(3aR,6R)-3,3,6-Trimethyl-3,3a,4,5,6,7-hexa­hydro-2H-indazole-2-carbo­thio­amide

N'Ait Ousidi, A.; Ait Itto, M.Y.; Auhmani, A.; Riahi, A.; Chevreux, S.; Berraho, M.

doi:10.1107/S2414314616005733

organic compounds

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ISSN: 2414-3146

Volume 1| Part 4| April 2016| x160573

doi:10.1107/S2414314616005733

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(3aR,6R)-3,3,6-Trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide

Abdellah N'Ait Ousidi,^a My Youssef Ait Itto,^a Aziz Auhmani,^a Abdelkhalek Riahi,^a Sylviane Chevreux ^b and Moha Berraho ^c ^*

^aLaboratoire de Synthèse Organique et Physico-Chimie Moléculaire, Département de Chimie, Faculté, des Sciences, Semlalia BP 2390, Marrakech 40001, Morocco, ^bInstitut de Chimie Moléculaire de Reims, CNRS UMR 7312 Bât. Europol'Agro, Moulin de la Housse UFR Sciences, BP 1039–51687 Reims Cédex 2, France, and ^cLaboratoire de Chimie des Substances Naturelles, "Unité Associé au CNRST (URAC16)", Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco
^*Correspondence e-mail: berraho@uca.ac.ma

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 16 March 2016; accepted 6 April 2016; online 12 April 2016)

The title compound, C₁₁H₁₉N₃S, was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The molecule is built up from fused six and five-membered rings. The six-membered ring adopts a chair conformation, while the five-membered ring displays an envelope conformation with the dimethyl-substituted C atom as the flap. The dihedral angle between the mean planes of the two rings is 20.35 (6)°. In the crystal, molecules are linked by N—H⋯N and N—H⋯S hydrogen bonds into chains running parallel to [100].

Keywords: crystal structure; indazole; carbothioamide; thiosemicarbazide; N—H⋯N hydrogen bonds; N—H⋯S hydrogen bonds.

CCDC reference: 1472696

3D view (loading...)

Chemical scheme

Structure description

In recent years, the synthesis of heterocyclic systems containing nitrogen has attracted great interest because of their broad spectrum of pharmacological activities. In particular, indazole is a crucial heterocyclic skeleton present in a wide variety of drugs, many natural products and biologically active compounds (Gautam et al., 2015 ). Compounds containing the indazole skeleton are known to display a broad spectrum of potent pharmacological activities including anti-inflammatory (Rosati et al., 2007 ), anti-depressant (Bailey et al., 1985 ), anticancer (De Lena et al., 2001 ), antituberculosis (Guo et al., 2010 ) and antimicrobial activities (Ali et al., 2012 ). The therapeutic usefulness of these heterocyclic systems prompted us to prepare a new substituted 2H-indazole from a naturally occurring monoterpene. The title compound (3aR,6R)-3,3,6-trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The resulting product obtained as diastereomeric mixture, was then crystallized from ethanol to give the new compound as white monocrystals.

The title molecule, Fig. 1, contains a fused ring system and a carbothioamide group as a substituent to the pyrazolidine ring. The six-membered ring (C1/C7/C8/C19—C12) has a chair conformation as indicated by puckering parameters Q_T = 0.5218 (16) Å, θ = 16.11 (18) and φ2 = 199.40 (16)°. The pyrazolidine ring (N1/N2/C1/C7/C14) adopts an envelope conformation with atom C14 as the flap; deviating by 0.341 (1) Å from the mean plane through the other four atoms in the ring.

Figure 1
Molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level. Labels very small

In the crystal, molecules are linked by N—H⋯N and N—H⋯S hydrogen bonds into chains running parallel to [100] (Table 1 and Fig. 2).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3B⋯N1ⁱ	0.86	2.37	3.230 (3)	176
N3—H3A⋯S1ⁱⁱ	0.86	2.70	3.442 (3)	146
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ ; (ii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ .

Figure 2
Partial crystal packing view along the c axis of the title compound. The N—H⋯N and N—H⋯S hydrogen bonds (dashed lines; Table 1

) indicate the formation of a chain parallel to the a axis. H atoms not involved in hydrogen bonding have been omitted for clarity.

Owing to the presence of the S atom, the absolute configuration could be fully confirmed, by refining the Flack parameter (Parsons et al., 2013 ), as C3a(R) and C6(R).

Synthesis and crystallization

A hot ethanolic solution containing equimolar quantities of thiosemicarbazide and (R)-pulegone with a few drops of concentrated HCl was heated under reflux. The progress of the reaction was monitored by TLC. After the completion of the reaction, the solvent was evaporated under reduced pressure and the crude product was purified by chromatography on silica gel (230–400 mesh) using hexane/ethyl acetate (95:5) as eluent. The pure indazolic product was obtained in 64% yield as a diastereomeric mixture. Slow evaporation from an ethanolic solution of the title compound gave crystals of the title compound, suitable for X-ray crystallographic analysis.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₁H₁₉N₃S
M_r	225.35
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	7.957 (5), 10.796 (5), 13.673 (5)
V (Å³)	1174.6 (10)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	2.21
Crystal size (mm)	0.24 × 0.2 × 0.15

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.618, 0.718
No. of measured, independent and observed [I > 2σ(I)] reflections	17550, 2315, 2270
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.054, 1.06
No. of reflections	2315
No. of parameters	140
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.17
Absolute structure	Parsons et al. (2013), 972 Friedel pairs
Absolute structure parameter	0.028 (12)
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), PLATON (Spek, 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1472696

Crystal structure: contains datablocks I, global. DOI: 10.1107/S2414314616005733/su4023sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616005733/su4023Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616005733/su4023Isup3.cml

checkCIF report

Experimental top

Structure description top

In recent years, the synthesis of heterocyclic systems containing nitrogen has attracted great interest because of their broad spectrum of pharmacological activities. In particular, indazole is a crucial heterocyclic skeleton present in a wide variety of drugs, many natural products and biologically active compounds (Gautam et al., 2015). Compounds containing the indazole skeleton are known to display a broad spectrum of potent pharmacological activities including anti-inflammatory (Rosati et al., 2007), anti-depressant (Bailey et al., 1985), anticancer (De Lena et al., 2001), antituberculosis (Guo et al., 2010) and antimicrobial activities (Ali et al., 2012). The therapeutic usefulness of these heterocyclic systems prompted us to prepare a new substituted 2H-indazole from a naturally occurring monoterpene. The title compound (3aR,6R)-3,3,6-trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide was prepared by the reaction of (R)-pulegone with thiosemicarbazide in acidic medium, using ethanol as solvent. The resulting product obtained as diastereomeric mixture, was then crystallized from ethanol to give the new compound as white monocrystals. The structure of this new product was confirmed by its single-crystal X-ray structure.

In the crystal, molecules are linked by N—H···N and N—H···S hydrogen bonds into chains running parallel to [100] (Table 1 and Fig. 2).

Owing to the presence of the S atom, the absolute configuration could be fully confirmed, by refining the Flack parameter (Parsons et al., 2013), as C3a(R) and C6(R).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. Molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Partial crystal packing view along the c axis of the title compound. The N—H···N and N—H···S hydrogen bonds (dashed lines; Table 1) indicate the formation of a chain parallel to the a axis. H atoms not involved in hydrogen bonding have been omitted for clarity.

(3aR,6R)-3,3,6-Trimethyl-3,3a,4,5,6,7-hexahydro-2H-indazole-2-carbothioamide top

Crystal data top

C₁₁H₁₉N₃S	D_x = 1.274 Mg m⁻³
M_r = 225.35	Cu Kα radiation, λ = 1.5418 Å
Orthorhombic, P2₁2₁2₁	Cell parameters from 17550 reflections
a = 7.957 (5) Å	θ = 5.2–72.9°
b = 10.796 (5) Å	µ = 2.21 mm⁻¹
c = 13.673 (5) Å	T = 100 K
V = 1174.6 (10) Å³	Prismatic, colourless
Z = 4	0.24 × 0.2 × 0.15 mm
F(000) = 488

Data collection top

Bruker APEXII CCD diffractometer	2315 independent reflections
Radiation source: microsource	2270 reflections with I > 2σ(I)
Multi-layer mirror monochromator	R_int = 0.027
φ and ω scans	θ_max = 72.2°, θ_min = 5.2°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −9→9
T_min = 0.618, T_max = 0.718	k = −12→13
17550 measured reflections	l = −16→16

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.021	H-atom parameters constrained
wR(F²) = 0.054	w = 1/[σ²(F_o²) + (0.0309P)² + 0.2126P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
2315 reflections	Δρ_max = 0.22 e Å⁻³
140 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Absolute structure: Parsons et al. (2013), 972 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.028 (12)

Crystal data top

C₁₁H₁₉N₃S	V = 1174.6 (10) Å³
M_r = 225.35	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 7.957 (5) Å	µ = 2.21 mm⁻¹
b = 10.796 (5) Å	T = 100 K
c = 13.673 (5) Å	0.24 × 0.2 × 0.15 mm

Data collection top

Bruker APEXII CCD diffractometer	2315 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2270 reflections with I > 2σ(I)
T_min = 0.618, T_max = 0.718	R_int = 0.027
17550 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	H-atom parameters constrained
wR(F²) = 0.054	Δρ_max = 0.22 e Å⁻³
S = 1.06	Δρ_min = −0.17 e Å⁻³
2315 reflections	Absolute structure: Parsons et al. (2013), 972 Friedel pairs
140 parameters	Absolute structure parameter: 0.028 (12)
0 restraints

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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	0.15695 (3)	0.04077 (2)	0.529496 (19)	0.01460 (8)
C1	0.68856 (13)	0.02162 (11)	0.35481 (8)	0.0111 (2)
N2	0.45543 (12)	0.03660 (9)	0.43699 (7)	0.01126 (18)
N1	0.59405 (12)	0.10135 (9)	0.39659 (7)	0.01179 (19)
C4	0.33782 (15)	0.10291 (10)	0.48530 (7)	0.0117 (2)
N3	0.37036 (13)	0.22324 (9)	0.49959 (7)	0.0167 (2)
H3A	0.4626	0.2548	0.4784	0.020*
H3B	0.2990	0.2690	0.5300	0.020*
C6	0.31991 (15)	−0.10083 (12)	0.31667 (9)	0.0171 (2)
H6A	0.2100	−0.0815	0.3413	0.026*
H6B	0.3194	−0.1827	0.2893	0.026*
H6C	0.3503	−0.0421	0.2670	0.026*
C7	0.63141 (14)	−0.10999 (10)	0.36496 (8)	0.0117 (2)
H7	0.6947	−0.1462	0.4194	0.014*
C8	0.66596 (16)	−0.19039 (10)	0.27468 (9)	0.0168 (2)
H8A	0.5851	−0.1713	0.2238	0.020*
H8B	0.6542	−0.2772	0.2916	0.020*
C9	0.40770 (15)	−0.18861 (10)	0.48000 (9)	0.0167 (2)
H9A	0.4661	−0.1662	0.5388	0.025*
H9B	0.4432	−0.2695	0.4593	0.025*
H9C	0.2889	−0.1894	0.4922	0.025*
C10	0.87482 (14)	−0.02785 (11)	0.21395 (8)	0.0148 (2)
H10	0.9909	−0.0184	0.1912	0.018*
C11	0.85262 (14)	0.05119 (10)	0.30711 (8)	0.0137 (2)
H11A	0.9439	0.0344	0.3523	0.016*
H11B	0.8561	0.1384	0.2902	0.016*
C12	0.84475 (17)	−0.16553 (11)	0.23718 (9)	0.0176 (2)
H12A	0.8640	−0.2141	0.1786	0.021*
H12B	0.9250	−0.1922	0.2862	0.021*
C13	0.75792 (16)	0.01904 (12)	0.13366 (9)	0.0191 (3)
H13A	0.7674	−0.0336	0.0773	0.029*
H13B	0.7887	0.1021	0.1162	0.029*
H13C	0.6441	0.0181	0.1569	0.029*
C14	0.44718 (14)	−0.09470 (10)	0.40007 (8)	0.0116 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.01105 (13)	0.01600 (13)	0.01675 (13)	−0.00067 (11)	0.00364 (10)	−0.00051 (11)
C1	0.0114 (5)	0.0133 (5)	0.0086 (5)	0.0002 (4)	−0.0023 (4)	0.0002 (4)
N2	0.0104 (4)	0.0093 (4)	0.0141 (4)	−0.0019 (4)	0.0017 (3)	0.0004 (4)
N1	0.0098 (4)	0.0138 (4)	0.0118 (4)	−0.0025 (4)	0.0008 (3)	0.0007 (4)
C4	0.0118 (5)	0.0136 (5)	0.0098 (5)	0.0015 (4)	−0.0011 (4)	0.0013 (4)
N3	0.0140 (5)	0.0134 (5)	0.0228 (5)	0.0001 (4)	0.0053 (4)	−0.0047 (4)
C6	0.0134 (6)	0.0202 (6)	0.0178 (5)	0.0002 (5)	−0.0018 (5)	−0.0035 (5)
C7	0.0105 (5)	0.0121 (5)	0.0125 (5)	0.0008 (4)	0.0001 (4)	0.0012 (4)
C8	0.0183 (6)	0.0123 (5)	0.0197 (5)	0.0000 (5)	0.0035 (5)	−0.0034 (4)
C9	0.0172 (5)	0.0128 (5)	0.0200 (6)	−0.0022 (4)	0.0020 (5)	0.0034 (5)
C10	0.0108 (5)	0.0195 (6)	0.0141 (5)	0.0014 (5)	0.0029 (4)	−0.0009 (5)
C11	0.0100 (5)	0.0164 (5)	0.0148 (5)	−0.0015 (5)	0.0007 (4)	−0.0004 (4)
C12	0.0163 (6)	0.0175 (5)	0.0189 (5)	0.0045 (5)	0.0032 (5)	−0.0029 (4)
C13	0.0182 (6)	0.0260 (7)	0.0131 (5)	0.0003 (5)	0.0011 (4)	0.0014 (5)
C14	0.0120 (5)	0.0093 (5)	0.0134 (5)	0.0002 (4)	0.0002 (4)	−0.0010 (4)

Geometric parameters (Å, º) top

S1—C4	1.6990 (14)	C8—H8A	0.9700
C1—N1	1.2778 (16)	C8—H8B	0.9700
C1—C11	1.4938 (16)	C9—C14	1.5235 (16)
C1—C7	1.4983 (16)	C9—H9A	0.9600
N2—C4	1.3507 (15)	C9—H9B	0.9600
N2—N1	1.4180 (14)	C9—H9C	0.9600
N2—C14	1.5062 (15)	C10—C13	1.5254 (16)
C4—N3	1.3390 (15)	C10—C12	1.5387 (18)
N3—H3A	0.8600	C10—C11	1.5433 (15)
N3—H3B	0.8600	C10—H10	0.9800
C6—C14	1.5265 (17)	C11—H11A	0.9700
C6—H6A	0.9600	C11—H11B	0.9700
C6—H6B	0.9600	C12—H12A	0.9700
C6—H6C	0.9600	C12—H12B	0.9700
C7—C8	1.5339 (15)	C13—H13A	0.9600
C7—C14	1.5513 (17)	C13—H13B	0.9600
C7—H7	0.9800	C13—H13C	0.9600
C8—C12	1.5358 (19)

N1—C1—C11	124.44 (11)	C14—C9—H9C	109.5
N1—C1—C7	114.76 (10)	H9A—C9—H9C	109.5
C11—C1—C7	120.55 (10)	H9B—C9—H9C	109.5
C4—N2—N1	117.92 (10)	C13—C10—C12	111.98 (10)
C4—N2—C14	129.24 (9)	C13—C10—C11	109.92 (10)
N1—N2—C14	111.55 (8)	C12—C10—C11	110.24 (9)
C1—N1—N2	107.45 (10)	C13—C10—H10	108.2
N3—C4—N2	116.85 (10)	C12—C10—H10	108.2
N3—C4—S1	119.67 (9)	C11—C10—H10	108.2
N2—C4—S1	123.47 (9)	C1—C11—C10	110.02 (9)
C4—N3—H3A	120.0	C1—C11—H11A	109.7
C4—N3—H3B	120.0	C10—C11—H11A	109.7
H3A—N3—H3B	120.0	C1—C11—H11B	109.7
C14—C6—H6A	109.5	C10—C11—H11B	109.7
C14—C6—H6B	109.5	H11A—C11—H11B	108.2
H6A—C6—H6B	109.5	C8—C12—C10	112.45 (10)
C14—C6—H6C	109.5	C8—C12—H12A	109.1
H6A—C6—H6C	109.5	C10—C12—H12A	109.1
H6B—C6—H6C	109.5	C8—C12—H12B	109.1
C1—C7—C8	114.07 (9)	C10—C12—H12B	109.1
C1—C7—C14	102.39 (9)	H12A—C12—H12B	107.8
C8—C7—C14	118.59 (10)	C10—C13—H13A	109.5
C1—C7—H7	107.0	C10—C13—H13B	109.5
C8—C7—H7	107.0	H13A—C13—H13B	109.5
C14—C7—H7	107.0	C10—C13—H13C	109.5
C7—C8—C12	109.62 (10)	H13A—C13—H13C	109.5
C7—C8—H8A	109.7	H13B—C13—H13C	109.5
C12—C8—H8A	109.7	N2—C14—C9	113.26 (9)
C7—C8—H8B	109.7	N2—C14—C6	108.67 (9)
C12—C8—H8B	109.7	C9—C14—C6	111.73 (10)
H8A—C8—H8B	108.2	N2—C14—C7	99.36 (8)
C14—C9—H9A	109.5	C9—C14—C7	110.25 (9)
C14—C9—H9B	109.5	C6—C14—C7	113.02 (10)
H9A—C9—H9B	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···N1ⁱ	0.86	2.37	3.230 (3)	176
N3—H3A···S1ⁱⁱ	0.86	2.70	3.442 (3)	146

Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3B···N1ⁱ	0.86	2.37	3.230 (3)	176
N3—H3A···S1ⁱⁱ	0.86	2.70	3.442 (3)	146

Symmetry codes: (i) x−1/2, −y+1/2, −z+1; (ii) x+1/2, −y+1/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₁H₁₉N₃S
M_r	225.35
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	7.957 (5), 10.796 (5), 13.673 (5)
V (Å³)	1174.6 (10)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	2.21
Crystal size (mm)	0.24 × 0.2 × 0.15

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.618, 0.718
No. of measured, independent and observed [I > 2σ(I)] reflections	17550, 2315, 2270
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.618

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.054, 1.06
No. of reflections	2315
No. of parameters	140
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.17
Absolute structure	Parsons et al. (2013), 972 Friedel pairs
Absolute structure parameter	0.028 (12)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Acknowledgements

The authors thank Pr. Auhmani Abdelouhed as laboratory manager.

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