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

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ISSN: 2056-9890

1-Benzoyl-3-[4-(3-benzoyl­thio­ureido)phen­yl]thio­urea

aSchool of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, UKM 43600 Bangi Selangor, Malaysia
*Correspondence e-mail: mbkassim@ukm.my

(Received 2 November 2010; accepted 8 November 2010; online 13 November 2010)

The mol­ecule of the title compound, C22H18N4O2S2, lies across a crystallographic inversion centre. The mol­ecule adopts a syn–anti configuration with respect to the positions of the carbonyl groups and terminal phenyl rings relative to the thione S atom across the C—N bond. There are two intra­molecular N—H⋯O and C—H⋯S hydrogen bonds within each molecule, resulting in the formation of four six-membered S(6) rings. The central and terminal rings make a dihedral angle of 13.55 (15)°. In the crystal, mol­ecules are linked by inter­molecular C—H⋯S hydrogen bonds, forming R22(14) rings and resulting in zigzag chains.

Related literature

For related compounds and structural parameters, see: Hung et al. (2010[Hung, W. W., Hassan, I. N., Yamin, B. M. & Kassim, M. B. (2010). Acta Cryst. E66, o314.]), Thiam et al. (2008[Thiam, E. I., Diop, M., Gaye, M., Sall, A. S. & Barry, A. H. (2008). Acta Cryst. E64, o776.]); Arslan et al. (2004[Arslan, H., Flörke, U. & Külcü, N. (2004). Acta Chim. Slov. 51, 787-792.]); Yamin et al., (2003[Yamin, B. M. & Yusof, M. S. M. (2003). Acta Cryst. E59, o151-o152.]). For bond-length data, see: Allen et al. (197)[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]. For hydrogen-bond motifs, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C22H18N4O2S2

  • Mr = 434.52

  • Monoclinic, P 21 /n

  • a = 11.513 (4) Å

  • b = 4.5279 (16) Å

  • c = 20.209 (7) Å

  • β = 101.146 (7)°

  • V = 1033.6 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 298 K

  • 0.50 × 0.15 × 0.13 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.950, Tmax = 0.964

  • 6173 measured reflections

  • 2142 independent reflections

  • 1529 reflections with I > 2σ(I)

  • Rint = 0.040

Refinement
  • R[F2 > 2σ(F2)] = 0.063

  • wR(F2) = 0.171

  • S = 1.14

  • 2142 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O1 0.86 1.85 2.590 (3) 144
C11—H11⋯S1 0.93 2.56 3.215 (3) 128
C5—H5⋯S1i 0.93 2.84 3.567 (3) 136
Symmetry code: (i) -x, -y+1, -z+2.

Data collection: SMART (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). SADABS, SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]), ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON.

Supporting information


Comment top

The title compound (Fig. 1) is a benzoyl thiourea derivatives and analogous to 1,2-bis(N'-benzoylthioureido)benzene, (Thiam et al., 2008), except that the other thiourea moiety is located in para position of the centre benzene ring. It is also an isomer of 1,1'-Diphenyl-3,3'-(p-phenylenedicarbonyl)dithiourea which was reported perviously (Hung et al., 2010). The bond lengths and angles are in normal ranges (Allen et al., 1987). The C=O bond length of 1.227 (3)Å is longer than the average C=O bond length (1.200 Å) and comparable to that observed in N-benzoyl-N'-phenylthiourea (Yamin et al., 2003). The C—N bond lengths are in the range of 1.330 (3) Å-1.415 (3)Å which are shorter than the normal single C—N bond length (1.469 Å) indicating double bond character (Arslan et al. 2004) owing to the resonance effect at the carbonyl-thiourea moiety. The thiourea fragment (S1/O1/N1/C6/C7/C8) is planar with a maximum deviation from its mean plane of 0.044 (3)Å for C8 atom. The central and terminal phenyl rings are essentially planar. The two rings make dihedral angles of 2.19 (13)° and 12.24 (15)°, respectively, with the thiourea fragment and the dihedral angle between those two rings is 13.55 (15)°.

As in most of the benzoyl thiourea derivatives, N–H···O intramolecular hydrogen bonding lead to the formation of two six membered S(6) rings [Etter et al., 1990; Bernstein et al., 1995) namely, C7/N1/C8/N2/H2/O1 and C7i/N1i/C8i/N2i/H2Ai/O1i (Fig. 1, Table 1). There are also weak C-H···S intramolecular hydrogen bonds involving resulting in another two S(6) rings (C8/N2/C9/C11/H11/S1 and C8i/N2i/C9i/C11i/H11i/S1i). In the crystal structure, molecules are linked by intermolecular C–H···S hydrogen bonds (Table 1) building R22(14) rings (Etter et al., 1990; Bernstein et al., 1995) (Fig. 2). Owing to the fact that the molecule is organised around an inversion center, these rings extend on each side of the molecule to form azigzag chain.

Related literature top

For related compounds and structural parameters, see: Hung et al. (2010), Thiam et al. (2008); Arslan et al. (2004); Yamin et al., (2003). For bond-length data, see: Allen et al. (197). For hydrogen-bond motifs, see: Etter et al. (1990); Bernstein et al. (1995).

Experimental top

The title compound was synthesized according to previously reported method with some modification (Thiam et al. 2008). Benzoyl chloride (10 mmol) was added to ammonium thiocyanate solution (10 mmol) and the mixture was left to react to completion. A yellowish product was filtered and added to a 1,4-diaminobenzene (5 mmol) in acetone and left at a refluxing temperature for 5 h. Yellowish precipitate was formed and a slow evaporation of the DMF solution of the product gave a crystal suitable for X-ray diffraction (Yield:75%).

Refinement top

All H atoms attached to C and N were calculated and treated as riding on their parent atoms with C-H= 0.93Å and N-H= 0.86Å with Uiso=1.2Ueq (C, N).

Structure description top

The title compound (Fig. 1) is a benzoyl thiourea derivatives and analogous to 1,2-bis(N'-benzoylthioureido)benzene, (Thiam et al., 2008), except that the other thiourea moiety is located in para position of the centre benzene ring. It is also an isomer of 1,1'-Diphenyl-3,3'-(p-phenylenedicarbonyl)dithiourea which was reported perviously (Hung et al., 2010). The bond lengths and angles are in normal ranges (Allen et al., 1987). The C=O bond length of 1.227 (3)Å is longer than the average C=O bond length (1.200 Å) and comparable to that observed in N-benzoyl-N'-phenylthiourea (Yamin et al., 2003). The C—N bond lengths are in the range of 1.330 (3) Å-1.415 (3)Å which are shorter than the normal single C—N bond length (1.469 Å) indicating double bond character (Arslan et al. 2004) owing to the resonance effect at the carbonyl-thiourea moiety. The thiourea fragment (S1/O1/N1/C6/C7/C8) is planar with a maximum deviation from its mean plane of 0.044 (3)Å for C8 atom. The central and terminal phenyl rings are essentially planar. The two rings make dihedral angles of 2.19 (13)° and 12.24 (15)°, respectively, with the thiourea fragment and the dihedral angle between those two rings is 13.55 (15)°.

As in most of the benzoyl thiourea derivatives, N–H···O intramolecular hydrogen bonding lead to the formation of two six membered S(6) rings [Etter et al., 1990; Bernstein et al., 1995) namely, C7/N1/C8/N2/H2/O1 and C7i/N1i/C8i/N2i/H2Ai/O1i (Fig. 1, Table 1). There are also weak C-H···S intramolecular hydrogen bonds involving resulting in another two S(6) rings (C8/N2/C9/C11/H11/S1 and C8i/N2i/C9i/C11i/H11i/S1i). In the crystal structure, molecules are linked by intermolecular C–H···S hydrogen bonds (Table 1) building R22(14) rings (Etter et al., 1990; Bernstein et al., 1995) (Fig. 2). Owing to the fact that the molecule is organised around an inversion center, these rings extend on each side of the molecule to form azigzag chain.

For related compounds and structural parameters, see: Hung et al. (2010), Thiam et al. (2008); Arslan et al. (2004); Yamin et al., (2003). For bond-length data, see: Allen et al. (197). For hydrogen-bond motifs, see: Etter et al. (1990); Bernstein et al. (1995).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom labeling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii. H bonds are shown as dashed lines.[Symmetry code: (i) -x+1, -y+2, -z+2.]
[Figure 2] Fig. 2. Partial packing view down the b axis showing the formation of R22(14) graph set motifs. Hydrogen bonds are drawn as dashed lines. H atoms not involved in hydrogen bondings have been omitted for clarity. [Symmetry code: (ii) -x, -y+1, -z+2]
1-Benzoyl-3-[4-(3-benzoylthioureido)phenyl]thiourea top
Crystal data top
C22H18N4O2S2F(000) = 452
Mr = 434.52Dx = 1.396 Mg m3
Monoclinic, P21/nMelting point: 511 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 11.513 (4) ÅCell parameters from 1244 reflections
b = 4.5279 (16) Åθ = 1.9–26.5°
c = 20.209 (7) ŵ = 0.29 mm1
β = 101.146 (7)°T = 298 K
V = 1033.6 (6) Å3Needle, yellow
Z = 20.50 × 0.15 × 0.13 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2142 independent reflections
Radiation source: fine-focus sealed tube1529 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.040
ω scanθmax = 26.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1114
Tmin = 0.950, Tmax = 0.964k = 55
6173 measured reflectionsl = 2523
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)] = 0.063Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.171H-atom parameters constrained
S = 1.14 w = 1/[σ2(Fo2) + (0.0839P)2 + 0.1163P]
where P = (Fo2 + 2Fc2)/3
2142 reflections(Δ/σ)max = 0.001
136 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C22H18N4O2S2V = 1033.6 (6) Å3
Mr = 434.52Z = 2
Monoclinic, P21/nMo Kα radiation
a = 11.513 (4) ŵ = 0.29 mm1
b = 4.5279 (16) ÅT = 298 K
c = 20.209 (7) Å0.50 × 0.15 × 0.13 mm
β = 101.146 (7)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2142 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
1529 reflections with I > 2σ(I)
Tmin = 0.950, Tmax = 0.964Rint = 0.040
6173 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0630 restraints
wR(F2) = 0.171H-atom parameters constrained
S = 1.14Δρmax = 0.34 e Å3
2142 reflectionsΔρmin = 0.23 e Å3
136 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
S10.16597 (7)0.6404 (2)1.04023 (4)0.0663 (4)
O10.25185 (19)0.2798 (6)0.84661 (10)0.0637 (7)
N10.14062 (19)0.3425 (5)0.92651 (10)0.0425 (6)
H1A0.07670.28520.93880.051*
N20.30760 (19)0.6294 (5)0.94925 (11)0.0432 (6)
H2A0.31490.55460.91120.052*
C10.0805 (3)0.0367 (8)0.76267 (15)0.0643 (10)
H10.14540.03440.74640.077*
C20.0026 (4)0.2077 (10)0.72171 (17)0.0836 (13)
H20.00620.25060.67790.100*
C30.0988 (3)0.3159 (8)0.74552 (18)0.0709 (11)
H30.15570.42860.71760.085*
C40.1102 (3)0.2566 (8)0.81058 (16)0.0563 (8)
H40.17420.33230.82700.068*
C50.0271 (3)0.0849 (7)0.85172 (14)0.0465 (7)
H50.03520.04670.89580.056*
C60.0684 (2)0.0310 (6)0.82792 (13)0.0422 (7)
C70.1604 (2)0.2252 (7)0.86697 (13)0.0425 (7)
C80.2103 (2)0.5429 (6)0.97010 (13)0.0407 (7)
C90.4014 (2)0.8203 (6)0.97749 (12)0.0386 (7)
C100.4932 (2)0.8417 (7)0.94239 (13)0.0478 (8)
H100.48870.73330.90290.057*
C110.4091 (2)0.9828 (7)1.03623 (13)0.0472 (8)
H110.34900.97341.06100.057*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0557 (5)0.0955 (8)0.0554 (5)0.0286 (5)0.0299 (4)0.0292 (5)
O10.0538 (13)0.0916 (19)0.0525 (12)0.0245 (12)0.0274 (10)0.0201 (12)
N10.0372 (12)0.0525 (16)0.0409 (12)0.0114 (11)0.0155 (10)0.0048 (11)
N20.0427 (13)0.0514 (15)0.0378 (12)0.0114 (11)0.0136 (10)0.0052 (10)
C10.068 (2)0.081 (3)0.0476 (18)0.0252 (19)0.0218 (15)0.0127 (17)
C20.104 (3)0.103 (3)0.0458 (19)0.041 (3)0.0214 (19)0.025 (2)
C30.071 (2)0.074 (3)0.064 (2)0.024 (2)0.0035 (18)0.0142 (19)
C40.0462 (18)0.060 (2)0.064 (2)0.0110 (15)0.0133 (15)0.0022 (17)
C50.0475 (16)0.0525 (19)0.0415 (14)0.0021 (14)0.0131 (12)0.0058 (13)
C60.0457 (16)0.0428 (17)0.0390 (14)0.0002 (13)0.0103 (12)0.0013 (13)
C70.0452 (16)0.0465 (18)0.0373 (15)0.0027 (13)0.0120 (12)0.0019 (12)
C80.0399 (15)0.0432 (17)0.0401 (14)0.0026 (13)0.0103 (11)0.0044 (12)
C90.0399 (15)0.0430 (17)0.0333 (13)0.0032 (12)0.0078 (11)0.0037 (12)
C100.0487 (17)0.058 (2)0.0397 (15)0.0101 (14)0.0149 (13)0.0109 (14)
C110.0425 (16)0.060 (2)0.0433 (15)0.0087 (14)0.0188 (12)0.0040 (14)
Geometric parameters (Å, º) top
S1—C81.656 (3)C3—C41.373 (5)
O1—C71.227 (3)C3—H30.9300
N1—C71.374 (3)C4—C51.380 (4)
N1—C81.403 (3)C4—H40.9300
N1—H1A0.8600C5—C61.386 (4)
N2—C81.330 (3)C5—H50.9300
N2—C91.415 (3)C6—C71.481 (4)
N2—H2A0.8600C9—C111.385 (4)
C1—C21.376 (5)C9—C101.385 (4)
C1—C61.386 (4)C10—C11i1.376 (4)
C1—H10.9300C10—H100.9300
C2—C31.381 (5)C11—C10i1.376 (4)
C2—H20.9300C11—H110.9300
C7—N1—C8128.9 (2)C6—C5—H5119.7
C7—N1—H1A115.5C5—C6—C1118.6 (3)
C8—N1—H1A115.5C5—C6—C7125.0 (2)
C8—N2—C9132.6 (2)C1—C6—C7116.5 (3)
C8—N2—H2A113.7O1—C7—N1120.9 (3)
C9—N2—H2A113.7O1—C7—C6120.8 (2)
C2—C1—C6120.8 (3)N1—C7—C6118.3 (2)
C2—C1—H1119.6N2—C8—N1113.9 (2)
C6—C1—H1119.6N2—C8—S1127.6 (2)
C1—C2—C3120.1 (3)N1—C8—S1118.45 (19)
C1—C2—H2120.0C11—C9—C10118.2 (2)
C3—C2—H2120.0C11—C9—N2126.0 (2)
C4—C3—C2119.7 (3)C10—C9—N2115.8 (2)
C4—C3—H3120.1C11i—C10—C9122.5 (3)
C2—C3—H3120.1C11i—C10—H10118.8
C3—C4—C5120.2 (3)C9—C10—H10118.8
C3—C4—H4119.9C10i—C11—C9119.3 (2)
C5—C4—H4119.9C10i—C11—H11120.4
C4—C5—C6120.6 (3)C9—C11—H11120.4
C4—C5—H5119.7
C6—C1—C2—C30.4 (7)C5—C6—C7—N111.9 (4)
C1—C2—C3—C41.2 (7)C1—C6—C7—N1168.0 (3)
C2—C3—C4—C51.2 (6)C9—N2—C8—N1178.7 (3)
C3—C4—C5—C60.4 (5)C9—N2—C8—S10.3 (5)
C4—C5—C6—C11.9 (5)C7—N1—C8—N20.7 (4)
C4—C5—C6—C7177.9 (3)C7—N1—C8—S1178.4 (2)
C2—C1—C6—C52.0 (5)C8—N2—C9—C113.8 (5)
C2—C1—C6—C7177.9 (3)C8—N2—C9—C10175.8 (3)
C8—N1—C7—O13.9 (5)C11—C9—C10—C11i0.0 (5)
C8—N1—C7—C6176.1 (3)N2—C9—C10—C11i179.6 (3)
C5—C6—C7—O1168.1 (3)C10—C9—C11—C10i0.0 (5)
C1—C6—C7—O112.0 (5)N2—C9—C11—C10i179.6 (3)
Symmetry code: (i) x+1, y+2, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O10.861.852.590 (3)144
C11—H11···S10.932.563.215 (3)128
C5—H5···S1ii0.932.843.567 (3)136
Symmetry code: (ii) x, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC22H18N4O2S2
Mr434.52
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)11.513 (4), 4.5279 (16), 20.209 (7)
β (°) 101.146 (7)
V3)1033.6 (6)
Z2
Radiation typeMo Kα
µ (mm1)0.29
Crystal size (mm)0.50 × 0.15 × 0.13
Data collection
DiffractometerBruker SMART APEX CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.950, 0.964
No. of measured, independent and
observed [I > 2σ(I)] reflections
6173, 2142, 1529
Rint0.040
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.063, 0.171, 1.14
No. of reflections2142
No. of parameters136
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.23

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O10.861.852.590 (3)144
C11—H11···S10.932.563.215 (3)128
C5—H5···S1i0.932.843.567 (3)136
Symmetry code: (i) x, y+1, z+2.
 

Acknowledgements

The authors thank Universiti Kebangsaan Malaysia for providing facilities and the Ministry of Higher Education, Malaysia for research funding (grant Nos. UKM-ST-01- FRGS-0016–2006, UKM-GUP-BTT-07–30-190 and UKM-OUP-TK-16–73/2009).

References

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First citationArslan, H., Flörke, U. & Külcü, N. (2004). Acta Chim. Slov. 51, 787–792.  CAS Google Scholar
First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
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