Prasugrel, a new medicine for preventing blockages in the arteries

Wang, Z.-M.; Zhao, J.; Xu, G.

doi:10.1107/S1600536810017095

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 6| June 2010| Page o1354

https://doi.org/10.1107/S1600536810017095

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Prasugrel, a new medicine for preventing blockages in the arteries

Zhi-Mei Wang,^a ^* Jian Zhao ^a and Gang Xu ^a

^aSchool of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, People's Republic of China
^*Correspondence e-mail: zhimeiwang@yahoo.cn

(Received 11 March 2010; accepted 10 May 2010; online 15 May 2010)

Prasugrel {systematic name: 5-[(2-cyclopropylcarbonyl)(2-fluorophenyl)methyl]-4,5,6,7-tetrahydrothieno[3,2-c]pyridin-2-yl acetate}, C₂₀H₂₀FNO₃S, is a new third-generation thienopyridine which was recently approved for clinical use as a more potent blocker of the platelet P2Y₁₂ receptor than clopidogrel, which was previously used for this purpose. The molecule features a tetrahydrothienopyridine system with the tetrahydropyridine ring showing a half-chair conformation; the dihedral angle formed by the the planes of the benzene and thiophene rings is 83.17 (3)°.

Related literature

For the biological activity of the title compound, see: Farid et al. (2008 ). For details of the synthesis, see: Sun et al. (2009 ).

Experimental

Crystal data

C₂₀H₂₀FNO₃S
M_r = 373.43
Triclinic, $[P \overline 1]$
a = 7.910 (2) Å
b = 9.943 (3) Å
c = 12.450 (4) Å
α = 112.938 (5)°
β = 90.644 (5)°
γ = 92.591 (6)°
V = 900.3 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.21 mm⁻¹
T = 291 K
0.32 × 0.28 × 0.26 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2000 ) T_min = 0.936, T_max = 0.947
5345 measured reflections
3201 independent reflections
2379 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.106
wR(F²) = 0.198
S = 1.08
3201 reflections
235 parameters
H-atom parameters constrained
Δρ_max = 0.73 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810017095/ya2121sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810017095/ya2121Isup2.hkl

checkCIF report

Comment top

Prasugrel was recently approved for clinical use in combination with aspirin as an option for preventing blockages in the arteries in patients with acute coronary syndromes who are undergoing treatment via percutaneous coronary intervention (Farid et al., 2008). Both enantiomers of prasugrel show similar activity, therefore it was approved for use in its racemic form. The synthesis of prasugrel has been published recently (Sun et al., 2009). Herein we report its crystal structure (Fig. 1).

The tetrahydropyridine ring of the bicyclic thienopyridine system shows a half-chair conformation with the N1 and C8 atoms displaced by -0.408 (7) Å and 0.411 (7) Å from the plane of C5, C6, C7 and C9 atoms, which are coplanar within 0.003 Å. The dihedral angle formed by the the planes of the benzene and thiophene rings (C11-C16 and C3, C4, C5, C6, S1, respectively) is equal to 83.17 (3)°.

Related literature top

For the biological activity of the title compound, see: Farid et al. (2008). For details of the synthesis, see: Sun et al. (2009).

Experimental top

The description of the seven-step synthesis of the title compound is published by Sun et al. (2009). Here we report the details for the two final steps of the synthesis.

Synthesis of 5-(2-cyclopropyl-1-(2-fluorophenyl)-2-oxoethyl) -5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one. Under N₂ atmosphere, 5,6,7,7a-tetrahydrothieno[3,2-c] pyridin-2(4H)-one hydrochloride (19.1 g, 0.1 mol) and N,N-diisopropylformamide (27.1 g, 0.21 mol) were dissolved in 60 ml of CH₃CN. 2-Bromo-1-cyclopropyl-2-(2-fluorophenyl)ethanone (28.1 g, 0.11 mol) was added to the solution at 40°C. The mixture was stirred for 8 h and poured into H₂O (500 ml), then extracted with ethyl acetate (50 ml x 3). The organic phase was collected and washed with saturated NaCl solution (80 ml x 4), then dried with anhydrous Na₂SO₄ and filtered. The filtrate was distilled in vacuo and the solvent was removed. The residue was separated with column chromatography and pale-yellow oil of 5-(2-cyclopropyl-1-(2-fluorophenyl)-2-oxoethyl)-5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one was obtained (12 g. 41%).

Synthesis of prasugrel. 5-(2-Cyclopropyl-1-(2-fluorophenyl)-2-oxoethyl)-5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one (3.31 g, 0.01 mol) was dissolved in the mixture of DMF (20 ml) and acetate anhydride (1.13 ml, 0.012 mol). NaH (0.44 g, 0.011 mol) was added at 0°C and stirred for 1 h at room temperature. The reaction solution was poured into iced water (50 ml) and extracted with ethyl acetate (30 ml x 3). The organic phase was separated and washed with saturated NaCl solution (50 ml x 4), then dried with anhydrous Na₂SO₄ and filtered. The filtrate was distilled in vacuo and the solvent was removed. The residue was washed in 10 ml of ether, and thus prasugrel, in the form of colorless solid, was obtained (2.5 g, 66%).

0.074 g (2 mmol) of prasugrel powder were dissolved in 20 ml of methanol and then slowly evaporated. After two weeks, colorless block crystals were obtained and collected [yield 83.8% (0.062 g)].

Structure description top

For the biological activity of the title compound, see: Farid et al. (2008). For details of the synthesis, see: Sun et al. (2009).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound with thermal ellipsoids drawn at the 30% probability level.

5-[(2-cyclopropylcarbonyl)(2-fluorophenyl)methyl]-4,5,6,7- tetrahydrothieno[3,2-c]pyridin-2-yl acetate top

Crystal data top

C₂₀H₂₀FNO₃S	Z = 2
M_r = 373.43	F(000) = 392
Triclinic, P1	D_x = 1.378 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.910 (2) Å	Cell parameters from 1069 reflections
b = 9.943 (3) Å	θ = 2.2–21.9°
c = 12.450 (4) Å	µ = 0.21 mm⁻¹
α = 112.938 (5)°	T = 291 K
β = 90.644 (5)°	Block, colorless
γ = 92.591 (6)°	0.32 × 0.28 × 0.26 mm
V = 900.3 (5) Å³

Data collection top

Bruker SMART CCD diffractometer	3201 independent reflections
Radiation source: fine-focus sealed tube	2379 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
φ and ω scans	θ_max = 25.2°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −9→9
T_min = 0.936, T_max = 0.947	k = −11→10
5345 measured reflections	l = −13→14

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.106	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.198	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0117P)² + 3.2142P] where P = (F_o² + 2F_c²)/3
3201 reflections	(Δ/σ)_max = 0.001
235 parameters	Δρ_max = 0.73 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₂₀H₂₀FNO₃S	γ = 92.591 (6)°
M_r = 373.43	V = 900.3 (5) Å³
Triclinic, P1	Z = 2
a = 7.910 (2) Å	Mo Kα radiation
b = 9.943 (3) Å	µ = 0.21 mm⁻¹
c = 12.450 (4) Å	T = 291 K
α = 112.938 (5)°	0.32 × 0.28 × 0.26 mm
β = 90.644 (5)°

Data collection top

Bruker SMART CCD diffractometer	3201 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	2379 reflections with I > 2σ(I)
T_min = 0.936, T_max = 0.947	R_int = 0.027
5345 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.106	0 restraints
wR(F²) = 0.198	H-atom parameters constrained
S = 1.08	Δρ_max = 0.73 e Å⁻³
3201 reflections	Δρ_min = −0.26 e Å⁻³
235 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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

	x	y	z	U_iso*/U_eq
S1	0.98277 (19)	0.7094 (2)	0.12388 (13)	0.0633 (5)
F1	0.8924 (5)	0.9710 (5)	−0.3950 (4)	0.0885 (12)
C1	1.4971 (8)	0.5727 (9)	0.2034 (6)	0.080 (2)
H1A	1.5091	0.5806	0.2825	0.120*
H1B	1.5907	0.6251	0.1861	0.120*
H1C	1.4953	0.4716	0.1514	0.120*
C2	1.3386 (8)	0.6352 (8)	0.1886 (5)	0.074 (2)
C3	1.1688 (7)	0.6812 (7)	0.0487 (5)	0.0526 (15)
C4	1.1564 (7)	0.7042 (6)	−0.0503 (5)	0.0533 (15)
H4A	1.2443	0.6929	−0.1016	0.064*
C5	0.9935 (7)	0.7477 (6)	−0.0677 (4)	0.0482 (13)
C6	0.8868 (7)	0.7542 (7)	0.0175 (4)	0.0528 (15)
C7	0.7093 (7)	0.8012 (8)	0.0226 (5)	0.0643 (18)
H7A	0.6854	0.8667	0.1014	0.077*
H7B	0.6301	0.7167	−0.0004	0.077*
C8	0.6913 (7)	0.8786 (7)	−0.0600 (5)	0.0625 (17)
H8A	0.5732	0.8971	−0.0675	0.075*
H8B	0.7554	0.9719	−0.0289	0.075*
C9	0.9400 (7)	0.7866 (7)	−0.1670 (5)	0.0538 (15)
H9A	0.9894	0.8825	−0.1555	0.065*
H9B	0.9814	0.7164	−0.2392	0.065*
C10	0.7071 (7)	0.8485 (6)	−0.2608 (5)	0.0491 (14)
H10A	0.7532	0.9498	−0.2343	0.059*
C11	0.7730 (6)	0.7596 (6)	−0.3819 (4)	0.0437 (13)
C12	0.8627 (7)	0.8249 (6)	−0.4420 (5)	0.0475 (13)
C13	0.9202 (7)	0.7512 (7)	−0.5530 (5)	0.0574 (16)
H13A	0.9813	0.8007	−0.5910	0.069*
C14	0.8856 (8)	0.6067 (8)	−0.6044 (5)	0.0620 (16)
H14A	0.9245	0.5550	−0.6787	0.074*
C15	0.7937 (9)	0.5342 (8)	−0.5491 (6)	0.0714 (19)
H15A	0.7685	0.4341	−0.5863	0.086*
C16	0.7382 (9)	0.6108 (7)	−0.4370 (5)	0.0679 (18)
H16A	0.6771	0.5613	−0.3990	0.082*
C17	0.5147 (7)	0.8444 (7)	−0.2809 (5)	0.0517 (14)
C18	0.4630 (8)	0.9356 (7)	−0.3427 (5)	0.0654 (17)
H18A	0.5474	1.0094	−0.3454	0.079*
C19	0.2829 (9)	0.9711 (9)	−0.3429 (6)	0.089 (2)
H19A	0.2054	0.9357	−0.2987	0.106*
H19B	0.2590	1.0659	−0.3429	0.106*
C20	0.3480 (9)	0.8650 (9)	−0.4476 (6)	0.085 (2)
H20A	0.3651	0.8935	−0.5130	0.102*
H20B	0.3115	0.7632	−0.4688	0.102*
N1	0.7541 (5)	0.7875 (5)	−0.1760 (4)	0.0494 (12)
O1	1.2404 (8)	0.6812 (10)	0.2594 (4)	0.168 (4)
O2	1.3121 (5)	0.6278 (5)	0.0798 (3)	0.0711 (13)
O3	0.4151 (5)	0.7686 (5)	−0.2536 (4)	0.0692 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0504 (9)	0.1083 (14)	0.0387 (8)	0.0199 (9)	0.0111 (6)	0.0349 (8)
F1	0.092 (3)	0.092 (3)	0.090 (3)	0.005 (2)	0.024 (2)	0.043 (3)
C1	0.070 (4)	0.121 (6)	0.063 (4)	0.032 (4)	0.006 (3)	0.047 (4)
C2	0.064 (4)	0.112 (6)	0.045 (4)	0.027 (4)	0.005 (3)	0.027 (4)
C3	0.045 (3)	0.078 (4)	0.039 (3)	0.014 (3)	0.009 (2)	0.027 (3)
C4	0.047 (3)	0.075 (4)	0.044 (3)	0.016 (3)	0.014 (3)	0.027 (3)
C5	0.046 (3)	0.061 (4)	0.039 (3)	0.009 (3)	0.004 (2)	0.021 (3)
C6	0.047 (3)	0.076 (4)	0.034 (3)	0.009 (3)	0.002 (2)	0.019 (3)
C7	0.047 (3)	0.106 (5)	0.040 (3)	0.022 (3)	0.008 (3)	0.027 (3)
C8	0.053 (4)	0.085 (5)	0.040 (3)	0.024 (3)	0.002 (3)	0.012 (3)
C9	0.048 (3)	0.077 (4)	0.042 (3)	0.014 (3)	0.009 (3)	0.028 (3)
C10	0.048 (3)	0.057 (4)	0.044 (3)	0.003 (3)	0.001 (2)	0.022 (3)
C11	0.038 (3)	0.058 (4)	0.041 (3)	0.004 (2)	−0.001 (2)	0.026 (3)
C12	0.048 (3)	0.045 (3)	0.055 (3)	0.004 (3)	−0.003 (3)	0.026 (3)
C13	0.054 (4)	0.080 (5)	0.053 (4)	0.012 (3)	0.012 (3)	0.042 (4)
C14	0.066 (4)	0.075 (5)	0.047 (3)	0.014 (3)	0.007 (3)	0.024 (3)
C15	0.087 (5)	0.065 (4)	0.057 (4)	−0.001 (4)	0.004 (4)	0.018 (3)
C16	0.084 (5)	0.074 (5)	0.047 (4)	0.005 (4)	0.007 (3)	0.024 (3)
C17	0.048 (3)	0.069 (4)	0.038 (3)	0.005 (3)	0.003 (3)	0.021 (3)
C18	0.052 (4)	0.086 (5)	0.068 (4)	0.005 (3)	−0.002 (3)	0.041 (4)
C19	0.066 (5)	0.135 (7)	0.072 (5)	0.027 (5)	−0.006 (4)	0.047 (5)
C20	0.100 (6)	0.108 (6)	0.057 (4)	0.007 (5)	−0.014 (4)	0.043 (4)
N1	0.045 (3)	0.069 (3)	0.037 (2)	0.015 (2)	0.005 (2)	0.022 (2)
O1	0.121 (5)	0.333 (10)	0.051 (3)	0.131 (6)	0.019 (3)	0.063 (5)
O2	0.060 (3)	0.117 (4)	0.050 (2)	0.039 (3)	0.012 (2)	0.044 (3)
O3	0.049 (2)	0.111 (4)	0.061 (3)	−0.007 (2)	−0.005 (2)	0.051 (3)

Geometric parameters (Å, º) top

S1—C3	1.727 (5)	C10—N1	1.460 (7)
S1—C6	1.731 (5)	C10—C11	1.531 (7)
F1—C12	1.346 (6)	C10—C17	1.535 (7)
C1—C2	1.464 (8)	C10—H10A	0.9800
C1—H1A	0.9600	C11—C12	1.355 (7)
C1—H1B	0.9600	C11—C16	1.380 (8)
C1—H1C	0.9600	C12—C13	1.381 (8)
C2—O1	1.150 (7)	C13—C14	1.338 (8)
C2—O2	1.342 (7)	C13—H13A	0.9300
C3—C4	1.342 (7)	C14—C15	1.368 (9)
C3—O2	1.385 (6)	C14—H14A	0.9300
C4—C5	1.418 (7)	C15—C16	1.392 (8)
C4—H4A	0.9300	C15—H15A	0.9300
C5—C6	1.346 (7)	C16—H16A	0.9300
C5—C9	1.494 (7)	C17—O3	1.206 (7)
C6—C7	1.494 (7)	C17—C18	1.467 (8)
C7—C8	1.515 (8)	C18—C19	1.483 (8)
C7—H7A	0.9700	C18—C20	1.492 (9)
C7—H7B	0.9700	C18—H18A	0.9800
C8—N1	1.480 (6)	C19—C20	1.438 (9)
C8—H8A	0.9700	C19—H19A	0.9700
C8—H8B	0.9700	C19—H19B	0.9700
C9—N1	1.474 (6)	C20—H20A	0.9700
C9—H9A	0.9700	C20—H20B	0.9700
C9—H9B	0.9700

C3—S1—C6	90.2 (3)	C17—C10—H10A	109.4
C2—C1—H1A	109.5	C12—C11—C16	116.7 (5)
C2—C1—H1B	109.5	C12—C11—C10	121.3 (5)
H1A—C1—H1B	109.5	C16—C11—C10	121.9 (5)
C2—C1—H1C	109.5	F1—C12—C11	119.3 (5)
H1A—C1—H1C	109.5	F1—C12—C13	116.8 (5)
H1B—C1—H1C	109.5	C11—C12—C13	123.9 (6)
O1—C2—O2	121.5 (6)	C14—C13—C12	118.3 (6)
O1—C2—C1	125.3 (6)	C14—C13—H13A	120.9
O2—C2—C1	113.1 (5)	C12—C13—H13A	120.9
C4—C3—O2	122.4 (5)	C13—C14—C15	120.9 (6)
C4—C3—S1	112.7 (4)	C13—C14—H14A	119.6
O2—C3—S1	124.6 (4)	C15—C14—H14A	119.6
C3—C4—C5	112.1 (5)	C14—C15—C16	119.7 (7)
C3—C4—H4A	123.9	C14—C15—H15A	120.1
C5—C4—H4A	123.9	C16—C15—H15A	120.1
C6—C5—C4	113.0 (5)	C11—C16—C15	120.5 (6)
C6—C5—C9	121.4 (5)	C11—C16—H16A	119.7
C4—C5—C9	125.6 (5)	C15—C16—H16A	119.7
C5—C6—C7	124.1 (5)	O3—C17—C18	122.7 (5)
C5—C6—S1	112.0 (4)	O3—C17—C10	123.7 (5)
C7—C6—S1	123.9 (4)	C18—C17—C10	113.6 (5)
C6—C7—C8	108.0 (5)	C17—C18—C19	119.3 (6)
C6—C7—H7A	110.1	C17—C18—C20	117.3 (6)
C8—C7—H7A	110.1	C19—C18—C20	57.8 (4)
C6—C7—H7B	110.1	C17—C18—H18A	116.5
C8—C7—H7B	110.1	C19—C18—H18A	116.5
H7A—C7—H7B	108.4	C20—C18—H18A	116.5
N1—C8—C7	110.0 (5)	C20—C19—C18	61.4 (5)
N1—C8—H8A	109.7	C20—C19—H19A	117.6
C7—C8—H8A	109.7	C18—C19—H19A	117.6
N1—C8—H8B	109.7	C20—C19—H19B	117.6
C7—C8—H8B	109.7	C18—C19—H19B	117.6
H8A—C8—H8B	108.2	H19A—C19—H19B	114.7
N1—C9—C5	111.1 (4)	C19—C20—C18	60.8 (4)
N1—C9—H9A	109.4	C19—C20—H20A	117.7
C5—C9—H9A	109.4	C18—C20—H20A	117.7
N1—C9—H9B	109.4	C19—C20—H20B	117.7
C5—C9—H9B	109.4	C18—C20—H20B	117.7
H9A—C9—H9B	108.0	H20A—C20—H20B	114.8
N1—C10—C11	111.6 (4)	C10—N1—C9	109.7 (4)
N1—C10—C17	112.8 (5)	C10—N1—C8	109.8 (4)
C11—C10—C17	104.1 (4)	C9—N1—C8	108.6 (4)
N1—C10—H10A	109.4	C2—O2—C3	121.6 (4)
C11—C10—H10A	109.4

Experimental details

Crystal data
Chemical formula	C₂₀H₂₀FNO₃S
M_r	373.43
Crystal system, space group	Triclinic, P1
Temperature (K)	291
a, b, c (Å)	7.910 (2), 9.943 (3), 12.450 (4)
α, β, γ (°)	112.938 (5), 90.644 (5), 92.591 (6)
V (Å³)	900.3 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.21
Crystal size (mm)	0.32 × 0.28 × 0.26

Data collection
Diffractometer	Bruker SMART CCD
Absorption correction	Multi-scan (SADABS; Sheldrick, 2000)
T_min, T_max	0.936, 0.947
No. of measured, independent and observed [I > 2σ(I)] reflections	5345, 3201, 2379
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.106, 0.198, 1.08
No. of reflections	3201
No. of parameters	235
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.73, −0.26

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXTL (Sheldrick, 2008).

Acknowledgements

The authors thank the Program for Young Excellent Talents in Southeast University for financial support.

References

Bruker (2000). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
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Sheldrick, G. M. (2000). SADABS. University of Göttingen, Germany. Google Scholar
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