Crystal structure of 4,4-dibutyl-2-phenyl-3,4-di­hydro­quinazoline

El-Hiti, G.A.; Smith, K.; Hegazy, A.S.; Alshammari, M.B.; Kariuki, B.M.

doi:10.1107/S1600536814020017

organic compounds

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Volume 70| Part 10| October 2014| Page o1100

doi:10.1107/S1600536814020017

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Crystal structure of 4,4-dibutyl-2-phenyl-3,4-dihydroquinazoline

Gamal A. El-Hiti,^a ^* Keith Smith,^b Amany S. Hegazy,^b Mohammed B. Alshammari ^c and Benson M. Kariuki ^b ^*

^aCornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, PO Box 10219, Riyadh 11433, Saudi Arabia, ^bSchool of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, Wales, and ^cChemistry Department, College of Sciences and Humanities, Salman bin Abdulaziz University, PO Box 83, Al-Kharij 11942, Saudi Arabia
^*Correspondence e-mail: gelhiti@ksu.edu.sa, kariukib@cardiff.ac.uk

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 4 September 2014; accepted 4 September 2014; online 10 September 2014)

In the title compound, C₂₂H₂₈N₂, the dihedral angle between the planes of the phenyl ring and the dihydroquinazoline ring system (r.m.s. deviation = 0.030 Å) is 24.95 (7)° and both n-butane chains assume all-trans conformations. In the crystal, N—H⋯N hydrogen bonds link the molecules into C(4) chains propagating in the [001] direction.

Keywords: crystal structure; quinazoline; hydrogen bonding.

CCDC reference: 1022964

1. Related literature

For the synthesis of 4,4-dibutyl-2-phenyl-3,4-dihydroquinazoline, see: Smith et al. (2005 ); Plé et al. (1997 ). For the crystal structures of related compounds, see Valkonen et al. (2011 ); Derabli et al. (2013 ).

2. Experimental

2.1. Crystal data

C₂₂H₂₈N₂
M_r = 320.46
Monoclinic, P 2₁ /c
a = 19.2953 (8) Å
b = 9.9889 (3) Å
c = 9.6341 (4) Å
β = 96.667 (4)°
V = 1844.31 (12) Å³
Z = 4
Cu Kα radiation
μ = 0.51 mm⁻¹
T = 150 K
0.41 × 0.13 × 0.04 mm

2.2. Data collection

SuperNova, Dual, Cu at zero, Atlas diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014 ) T_min = 0.829, T_max = 1.000
12894 measured reflections
3657 independent reflections
2866 reflections with I > 2σ(I)
R_int = 0.043

2.3. Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.129
S = 1.04
3657 reflections
219 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯N2ⁱ	0.88	2.29	3.1239 (16)	157
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and CHEMDRAW Ultra (Cambridge Soft, 2001 ); software used to prepare material for publication: SHELXL2013.

Supporting information

CCDC reference: 1022964

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536814020017/hb7281sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814020017/hb7281Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814020017/hb7281Isup3.cml

checkCIF report

Structural commentary top

In the molecule of C₂₂H₂₈N₂ (Fig. 1), the phenyl ring is twisted by 24.95 (7) from the plane of the dihydroquinazoline group. Both n-butane chains assume all-trans conformation. N—H···N hydrogen bonds between neigbouring molecules form chains parallel to the c-axis (Fig. 2).

4,4-Dibutyl-2-phenyl-3,4-dihydroquinazoline can be obtained from reaction of two mole equivalents of n-butyllithium with 4-(methylthio)-2-phenylquinazoline at –78°C in anhydrous THF [Smith et al. (2005); Plé et al. (1997)]. The reaction involves initial addition of n-butyllithium at the 4-position of quinazoline ring followed by elimination of methanethiolate anion and then further addition of n-butyllithium (Smith et al., 2005). For the X-ray structures of related compounds, see Valkonen et al. (2011); Derabli et al. (2013).

Synthesis and crystallization top

4,4-Dibutyl-2-phenyl-3,4-dihydroquinazoline

A solution of n-butyllithium in hexane (1.76 mL, 2.5 M, 4.4 mmol) was added to a cold (–78 ^οC), stirred solution of 4-(methylthio)-2-phenylquinazoline (0.50 g, 2.0 mmol) in anhydrous THF (10 mL) under N₂. The reaction mixture was stirred at –78 ^οC for 1 h then removed from the cooling bath and allowed to warm to room temperature, diluted with diethyl ether (10 mL), then quenched with aqueous saturated NH₄Cl (10 mL). The organic layer was separated, washed with water (2 x 10 mL), dried (MgSO₄), and evaporated under reduced pressure. The residue obtained was purified by column chromatography (silica gel; diethyl ether–hexane, 1:4 by volume) to give 4,4-dibutyl-2-phenyl-3,4-dihydroquinazoline in 96% yield, m.p. 161 ^οC [lit. 161 ^οC: Smith et al. (2005); 154–155 ^οC: Plé et al. (1997)]. Crystallization from a mixture of ethyl acetate and diethyl ether (1:3 by volume) gave the title compound as colorless crystals. The spectroscopic data for the title compound, including NMR and low and high resolution mass spectra, were consistent with those reported [Smith et al. (2005)].

Refinement top

H atoms were positioned geometrically and refined using a riding model, with U_iso(H) constrained to be 1.2 times U_eq for the bonded atom except for methyl groups where U_iso(H) was 1.5 times and free rotation about the C—C bond was allowed. Crystal data, data collection and structure refinement details are summarized in the table.

Related literature top

For the synthesis of 4,4-dibutyl-2-phenyl-3,4-dihydroquinazoline, see: Smith et al. (2005); Plé et al. (1997). For the crystal structures of related compounds, see Valkonen et al. (2011); Derabli et al. (2013).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and CHEMDRAW Ultra (Cambridge Soft, 2001); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008).

Figures top

	Fig. 1. The asymmetric unit of the title compound with 50% probability displacement ellipsoids.
	Fig. 2. Packing in the crystal structure showing N—H···N contacts as dotted lines with hydrogen atoms omitted for clarity.

4,4-Dibutyl-2-phenyl-3,4-dihydroquinazoline top

Crystal data top

C₂₂H₂₈N₂	F(000) = 696
M_r = 320.46	D_x = 1.154 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.5418 Å
a = 19.2953 (8) Å	Cell parameters from 3898 reflections
b = 9.9889 (3) Å	θ = 4.6–73.6°
c = 9.6341 (4) Å	µ = 0.51 mm⁻¹
β = 96.667 (4)°	T = 150 K
V = 1844.31 (12) Å³	Plate, colourless
Z = 4	0.41 × 0.13 × 0.04 mm

Data collection top

SuperNova, Dual, Cu at zero, Atlas diffractometer	2866 reflections with I > 2σ(I)
ω scans	R_int = 0.043
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	θ_max = 73.6°, θ_min = 4.6°
T_min = 0.829, T_max = 1.000	h = −23→23
12894 measured reflections	k = −12→12
3657 independent reflections	l = −11→11

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.047	H-atom parameters constrained
wR(F²) = 0.129	w = 1/[σ²(F_o²) + (0.0587P)² + 0.3637P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
3657 reflections	Δρ_max = 0.23 e Å⁻³
219 parameters	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₂₂H₂₈N₂	V = 1844.31 (12) Å³
M_r = 320.46	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 19.2953 (8) Å	µ = 0.51 mm⁻¹
b = 9.9889 (3) Å	T = 150 K
c = 9.6341 (4) Å	0.41 × 0.13 × 0.04 mm
β = 96.667 (4)°

Data collection top

SuperNova, Dual, Cu at zero, Atlas diffractometer	3657 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014)	2866 reflections with I > 2σ(I)
T_min = 0.829, T_max = 1.000	R_int = 0.043
12894 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.129	H-atom parameters constrained
S = 1.04	Δρ_max = 0.23 e Å⁻³
3657 reflections	Δρ_min = −0.17 e Å⁻³
219 parameters

Special details top

Experimental. Absorption correction: CrysAlisPro, Agilent Technologies, Version 1.171.36.28 (release 01-02-2013 CrysAlis171 .NET) (compiled Feb 1 2013,16:14:44) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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.

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

	x	y	z	U_iso*/U_eq
C1	0.28102 (8)	0.40404 (13)	0.14783 (14)	0.0259 (3)
C2	0.18929 (7)	0.30261 (13)	0.27980 (14)	0.0246 (3)
C3	0.26279 (8)	0.45814 (13)	0.39845 (15)	0.0272 (3)
C4	0.29777 (8)	0.48405 (13)	0.28214 (15)	0.0273 (3)
C5	0.28292 (9)	0.52724 (14)	0.52321 (16)	0.0314 (3)
H5	0.2592	0.5103	0.6025	0.038*
C6	0.33672 (9)	0.61972 (15)	0.53300 (17)	0.0356 (4)
H6	0.3500	0.6650	0.6187	0.043*
C7	0.37112 (9)	0.64606 (15)	0.41752 (18)	0.0358 (4)
H7	0.4078	0.7099	0.4232	0.043*
C8	0.35142 (8)	0.57829 (15)	0.29334 (17)	0.0326 (3)
H8	0.3750	0.5966	0.2142	0.039*
C9	0.12820 (8)	0.20985 (13)	0.27592 (14)	0.0259 (3)
C10	0.11781 (8)	0.10256 (14)	0.18380 (16)	0.0293 (3)
H10	0.1501	0.0869	0.1183	0.035*
C11	0.06087 (9)	0.01805 (15)	0.18637 (17)	0.0347 (4)
H11	0.0544	−0.0546	0.1225	0.042*
C12	0.01348 (9)	0.03893 (17)	0.28127 (18)	0.0369 (4)
H12	−0.0251	−0.0198	0.2837	0.044*
C13	0.02269 (9)	0.14620 (18)	0.37290 (18)	0.0399 (4)
H13	−0.0099	0.1616	0.4378	0.048*
C14	0.07937 (9)	0.23099 (16)	0.36999 (17)	0.0346 (4)
H14	0.0851	0.3045	0.4328	0.041*
C15	0.26253 (8)	0.49478 (14)	0.01923 (15)	0.0286 (3)
H15A	0.3044	0.5479	0.0049	0.034*
H15B	0.2520	0.4366	−0.0637	0.034*
C16	0.20181 (9)	0.59109 (15)	0.02432 (16)	0.0322 (3)
H16A	0.2107	0.6483	0.1084	0.039*
H16B	0.1586	0.5394	0.0319	0.039*
C17	0.19140 (8)	0.67945 (14)	−0.10553 (16)	0.0309 (3)
H17A	0.2352	0.7288	−0.1141	0.037*
H17B	0.1817	0.6217	−0.1891	0.037*
C18	0.13220 (9)	0.77946 (17)	−0.10306 (19)	0.0410 (4)
H18A	0.0880	0.7313	−0.1029	0.061*
H18B	0.1300	0.8369	−0.1859	0.061*
H18C	0.1404	0.8347	−0.0187	0.061*
C19	0.34439 (8)	0.31704 (14)	0.12029 (15)	0.0284 (3)
H19A	0.3305	0.2605	0.0373	0.034*
H19B	0.3820	0.3773	0.0966	0.034*
C20	0.37407 (8)	0.22668 (15)	0.23908 (16)	0.0322 (3)
H20A	0.3375	0.1632	0.2613	0.039*
H20B	0.3877	0.2818	0.3233	0.039*
C21	0.43742 (9)	0.14803 (16)	0.20321 (18)	0.0380 (4)
H21A	0.4249	0.0997	0.1141	0.046*
H21B	0.4755	0.2115	0.1894	0.046*
C22	0.46367 (11)	0.0478 (2)	0.3163 (2)	0.0534 (5)
H22A	0.4806	0.0958	0.4023	0.080*
H22B	0.5018	−0.0049	0.2851	0.080*
H22C	0.4255	−0.0121	0.3343	0.080*
N1	0.22079 (6)	0.31594 (12)	0.16295 (12)	0.0269 (3)
H1	0.2042	0.2684	0.0897	0.032*
N2	0.20764 (7)	0.36574 (12)	0.39726 (12)	0.0281 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0316 (8)	0.0222 (6)	0.0253 (7)	−0.0012 (5)	0.0088 (6)	0.0013 (5)
C2	0.0291 (7)	0.0207 (6)	0.0248 (7)	0.0044 (5)	0.0060 (5)	0.0031 (5)
C3	0.0328 (8)	0.0205 (6)	0.0285 (7)	0.0035 (5)	0.0049 (6)	0.0009 (5)
C4	0.0322 (7)	0.0201 (6)	0.0297 (7)	0.0024 (5)	0.0045 (6)	0.0022 (5)
C5	0.0408 (9)	0.0265 (7)	0.0273 (7)	0.0023 (6)	0.0054 (6)	−0.0007 (6)
C6	0.0445 (9)	0.0260 (7)	0.0349 (8)	0.0018 (6)	−0.0013 (7)	−0.0062 (6)
C7	0.0369 (9)	0.0247 (7)	0.0456 (9)	−0.0037 (6)	0.0032 (7)	−0.0020 (6)
C8	0.0376 (8)	0.0256 (7)	0.0357 (8)	−0.0009 (6)	0.0089 (7)	0.0010 (6)
C9	0.0297 (7)	0.0240 (6)	0.0243 (7)	0.0022 (5)	0.0049 (6)	0.0050 (5)
C10	0.0344 (8)	0.0264 (7)	0.0287 (7)	0.0016 (6)	0.0104 (6)	0.0019 (5)
C11	0.0389 (9)	0.0254 (7)	0.0404 (9)	−0.0018 (6)	0.0070 (7)	−0.0001 (6)
C12	0.0320 (8)	0.0353 (8)	0.0440 (9)	−0.0029 (6)	0.0068 (7)	0.0066 (7)
C13	0.0338 (9)	0.0490 (10)	0.0398 (9)	−0.0008 (7)	0.0168 (7)	−0.0003 (7)
C14	0.0366 (9)	0.0372 (8)	0.0313 (8)	0.0006 (6)	0.0101 (6)	−0.0039 (6)
C15	0.0349 (8)	0.0257 (7)	0.0265 (7)	−0.0016 (6)	0.0092 (6)	0.0023 (5)
C16	0.0378 (8)	0.0286 (7)	0.0313 (8)	0.0019 (6)	0.0083 (6)	0.0035 (6)
C17	0.0358 (8)	0.0264 (7)	0.0305 (8)	−0.0011 (6)	0.0036 (6)	0.0011 (6)
C18	0.0396 (9)	0.0356 (8)	0.0477 (10)	0.0043 (7)	0.0053 (7)	0.0087 (7)
C19	0.0334 (8)	0.0265 (7)	0.0267 (7)	−0.0005 (6)	0.0094 (6)	0.0009 (5)
C20	0.0380 (8)	0.0292 (7)	0.0301 (8)	0.0036 (6)	0.0075 (6)	0.0020 (6)
C21	0.0387 (9)	0.0322 (8)	0.0443 (9)	0.0047 (7)	0.0095 (7)	0.0024 (7)
C22	0.0478 (11)	0.0497 (11)	0.0628 (12)	0.0166 (9)	0.0060 (9)	0.0133 (9)
N1	0.0345 (7)	0.0247 (6)	0.0227 (6)	−0.0036 (5)	0.0084 (5)	−0.0009 (4)
N2	0.0352 (7)	0.0253 (6)	0.0248 (6)	−0.0012 (5)	0.0079 (5)	−0.0002 (5)

Geometric parameters (Å, º) top

C1—N1	1.4783 (18)	C13—H13	0.9500
C1—C4	1.523 (2)	C14—H14	0.9500
C1—C15	1.5432 (19)	C15—C16	1.521 (2)
C1—C19	1.5480 (19)	C15—H15A	0.9900
C2—N2	1.3079 (19)	C15—H15B	0.9900
C2—N1	1.3466 (18)	C16—C17	1.525 (2)
C2—C9	1.496 (2)	C16—H16A	0.9900
C3—C4	1.398 (2)	C16—H16B	0.9900
C3—C5	1.401 (2)	C17—C18	1.520 (2)
C3—N2	1.4078 (19)	C17—H17A	0.9900
C4—C8	1.394 (2)	C17—H17B	0.9900
C5—C6	1.385 (2)	C18—H18A	0.9800
C5—H5	0.9500	C18—H18B	0.9800
C6—C7	1.385 (2)	C18—H18C	0.9800
C6—H6	0.9500	C19—C20	1.517 (2)
C7—C8	1.389 (2)	C19—H19A	0.9900
C7—H7	0.9500	C19—H19B	0.9900
C8—H8	0.9500	C20—C21	1.526 (2)
C9—C10	1.391 (2)	C20—H20A	0.9900
C9—C14	1.397 (2)	C20—H20B	0.9900
C10—C11	1.388 (2)	C21—C22	1.523 (2)
C10—H10	0.9500	C21—H21A	0.9900
C11—C12	1.382 (2)	C21—H21B	0.9900
C11—H11	0.9500	C22—H22A	0.9800
C12—C13	1.387 (2)	C22—H22B	0.9800
C12—H12	0.9500	C22—H22C	0.9800
C13—C14	1.386 (2)	N1—H1	0.8800

N1—C1—C4	108.69 (11)	C1—C15—H15B	108.1
N1—C1—C15	108.52 (12)	H15A—C15—H15B	107.3
C4—C1—C15	112.35 (11)	C15—C16—C17	111.60 (12)
N1—C1—C19	109.17 (11)	C15—C16—H16A	109.3
C4—C1—C19	110.25 (12)	C17—C16—H16A	109.3
C15—C1—C19	107.80 (11)	C15—C16—H16B	109.3
N2—C2—N1	124.93 (13)	C17—C16—H16B	109.3
N2—C2—C9	116.96 (12)	H16A—C16—H16B	108.0
N1—C2—C9	118.10 (12)	C18—C17—C16	113.28 (13)
C4—C3—C5	119.01 (14)	C18—C17—H17A	108.9
C4—C3—N2	123.35 (13)	C16—C17—H17A	108.9
C5—C3—N2	117.64 (13)	C18—C17—H17B	108.9
C8—C4—C3	119.10 (14)	C16—C17—H17B	108.9
C8—C4—C1	120.17 (13)	H17A—C17—H17B	107.7
C3—C4—C1	120.61 (13)	C17—C18—H18A	109.5
C6—C5—C3	121.19 (14)	C17—C18—H18B	109.5
C6—C5—H5	119.4	H18A—C18—H18B	109.5
C3—C5—H5	119.4	C17—C18—H18C	109.5
C5—C6—C7	119.83 (15)	H18A—C18—H18C	109.5
C5—C6—H6	120.1	H18B—C18—H18C	109.5
C7—C6—H6	120.1	C20—C19—C1	116.19 (12)
C6—C7—C8	119.38 (15)	C20—C19—H19A	108.2
C6—C7—H7	120.3	C1—C19—H19A	108.2
C8—C7—H7	120.3	C20—C19—H19B	108.2
C7—C8—C4	121.49 (14)	C1—C19—H19B	108.2
C7—C8—H8	119.3	H19A—C19—H19B	107.4
C4—C8—H8	119.3	C19—C20—C21	112.19 (12)
C10—C9—C14	118.18 (14)	C19—C20—H20A	109.2
C10—C9—C2	123.21 (12)	C21—C20—H20A	109.2
C14—C9—C2	118.61 (13)	C19—C20—H20B	109.2
C11—C10—C9	120.86 (13)	C21—C20—H20B	109.2
C11—C10—H10	119.6	H20A—C20—H20B	107.9
C9—C10—H10	119.6	C22—C21—C20	112.66 (14)
C12—C11—C10	120.39 (15)	C22—C21—H21A	109.1
C12—C11—H11	119.8	C20—C21—H21A	109.1
C10—C11—H11	119.8	C22—C21—H21B	109.1
C11—C12—C13	119.48 (15)	C20—C21—H21B	109.1
C11—C12—H12	120.3	H21A—C21—H21B	107.8
C13—C12—H12	120.3	C21—C22—H22A	109.5
C14—C13—C12	120.16 (14)	C21—C22—H22B	109.5
C14—C13—H13	119.9	H22A—C22—H22B	109.5
C12—C13—H13	119.9	C21—C22—H22C	109.5
C13—C14—C9	120.92 (15)	H22A—C22—H22C	109.5
C13—C14—H14	119.5	H22B—C22—H22C	109.5
C9—C14—H14	119.5	C2—N1—C1	125.27 (12)
C16—C15—C1	116.92 (12)	C2—N1—H1	117.4
C16—C15—H15A	108.1	C1—N1—H1	117.4
C1—C15—H15A	108.1	C2—N2—C3	116.84 (12)
C16—C15—H15B	108.1

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2ⁱ	0.88	2.29	3.1239 (16)	157

Symmetry code: (i) x, −y+1/2, z−1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2ⁱ	0.88	2.29	3.1239 (16)	157

Symmetry code: (i) x, −y+1/2, z−1/2.

Acknowledgements

This project was supported by the Deanship of Scientific Research at Salman bin Abdulaziz University under research project 2013/01/8.

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