organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

3-(3-Bromo­benz­yl)isoquinolin-1(2H)-one

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bInstitut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, 38023 Braunschweig, Germany
*Correspondence e-mail: nhrama@qau.edu.pk

(Received 17 November 2009; accepted 26 November 2009; online 4 December 2009)

In the title compound, C16H12BrNO, the ring systems subtend an inter­planar dihedral angle of 75.95 (3)°. In the crystal packing, mol­ecules are linked to form centrosymmetric pairs by pairs of classical N—H⋯O hydrogen bonds.

Related literature

For the biological and pharmaceutical properties of isoquinolin-1(2H)-one derivatives, see: Chern & Li (2004[Chern, M. S. & Li, W. R. (2004). Tetrahedron Lett. 45, 8323-8326.]); Coelho et al. (2003[Coelho, F., Veronese, D., Lopes, E. C. S. & Rossi, R. C. (2003). Tetrahedron Lett. 44, 5731-5735.]); Jayaraman et al. (2000[Jayaraman, M., Fox, B. M., Hollingshead, M., Kohlhagen, G., Pommier, Y. & Cushman, M. (2000). J. Med. Chem. 43, 3688-3698.]); Thompson & Kallmerten (1990[Thompson, R. C. & Kallmerten, J. (1990). J. Org. Chem. 55, 6076-6078.]); Ukita et al. (2001[Ukita, T., Nakamura, Y., Kubo, A., Yamamoto, Y., Moritani, Y., Saruta, K., Higashijoma, T., Kotera, J., Takagi, M., Kikkawa, K. & Omori, K. (2001). J. Med. Chem. 44, 2204-2218.]). For the structure of a related isochromene derivative, see: Ali et al. (2009[Ali, F. I., Babar, T. M., Rama, N. H. & Jones, P. G. (2009). Acta Cryst. E65, o2511.]).

[Scheme 1]

Experimental

Crystal data
  • C16H12BrNO

  • Mr = 314.18

  • Triclinic, [P \overline 1]

  • a = 4.5858 (4) Å

  • b = 9.4976 (7) Å

  • c = 14.8296 (11) Å

  • α = 88.698 (6)°

  • β = 83.829 (6)°

  • γ = 86.529 (6)°

  • V = 640.88 (9) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 4.28 mm−1

  • T = 100 K

  • 0.16 × 0.07 × 0.07 mm

Data collection
  • Oxford Diffraction Nova A diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.817, Tmax = 1.000

  • 9267 measured reflections

  • 2642 independent reflections

  • 2586 reflections with I > 2σ(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.026

  • wR(F2) = 0.068

  • S = 0.90

  • 2642 reflections

  • 176 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.54 e Å−3

  • Δρmin = −0.65 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N—H01⋯Oi 0.85 (3) 1.96 (3) 2.8036 (19) 176 (2)
Symmetry code: (i) -x, -y+1, -z+1.

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); data reduction: CrysAlis RED; 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: XP (Siemens, 1994[Siemens (1994). XP. Siemens Analytical X-ray Instruments, Madison, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Isoquinolin-1(2H)-one derivatives are an important class of heterocyclic compounds with substantial biological activities (Jayaraman et al., 2000) that can be found in naturally occurring products of medicinal interest (Ukita et al., 2001) and synthetic pharmaceuticals such as thalifoline (Chern & Li, 2004), pancratistain and lycoricidine (Thompson & Kallmerten, 1990). In addition, isoquinolin-1(2H)-ones are versatile building blocks for the total synthesis of natural isocarbostyril alkaloids (Coelho et al., 2003). Bearing in mind the pharmaceutical importance of this class of compounds, the title compound, an isoquinolinone derivative containing a 3-bromobenzyl substituent, has been synthesized and its crystal structure is reported here. We have also determined the structure of the analogous isochromene derivative with an oxygen atom replacing the NH group (Ali et al., 2009).

The molecule of the title compound is shown in Fig. 1. Bond lengths and angles may be regarded as normal. The atom sequence N—C2—C10—C11 displays a trans geometry, with a torsion angle of -178.69 (14). The two planar ring systems (including all non-hydrogen substituents) are both planar to within r.m.s. deviations of 0.01 Å and subtend an interplanar angle of 75.95 (3)°. As in the analogous isochromene derivative (Ali et al., 2009), several bond angles depart substantially from ideal values, e.g. C1—N—C2 125.36 (14), N—C2—C10 113.15 (14), C2—C2—C10 126.87 (15), C2—C10—C11 114.88 (14)°.

The packing diagram (Fig. 2) shows the molecules to be linked by classical hydrogen bonds N—H···OC across inversion centres.

Related literature top

For the biological and pharmaceutical properties of isoquinolin-1(2H)-one derivatives, see: Chern & Li (2004); Coelho et al. (2003); Jayaraman et al. (2000); Thompson & Kallmerten (1990); Ukita et al. (2001). For the structure of a related isochromene derivative, see: Ali et al. (2009).

Experimental top

3-(3'-Bromobenzyl)isocoumarin (1 g, 0.0032 mol) in 2-ethoxyethanol was saturated with ammonia gas for 2 h, forming a pale yellow solution that was refluxed for 2 h. The solvent was evaporated under reduced pressure, yielding a fluffy solid. This that was purified by column chromatography using 50% ethyl acetate/petroleum ether as an eluent to afford the title compound (yield 61%; m.p. 228–230 °C). Crystals suitable for X-ray analysis were obtained by slow evaporation of an ethyl acetate solution.

Refinement top

The H atom bount to the nitrogen atom was refined freely. Other H atoms were placed in calculated positions and refined using a riding model with C—H = 0.95–0.99 Å and with Uiso(H) = 1.2 Ueq(C).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Siemens, 1994); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing the atom labelling scheme and displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram viewed parallel to the x axis. Hydrogen bonds are indicated by dashed lines.
[Figure 3] Fig. 3. The formation of the title compound.
3-(3-Bromobenzyl)isoquinolin-1(2H)-one top
Crystal data top
C16H12BrNOZ = 2
Mr = 314.18F(000) = 316
Triclinic, P1Dx = 1.628 Mg m3
Hall symbol: -P 1Cu Kα radiation, λ = 1.54184 Å
a = 4.5858 (4) ÅCell parameters from 9315 reflections
b = 9.4976 (7) Åθ = 3.0–75.6°
c = 14.8296 (11) ŵ = 4.28 mm1
α = 88.698 (6)°T = 100 K
β = 83.829 (6)°Prism, colourless
γ = 86.529 (6)°0.16 × 0.07 × 0.07 mm
V = 640.88 (9) Å3
Data collection top
Oxford Diffraction Nova A
diffractometer
2642 independent reflections
Radiation source: Nova (Cu) X-ray Source2586 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.021
Detector resolution: 10.3543 pixels mm-1θmax = 75.8°, θmin = 3.0°
ω scanh = 55
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
k = 1111
Tmin = 0.817, Tmax = 1.000l = 1818
9267 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)] = 0.026Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.068H atoms treated by a mixture of independent and constrained refinement
S = 0.90 w = 1/[σ2(Fo2) + (0.0429P)2 + 0.8338P]
where P = (Fo2 + 2Fc2)/3
2642 reflections(Δ/σ)max = 0.016
176 parametersΔρmax = 0.54 e Å3
0 restraintsΔρmin = 0.65 e Å3
Crystal data top
C16H12BrNOγ = 86.529 (6)°
Mr = 314.18V = 640.88 (9) Å3
Triclinic, P1Z = 2
a = 4.5858 (4) ÅCu Kα radiation
b = 9.4976 (7) ŵ = 4.28 mm1
c = 14.8296 (11) ÅT = 100 K
α = 88.698 (6)°0.16 × 0.07 × 0.07 mm
β = 83.829 (6)°
Data collection top
Oxford Diffraction Nova A
diffractometer
2642 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
2586 reflections with I > 2σ(I)
Tmin = 0.817, Tmax = 1.000Rint = 0.021
9267 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0260 restraints
wR(F2) = 0.068H atoms treated by a mixture of independent and constrained refinement
S = 0.90Δρmax = 0.54 e Å3
2642 reflectionsΔρmin = 0.65 e Å3
176 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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 3.3521 (0.0017) x + 6.0480 (0.0040) y - 1.1834 (0.0042) z = 2.8164 (0.0038)

* 0.0154 (0.0011) C10 * -0.0101 (0.0014) C11 * -0.0109 (0.0014) C12 * -0.0098 (0.0015) C13 * 0.0036 (0.0015) C14 * 0.0074 (0.0013) C15 * -0.0053 (0.0014) C16 * 0.0097 (0.0008) Br

Rms deviation of fitted atoms = 0.0096

3.3793 (0.0010) x + 4.6226 (0.0023) y + 8.8098 (0.0043) z = 6.7949 (0.0012)

Angle to previous plane (with approximate e.s.d.) = 75.95 (0.03)

* 0.0161 (0.0013) C10 * -0.0154 (0.0013) N * 0.0007 (0.0011) O * -0.0018 (0.0014) C1 * -0.0080 (0.0015) C2 * -0.0054 (0.0015) C3 * 0.0009 (0.0015) C4 * -0.0003 (0.0014) C5 * -0.0016 (0.0014) C6 * -0.0046 (0.0015) C7 * 0.0104 (0.0015) C8 * 0.0089 (0.0015) C9

Rms deviation of fitted atoms = 0.0082

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
Br0.41731 (5)0.68583 (2)0.065128 (12)0.03136 (9)
N0.2730 (3)0.49455 (15)0.40535 (10)0.0155 (3)
H010.131 (5)0.545 (3)0.4306 (17)0.025 (6)*
O0.2033 (3)0.33201 (12)0.51915 (8)0.0187 (2)
C10.3423 (4)0.36850 (17)0.44644 (11)0.0159 (3)
C20.4140 (4)0.54534 (17)0.32544 (11)0.0155 (3)
C30.6381 (4)0.46744 (18)0.28064 (11)0.0168 (3)
H30.73470.50180.22530.020*
C40.7296 (4)0.33229 (17)0.31716 (11)0.0162 (3)
C50.9617 (4)0.24635 (19)0.27310 (12)0.0194 (3)
H51.06300.27780.21780.023*
C61.0421 (4)0.11699 (19)0.30999 (12)0.0216 (4)
H61.19880.06030.27980.026*
C70.8955 (4)0.06803 (18)0.39159 (12)0.0216 (4)
H70.95090.02170.41600.026*
C80.6701 (4)0.15123 (18)0.43607 (12)0.0190 (3)
H80.57210.11920.49180.023*
C90.5853 (4)0.28290 (17)0.39932 (11)0.0159 (3)
C100.2940 (4)0.68958 (18)0.29851 (12)0.0194 (3)
H10A0.31690.75600.34740.023*
H10B0.08110.68530.29370.023*
C110.4378 (4)0.74776 (17)0.21028 (12)0.0170 (3)
C120.3752 (4)0.69677 (18)0.12761 (12)0.0201 (3)
H120.24380.62350.12610.024*
C130.5061 (4)0.75386 (19)0.04767 (12)0.0211 (3)
C140.6969 (4)0.8617 (2)0.04693 (13)0.0237 (4)
H140.78360.90000.00860.028*
C150.7580 (4)0.91238 (19)0.12966 (14)0.0247 (4)
H150.88780.98640.13090.030*
C160.6308 (4)0.85559 (18)0.21038 (12)0.0195 (3)
H160.67580.89060.26650.023*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br0.04174 (14)0.03719 (14)0.01477 (12)0.00054 (9)0.00234 (8)0.00284 (8)
N0.0173 (7)0.0153 (6)0.0130 (6)0.0004 (5)0.0017 (5)0.0002 (5)
O0.0218 (6)0.0182 (6)0.0152 (6)0.0004 (4)0.0016 (5)0.0024 (4)
C10.0177 (8)0.0156 (7)0.0148 (8)0.0021 (6)0.0031 (6)0.0007 (6)
C20.0184 (8)0.0156 (7)0.0130 (7)0.0029 (6)0.0020 (6)0.0008 (6)
C30.0186 (8)0.0182 (8)0.0134 (8)0.0027 (6)0.0002 (6)0.0001 (6)
C40.0166 (7)0.0173 (8)0.0152 (8)0.0021 (6)0.0031 (6)0.0027 (6)
C50.0186 (8)0.0226 (8)0.0168 (8)0.0003 (6)0.0013 (6)0.0030 (6)
C60.0211 (8)0.0228 (8)0.0212 (9)0.0041 (7)0.0050 (7)0.0066 (7)
C70.0270 (9)0.0175 (8)0.0211 (9)0.0031 (7)0.0083 (7)0.0022 (6)
C80.0231 (8)0.0175 (8)0.0170 (8)0.0015 (6)0.0042 (6)0.0003 (6)
C90.0172 (8)0.0158 (7)0.0151 (8)0.0013 (6)0.0036 (6)0.0014 (6)
C100.0243 (8)0.0172 (8)0.0156 (8)0.0019 (6)0.0015 (7)0.0007 (6)
C110.0193 (8)0.0136 (7)0.0166 (8)0.0037 (6)0.0013 (6)0.0014 (6)
C120.0229 (8)0.0175 (8)0.0193 (8)0.0007 (6)0.0004 (7)0.0001 (6)
C130.0250 (9)0.0220 (8)0.0151 (8)0.0051 (7)0.0005 (7)0.0001 (6)
C140.0246 (9)0.0243 (9)0.0202 (9)0.0016 (7)0.0045 (7)0.0073 (7)
C150.0250 (9)0.0205 (8)0.0280 (10)0.0043 (7)0.0009 (7)0.0044 (7)
C160.0213 (8)0.0179 (8)0.0189 (8)0.0012 (6)0.0016 (6)0.0003 (6)
Geometric parameters (Å, º) top
Br—C131.8997 (18)C12—C131.384 (2)
N—C11.367 (2)C13—C141.386 (3)
N—C21.379 (2)C14—C151.390 (3)
O—C11.245 (2)C15—C161.387 (3)
C1—C91.463 (2)N—H010.85 (3)
C2—C31.352 (2)C3—H30.9500
C2—C101.507 (2)C5—H50.9500
C3—C41.438 (2)C6—H60.9500
C4—C91.407 (2)C7—H70.9500
C4—C51.413 (2)C8—H80.9500
C5—C61.379 (3)C10—H10A0.9900
C6—C71.404 (3)C10—H10B0.9900
C7—C81.380 (3)C12—H120.9500
C8—C91.403 (2)C14—H140.9500
C10—C111.509 (2)C15—H150.9500
C11—C161.394 (2)C16—H160.9500
C11—C121.393 (2)
C1—N—C2125.36 (14)C14—C15—C16120.44 (17)
O—C1—N120.74 (15)C15—C16—C11120.83 (17)
O—C1—C9123.72 (15)C1—N—H01117.5 (16)
N—C1—C9115.54 (15)C2—N—H01117.1 (16)
C3—C2—N119.97 (15)C2—C3—H3120.2
C3—C2—C10126.87 (15)C4—C3—H3120.2
N—C2—C10113.15 (14)C6—C5—H5119.8
C2—C3—C4119.66 (15)C4—C5—H5119.8
C9—C4—C5118.38 (15)C5—C6—H6119.6
C9—C4—C3119.57 (15)C7—C6—H6119.6
C5—C4—C3122.06 (15)C8—C7—H7120.2
C6—C5—C4120.36 (16)C6—C7—H7120.2
C5—C6—C7120.90 (16)C7—C8—H8119.9
C8—C7—C6119.53 (16)C9—C8—H8119.9
C7—C8—C9120.25 (17)C2—C10—H10A108.5
C8—C9—C4120.57 (16)C11—C10—H10A108.5
C8—C9—C1119.53 (15)C2—C10—H10B108.5
C4—C9—C1119.89 (15)C11—C10—H10B108.5
C2—C10—C11114.88 (14)H10A—C10—H10B107.5
C16—C11—C12119.00 (16)C13—C12—H12120.3
C16—C11—C10120.36 (16)C11—C12—H12120.3
C12—C11—C10120.63 (15)C13—C14—H14120.9
C13—C12—C11119.41 (16)C15—C14—H14120.9
C12—C13—C14122.10 (17)C16—C15—H15119.8
C12—C13—Br119.42 (14)C14—C15—H15119.8
C14—C13—Br118.46 (13)C15—C16—H16119.6
C13—C14—C15118.22 (16)C11—C16—H16119.6
C2—N—C1—O179.43 (15)O—C1—C9—C80.6 (3)
C2—N—C1—C90.6 (2)N—C1—C9—C8179.41 (15)
C1—N—C2—C31.0 (3)O—C1—C9—C4179.80 (15)
C1—N—C2—C10178.22 (15)N—C1—C9—C40.2 (2)
N—C2—C3—C40.5 (2)C3—C2—C10—C112.2 (3)
C10—C2—C3—C4178.55 (16)N—C2—C10—C11178.69 (14)
C2—C3—C4—C90.2 (2)C2—C10—C11—C16106.28 (18)
C2—C3—C4—C5179.80 (16)C2—C10—C11—C1275.1 (2)
C9—C4—C5—C60.4 (2)C16—C11—C12—C130.1 (2)
C3—C4—C5—C6179.64 (16)C10—C11—C12—C13178.82 (15)
C4—C5—C6—C70.1 (3)C11—C12—C13—C140.6 (3)
C5—C6—C7—C80.8 (3)C11—C12—C13—Br179.29 (12)
C6—C7—C8—C90.9 (3)C12—C13—C14—C150.4 (3)
C7—C8—C9—C40.4 (3)Br—C13—C14—C15179.16 (13)
C7—C8—C9—C1178.80 (15)C13—C14—C15—C160.1 (3)
C5—C4—C9—C80.2 (2)C14—C15—C16—C110.6 (3)
C3—C4—C9—C8179.78 (15)C12—C11—C16—C150.4 (3)
C5—C4—C9—C1179.46 (15)C10—C11—C16—C15178.27 (16)
C3—C4—C9—C10.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H01···Oi0.85 (3)1.96 (3)2.8036 (19)176 (2)
Symmetry code: (i) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC16H12BrNO
Mr314.18
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)4.5858 (4), 9.4976 (7), 14.8296 (11)
α, β, γ (°)88.698 (6), 83.829 (6), 86.529 (6)
V3)640.88 (9)
Z2
Radiation typeCu Kα
µ (mm1)4.28
Crystal size (mm)0.16 × 0.07 × 0.07
Data collection
DiffractometerOxford Diffraction Nova A
diffractometer
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Tmin, Tmax0.817, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
9267, 2642, 2586
Rint0.021
(sin θ/λ)max1)0.629
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.026, 0.068, 0.90
No. of reflections2642
No. of parameters176
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.54, 0.65

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Siemens, 1994).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N—H01···Oi0.85 (3)1.96 (3)2.8036 (19)176 (2)
Symmetry code: (i) x, y+1, z+1.
 

Acknowledgements

TMB is grateful to the Higher Education Commission of Pakistan for financial support for a PhD program.

References

First citationAli, F. I., Babar, T. M., Rama, N. H. & Jones, P. G. (2009). Acta Cryst. E65, o2511.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationChern, M. S. & Li, W. R. (2004). Tetrahedron Lett. 45, 8323–8326.  Web of Science CrossRef CAS Google Scholar
First citationCoelho, F., Veronese, D., Lopes, E. C. S. & Rossi, R. C. (2003). Tetrahedron Lett. 44, 5731–5735.  Web of Science CrossRef CAS Google Scholar
First citationJayaraman, M., Fox, B. M., Hollingshead, M., Kohlhagen, G., Pommier, Y. & Cushman, M. (2000). J. Med. Chem. 43, 3688–3698.  Web of Science PubMed Google Scholar
First citationOxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSiemens (1994). XP. Siemens Analytical X-ray Instruments, Madison, USA.  Google Scholar
First citationThompson, R. C. & Kallmerten, J. (1990). J. Org. Chem. 55, 6076–6078.  CrossRef CAS Web of Science Google Scholar
First citationUkita, T., Nakamura, Y., Kubo, A., Yamamoto, Y., Moritani, Y., Saruta, K., Higashijoma, T., Kotera, J., Takagi, M., Kikkawa, K. & Omori, K. (2001). J. Med. Chem. 44, 2204–2218.  Web of Science CrossRef PubMed CAS Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds