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

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ISSN: 2056-9890

(+)-(S,S)-1,3-Bis[(tetra­hydro­furan-2-yl)­meth­yl]thio­urea

aLaboratorio de Síntesis de Complejos, Facultad de Ciencias Químicas, Universidad Autónoma de Puebla, AP 1067, 72001 Puebla, Pue., Mexico, and bDEP Facultad de Ciencias Químicas, UANL, Guerrero y Progreso S/N, Col. Treviño, 64570 Monterrey, NL, Mexico
*Correspondence e-mail: sylvain_bernes@Hotmail.com

(Received 19 November 2008; accepted 1 December 2008; online 13 December 2008)

The title compound, C11H20N2O2S, is an enanti­omerically pure heterocycle-substituted thio­urea synthesized under solvent-free conditions. The thio­urea unit adopts a ZZ conformation, with the HN—(C=S)—NH core almost planar and the tetra­hydro­furfuryl groups placed below and above this plane. The whole mol­ecule thus approximates to noncrystallographic C2 symmetry. Unexpectedly, the C=S group is not involved in inter­molecular hydrogen bonding, as generally observed in homodisubstituted thioureas. Instead, mol­ecules form a one-dimensional network based on weak N—H⋯O(heterocycle) hydrogen bonding, resulting in a zigzag ribbon-like structure around the crystallographic 21 screw axis along [100].

Related literature

For general background about solvent-free synthesis, see: Tanaka & Toda (2000[Tanaka, K. & Toda, F. (2000). Chem. Rev. 100, 1025-1074.]); Jeon et al. (2005[Jeon, S.-J., Li, H. & Walsh, P. J. (2005). J. Am. Chem. Soc. 127, 16416-16425.]). For C2 homosubstituted thio­ureas, see: Bailey et al. (1997[Bailey, P. J., Grant, K. J. & Parsons, S. (1997). Acta Cryst. C53, 247-248.]); Lai & Tiekink (2002[Lai, C. S. & Tiekink, E. R. T. (2002). Acta Cryst. E58, o538-o539.]). For common hydrogen-bonding schemes in thio­ureas, see: Vázquez et al. (2004[Vázquez, J., Bernès, S., Reyes, Y., Moya, M., Sharma, P., Álvarez, C. & Gutiérrez, R. (2004). Synthesis, pp. 1955-1958.]); Custelcean et al. (2005[Custelcean, R., Gorbunova, M. G. & Bonnesen, P. V. (2005). Chem. Eur. J. 11, 1459-1466.]); Shashidhar et al. (2006[Shashidhar, Thiruvenkatam, V., Shivashankar, S. A., Halli, M. B. & Guru Row, T. N. (2006). Acta Cryst. E62, o1518-o1519.]); Sadiq-ur-Rehman et al. (2007[Sadiq-ur-Rehman, Ali, S. & Parvez, M. (2007). Acta Cryst. E63, o640-o641.]); Saxena & Pike (2007[Saxena, A. & Pike, R. D. (2007). J. Chem. Crystallogr. 37, 755-764.]).

[Scheme 1]

Experimental

Crystal data
  • C11H20N2O2S

  • Mr = 244.35

  • Orthorhombic, P 21 21 21

  • a = 7.8588 (9) Å

  • b = 10.8265 (11) Å

  • c = 15.6196 (16) Å

  • V = 1329.0 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 298 (1) K

  • 0.6 × 0.6 × 0.6 mm

Data collection
  • Siemens P4 diffractometer

  • Absorption correction: ψ scan (XSCANS; Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) Tmin = 0.782, Tmax = 0.870

  • 4611 measured reflections

  • 3026 independent reflections

  • 2484 reflections with I > 2σ(I)

  • Rint = 0.031

  • 3 standard reflections every 97 reflections intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.165

  • S = 1.03

  • 3026 reflections

  • 151 parameters

  • 2 restraints

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

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.16 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1267 Friedel pairs

  • Flack parameter: −0.01 (14)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯O18i 0.85 (1) 2.095 (17) 2.897 (3) 157 (3)
N12—H12⋯O8ii 0.86 (1) 2.197 (18) 2.978 (3) 150 (3)
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]; (ii) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1].

Data collection: XSCANS (Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: XSCANS; 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: Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The development of straightforward and eco-friendly synthetic procedures remains an important aim in organic synthesis. Many organic solvents, particularly chlorinated hydrocarbons, that are used in large quantities in organic reactions are potential threat to human health and environment. Thus, the design of chemical reactions under solvent-free conditions is getting a renewed interest. In this regard, solvent-free organic syntheses have great applied value and expansive prospects considering their advantages such as high efficiency and selectivity, easy separation and purification and environmental acceptability. All these merits are in accord with the green chemistry's requests of energy-saving, high efficiency and environmentally benign features (Tanaka & Toda, 2000; Jeon et al., 2005). On the other hand, N,N'-disubstituted thioureas have recently received much interest due to their diverse applications, such as, inter alia, antiviral, antituberculous, fungicidal, herbicidal activities, as well as tranquilizing and antidiabetic drugs, agrochemical properties, antioxidants in gasoline, corrosion inhibitors, etc. In view of these and in continuation of our earlier work on the synthesis of thioureas (Vázquez et al., 2004), we synthesized the title compound under solvent-free conditions (see experimental).

The asymmetric unit contains one molecule in general position (Fig. 1). As the amine used as starting material was enantiopure, the thiourea is found to be a pure (S,S) isomer. The central core HN—(CS)—NH unit is close to be planar, the r.m.s. deviation from the mean plane S1/C1/N2/H2/N12/H12 being 0.039 Å. This core adopts a ZZ conformation (i.e. amine H atoms are arranged syn) and tetrahydrofurfuryl groups are placed below and above the central HN—(CS)—NH plane. The whole molecule thus approximates a local C2 point symmetry. The observed conformation is identical to that found in other related homosubstituted thioureas (Lai & Tiekink, 2002; Bailey et al., 1997).

The ZZ conformation avoids the formation of intramolecular hydrogen bonds (Saxena & Pike, 2007). Regarding the packing structure, it is clear that the thioketone functionality does not participate in intermolecular contacts. Such a situation is unexpected, since for previously X-ray characterized chiral and non-chiral homosubstituted thioureas, one-dimensional supramolecular structures based on CS···H—N hydrogen bonds are predominant, providing that the thiourea is in a ZZ conformation (e.g. Vázquez et al., 2004; Custelcean et al., 2005; Shashidhar et al., 2006; Sadiq-ur-Rehman et al., 2007). Instead, the crystal structure of the title compound is determined by weak N—H···O(heterocycle) hydrogen bonds, aggregating molecules in a backbone arrangement (Fig. 2), parallel to the crystallographic 21 screw axis along [100].

Related literature top

For general background about solvent-free synthesis, see: Tanaka & Toda (2000); Jeon et al. (2005). For C2 homosubstituted thioureas, see: Bailey et al. (1997); Lai & Tiekink (2002). For common hydrogen-bonding schemes in thioureas, see: Vázquez et al. (2004); Custelcean et al. (2005); Shashidhar et al. (2006); Sadiq-ur-Rehman et al. (2007); Saxena & Pike (2007).

Experimental top

Under solvent-free conditions, (S)-(+)-tetrahydrofurfurylamine (0.49 g, 4.88 mmol) and CS2 (0.19 g, 2.44 mmol) were mixed at 298 K, giving a white solid. The crude was recrystallized from EtOH, affording colourless crystals of the title compound. Yield 99%; m.p. 376–378 K; [α]25D=+28.7 (c=1, CHCl3). Anal. Calcd for C11H20N2O2S: C 54.07, H 8.25, N 11.46, O 13.10, S 13.12%; found: C 53.12, H 8.18, N 11.30, O 12.98, S 13.87%. Spectroscopic data are in agreement with the X-ray formula (see archived CIF).

Refinement top

Methylene and methine H atoms were placed in idealized positions and refined as riding to their carrier C atoms. Amine H atoms, H2 and H12, were found in a difference map and refined with N—H bond lengths restrained to 0.86 (1) Å. For all H atoms, isotropic displacement parameters were calculated as Uiso(H) = 1.2Ueq(carrier atom).

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: XSCANS (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, with 30% probability level displacement ellipsoids for non-H atoms.
[Figure 2] Fig. 2. Part of the crystal structure of the title compound, showing the network of N—H···O hydrogen bonds (dashed lines). The 21 screw axis forming the backbone supramolecular structure is shown with a standard symbol, and each molecule has a color corresponding to symmetry related positions in the crystal: grey: asymmetric unit; red: -1/2 + x, 3/2 - y, 1 - z; green: 1/2 + x, 3/2 - y, 1 - z; blue: 1 + x, y, z; purple: 3/2 + x, 3/2 - y, 1 - z.
(+)-(S,S)-1,3-Bis[(tetrahydrofuran-2-yl)methyl]thiourea top
Crystal data top
C11H20N2O2SDx = 1.221 Mg m3
Mr = 244.35Melting point = 376–378 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 78 reflections
a = 7.8588 (9) Åθ = 4.6–13.7°
b = 10.8265 (11) ŵ = 0.23 mm1
c = 15.6196 (16) ÅT = 298 K
V = 1329.0 (2) Å3Block, colourless
Z = 40.6 × 0.6 × 0.6 mm
F(000) = 528
Data collection top
Siemens P4
diffractometer
2484 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 27.5°, θmin = 2.3°
2θ/ω scansh = 1010
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
k = 1414
Tmin = 0.782, Tmax = 0.870l = 2020
4611 measured reflections3 standard reflections every 97 reflections
3026 independent reflections intensity decay: 1%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.054H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.165 w = 1/[σ2(Fo2) + (0.0916P)2 + 0.2186P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
3026 reflectionsΔρmax = 0.22 e Å3
151 parametersΔρmin = 0.16 e Å3
2 restraintsAbsolute structure: Flack (1983), 1267 Friedel pairs
0 constraintsAbsolute structure parameter: 0.01 (14)
Primary atom site location: structure-invariant direct methods
Crystal data top
C11H20N2O2SV = 1329.0 (2) Å3
Mr = 244.35Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 7.8588 (9) ŵ = 0.23 mm1
b = 10.8265 (11) ÅT = 298 K
c = 15.6196 (16) Å0.6 × 0.6 × 0.6 mm
Data collection top
Siemens P4
diffractometer
2484 reflections with I > 2σ(I)
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
Rint = 0.031
Tmin = 0.782, Tmax = 0.8703 standard reflections every 97 reflections
4611 measured reflections intensity decay: 1%
3026 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.054H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.165Δρmax = 0.22 e Å3
S = 1.03Δρmin = 0.16 e Å3
3026 reflectionsAbsolute structure: Flack (1983), 1267 Friedel pairs
151 parametersAbsolute structure parameter: 0.01 (14)
2 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.48959 (12)0.46401 (7)0.34087 (6)0.0889 (3)
C10.4852 (3)0.5875 (2)0.40545 (16)0.0582 (5)
N20.4051 (3)0.6930 (2)0.38410 (17)0.0688 (6)
H20.389 (5)0.752 (2)0.4186 (18)0.083*
C30.3199 (4)0.7142 (4)0.3037 (2)0.0845 (9)
H3A0.37680.66680.25940.101*
H3B0.33030.80090.28890.101*
C40.1361 (4)0.6803 (3)0.30448 (19)0.0750 (8)
H4A0.12250.59520.32480.090*
C50.0534 (7)0.6947 (6)0.2172 (3)0.1303 (19)
H5A0.10880.75910.18420.156*
H5B0.05820.61800.18520.156*
C60.1224 (7)0.7283 (7)0.2368 (3)0.146 (2)
H6A0.16360.78980.19670.175*
H6B0.19570.65630.23360.175*
C70.1204 (6)0.7774 (6)0.3230 (3)0.1225 (16)
H7A0.14980.86440.32200.147*
H7B0.20330.73440.35800.147*
O80.0435 (3)0.7618 (2)0.35753 (14)0.0872 (7)
N120.5602 (3)0.5888 (2)0.48261 (15)0.0677 (5)
H120.541 (4)0.651 (2)0.5153 (17)0.081*
C130.6525 (4)0.4849 (3)0.5184 (2)0.0796 (8)
H13A0.59440.40920.50260.096*
H13B0.65030.49110.58030.096*
C140.8356 (3)0.4768 (2)0.48913 (18)0.0647 (6)
H14A0.83940.48200.42650.078*
C150.9260 (6)0.3588 (3)0.5178 (4)0.1075 (14)
H15A0.87230.32430.56840.129*
H15B0.92520.29720.47270.129*
C161.0986 (6)0.3991 (4)0.5365 (4)0.1293 (18)
H16A1.14210.35690.58670.155*
H16B1.17310.38150.48850.155*
C171.0897 (5)0.5297 (5)0.5515 (4)0.132 (2)
H17A1.10460.54650.61210.158*
H17B1.18010.57110.52050.158*
O180.9296 (3)0.57528 (19)0.52400 (18)0.0850 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0894 (5)0.0744 (4)0.1029 (6)0.0133 (4)0.0215 (5)0.0363 (4)
C10.0455 (10)0.0558 (11)0.0733 (14)0.0014 (10)0.0034 (11)0.0067 (10)
N20.0585 (12)0.0615 (12)0.0864 (15)0.0100 (10)0.0053 (11)0.0065 (11)
C30.0738 (18)0.098 (2)0.0813 (18)0.0236 (18)0.0124 (15)0.0169 (17)
C40.0749 (18)0.0776 (17)0.0724 (16)0.0170 (15)0.0110 (14)0.0098 (14)
C50.117 (3)0.194 (5)0.081 (2)0.061 (4)0.026 (2)0.034 (3)
C60.114 (4)0.217 (6)0.107 (3)0.064 (4)0.045 (3)0.035 (4)
C70.075 (2)0.160 (4)0.133 (4)0.036 (3)0.009 (2)0.030 (3)
O80.0645 (11)0.1192 (17)0.0778 (12)0.0116 (11)0.0004 (10)0.0262 (11)
N120.0551 (11)0.0755 (13)0.0725 (13)0.0009 (10)0.0071 (10)0.0105 (11)
C130.0672 (15)0.0860 (19)0.0856 (18)0.0126 (14)0.0081 (14)0.0201 (16)
C140.0654 (13)0.0590 (13)0.0698 (14)0.0061 (11)0.0113 (11)0.0025 (12)
C150.107 (3)0.0628 (16)0.153 (4)0.0133 (17)0.039 (3)0.004 (2)
C160.096 (3)0.104 (3)0.188 (5)0.032 (2)0.051 (3)0.006 (3)
C170.0660 (19)0.128 (4)0.201 (5)0.005 (2)0.030 (3)0.052 (4)
O180.0640 (11)0.0632 (10)0.1278 (18)0.0006 (9)0.0082 (12)0.0171 (11)
Geometric parameters (Å, º) top
S1—C11.675 (2)C7—H7B0.97
C1—N121.342 (3)N12—C131.450 (4)
C1—N21.346 (3)N12—H120.862 (10)
N2—C31.442 (4)C13—C141.513 (4)
N2—H20.849 (10)C13—H13A0.97
C3—C41.490 (5)C13—H13B0.97
C3—H3A0.97C14—O181.407 (3)
C3—H3B0.97C14—C151.529 (4)
C4—O81.413 (4)C14—H14A0.98
C4—C51.519 (5)C15—C161.454 (7)
C4—H4A0.98C15—H15A0.97
C5—C61.461 (7)C15—H15B0.97
C5—H5A0.97C16—C171.436 (6)
C5—H5B0.97C16—H16A0.97
C6—C71.447 (6)C16—H16B0.97
C6—H6A0.97C17—O181.418 (5)
C6—H6B0.97C17—H17A0.97
C7—O81.407 (5)C17—H17B0.97
C7—H7A0.97
N12—C1—N2114.8 (2)C7—O8—C4108.8 (3)
N12—C1—S1122.69 (19)C1—N12—C13123.9 (2)
N2—C1—S1122.5 (2)C1—N12—H12118 (2)
C1—N2—C3124.6 (3)C13—N12—H12118 (2)
C1—N2—H2124 (2)N12—C13—C14113.8 (2)
C3—N2—H2111 (3)N12—C13—H13A108.8
N2—C3—C4113.8 (3)C14—C13—H13A108.8
N2—C3—H3A108.8N12—C13—H13B108.8
C4—C3—H3A108.8C14—C13—H13B108.8
N2—C3—H3B108.8H13A—C13—H13B107.7
C4—C3—H3B108.8O18—C14—C13109.8 (2)
H3A—C3—H3B107.7O18—C14—C15106.0 (2)
O8—C4—C3110.5 (3)C13—C14—C15113.7 (3)
O8—C4—C5104.0 (3)O18—C14—H14A109.1
C3—C4—C5112.5 (4)C13—C14—H14A109.1
O8—C4—H4A109.9C15—C14—H14A109.1
C3—C4—H4A109.9C16—C15—C14104.0 (3)
C5—C4—H4A109.9C16—C15—H15A111.0
C6—C5—C4104.0 (4)C14—C15—H15A111.0
C6—C5—H5A111.0C16—C15—H15B111.0
C4—C5—H5A111.0C14—C15—H15B111.0
C6—C5—H5B111.0H15A—C15—H15B109.0
C4—C5—H5B111.0C17—C16—C15106.4 (4)
H5A—C5—H5B109.0C17—C16—H16A110.4
C7—C6—C5106.0 (4)C15—C16—H16A110.4
C7—C6—H6A110.5C17—C16—H16B110.4
C5—C6—H6A110.5C15—C16—H16B110.4
C7—C6—H6B110.5H16A—C16—H16B108.6
C5—C6—H6B110.5O18—C17—C16109.7 (4)
H6A—C6—H6B108.7O18—C17—H17A109.7
O8—C7—C6108.8 (3)C16—C17—H17A109.7
O8—C7—H7A109.9O18—C17—H17B109.7
C6—C7—H7A109.9C16—C17—H17B109.7
O8—C7—H7B109.9H17A—C17—H17B108.2
C6—C7—H7B109.9C14—O18—C17108.6 (3)
H7A—C7—H7B108.3
N12—C1—N2—C3178.2 (3)N2—C1—N12—C13179.6 (2)
S1—C1—N2—C32.2 (4)S1—C1—N12—C130.0 (4)
C1—N2—C3—C491.0 (4)C1—N12—C13—C1484.0 (3)
N2—C3—C4—O868.5 (4)N12—C13—C14—O1868.7 (3)
N2—C3—C4—C5175.7 (3)N12—C13—C14—C15172.8 (3)
O8—C4—C5—C628.9 (6)O18—C14—C15—C1622.6 (5)
C3—C4—C5—C6148.5 (5)C13—C14—C15—C16143.3 (4)
C4—C5—C6—C721.4 (7)C14—C15—C16—C1721.4 (7)
C5—C6—C7—O86.3 (7)C15—C16—C17—O1813.3 (8)
C6—C7—O8—C412.9 (6)C13—C14—O18—C17138.2 (4)
C3—C4—O8—C7146.8 (4)C15—C14—O18—C1715.0 (5)
C5—C4—O8—C725.9 (5)C16—C17—O18—C141.6 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O18i0.85 (1)2.10 (2)2.897 (3)157 (3)
N12—H12···O8ii0.86 (1)2.20 (2)2.978 (3)150 (3)
Symmetry codes: (i) x1/2, y+3/2, z+1; (ii) x+1/2, y+3/2, z+1.

Experimental details

Crystal data
Chemical formulaC11H20N2O2S
Mr244.35
Crystal system, space groupOrthorhombic, P212121
Temperature (K)298
a, b, c (Å)7.8588 (9), 10.8265 (11), 15.6196 (16)
V3)1329.0 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.6 × 0.6 × 0.6
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correctionψ scan
(XSCANS; Siemens, 1996)
Tmin, Tmax0.782, 0.870
No. of measured, independent and
observed [I > 2σ(I)] reflections
4611, 3026, 2484
Rint0.031
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.165, 1.03
No. of reflections3026
No. of parameters151
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.22, 0.16
Absolute structureFlack (1983), 1267 Friedel pairs
Absolute structure parameter0.01 (14)

Computer programs: XSCANS (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O18i0.85 (1)2.095 (17)2.897 (3)157 (3)
N12—H12···O8ii0.86 (1)2.197 (18)2.978 (3)150 (3)
Symmetry codes: (i) x1/2, y+3/2, z+1; (ii) x+1/2, y+3/2, z+1.
 

Acknowledgements

Partial support from VIEP-UAP (grant No. GUPJ-NAT08-G) is acknowledged.

References

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