2-(Adamantan-1-yl)-5-(4-nitro­phen­yl)-1,3,4-oxadiazole

El-Emam, A.A.; Kadi, A.A.; El-Brollosy, N.R.; Ng, S.W.; Tiekink, E.R.T.

doi:10.1107/S1600536812005302

organic compounds

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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Page o795

doi:10.1107/S1600536812005302

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2-(Adamantan-1-yl)-5-(4-nitrophenyl)-1,3,4-oxadiazole

Ali A. El-Emam,^a ‡ Adnan A. Kadi,^a Nasser R. El-Brollosy,^a Seik Weng Ng ^b,^c and Edward R. T. Tiekink ^b ^*

^aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and ^cChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
^*Correspondence e-mail: edward.tiekink@gmail.com

(Received 4 February 2012; accepted 6 February 2012; online 24 February 2012)

The title molecule, C₁₈H₁₉N₃O₃, lies on a mirror plane that bisects the adamantyl group. In the crystal, C—H⋯O and C—H⋯N interactions lead to supramolecular chains along [100]. These assemble into layers in the ab plane via π–π interactions [centroid–centroid distance = 3.6548 (7) Å] between the oxadiazole and benzene rings.

Related literature

For the biological activity of adamantyl-1,3,4-oxadiazole derivatives, see: Kadi et al. (2007 ); El-Emam et al. (2004 ). For related adamantane structures, see: Al-Tamimi et al. (2010 ); Kadi et al. (2011 ).

Experimental

Crystal data

C₁₈H₁₉N₃O₃
M_r = 325.36
Monoclinic, P 2₁ /m
a = 6.8502 (6) Å
b = 6.5705 (7) Å
c = 17.6761 (15) Å
β = 98.432 (8)°
V = 786.99 (13) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 100 K
0.30 × 0.30 × 0.15 mm

Data collection

Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ) T_min = 0.972, T_max = 0.986
3236 measured reflections
1956 independent reflections
1456 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.123
S = 1.05
1956 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13A⋯N2ⁱ	0.95	2.59	3.297 (3)	132
C16—H16A⋯O2ⁱⁱ	0.95	2.49	3.256 (3)	137
Symmetry codes: (i) x+1, y, z; (ii) x-1, y, z.

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and DIAMOND (Brandenburg, 2006 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812005302/gg2074sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812005302/gg2074Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812005302/gg2074Isup3.cml

checkCIF report

Comment top

Adamantane derivatives have been reported to exhibit marked anti-bacterial and anti-inflammatory activities (Kadi et al., 2007; El-Emam et al., 2004). In continuation of our interest in the chemical and pharmacological properties of adamantane derivatives, and as part of on-going structural studies of adamantane derivatives (Kadi et al., 2011; Al-Tamimi et al., 2010), the title compound, (I), was prepared as a potential chemotherapeutic agent.

The molecule of (I), Fig. 1, lies on a mirror plane that bisects the adamantyl residue. The molecules are linked into a supramolecular linear chains along [100] via C—H···O and C—H···N interactions, Fig. 2 and Table 1. The aforementioned interactions lead to 10-membered {···HC₂NO···HC₃N} synthons. The chains are linked into layers in the ab plane by π–π interactions occurring between the oxadiazole and phenyl rings [centroid···centroid distance = 3.6548 (7) Å, angle between rings = 0° for symmetry operation 2 - x, -1/2 + y, 1 - z]. Layers stack along the b axis with no specific interactions between them.

Related literature top

For the biological activity of adamantyl-1,3,4-oxadiazole derivatives, see: Kadi et al. (2007); El-Emam et al. (2004). For related adamantane structures, see: Al-Tamimi et al. (2010); Kadi et al. (2011).

Experimental top

The title compound was prepared following our previously described method (Kadi et al., 2007). A mixture of 4-nitrobenzoic acid hydrazide (1.81 g, 0.01 mol), 1-adamantane carboxylic acid (1.8 g, 0.01 mol) and phosphorus oxychloride (8 ml) was heated under reflux for 1 h. On cooling, crushed ice (50 g) was added and the mixture was stirred for 30 min. The separated crude product was filtered, washed with water, then with saturated sodium hydrogen carbonate solution and finally with water, dried and crystallized from EtOH/CHCl₃ to yield 2.96 g (91%) of the title compound as colourless crystals. M.pt.: 511–513 K. ¹H NMR (CDCl₃): δ 1.79 (s, 6H, adamantane-H), 2.08 (s, 9H, adamantane-H), 7.61 (d, 2H, Ar—H, J = 8.3 Hz), 8.33 (d, 2H, Ar—H, J = 8.3 Hz). ¹³C NMR: δ 27.10, 33.15, 36.80, 39.82 (adamantane-C), 125.15, 128.20, 141.95, 145.10 (Ar—C), 163.25 (oxadiazole C-5), 173.05 (oxadiazole C-2).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.
	Fig. 2. A view of the linear supramolecular chain along [100] in (I). The C—H···O and C—H···N interactions are shown as orange and blue dashed lines, respectively.
	Fig. 3. A view of a supramolecular layer in (I) whereby the chains illustrated in Fig. 2 are linked by π–π interactions (purple dashed lines).
	Fig. 4. A view in projection along the b axis of the unit-cell contents for (I), highlighting the stacking of layers.

2-(Adamantan-1-yl)-5-(4-nitrophenyl)-1,3,4-oxadiazole top

Crystal data top

C₁₈H₁₉N₃O₃	F(000) = 344
M_r = 325.36	D_x = 1.373 Mg m⁻³
Monoclinic, P2₁/m	Melting point: 512 K
Hall symbol: -P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 6.8502 (6) Å	Cell parameters from 1102 reflections
b = 6.5705 (7) Å	θ = 3.0–27.5°
c = 17.6761 (15) Å	µ = 0.10 mm⁻¹
β = 98.432 (8)°	T = 100 K
V = 786.99 (13) Å³	Prism, colourless
Z = 2	0.30 × 0.30 × 0.15 mm

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	1956 independent reflections
Radiation source: SuperNova (Mo) X-ray Source	1456 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.027
Detector resolution: 10.4041 pixels mm^-1	θ_max = 27.6°, θ_min = 3.0°
ω scan	h = −8→6
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −8→5
T_min = 0.972, T_max = 0.986	l = −23→20
3236 measured reflections

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0476P)² + 0.27P] where P = (F_o² + 2F_c²)/3
1956 reflections	(Δ/σ)_max = 0.001
136 parameters	Δρ_max = 0.30 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₁₈H₁₉N₃O₃	V = 786.99 (13) Å³
M_r = 325.36	Z = 2
Monoclinic, P2₁/m	Mo Kα radiation
a = 6.8502 (6) Å	µ = 0.10 mm⁻¹
b = 6.5705 (7) Å	T = 100 K
c = 17.6761 (15) Å	0.30 × 0.30 × 0.15 mm
β = 98.432 (8)°

Data collection top

Agilent SuperNova Dual diffractometer with an Atlas detector	1956 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	1456 reflections with I > 2σ(I)
T_min = 0.972, T_max = 0.986	R_int = 0.027
3236 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.123	H-atom parameters constrained
S = 1.05	Δρ_max = 0.30 e Å⁻³
1956 reflections	Δρ_min = −0.34 e Å⁻³
136 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
O1	0.9944 (2)	0.2500	0.34929 (8)	0.0164 (3)
O2	1.7026 (2)	0.2500	0.67325 (10)	0.0406 (6)
O3	1.4757 (2)	0.2500	0.74600 (9)	0.0243 (4)
N1	0.6690 (3)	0.2500	0.33989 (10)	0.0178 (4)
N2	0.7505 (3)	0.2500	0.41856 (10)	0.0171 (4)
N3	1.5294 (3)	0.2500	0.68283 (11)	0.0216 (4)
C1	0.8170 (3)	0.2500	0.30226 (12)	0.0156 (4)
C2	0.8215 (3)	0.2500	0.21783 (12)	0.0148 (4)
C3	0.9314 (2)	0.4411 (2)	0.19610 (9)	0.0195 (4)
H3A	0.8624	0.5649	0.2101	0.023*
H3B	1.0672	0.4426	0.2245	0.023*
C4	0.9390 (2)	0.4400 (2)	0.10939 (9)	0.0204 (4)
H4A	1.0100	0.5642	0.0953	0.024*
C5	1.0483 (3)	0.2500	0.08863 (13)	0.0227 (5)
H5A	1.0563	0.2500	0.0332	0.027*
H5B	1.1844	0.2500	0.1168	0.027*
C6	0.6100 (3)	0.2500	0.17372 (12)	0.0184 (5)
H6A	0.5382	0.1279	0.1875	0.022*	0.50
H6B	0.5382	0.3721	0.1875	0.022*	0.50
C7	0.6192 (3)	0.2500	0.08724 (12)	0.0198 (5)
H7	0.4821	0.2500	0.0586	0.024*
C8	0.7279 (2)	0.0604 (3)	0.06587 (9)	0.0214 (4)
H8A	0.7318	0.0591	0.0101	0.026*
H8B	0.6572	−0.0632	0.0790	0.026*
C10	0.9399 (3)	0.2500	0.42055 (12)	0.0148 (4)
C11	1.0933 (3)	0.2500	0.48726 (12)	0.0148 (4)
C12	1.2920 (3)	0.2500	0.47852 (12)	0.0184 (5)
H12A	1.3293	0.2500	0.4288	0.022*
C13	1.4351 (3)	0.2500	0.54269 (13)	0.0206 (5)
H13A	1.5712	0.2500	0.5375	0.025*
C14	1.3771 (3)	0.2500	0.61451 (12)	0.0166 (5)
C15	1.1807 (3)	0.2500	0.62466 (12)	0.0163 (5)
H15A	1.1445	0.2500	0.6745	0.020*
C16	1.0384 (3)	0.2500	0.56058 (12)	0.0163 (5)
H16A	0.9026	0.2500	0.5663	0.020*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0157 (8)	0.0229 (8)	0.0104 (7)	0.000	0.0019 (6)	0.000
O2	0.0151 (9)	0.0839 (17)	0.0224 (9)	0.000	0.0019 (7)	0.000
O3	0.0265 (9)	0.0349 (10)	0.0117 (8)	0.000	0.0031 (7)	0.000
N1	0.0194 (9)	0.0220 (10)	0.0123 (9)	0.000	0.0030 (7)	0.000
N2	0.0190 (10)	0.0210 (10)	0.0115 (9)	0.000	0.0024 (7)	0.000
N3	0.0197 (10)	0.0301 (11)	0.0149 (9)	0.000	0.0025 (8)	0.000
C1	0.0162 (10)	0.0159 (10)	0.0143 (10)	0.000	0.0011 (8)	0.000
C2	0.0153 (10)	0.0186 (11)	0.0107 (9)	0.000	0.0027 (8)	0.000
C3	0.0245 (8)	0.0199 (8)	0.0142 (7)	−0.0043 (7)	0.0036 (6)	−0.0010 (6)
C4	0.0259 (8)	0.0210 (8)	0.0147 (7)	−0.0066 (7)	0.0048 (6)	0.0019 (6)
C5	0.0178 (11)	0.0383 (14)	0.0128 (10)	0.000	0.0049 (9)	0.000
C6	0.0165 (11)	0.0256 (12)	0.0131 (10)	0.000	0.0024 (9)	0.000
C7	0.0180 (11)	0.0273 (12)	0.0138 (10)	0.000	0.0008 (9)	0.000
C8	0.0291 (9)	0.0222 (8)	0.0129 (7)	−0.0049 (7)	0.0030 (7)	−0.0030 (6)
C10	0.0188 (11)	0.0149 (10)	0.0116 (10)	0.000	0.0049 (8)	0.000
C11	0.0164 (11)	0.0152 (10)	0.0127 (10)	0.000	0.0023 (8)	0.000
C12	0.0191 (11)	0.0243 (12)	0.0126 (10)	0.000	0.0049 (9)	0.000
C13	0.0152 (11)	0.0296 (13)	0.0173 (11)	0.000	0.0033 (9)	0.000
C14	0.0174 (11)	0.0185 (11)	0.0133 (10)	0.000	0.0002 (8)	0.000
C15	0.0201 (11)	0.0172 (11)	0.0125 (10)	0.000	0.0051 (8)	0.000
C16	0.0162 (11)	0.0189 (11)	0.0145 (10)	0.000	0.0042 (8)	0.000

Geometric parameters (Å, º) top

O1—C10	1.365 (2)	C7—C8ⁱ	1.527 (2)
O1—C1	1.368 (3)	C7—C8	1.527 (2)
O2—N3	1.223 (2)	C7—H7	1.0000
O3—N3	1.226 (2)	C8—C4ⁱ	1.535 (2)
C1—N1	1.292 (3)	C8—H8A	0.9900
C1—C2	1.497 (3)	C8—H8B	0.9900
C2—C3ⁱ	1.5412 (19)	C10—N2	1.293 (3)
C2—C3	1.5412 (19)	C10—C11	1.460 (3)
C2—C6	1.542 (3)	C11—C12	1.392 (3)
C3—C4	1.541 (2)	C11—C16	1.402 (3)
C3—H3A	0.9900	C12—C13	1.386 (3)
C3—H3B	0.9900	C12—H12A	0.9500
C4—C5	1.528 (2)	C13—C14	1.385 (3)
C4—C8ⁱ	1.535 (2)	C13—H13A	0.9500
C4—H4A	1.0000	C14—C15	1.383 (3)
C5—C4ⁱ	1.528 (2)	C14—N3	1.475 (3)
C5—H5A	0.9900	C15—C16	1.382 (3)
C5—H5B	0.9900	C15—H15A	0.9500
C6—C7	1.539 (3)	C16—H16A	0.9500
C6—H6A	0.9900	N1—N2	1.421 (2)
C6—H6B	0.9900

C10—O1—C1	102.83 (16)	C8—C7—C6	109.77 (12)
N1—C1—O1	112.43 (18)	C8ⁱ—C7—H7	109.3
N1—C1—C2	130.2 (2)	C8—C7—H7	109.3
O1—C1—C2	117.35 (17)	C6—C7—H7	109.3
C1—C2—C3ⁱ	109.31 (12)	C7—C8—C4ⁱ	109.56 (14)
C1—C2—C3	109.31 (12)	C7—C8—H8A	109.8
C3ⁱ—C2—C3	109.10 (17)	C4ⁱ—C8—H8A	109.8
C1—C2—C6	110.42 (17)	C7—C8—H8B	109.8
C3ⁱ—C2—C6	109.34 (12)	C4ⁱ—C8—H8B	109.8
C3—C2—C6	109.34 (12)	H8A—C8—H8B	108.2
C4—C3—C2	109.45 (13)	N2—C10—O1	112.58 (18)
C4—C3—H3A	109.8	N2—C10—C11	128.51 (19)
C2—C3—H3A	109.8	O1—C10—C11	118.91 (18)
C4—C3—H3B	109.8	C12—C11—C16	120.1 (2)
C2—C3—H3B	109.8	C12—C11—C10	120.67 (18)
H3A—C3—H3B	108.2	C16—C11—C10	119.19 (19)
C5—C4—C8ⁱ	109.71 (14)	C13—C12—C11	119.7 (2)
C5—C4—C3	109.36 (14)	C13—C12—H12A	120.2
C8ⁱ—C4—C3	109.38 (13)	C11—C12—H12A	120.2
C5—C4—H4A	109.5	C12—C13—C14	119.1 (2)
C8ⁱ—C4—H4A	109.5	C12—C13—H13A	120.4
C3—C4—H4A	109.5	C14—C13—H13A	120.4
C4ⁱ—C5—C4	109.59 (17)	C15—C14—C13	122.3 (2)
C4ⁱ—C5—H5A	109.8	C15—C14—N3	118.57 (19)
C4—C5—H5A	109.8	C13—C14—N3	119.13 (19)
C4ⁱ—C5—H5B	109.8	C16—C15—C14	118.46 (19)
C4—C5—H5B	109.8	C16—C15—H15A	120.8
H5A—C5—H5B	108.2	C14—C15—H15A	120.8
C7—C6—C2	109.26 (17)	C15—C16—C11	120.3 (2)
C7—C6—H6A	109.8	C15—C16—H16A	119.8
C2—C6—H6A	109.8	C11—C16—H16A	119.8
C7—C6—H6B	109.8	C1—N1—N2	106.17 (18)
C2—C6—H6B	109.8	C10—N2—N1	105.99 (17)
H6A—C6—H6B	108.3	O2—N3—O3	123.5 (2)
C8ⁱ—C7—C8	109.38 (18)	O2—N3—C14	118.08 (18)
C8ⁱ—C7—C6	109.77 (12)	O3—N3—C14	118.39 (18)

C10—O1—C1—N1	0	N2—C10—C11—C12	180
C10—O1—C1—C2	180	O1—C10—C11—C12	0
N1—C1—C2—C3ⁱ	−120.32 (12)	N2—C10—C11—C16	0
O1—C1—C2—C3ⁱ	59.68 (12)	O1—C10—C11—C16	180
N1—C1—C2—C3	120.32 (12)	C16—C11—C12—C13	0
O1—C1—C2—C3	−59.68 (12)	C10—C11—C12—C13	180
N1—C1—C2—C6	0	C11—C12—C13—C14	0
O1—C1—C2—C6	180	C12—C13—C14—C15	0
C1—C2—C3—C4	179.20 (14)	C12—C13—C14—N3	180
C3ⁱ—C2—C3—C4	59.7 (2)	C13—C14—C15—C16	0
C6—C2—C3—C4	−59.83 (17)	N3—C14—C15—C16	180
C2—C3—C4—C5	−60.23 (18)	C14—C15—C16—C11	0
C2—C3—C4—C8ⁱ	59.94 (17)	C12—C11—C16—C15	0
C8ⁱ—C4—C5—C4ⁱ	−59.3 (2)	C10—C11—C16—C15	180
C3—C4—C5—C4ⁱ	60.7 (2)	O1—C1—N1—N2	0
C1—C2—C6—C7	180	C2—C1—N1—N2	180
C3ⁱ—C2—C6—C7	−59.70 (11)	O1—C10—N2—N1	0
C3—C2—C6—C7	59.70 (11)	C11—C10—N2—N1	180
C2—C6—C7—C8ⁱ	−60.13 (12)	C1—N1—N2—C10	0
C2—C6—C7—C8	60.13 (12)	C15—C14—N3—O2	180
C8ⁱ—C7—C8—C4ⁱ	60.1 (2)	C13—C14—N3—O2	0
C6—C7—C8—C4ⁱ	−60.40 (18)	C15—C14—N3—O3	0
C1—O1—C10—N2	0	C13—C14—N3—O3	180
C1—O1—C10—C11	180

Symmetry code: (i) x, −y+1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···N2ⁱⁱ	0.95	2.59	3.297 (3)	132
C16—H16A···O2ⁱⁱⁱ	0.95	2.49	3.256 (3)	137

Symmetry codes: (ii) x+1, y, z; (iii) x−1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₉N₃O₃
M_r	325.36
Crystal system, space group	Monoclinic, P2₁/m
Temperature (K)	100
a, b, c (Å)	6.8502 (6), 6.5705 (7), 17.6761 (15)
β (°)	98.432 (8)
V (Å³)	786.99 (13)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.30 × 0.30 × 0.15

Data collection
Diffractometer	Agilent SuperNova Dual diffractometer with an Atlas detector
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2011)
T_min, T_max	0.972, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections	3236, 1956, 1456
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.123, 1.05
No. of reflections	1956
No. of parameters	136
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.34

Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···N2ⁱ	0.95	2.59	3.297 (3)	132
C16—H16A···O2ⁱⁱ	0.95	2.49	3.256 (3)	137

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

Footnotes

‡Additional correspondence author, e-mail: elemam5@hotmail.com.

Acknowledgements

The financial support of the Deanship of Scientific Research and the Research Center of the College of Pharmacy, King Saud University, is greatly appreciated. We also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR/MOHE/SC/12).

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