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In the title compound, C19H21N3O2, the pyrazolone ring and the attached C—NH group are essentially coplanar. The compound is in an enamine–keto form and its structure is stabilized by one strong intra­molecular N—H...O hydrogen bond.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807034216/hg2259sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807034216/hg2259Isup2.hkl
Contains datablock I

CCDC reference: 657795

Key indicators

  • Single-crystal X-ray study
  • T = 295 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.047
  • wR factor = 0.128
  • Data-to-parameter ratio = 18.9

checkCIF/PLATON results

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Alert level C PLAT153_ALERT_1_C The su's on the Cell Axes are Equal (x 100000) 60 Ang. PLAT230_ALERT_2_C Hirshfeld Test Diff for C14 - C15 .. 5.70 su
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check

Comment top

4-Acylpyrazolones are an interesting class of β-diketones, containing a pyrazole-bearing chelating arm. Thus, their metal complexes are used for the separation of elements with similar properties (Nishihama et al., 2001). 1-phenyl-3-methyl-4-(2-furoyl)-5-pyrazolone(HPMFP), is a member of a family of 4-heterocyclic acylpyrazolones, first synthesized in 1983 (Dong et al., 1983). In recent years, we have reported the Schiff bases derived from HPMFP and its complexes, which possess high antibacterial activation(Li et al., 1997; Li et al., 2000). Knowledge of the crystal structure of such 4-heterocyclic acylpyrazolones derivatives gives us not only information about nuclearity of the complex molecule, but is important in understanding the behaviour of this compounds in the vapour phase, and the mechanisms of sublimation and decomposition. Therefore, we have synthesized the title compound, (I), and report its crystal structure here.

The molecular structure of (I) is shown in Fig.1. Atoms O1, C7, C8 and C11 of the PMFP moiety and atom N3 of n-butylamine group are coplanar, the largest deviation being 0.0417 (11)Å for atom C11. The dihedral angle between this mean plane and pyrazole ring of PMFP is 3.35 (3)°. The bond length of C8—C11 (1.393 (2) Å) between the usual C—C and C=C bonds indicates the delocalization of the electrons because of the addition of a proton to N3 is more favorable than to O2. The atom O2 of 1-phenyl-3-methyl-4-(α-furoyl)-pyrazolone-5 moiety and the N3 atom of the n-butylamine group are on the same side of C8—C11 bond, which are available for coordination with metal cations. A strong intramolecular hydrogen bond N3—H3A···O1 (Table 1) is also indicative of the enamine-keto form. Another intramolecular hydrogen bond(C2—H2···O1) and an intermolelular hydrogen bond [C15—H15···O1i; symmetry code(i): x, –y+1/2, z + 1/2] are also found, stabilizing the structure.

Related literature top

For general background, see: Dong et al. (1983); Jensen (1959); Li et al. (1997, 2000); Nishihama et al. (2001).

Experimental top

HPMFP was synthesized according to the method proposed by Jensen (1959). A mixture of a 10 ml HPMFP (2 mmol, 0.5366 g) anhydrous ethanol solution, and a 0.2 ml n-butylamine (2 mmol, 0.1463 g) solution was refluxed for ca. 5 h, with addition of a few drops of glacial acetic acid as a catalyst. The ethanol was removed by evaporation and the resulting green precipitate formed was filtered off, washed with cold anhydrous ethanol and dried in air. Green block single crystals suitable for analysis were obtained by slow evaporation of a solution in anhydrous ethanol at room temperature for a few days.

Refinement top

The H atom bonded to N3 was located in a difference map and refined freely. Other H atoms were placed in calculated positions, with C—H = 0.93Å for phenyl, 0.96Å for methyl and 0.97Å for methylene H atoms,and refined as riding, with Uiso(H)=1.2Ueq (C) for phenyl and methylene H, and 1.5eqU(C) for methyl H.

Structure description top

4-Acylpyrazolones are an interesting class of β-diketones, containing a pyrazole-bearing chelating arm. Thus, their metal complexes are used for the separation of elements with similar properties (Nishihama et al., 2001). 1-phenyl-3-methyl-4-(2-furoyl)-5-pyrazolone(HPMFP), is a member of a family of 4-heterocyclic acylpyrazolones, first synthesized in 1983 (Dong et al., 1983). In recent years, we have reported the Schiff bases derived from HPMFP and its complexes, which possess high antibacterial activation(Li et al., 1997; Li et al., 2000). Knowledge of the crystal structure of such 4-heterocyclic acylpyrazolones derivatives gives us not only information about nuclearity of the complex molecule, but is important in understanding the behaviour of this compounds in the vapour phase, and the mechanisms of sublimation and decomposition. Therefore, we have synthesized the title compound, (I), and report its crystal structure here.

The molecular structure of (I) is shown in Fig.1. Atoms O1, C7, C8 and C11 of the PMFP moiety and atom N3 of n-butylamine group are coplanar, the largest deviation being 0.0417 (11)Å for atom C11. The dihedral angle between this mean plane and pyrazole ring of PMFP is 3.35 (3)°. The bond length of C8—C11 (1.393 (2) Å) between the usual C—C and C=C bonds indicates the delocalization of the electrons because of the addition of a proton to N3 is more favorable than to O2. The atom O2 of 1-phenyl-3-methyl-4-(α-furoyl)-pyrazolone-5 moiety and the N3 atom of the n-butylamine group are on the same side of C8—C11 bond, which are available for coordination with metal cations. A strong intramolecular hydrogen bond N3—H3A···O1 (Table 1) is also indicative of the enamine-keto form. Another intramolecular hydrogen bond(C2—H2···O1) and an intermolelular hydrogen bond [C15—H15···O1i; symmetry code(i): x, –y+1/2, z + 1/2] are also found, stabilizing the structure.

For general background, see: Dong et al. (1983); Jensen (1959); Li et al. (1997, 2000); Nishihama et al. (2001).

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SMART; data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS86 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) (thermal ellipsoids are shown at 30% probability levels).
4-[(Z)-(n-Butylamino)(2-furyl)methylene]-3-methyl-1-phenyl- 1H-pyrazol-5(4H)-one top
Crystal data top
C19H21N3O2F(000) = 1376
Mr = 323.39Dx = 1.260 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 3467 reflections
a = 15.1910 (6) Åθ = 2.6–21.8°
b = 14.5509 (6) ŵ = 0.08 mm1
c = 15.4249 (6) ÅT = 295 K
V = 3409.6 (2) Å3Block, green
Z = 80.26 × 0.20 × 0.18 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
4225 independent reflections
Radiation source: fine-focus sealed tube2326 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.060
φ and ω scansθmax = 28.3°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2005)
h = 2020
Tmin = 0.884, Tmax = 0.980k = 1919
32853 measured reflectionsl = 2020
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0533P)2 + 0.4662P]
where P = (Fo2 + 2Fc2)/3
4225 reflections(Δ/σ)max < 0.001
223 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C19H21N3O2V = 3409.6 (2) Å3
Mr = 323.39Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 15.1910 (6) ŵ = 0.08 mm1
b = 14.5509 (6) ÅT = 295 K
c = 15.4249 (6) Å0.26 × 0.20 × 0.18 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
4225 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2005)
2326 reflections with I > 2σ(I)
Tmin = 0.884, Tmax = 0.980Rint = 0.060
32853 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0470 restraints
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.16 e Å3
4225 reflectionsΔρmin = 0.19 e Å3
223 parameters
Special details top

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.

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
xyzUiso*/Ueq
O10.06704 (8)0.13250 (9)0.41864 (8)0.0560 (3)
N20.25340 (9)0.11806 (10)0.55284 (9)0.0499 (4)
C80.10515 (10)0.11395 (11)0.57046 (11)0.0431 (4)
O20.03838 (8)0.17852 (8)0.74500 (8)0.0536 (3)
N10.21209 (9)0.13090 (9)0.47231 (9)0.0475 (4)
N30.04887 (9)0.10498 (10)0.55306 (11)0.0493 (4)
C120.00469 (10)0.10627 (11)0.69884 (11)0.0446 (4)
C170.20167 (11)0.12292 (12)0.50373 (11)0.0475 (4)
H17A0.19010.07830.45840.057*
H17B0.18980.18360.48050.057*
C110.02069 (10)0.10832 (11)0.60525 (11)0.0429 (4)
C10.26506 (11)0.14257 (11)0.39802 (11)0.0470 (4)
C180.29717 (11)0.11681 (13)0.53097 (12)0.0542 (5)
H18A0.30890.16440.57350.065*
H18B0.30700.05790.55880.065*
C90.19055 (10)0.10845 (11)0.61015 (11)0.0446 (4)
C70.12121 (11)0.12670 (11)0.47977 (11)0.0452 (4)
C60.35621 (12)0.13823 (13)0.40621 (13)0.0599 (5)
H60.38160.12760.46020.072*
C160.14156 (10)0.10485 (12)0.57981 (11)0.0488 (4)
H16A0.15070.15180.62360.059*
H16B0.15600.04580.60530.059*
C20.22899 (13)0.15950 (13)0.31758 (12)0.0593 (5)
H20.16820.16320.31120.071*
C150.01642 (12)0.16258 (14)0.82933 (12)0.0600 (5)
H150.03060.20120.87530.072*
C130.03612 (12)0.04813 (14)0.75253 (13)0.0611 (5)
H130.06460.00610.73720.073*
C100.21496 (12)0.08888 (14)0.70213 (11)0.0590 (5)
H10A0.27710.07760.70580.088*
H10B0.18340.03570.72200.088*
H10C0.20000.14080.73760.088*
C190.36167 (13)0.12711 (15)0.45664 (14)0.0694 (6)
H19A0.35580.18720.43160.104*
H19B0.42060.11920.47780.104*
H19C0.34950.08140.41330.104*
C50.40876 (14)0.14969 (15)0.33424 (14)0.0702 (6)
H50.46960.14660.34020.084*
C140.02789 (14)0.08449 (15)0.83679 (13)0.0688 (6)
H140.04940.05870.88770.083*
C40.37335 (14)0.16551 (14)0.25431 (14)0.0697 (6)
H40.40950.17240.20610.084*
C30.28342 (15)0.17102 (15)0.24630 (13)0.0693 (6)
H30.25870.18270.19220.083*
H3A0.0361 (12)0.1030 (12)0.4967 (13)0.064 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0414 (7)0.0769 (9)0.0497 (8)0.0025 (6)0.0059 (6)0.0046 (6)
N20.0399 (8)0.0599 (9)0.0499 (9)0.0007 (7)0.0033 (7)0.0006 (7)
C80.0357 (9)0.0468 (10)0.0469 (10)0.0019 (7)0.0011 (7)0.0011 (7)
O20.0520 (7)0.0551 (7)0.0536 (8)0.0024 (6)0.0030 (6)0.0066 (6)
N10.0381 (8)0.0576 (9)0.0466 (9)0.0006 (6)0.0007 (6)0.0015 (6)
N30.0367 (8)0.0660 (10)0.0453 (9)0.0018 (7)0.0008 (7)0.0032 (7)
C120.0359 (9)0.0491 (9)0.0488 (10)0.0003 (7)0.0040 (7)0.0028 (8)
C170.0380 (9)0.0528 (10)0.0516 (10)0.0018 (8)0.0029 (8)0.0054 (8)
C110.0373 (9)0.0415 (9)0.0499 (10)0.0027 (7)0.0038 (8)0.0014 (7)
C10.0445 (10)0.0463 (10)0.0502 (10)0.0018 (7)0.0043 (8)0.0017 (8)
C180.0392 (10)0.0598 (12)0.0635 (12)0.0014 (8)0.0033 (8)0.0013 (9)
C90.0378 (9)0.0471 (10)0.0488 (10)0.0012 (7)0.0017 (8)0.0003 (8)
C70.0379 (9)0.0456 (9)0.0521 (11)0.0020 (7)0.0023 (8)0.0002 (8)
C60.0462 (11)0.0714 (13)0.0620 (12)0.0004 (9)0.0045 (9)0.0099 (10)
C160.0357 (9)0.0586 (11)0.0523 (11)0.0010 (8)0.0005 (8)0.0026 (8)
C20.0520 (11)0.0724 (13)0.0536 (12)0.0025 (9)0.0034 (9)0.0050 (9)
C150.0549 (11)0.0806 (14)0.0445 (11)0.0075 (10)0.0050 (9)0.0094 (10)
C130.0615 (12)0.0687 (12)0.0531 (12)0.0185 (10)0.0049 (10)0.0037 (10)
C100.0428 (10)0.0812 (14)0.0530 (12)0.0065 (9)0.0070 (8)0.0047 (10)
C190.0436 (11)0.0901 (15)0.0745 (14)0.0001 (10)0.0103 (10)0.0080 (11)
C50.0499 (12)0.0837 (15)0.0771 (16)0.0035 (10)0.0138 (11)0.0048 (11)
C140.0635 (13)0.0914 (16)0.0514 (13)0.0126 (12)0.0007 (10)0.0080 (11)
C40.0657 (14)0.0785 (14)0.0648 (14)0.0132 (11)0.0212 (11)0.0046 (11)
C30.0768 (15)0.0825 (15)0.0487 (12)0.0076 (12)0.0050 (11)0.0034 (10)
Geometric parameters (Å, º) top
O1—C71.2544 (19)C9—C101.494 (2)
N2—C91.309 (2)C7—O11.2544 (19)
N2—N11.4041 (19)C6—C51.377 (3)
C8—C111.393 (2)C6—H60.9300
C8—C71.432 (2)C16—H16A0.9700
C8—C91.437 (2)C16—H16B0.9700
O2—C151.363 (2)C2—C31.386 (3)
O2—C121.3690 (19)C2—H20.9300
N1—C71.387 (2)C15—C141.326 (3)
N1—C11.410 (2)C15—H150.9300
N3—C111.329 (2)C13—C141.409 (3)
N3—C161.467 (2)C13—H130.9300
N3—H3A0.891 (19)C10—H10A0.9600
C12—C131.336 (2)C10—H10B0.9600
C12—C111.464 (2)C10—H10C0.9600
C17—C161.510 (2)C19—H19A0.9600
C17—C181.513 (2)C19—H19B0.9600
C17—H17A0.9700C19—H19C0.9600
C17—H17B0.9700C5—C41.365 (3)
C1—C21.379 (2)C5—H50.9300
C1—C61.392 (2)C14—H140.9300
C18—C191.516 (3)C4—C31.374 (3)
C18—H18A0.9700C4—H40.9300
C18—H18B0.9700C3—H30.9300
C9—N2—N1106.61 (14)C1—C6—H6120.1
C11—C8—C7122.74 (15)N3—C16—C17111.20 (14)
C11—C8—C9131.62 (15)N3—C16—H16A109.4
C7—C8—C9105.64 (14)C17—C16—H16A109.4
C15—O2—C12105.91 (14)N3—C16—H16B109.4
C7—N1—N2111.45 (13)C17—C16—H16B109.4
C7—N1—C1129.85 (15)H16A—C16—H16B108.0
N2—N1—C1118.67 (14)C1—C2—C3119.90 (19)
C11—N3—C16126.34 (16)C1—C2—H2120.0
C11—N3—H3A114.8 (12)C3—C2—H2120.0
C16—N3—H3A118.9 (12)C14—C15—O2110.68 (17)
C13—C12—O2109.71 (16)C14—C15—H15124.7
C13—C12—C11134.50 (16)O2—C15—H15124.7
O2—C12—C11115.79 (14)C12—C13—C14107.03 (17)
C16—C17—C18110.72 (15)C12—C13—H13126.5
C16—C17—H17A109.5C14—C13—H13126.5
C18—C17—H17A109.5C9—C10—H10A109.5
C16—C17—H17B109.5C9—C10—H10B109.5
C18—C17—H17B109.5H10A—C10—H10B109.5
H17A—C17—H17B108.1C9—C10—H10C109.5
N3—C11—C8120.06 (16)H10A—C10—H10C109.5
N3—C11—C12117.67 (15)H10B—C10—H10C109.5
C8—C11—C12122.26 (14)C18—C19—H19A109.5
C2—C1—C6119.02 (17)C18—C19—H19B109.5
C2—C1—N1121.73 (16)H19A—C19—H19B109.5
C6—C1—N1119.24 (16)C18—C19—H19C109.5
C17—C18—C19113.83 (17)H19A—C19—H19C109.5
C17—C18—H18A108.8H19B—C19—H19C109.5
C19—C18—H18A108.8C4—C5—C6121.3 (2)
C17—C18—H18B108.8C4—C5—H5119.3
C19—C18—H18B108.8C6—C5—H5119.3
H18A—C18—H18B107.7C15—C14—C13106.66 (18)
N2—C9—C8111.41 (15)C15—C14—H14126.7
N2—C9—C10118.75 (15)C13—C14—H14126.7
C8—C9—C10129.75 (15)C5—C4—C3118.89 (19)
O1—C7—N1126.00 (16)C5—C4—H4120.6
O1—C7—C8129.15 (15)C3—C4—H4120.6
N1—C7—C8104.86 (14)C4—C3—C2121.0 (2)
C5—C6—C1119.87 (19)C4—C3—H3119.5
C5—C6—H6120.1C2—C3—H3119.5
C9—N2—N1—C71.61 (18)N2—N1—C7—O1177.39 (15)
C9—N2—N1—C1179.57 (14)C1—N1—C7—O10.3 (3)
C15—O2—C12—C130.15 (19)N2—N1—C7—O1177.39 (15)
C15—O2—C12—C11179.74 (14)C1—N1—C7—O10.3 (3)
C16—N3—C11—C8175.87 (15)N2—N1—C7—C82.20 (18)
C16—N3—C11—C123.9 (2)C1—N1—C7—C8179.87 (15)
C7—C8—C11—N37.2 (2)C11—C8—C7—O11.9 (3)
C9—C8—C11—N3172.23 (16)C9—C8—C7—O1177.67 (17)
C7—C8—C11—C12172.57 (15)C11—C8—C7—O11.9 (3)
C9—C8—C11—C128.0 (3)C9—C8—C7—O1177.67 (17)
C13—C12—C11—N357.2 (3)C11—C8—C7—N1178.57 (14)
O2—C12—C11—N3123.33 (16)C9—C8—C7—N11.90 (17)
C13—C12—C11—C8123.1 (2)C2—C1—C6—C50.8 (3)
O2—C12—C11—C856.4 (2)N1—C1—C6—C5179.87 (17)
C7—N1—C1—C25.4 (3)C11—N3—C16—C17166.66 (16)
N2—N1—C1—C2177.10 (16)C18—C17—C16—N3176.50 (14)
C7—N1—C1—C6175.58 (16)C6—C1—C2—C30.6 (3)
N2—N1—C1—C61.9 (2)N1—C1—C2—C3179.66 (17)
C16—C17—C18—C19175.67 (15)C12—O2—C15—C140.5 (2)
N1—N2—C9—C80.30 (18)O2—C12—C13—C140.3 (2)
N1—N2—C9—C10176.99 (15)C11—C12—C13—C14179.22 (18)
C11—C8—C9—N2179.51 (16)C1—C6—C5—C40.1 (3)
C7—C8—C9—N21.03 (19)O2—C15—C14—C130.7 (2)
C11—C8—C9—C104.3 (3)C12—C13—C14—C150.6 (2)
C7—C8—C9—C10175.19 (18)C6—C5—C4—C30.7 (3)
O1—O1—C7—N10.00 (9)C5—C4—C3—C20.9 (3)
O1—O1—C7—C80.00 (5)C1—C2—C3—C40.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O10.891 (19)2.022 (19)2.750 (2)138.0 (16)
C2—H2···O10.932.302.939 (2)125
C15—H15···O1i0.932.573.374 (2)145
Symmetry code: (i) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC19H21N3O2
Mr323.39
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)295
a, b, c (Å)15.1910 (6), 14.5509 (6), 15.4249 (6)
V3)3409.6 (2)
Z8
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.26 × 0.20 × 0.18
Data collection
DiffractometerBruker SMART CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2005)
Tmin, Tmax0.884, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
32853, 4225, 2326
Rint0.060
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.047, 0.128, 1.00
No. of reflections4225
No. of parameters223
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.16, 0.19

Computer programs: SMART (Bruker, 2005), SMART, SAINT (Bruker, 2005), SHELXS86 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2001), SHELXTL.

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···O10.891 (19)2.022 (19)2.750 (2)138.0 (16)
C2—H2···O10.932.302.939 (2)125.0
C15—H15···O1i0.932.573.374 (2)144.7
Symmetry code: (i) x, y+1/2, z+1/2.
 

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