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ISSN: 2056-9890

3,6-Di­methyl-1-phenyl-1H,4H-pyrano[2,3-c]pyrazol-4-one

aChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah, Saudi Arabia, bThe Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, PO Box 80203, Saudi Arabia, and cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 13 March 2012; accepted 15 March 2012; online 21 March 2012)

The title compound, C14H12N2O2, is almost planar with an r.m.s. deviation for all non-H atoms of 0.038 Å. The observed planarity is rationalized in terms of a close intra­molecular C—H⋯O inter­action. Supra­molecular layers, two mol­ecules thick and with a step topology, are formed in the crystal packing via C—H⋯O contacts involving the carbonyl O atom, which accepts two such bonds, and ππ inter­actions between the components of the fused ring system and the phenyl ring of inversion-related mol­ecules [centroid–centroid distances = 3.6819 (13) and 3.6759 (12) Å].

Related literature

For the analgesic and anti-inflammatory activities of pyrano[2,3-c]pyrazole derivatives, see: Kuo et al. (1984[Kuo, S.-C., Huang, L.-J. & Nakamura, H. (1984). J. Med. Chem. 27, 539-544.]). For the synthesis, see: Gelin et al. (1983[Gelin, S., Chantegrel, B. & Nadi, A. I. (1983). J. Org. Chem. 48, 4078-4082.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12N2O2

  • Mr = 240.26

  • Triclinic, [P \overline 1]

  • a = 6.7200 (6) Å

  • b = 8.2201 (8) Å

  • c = 11.2616 (7) Å

  • α = 93.914 (6)°

  • β = 95.162 (6)°

  • γ = 108.721 (8)°

  • V = 583.66 (9) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.40 × 0.30 × 0.20 mm

Data collection
  • Agilent SuperNova Dual diffractometer with an Atlas detector

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.964, Tmax = 0.982

  • 4356 measured reflections

  • 2676 independent reflections

  • 1946 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.158

  • S = 1.05

  • 2676 reflections

  • 165 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.38 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10⋯O1 0.95 2.33 2.970 (2) 124
C3—H3⋯O2i 0.95 2.47 3.400 (3) 167
C8—H8C⋯O2ii 0.98 2.54 3.472 (3) 158
Symmetry codes: (i) -x+1, -y, -z; (ii) -x+2, -y+1, -z.

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

It has been reported that many pyrano[2,3-c]pyrazole derivatives possess analgesic and anti-inflammatory activities (Kuo et al., 1984). In this report, following literature precedents (Gelin et al., 1983; Kuo et al., 1984), the title compound was synthesized, and herein, its crystal and molecular structure are described.

In the title molecule, Fig.1, each of the pyrazole [r.m.s. deviation = 0.001 Å] and pyran-4-one [r.m.s. deviation = 0.006 Å] rings is planar and the dihedral angle between them is 0.82 (11)°. The planarity in the molecule extends to include the pendent phenyl ring, which makes a dihedral angle of 3.17 (11)° with the pyrazole ring. The r.m.s. deviation for the 18 non-hydrogen atoms is 0.038 Å, with maximum deviations of 0.071 (2) Å for atoms C13 and C14, and -0.059 (2) Å for the C10 atom. An explanation for the co-planarity in the molecule is the presence of intramolecular C10—H···O1 and C14—H14···N2 interactions (Table 1).

In the crystal packing, the carbonyl-O2 atom is bifurcated, forming two C—H···O interactions (Table 1 and Fig. 2), leading to a supramolecular layer in the bc plane. Layers are connected into double layers by ππ interactions involving the phenyl ring interacting with both rings of the fused ring system [ring centroid···ring centroid distances = 3.6819 (13) Å, for the five- and six-membered rings, and 3.6759 (12) Å, for the interaction between the two six-membered rings; symmetry operation: -x+2, -y+1, -z+1]. The layers have a step topology and stack along the a axis with no specific intermolecular interactions between them (Fig. 3).

Related literature top

For the analgesic and anti-inflammatory activities of pyrano[2,3-c]pyrazole derivatives, see: Kuo et al. (1984). For the synthesis, see: Gelin et al. (1983).

Experimental top

Following literature precedents (Gelin et al., 1983; Kuo et al., 1984), dehydroacetic acid was converted to 4-acetoacetyl-3-methyl-1-phenyl-2-pyrazolin-5-one, which in turn yielded 3,6-dimethyl-1-phenyl-1H,3aH,4H,7aH-pyrano[2,3-c]pyrazol-4-one when treated with concentrated sulfuric acid.

To a solution of dehydroacetic acid (10 mmol) in benzene (20 ml) was added the phenylhydrazine (10 mmol). The mixture was refluxed for 30 min and allowed to stand at room temperature for 2 h. After the mixture was cooled, the hydrazone was collected and recrystallized from ethanol. A solution of this product (10 mmol) in acetic acid (20 ml) was refluxed for 1 h. After evaporation of the solvent, the residue was recrystallized from ethanol as needles. To a solution of this (2.5 g, 0.01 mmol), i.e. 4-acetoacetyl-3-methyl-1-phenyl-2-pyrazolin-5-one, in acetic acid (20 ml) was added concentrated sulfuric acid (1 ml) drop wise. The mixture was poured into cold water (150 ml) and the resulting precipitate was filtered, washed with 5% aqueous Na2CO3 solution, water, dried and recrystallized from ethanol. Yield: 74%. M.pt: 426–427 K.

Refinement top

Carbon-bound H-atoms were placed in calculated positions and were treated as riding atoms: C—H = 0.95 and 0.98 Å for CH and CH3 H atoms, respectively, with Uiso(H) = k × Ueq(C), where k = 1.5 for CH3 H atoms, and = 1.2 for other H atoms.

Structure description top

It has been reported that many pyrano[2,3-c]pyrazole derivatives possess analgesic and anti-inflammatory activities (Kuo et al., 1984). In this report, following literature precedents (Gelin et al., 1983; Kuo et al., 1984), the title compound was synthesized, and herein, its crystal and molecular structure are described.

In the title molecule, Fig.1, each of the pyrazole [r.m.s. deviation = 0.001 Å] and pyran-4-one [r.m.s. deviation = 0.006 Å] rings is planar and the dihedral angle between them is 0.82 (11)°. The planarity in the molecule extends to include the pendent phenyl ring, which makes a dihedral angle of 3.17 (11)° with the pyrazole ring. The r.m.s. deviation for the 18 non-hydrogen atoms is 0.038 Å, with maximum deviations of 0.071 (2) Å for atoms C13 and C14, and -0.059 (2) Å for the C10 atom. An explanation for the co-planarity in the molecule is the presence of intramolecular C10—H···O1 and C14—H14···N2 interactions (Table 1).

In the crystal packing, the carbonyl-O2 atom is bifurcated, forming two C—H···O interactions (Table 1 and Fig. 2), leading to a supramolecular layer in the bc plane. Layers are connected into double layers by ππ interactions involving the phenyl ring interacting with both rings of the fused ring system [ring centroid···ring centroid distances = 3.6819 (13) Å, for the five- and six-membered rings, and 3.6759 (12) Å, for the interaction between the two six-membered rings; symmetry operation: -x+2, -y+1, -z+1]. The layers have a step topology and stack along the a axis with no specific intermolecular interactions between them (Fig. 3).

For the analgesic and anti-inflammatory activities of pyrano[2,3-c]pyrazole derivatives, see: Kuo et al. (1984). For the synthesis, see: Gelin et al. (1983).

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
[Figure 1] Fig. 1. The molecular structure of the title molecule showing the atom-labelling. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A view of the supramolecular layer in the bc plane in the crystal structure of the title compound. The O—H···O and ππ interactions are shown as orange and purple dashed lines, respectively.
[Figure 3] Fig. 3. A view in projection down the c axis of the unit-cell contents of the title compound. The O—H···O and ππ interactions are shown as orange and purple dashed lines, respectively.
3,6-Dimethyl-1-phenyl-1H,4H-pyrano[2,3-c]pyrazol-4-one top
Crystal data top
C14H12N2O2Z = 2
Mr = 240.26F(000) = 252
Triclinic, P1Dx = 1.367 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.7200 (6) ÅCell parameters from 1310 reflections
b = 8.2201 (8) Åθ = 2.6–27.5°
c = 11.2616 (7) ŵ = 0.09 mm1
α = 93.914 (6)°T = 100 K
β = 95.162 (6)°Prism, orange
γ = 108.721 (8)°0.40 × 0.30 × 0.20 mm
V = 583.66 (9) Å3
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2676 independent reflections
Radiation source: SuperNova (Mo) X-ray Source1946 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.031
Detector resolution: 10.4041 pixels mm-1θmax = 27.6°, θmin = 2.6°
ω scanh = 88
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
k = 109
Tmin = 0.964, Tmax = 0.982l = 1414
4356 measured reflections
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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.158H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0761P)2 + 0.084P]
where P = (Fo2 + 2Fc2)/3
2676 reflections(Δ/σ)max = 0.001
165 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.38 e Å3
Crystal data top
C14H12N2O2γ = 108.721 (8)°
Mr = 240.26V = 583.66 (9) Å3
Triclinic, P1Z = 2
a = 6.7200 (6) ÅMo Kα radiation
b = 8.2201 (8) ŵ = 0.09 mm1
c = 11.2616 (7) ÅT = 100 K
α = 93.914 (6)°0.40 × 0.30 × 0.20 mm
β = 95.162 (6)°
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2676 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
1946 reflections with I > 2σ(I)
Tmin = 0.964, Tmax = 0.982Rint = 0.031
4356 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.158H-atom parameters constrained
S = 1.05Δρmax = 0.34 e Å3
2676 reflectionsΔρmin = 0.38 e Å3
165 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.6182 (2)0.25349 (16)0.35598 (11)0.0238 (3)
O20.6446 (2)0.28672 (19)0.00902 (12)0.0349 (4)
N10.7795 (2)0.55863 (19)0.37569 (13)0.0216 (4)
N20.8481 (3)0.6876 (2)0.30000 (14)0.0257 (4)
C10.4637 (3)0.0519 (3)0.33142 (18)0.0336 (5)
H1A0.40580.15140.27060.050*
H1B0.35230.04280.37930.050*
H1C0.57970.06710.38380.050*
C20.5447 (3)0.1084 (2)0.27152 (17)0.0266 (4)
C30.5520 (3)0.1187 (3)0.15402 (17)0.0284 (5)
H30.49760.01450.10200.034*
C40.6380 (3)0.2797 (3)0.10026 (17)0.0276 (5)
C50.7110 (3)0.4278 (2)0.18953 (16)0.0245 (4)
C60.6979 (3)0.4044 (2)0.30916 (16)0.0221 (4)
C70.8072 (3)0.6086 (3)0.18951 (17)0.0266 (4)
C80.8643 (4)0.7086 (3)0.08486 (18)0.0339 (5)
H8A0.91060.83240.11120.051*
H8B0.74060.67890.02430.051*
H8C0.97920.68010.05020.051*
C90.8063 (3)0.6061 (2)0.50196 (16)0.0221 (4)
C100.7333 (3)0.4863 (2)0.58291 (17)0.0262 (4)
H100.66430.36780.55540.031*
C110.7627 (3)0.5423 (3)0.70503 (17)0.0261 (4)
H110.71320.46130.76090.031*
C120.8638 (3)0.7155 (3)0.74549 (17)0.0262 (4)
H120.88260.75290.82870.031*
C130.9367 (3)0.8327 (3)0.66445 (17)0.0269 (4)
H131.00620.95110.69220.032*
C140.9096 (3)0.7798 (2)0.54306 (17)0.0259 (4)
H140.96110.86130.48780.031*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0281 (7)0.0183 (7)0.0214 (7)0.0041 (5)0.0027 (5)0.0041 (5)
O20.0417 (9)0.0379 (9)0.0209 (7)0.0093 (7)0.0037 (6)0.0068 (6)
N10.0251 (8)0.0193 (8)0.0177 (8)0.0049 (6)0.0014 (6)0.0039 (6)
N20.0310 (9)0.0230 (8)0.0214 (8)0.0064 (7)0.0042 (6)0.0004 (7)
C10.0416 (13)0.0218 (11)0.0314 (11)0.0035 (9)0.0046 (9)0.0050 (9)
C20.0272 (10)0.0194 (10)0.0277 (10)0.0035 (8)0.0003 (8)0.0092 (8)
C30.0299 (11)0.0264 (11)0.0255 (10)0.0075 (8)0.0007 (8)0.0086 (8)
C40.0263 (10)0.0290 (11)0.0241 (10)0.0074 (8)0.0002 (8)0.0073 (8)
C50.0253 (10)0.0253 (10)0.0214 (10)0.0079 (8)0.0019 (7)0.0033 (8)
C60.0213 (9)0.0201 (9)0.0232 (9)0.0061 (7)0.0014 (7)0.0036 (7)
C70.0280 (10)0.0278 (10)0.0227 (10)0.0083 (8)0.0037 (7)0.0023 (8)
C80.0439 (13)0.0326 (12)0.0229 (10)0.0091 (10)0.0066 (9)0.0014 (9)
C90.0229 (9)0.0237 (10)0.0183 (9)0.0079 (8)0.0005 (7)0.0049 (7)
C100.0295 (10)0.0215 (10)0.0243 (10)0.0057 (8)0.0018 (8)0.0048 (8)
C110.0309 (11)0.0252 (10)0.0220 (10)0.0089 (8)0.0042 (8)0.0007 (8)
C120.0291 (10)0.0283 (11)0.0194 (9)0.0092 (8)0.0003 (7)0.0060 (8)
C130.0302 (10)0.0216 (10)0.0241 (10)0.0047 (8)0.0014 (8)0.0069 (8)
C140.0306 (11)0.0227 (10)0.0215 (10)0.0055 (8)0.0033 (8)0.0019 (8)
Geometric parameters (Å, º) top
O1—C61.348 (2)C5—C71.418 (3)
O1—C21.397 (2)C7—C81.491 (3)
O2—C41.240 (2)C8—H8A0.9800
N1—C61.349 (2)C8—H8B0.9800
N1—N21.394 (2)C8—H8C0.9800
N1—C91.428 (2)C9—C101.391 (3)
N2—C71.326 (2)C9—C141.396 (3)
C1—C21.489 (3)C10—C111.396 (3)
C1—H1A0.9800C10—H100.9500
C1—H1B0.9800C11—C121.390 (3)
C1—H1C0.9800C11—H110.9500
C2—C31.336 (3)C12—C131.378 (3)
C3—C41.460 (3)C12—H120.9500
C3—H30.9500C13—C141.384 (2)
C4—C51.447 (3)C13—H130.9500
C5—C61.380 (3)C14—H140.9500
C6—O1—C2114.47 (15)N2—C7—C8120.75 (18)
C6—N1—N2109.07 (14)C5—C7—C8128.11 (17)
C6—N1—C9132.12 (16)C7—C8—H8A109.5
N2—N1—C9118.81 (14)C7—C8—H8B109.5
C7—N2—N1106.27 (15)H8A—C8—H8B109.5
C2—C1—H1A109.5C7—C8—H8C109.5
C2—C1—H1B109.5H8A—C8—H8C109.5
H1A—C1—H1B109.5H8B—C8—H8C109.5
C2—C1—H1C109.5C10—C9—C14120.13 (17)
H1A—C1—H1C109.5C10—C9—N1122.27 (16)
H1B—C1—H1C109.5C14—C9—N1117.61 (17)
C3—C2—O1122.72 (18)C9—C10—C11119.17 (18)
C3—C2—C1126.60 (18)C9—C10—H10120.4
O1—C2—C1110.67 (17)C11—C10—H10120.4
C2—C3—C4124.29 (18)C12—C11—C10120.53 (19)
C2—C3—H3117.9C12—C11—H11119.7
C4—C3—H3117.9C10—C11—H11119.7
O2—C4—C5124.75 (19)C13—C12—C11119.72 (18)
O2—C4—C3123.43 (18)C13—C12—H12120.1
C5—C4—C3111.82 (17)C11—C12—H12120.1
C6—C5—C7104.07 (16)C12—C13—C14120.65 (18)
C6—C5—C4119.77 (18)C12—C13—H13119.7
C7—C5—C4136.14 (18)C14—C13—H13119.7
N1—C6—O1123.63 (16)C13—C14—C9119.81 (18)
N1—C6—C5109.45 (17)C13—C14—H14120.1
O1—C6—C5126.92 (17)C9—C14—H14120.1
N2—C7—C5111.14 (17)
C6—N1—N2—C70.21 (19)C7—C5—C6—O1179.70 (17)
C9—N1—N2—C7179.19 (15)C4—C5—C6—O11.3 (3)
C6—O1—C2—C30.3 (3)N1—N2—C7—C50.2 (2)
C6—O1—C2—C1178.93 (15)N1—N2—C7—C8178.94 (17)
O1—C2—C3—C40.7 (3)C6—C5—C7—N20.2 (2)
C1—C2—C3—C4178.48 (18)C4—C5—C7—N2178.2 (2)
C2—C3—C4—O2179.56 (19)C6—C5—C7—C8178.93 (19)
C2—C3—C4—C51.1 (3)C4—C5—C7—C80.9 (4)
O2—C4—C5—C6179.34 (18)C6—N1—C9—C103.8 (3)
C3—C4—C5—C61.4 (2)N2—N1—C9—C10176.97 (16)
O2—C4—C5—C71.6 (4)C6—N1—C9—C14176.32 (19)
C3—C4—C5—C7179.1 (2)N2—N1—C9—C142.9 (2)
N2—N1—C6—O1179.85 (15)C14—C9—C10—C110.7 (3)
C9—N1—C6—O10.6 (3)N1—C9—C10—C11179.21 (16)
N2—N1—C6—C50.1 (2)C9—C10—C11—C120.1 (3)
C9—N1—C6—C5179.18 (17)C10—C11—C12—C130.4 (3)
C2—O1—C6—N1179.01 (16)C11—C12—C13—C140.2 (3)
C2—O1—C6—C50.7 (3)C12—C13—C14—C90.4 (3)
C7—C5—C6—N10.0 (2)C10—C9—C14—C130.8 (3)
C4—C5—C6—N1178.43 (16)N1—C9—C14—C13179.05 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C10—H10···O10.952.332.970 (2)124
C14—H14···N20.952.392.748 (2)102
C3—H3···O2i0.952.473.400 (3)167
C8—H8C···O2ii0.982.543.472 (3)158
Symmetry codes: (i) x+1, y, z; (ii) x+2, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H12N2O2
Mr240.26
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)6.7200 (6), 8.2201 (8), 11.2616 (7)
α, β, γ (°)93.914 (6), 95.162 (6), 108.721 (8)
V3)583.66 (9)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.40 × 0.30 × 0.20
Data collection
DiffractometerAgilent SuperNova Dual
diffractometer with an Atlas detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2011)
Tmin, Tmax0.964, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
4356, 2676, 1946
Rint0.031
(sin θ/λ)max1)0.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.056, 0.158, 1.05
No. of reflections2676
No. of parameters165
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.38

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···AD—HH···AD···AD—H···A
C10—H10···O10.952.332.970 (2)124
C14—H14···N20.952.392.748 (2)102
C3—H3···O2i0.952.473.400 (3)167
C8—H8C···O2ii0.982.543.472 (3)158
Symmetry codes: (i) x+1, y, z; (ii) x+2, y+1, z.
 

Footnotes

Additional correspondence author, e-mail: aasiri2@kau.edu.sa.

Acknowledgements

The authors are grateful to the Center of Excellence for Advanced Materials Research and the Chemistry Department at King Abdulaziz University for providing the research facilities. The authors also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (grant No. UM.C/HIR/MOHE/SC/12).

References

First citationAgilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.
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