0003 (6)
Geometric parameters (Å, º) top
Cl1—C161.7515 (15)C7—C81.526 (2)
S1—C91.7298 (15)C7—H7A0.9900
S1—C31.7362 (14)C7—H7B0.9900
O1—C21.1946 (19)C8—C91.496 (2)
O2—C21.3722 (17)C8—H8A0.9900
O2—C31.3810 (18)C8—H8B0.9900
N1—C101.4641 (18)C10—C111.509 (2)
N1—C71.4671 (19)C10—H10A0.9900
N1—C61.4676 (19)C10—H10B0.9900
C1—C21.485 (2)C11—C161.393 (2)
C1—H1A0.9800C11—C121.394 (2)
C1—H1B0.9800C12—C131.384 (2)
C1—H1C0.9800C12—H120.9500
C3—C41.354 (2)C13—C141.391 (2)
C4—C51.429 (2)C13—H130.9500
C4—H40.9500C14—C151.381 (2)
C5—C91.358 (2)C14—H140.9500
C5—C61.501 (2)C15—C161.384 (2)
C6—H6A0.9900C15—H150.9500
C6—H6B0.9900
C9—S1—C390.21 (7)H7A—C7—H7B108.1
C2—O2—C3120.95 (12)C9—C8—C7107.84 (12)
C10—N1—C7110.35 (12)C9—C8—H8A110.1
C10—N1—C6110.24 (11)C7—C8—H8A110.1
C7—N1—C6110.26 (11)C9—C8—H8B110.1
C2—C1—H1A109.5C7—C8—H8B110.1
C2—C1—H1B109.5H8A—C8—H8B108.5
H1A—C1—H1B109.5C5—C9—C8124.19 (13)
C2—C1—H1C109.5C5—C9—S1112.48 (11)
H1A—C1—H1C109.5C8—C9—S1123.33 (11)
H1B—C1—H1C109.5N1—C10—C11113.41 (12)
O1—C2—O2122.06 (14)N1—C10—H10A108.9
O1—C2—C1127.46 (14)C11—C10—H10A108.9
O2—C2—C1110.48 (13)N1—C10—H10B108.9
C4—C3—O2121.60 (13)C11—C10—H10B108.9
C4—C3—S1112.82 (11)H10A—C10—H10B107.7
O2—C3—S1125.56 (10)C16—C11—C12116.34 (14)
C3—C4—C5111.90 (13)C16—C11—C10121.82 (13)
C3—C4—H4124.1C12—C11—C10121.76 (13)
C5—C4—H4124.1C13—C12—C11122.09 (14)
C9—C5—C4112.57 (13)C13—C12—H12119.0
C9—C5—C6121.40 (13)C11—C12—H12119.0
C4—C5—C6126.01 (13)C12—C13—C14119.74 (14)
N1—C6—C5110.56 (11)C12—C13—H13120.1
N1—C6—H6A109.5C14—C13—H13120.1
C5—C6—H6A109.5C15—C14—C13119.75 (15)
N1—C6—H6B109.5C15—C14—H14120.1
C5—C6—H6B109.5C13—C14—H14120.1
H6A—C6—H6B108.1C14—C15—C16119.31 (14)
N1—C7—C8110.19 (12)C14—C15—H15120.3
N1—C7—H7A109.6C16—C15—H15120.3
C8—C7—H7A109.6C15—C16—C11122.76 (14)
N1—C7—H7B109.6C15—C16—Cl1117.60 (12)
C8—C7—H7B109.6C11—C16—Cl1119.63 (12)
C3—O2—C2—O13.4 (2)C6—C5—C9—S1178.61 (10)
C3—O2—C2—C1176.85 (12)C7—C8—C9—C515.76 (19)
C2—O2—C3—C4177.09 (13)C7—C8—C9—S1164.89 (10)
C2—O2—C3—S11.09 (19)C3—S1—C9—C50.20 (11)
C9—S1—C3—C40.86 (11)C3—S1—C9—C8179.22 (12)
C9—S1—C3—O2177.46 (12)C7—N1—C10—C11164.39 (12)
O2—C3—C4—C5177.12 (12)C6—N1—C10—C1173.58 (15)
S1—C3—C4—C51.27 (15)N1—C10—C11—C16154.60 (13)
C3—C4—C5—C91.12 (17)N1—C10—C11—C1228.7 (2)
C3—C4—C5—C6177.91 (13)C16—C11—C12—C130.2 (2)
C10—N1—C6—C5172.40 (12)C10—C11—C12—C13177.04 (14)
C7—N1—C6—C550.32 (15)C11—C12—C13—C140.3 (2)
C9—C5—C6—N115.88 (18)C12—C13—C14—C150.5 (2)
C4—C5—C6—N1163.07 (12)C13—C14—C15—C160.2 (2)
C10—N1—C7—C8167.59 (12)C14—C15—C16—C110.2 (2)
C6—N1—C7—C870.39 (14)C14—C15—C16—Cl1178.66 (11)
N1—C7—C8—C949.62 (14)C12—C11—C16—C150.5 (2)
C4—C5—C9—C8179.88 (12)C10—C11—C16—C15177.29 (14)
C6—C5—C9—C80.8 (2)C12—C11—C16—Cl1178.42 (11)
C4—C5—C9—S10.47 (16)C10—C11—C16—Cl11.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10B···Cl10.992.643.0648 (16)106
C12—H12···N10.952.582.898 (2)100
C15—H15···O1i0.952.523.364 (2)148
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC16H16ClNO2S
Mr321.81
Crystal system, space groupMonoclinic, P21/n
Temperature (K)113
a, b, c (Å)14.526 (3), 6.1065 (12), 17.490 (3)
β (°) 99.098 (3)
V3)1532.0 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.39
Crystal size (mm)0.20 × 0.18 × 0.10
Data collection
DiffractometerRigaku Saturn CCD area-detector
Absorption correctionMulti-scan
(CrystalClear; Rigaku/MSC, 2005)
Tmin, Tmax0.926, 0.962
No. of measured, independent and
observed [I > 2σ(I)] reflections
10686, 2704, 2397
Rint0.033
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.086, 1.07
No. of reflections2704
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.31

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

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C15—H15···O1i0.952.523.364 (2)148.1
Symmetry code: (i) x+1, y, z.
 

Acknowledgements

The authors thank Mr Hai-Bin Song at Nankai University for the X-ray crystallographic determination and helpful suggestions.

References

First citationMuller, I., Besta, F., Schulz, C., Li, Z., Massberg, S. & Gawaz, M. (2003). Circulation, 108, 2195–2197.  Web of Science CrossRef PubMed Google Scholar
First citationRigaku/MSC (2005). CrystalClear and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.  Google Scholar
First citationRoquettes, B. A., Bordes, M. F., sur Seze, L., Toulouse, D. F., Herbert, J. M. & du Touch, P. (1993). US Patent No. 5 190 938.  Google Scholar
First citationSavi, P., Combalbert, J., Gaich, C., Rouchon, M. C., Maffrand, J. P., Berger, Y. & Herbert, J. M. (1994). Thromb. Haemost. 72, 313–317.  CAS PubMed Web of Science Google Scholar
First citationSharis, P. J., Cannon, C. P. & Loscalzo, J. (1998). Ann. Intern. Med. 129, 394–405.  Web of Science CrossRef CAS PubMed Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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