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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

2-Carb­oxy­anilinium chloride monohydrate

aInstitute of Chemistry, University of the Punjab, Lahore 54590, Pakistan, bDepartment of Physics, University of Sargodha, Sagrodha, Pakistan, and cDepartment of Chemistry, F.C. College & University, Lahore, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 6 September 2008; accepted 12 September 2008; online 17 September 2008)

In the mol­ecule of the title compound, C7H8NO2+·Cl·H2O, an intra­molecular N—H⋯O hydrogen bond results in the formation of a non-planar six-membered ring adopting a flattened boat conformation. In the crystal structure, inter­molecular O—H⋯O and N—H⋯Cl hydrogen bonds link the mol­ecules. There is a C=O⋯π contact between the carbonyl unit and the centroid of the benzene ring. There is a C=O⋯π contact [C⋯Cg = 3.5802 (18), C—O⋯Cg = 89 (1)°] between the carbonyl unit and the centroid of the benzene ring.

Related literature

For applications of anthranilic acid derivatives, see: Congiu et al. (2005[Congiu, C., Cocco, M. T., Lilliu, V. & Onnis, V. (2005). J. Med. Chem. 48, 8245-8252.]); Nittoli et al. (2005[Nittoli, T., Curran, K., Insaf, S., DiGrandi, M., Orlowski, M., Chopra, R., Agarwal, A., Howe, A. Y. M., Prashad, A., Floyd, M. B., Johnson, B., Sutherland, A., Wheless, K., Feld, B., O'Connell, J., Mansour, T. S. & Bloom, J. (2005). J. Med. Chem. 48, 7560-7581.]). For a related structure, see: Bahadur et al. (2007[Bahadur, S. A., Kannan, R. S. & Sridhar, B. (2007). Acta Cryst. E63, o2722-o2723.]); For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For ring puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C7H8NO2+·Cl·H2O

  • Mr = 191.61

  • Monoclinic, C 2/c

  • a = 23.094 (4) Å

  • b = 4.7833 (8) Å

  • c = 16.381 (3) Å

  • β = 91.605 (9)°

  • V = 1808.8 (5) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.39 mm−1

  • T = 296 (2) K

  • 0.28 × 0.10 × 0.06 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]) Tmin = 0.975, Tmax = 0.985

  • 9747 measured reflections

  • 2238 independent reflections

  • 1749 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.101

  • S = 1.05

  • 2238 reflections

  • 139 parameters

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

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯O3i 0.82 (2) 1.73 (2) 2.539 (2) 171 (2)
N1—H1A⋯O2 0.91 (2) 1.91 (2) 2.6820 (19) 142.1 (18)
N1—H1B⋯Cl1ii 0.88 (2) 2.28 (2) 3.1464 (16) 166.6 (18)
N1—H1C⋯Cl1iii 0.958 (19) 2.181 (19) 3.1231 (16) 167.5 (18)
O3—H3A⋯Cl1 0.76 (3) 2.42 (3) 3.1452 (18) 160 (3)
O3—H3B⋯O2iv 0.78 (3) 2.04 (3) 2.777 (3) 159 (3)
Symmetry codes: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x, y, -z+{\script{1\over 2}}]; (iii) [x, -y+1, z+{\script{1\over 2}}]; (iv) [x, -y+2, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

Anthranilic acid is widely used for various purposes such as production of dyes, pigments and saccharin. Its derivatives also have importance in medicinal chemistry and are used as antiinflammatory and anticancer agents (Congiu et al., 2005) and for inhibition of Hepatitis C NS5B polymerase (Nittoli et al., 2005). The title compound has been prepared to see its bioactivity with hope that it will be a good antibactarial agent at the economical cost and to utilize for preparing further derivatives. Crystal structures of proton transfer compound of 2-aminobenzoic acid with nitric acid (Bahadur et al., 2007) has been reported, where the intramolecular N-H···O hydrogen bond has also been observed.

In the molecule of the title compound (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Ring A (C2-C7) is, of course, planar. The intramolecular N-H···O hydrogen bond (Table 1) results in the formation of a nonplanar six-membered ring B (N1/O2/C1/C2/C7/H1A) having total puckering amplitude, QT, of 0.127 (3) Å, and flattened boat conformation [ϕ = -21.25 (3)°, θ = 44.41 (3)°] (Cremer & Pople, 1975).

In the crystal structure, intermolecular O-H···O and N-H···Cl hydrogen bonds (Table 1) link the molecules (Fig. 2), in which they may be effective in the stabilization of the structure. The C=O···π contact (Table 1) between the carbonyl moiety and the centroid of the benzene ring may further stabilize the structure.

Related literature top

For applications of anthranilic acid derivatives, see: Congiu et al. (2005); Nittoli et al. (2005). For a related structure, see:

Bahadur et al. (2007); For bond-length data, see: Allen et al. (1987). For ring puckering parameters, see: Cremer & Pople (1975). Cg is the centroid of the benzene ring.

Experimental top

For the preparation of the title compound, 2-aminobenzoic acid (4.11 g, 3 mmol) and trichloroacetic acid (1.64 g, 1 mmol) were neutrilized with Na2CO3 separately in H2O, and then mixed together. Na2CO3 (3.18 g) was added to the resulting mixture and refluxed for 4 h. The refluxed solution was cooled, and concenterated HCl was added to get PH = 1. The solution was kept in open air for 3 d to get the suitable crystals.

Refinement top

H atoms were located in difference syntheses and refined as [O-H = 0.82 (2) Å (for OH); O-H = 0.76 (3) and 0.78 (3) Å (for H2O); N-H = 0.88 (2)-0.958 (19) Å, ( for NH3) and C-H = 0.93 (2)-0.96 (2) Å (for CH)] and constrained to ride on their parent atoms with Uiso(H) = xUeq(C,N,O), where x = 1.5 for NH3 H and x = 1.2 for all other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999) and PLATON..

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are shown as dashed lines.
[Figure 2] Fig. 2. A packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.
2-Carboxyanilinium chloride monohydrate top
Crystal data top
C7H8NO2+·Cl·H2OF(000) = 800
Mr = 191.61Dx = 1.407 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 2238 reflections
a = 23.094 (4) Åθ = 2.5–28.3°
b = 4.7833 (8) ŵ = 0.39 mm1
c = 16.381 (3) ÅT = 296 K
β = 91.605 (9)°Prism, brown
V = 1808.8 (5) Å30.28 × 0.10 × 0.06 mm
Z = 8
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2238 independent reflections
Radiation source: fine-focus sealed tube1749 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
Detector resolution: 7.5 pixels mm-1θmax = 28.3°, θmin = 2.5°
ω scansh = 3030
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 63
Tmin = 0.975, Tmax = 0.985l = 2120
9747 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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0476P)2 + 1.0872P]
where P = (Fo2 + 2Fc2)/3
2238 reflections(Δ/σ)max < 0.001
139 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C7H8NO2+·Cl·H2OV = 1808.8 (5) Å3
Mr = 191.61Z = 8
Monoclinic, C2/cMo Kα radiation
a = 23.094 (4) ŵ = 0.39 mm1
b = 4.7833 (8) ÅT = 296 K
c = 16.381 (3) Å0.28 × 0.10 × 0.06 mm
β = 91.605 (9)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2238 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1749 reflections with I > 2σ(I)
Tmin = 0.975, Tmax = 0.985Rint = 0.025
9747 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.101H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.30 e Å3
2238 reflectionsΔρmin = 0.22 e Å3
139 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
Cl10.05634 (2)0.81018 (10)0.08328 (3)0.0425 (2)
O10.24332 (5)0.7928 (3)0.36801 (9)0.0551 (5)
O20.17708 (5)0.9236 (3)0.45555 (8)0.0493 (4)
O30.18909 (7)0.6690 (4)0.07558 (14)0.0796 (7)
N10.07438 (6)0.6617 (3)0.45470 (9)0.0340 (4)
C10.19199 (7)0.7781 (3)0.39900 (10)0.0338 (5)
C20.15328 (6)0.5699 (3)0.35784 (9)0.0304 (4)
C30.17259 (8)0.4219 (4)0.29012 (10)0.0408 (5)
C40.13710 (9)0.2318 (4)0.25017 (11)0.0462 (6)
C50.08157 (8)0.1841 (4)0.27706 (12)0.0466 (6)
C60.06160 (7)0.3269 (4)0.34388 (11)0.0398 (5)
C70.09727 (6)0.5188 (3)0.38354 (9)0.0300 (4)
H10.2619 (10)0.922 (5)0.3885 (14)0.0661*
H1A0.0991 (9)0.802 (4)0.4684 (12)0.0510*
H1B0.0399 (10)0.732 (4)0.4423 (13)0.0510*
H1C0.0724 (9)0.534 (4)0.4996 (12)0.0510*
H30.2113 (9)0.452 (4)0.2717 (11)0.0489*
H3A0.1584 (14)0.692 (7)0.0892 (19)0.0955*
H3B0.1945 (14)0.777 (6)0.041 (2)0.0955*
H40.1511 (9)0.133 (5)0.2061 (13)0.0554*
H50.0582 (9)0.052 (4)0.2493 (12)0.0558*
H60.0245 (9)0.298 (4)0.3628 (12)0.0477*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0314 (2)0.0499 (3)0.0463 (3)0.0004 (2)0.0035 (2)0.0055 (2)
O10.0320 (7)0.0668 (9)0.0673 (9)0.0189 (6)0.0174 (6)0.0255 (7)
O20.0401 (7)0.0554 (8)0.0531 (7)0.0144 (6)0.0133 (6)0.0206 (6)
O30.0408 (8)0.0837 (13)0.1153 (15)0.0249 (8)0.0207 (9)0.0514 (11)
N10.0255 (7)0.0362 (8)0.0406 (8)0.0012 (6)0.0081 (5)0.0030 (6)
C10.0283 (8)0.0362 (8)0.0372 (8)0.0030 (6)0.0049 (6)0.0006 (7)
C20.0279 (7)0.0312 (8)0.0323 (7)0.0017 (6)0.0041 (6)0.0009 (6)
C30.0357 (9)0.0456 (10)0.0416 (9)0.0040 (8)0.0111 (7)0.0063 (8)
C40.0512 (11)0.0487 (10)0.0391 (9)0.0031 (8)0.0077 (8)0.0135 (8)
C50.0445 (10)0.0462 (10)0.0486 (10)0.0088 (8)0.0048 (8)0.0109 (8)
C60.0292 (8)0.0435 (10)0.0466 (9)0.0053 (7)0.0018 (7)0.0030 (8)
C70.0278 (7)0.0307 (8)0.0315 (7)0.0005 (6)0.0031 (6)0.0014 (6)
Geometric parameters (Å, º) top
O1—C11.304 (2)C2—C31.399 (2)
O2—C11.216 (2)C2—C71.393 (2)
O1—H10.82 (2)C3—C41.377 (3)
O3—H3B0.78 (3)C4—C51.387 (3)
O3—H3A0.76 (3)C5—C61.380 (3)
N1—C71.463 (2)C6—C71.383 (2)
N1—H1B0.88 (2)C3—H30.96 (2)
N1—H1C0.958 (19)C4—H40.93 (2)
N1—H1A0.91 (2)C5—H50.94 (2)
C1—C21.487 (2)C6—H60.93 (2)
Cl1···O33.1452 (18)N1···O22.6820 (19)
Cl1···N1i3.3227 (16)C1···C3iv3.581 (2)
Cl1···N1ii3.1464 (16)C1···O3vi3.339 (2)
Cl1···N1iii3.1231 (16)C1···C4iv3.477 (3)
Cl1···H5iv2.96 (2)C3···C1x3.581 (2)
Cl1···H3A2.42 (3)C3···O1viii3.338 (2)
Cl1···H6v3.13 (2)C4···C1x3.477 (3)
Cl1···H1Bii2.28 (2)C1···H1A2.46 (2)
Cl1···H1Ai2.84 (2)H1···H3Bvi2.27 (4)
Cl1···H1Ciii2.181 (19)H1···H3Avi2.27 (4)
O1···C3vi3.338 (2)H1···O3vi1.73 (2)
O1···O3vi2.539 (2)H1A···C12.46 (2)
O2···O3vii2.777 (3)H1A···O21.91 (2)
O2···N12.6820 (19)H1A···Cl1vii2.84 (2)
O3···O2i2.777 (3)H1B···Cl1ii2.28 (2)
O3···O1viii2.539 (2)H1B···H62.47 (3)
O3···C1viii3.339 (2)H1C···Cl1ix2.181 (19)
O3···Cl13.1452 (18)H3···O12.372 (19)
O1···H4vi2.86 (2)H3···O1viii2.655 (19)
O1···H3vi2.655 (19)H3A···O2i2.90 (3)
O1···H32.372 (19)H3A···H1viii2.27 (4)
O2···H3Avii2.90 (3)H3A···Cl12.42 (3)
O2···H3Bvii2.04 (3)H3B···H1viii2.27 (4)
O2···H1A1.91 (2)H3B···O2i2.04 (3)
O3···H1viii1.73 (2)H4···O1viii2.86 (2)
N1···Cl1ix3.1231 (16)H5···Cl1x2.96 (2)
N1···Cl1vii3.3227 (16)H6···Cl1xi3.13 (2)
N1···Cl1ii3.1464 (16)H6···H1B2.47 (3)
C1—O1—H1110.7 (16)C3—C4—C5120.07 (17)
H3A—O3—H3B107 (3)C4—C5—C6120.20 (17)
C7—N1—H1C109.9 (12)C5—C6—C7119.54 (15)
H1A—N1—H1B109.5 (18)N1—C7—C2121.21 (13)
H1B—N1—H1C110.9 (19)C2—C7—C6121.35 (14)
C7—N1—H1A107.7 (13)N1—C7—C6117.43 (13)
H1A—N1—H1C109.0 (17)C2—C3—H3119.5 (11)
C7—N1—H1B109.8 (14)C4—C3—H3119.7 (11)
O1—C1—O2123.05 (15)C5—C4—H4120.6 (13)
O1—C1—C2113.64 (14)C3—C4—H4119.3 (13)
O2—C1—C2123.31 (15)C4—C5—H5118.7 (13)
C3—C2—C7118.04 (14)C6—C5—H5121.1 (13)
C1—C2—C7122.14 (13)C5—C6—H6121.5 (12)
C1—C2—C3119.82 (14)C7—C6—H6119.0 (12)
C2—C3—C4120.80 (17)
O1—C1—C2—C32.8 (2)C3—C2—C7—N1178.91 (14)
O1—C1—C2—C7178.32 (14)C3—C2—C7—C60.3 (2)
O2—C1—C2—C3176.32 (16)C2—C3—C4—C50.3 (3)
O2—C1—C2—C72.5 (2)C3—C4—C5—C60.1 (3)
C1—C2—C3—C4178.82 (16)C4—C5—C6—C70.3 (3)
C7—C2—C3—C40.1 (2)C5—C6—C7—N1179.16 (16)
C1—C2—C7—N12.2 (2)C5—C6—C7—C20.5 (3)
C1—C2—C7—C6179.17 (15)
Symmetry codes: (i) x, y+2, z1/2; (ii) x, y, z+1/2; (iii) x, y+1, z1/2; (iv) x, y+1, z; (v) x, y+1, z+1/2; (vi) x+1/2, y+1/2, z+1/2; (vii) x, y+2, z+1/2; (viii) x+1/2, y1/2, z+1/2; (ix) x, y+1, z+1/2; (x) x, y1, z; (xi) x, y1, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O3vi0.82 (2)1.73 (2)2.539 (2)171 (2)
N1—H1A···O20.91 (2)1.91 (2)2.6820 (19)142.1 (18)
N1—H1B···Cl1ii0.88 (2)2.28 (2)3.1464 (16)166.6 (18)
N1—H1C···Cl1ix0.958 (19)2.181 (19)3.1231 (16)167.5 (18)
O3—H3A···Cl10.76 (3)2.42 (3)3.1452 (18)160 (3)
O3—H3B···O2i0.78 (3)2.04 (3)2.777 (3)159 (3)
C1—O2···Cgiv1.22 (1)3.40 (1)3.5802 (18)89 (1)
Symmetry codes: (i) x, y+2, z1/2; (ii) x, y, z+1/2; (iv) x, y+1, z; (vi) x+1/2, y+1/2, z+1/2; (ix) x, y+1, z+1/2.

Experimental details

Crystal data
Chemical formulaC7H8NO2+·Cl·H2O
Mr191.61
Crystal system, space groupMonoclinic, C2/c
Temperature (K)296
a, b, c (Å)23.094 (4), 4.7833 (8), 16.381 (3)
β (°) 91.605 (9)
V3)1808.8 (5)
Z8
Radiation typeMo Kα
µ (mm1)0.39
Crystal size (mm)0.28 × 0.10 × 0.06
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.975, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
9747, 2238, 1749
Rint0.025
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.101, 1.05
No. of reflections2238
No. of parameters139
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.30, 0.22

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX publication routines (Farrugia, 1999) and PLATON..

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O3i0.82 (2)1.73 (2)2.539 (2)171 (2)
N1—H1A···O20.91 (2)1.91 (2)2.6820 (19)142.1 (18)
N1—H1B···Cl1ii0.88 (2)2.28 (2)3.1464 (16)166.6 (18)
N1—H1C···Cl1iii0.958 (19)2.181 (19)3.1231 (16)167.5 (18)
O3—H3A···Cl10.76 (3)2.42 (3)3.1452 (18)160 (3)
O3—H3B···O2iv0.78 (3)2.04 (3)2.777 (3)159 (3)
C1—O2···Cgv1.216 (2)3.3988 (16)3.5802 (18)88.5 (1)
Symmetry codes: (i) x+1/2, y+1/2, z+1/2; (ii) x, y, z+1/2; (iii) x, y+1, z+1/2; (iv) x, y+2, z1/2; (v) x, y+1, z.
 

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore.

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Web of Science Google Scholar
First citationBahadur, S. A., Kannan, R. S. & Sridhar, B. (2007). Acta Cryst. E63, o2722–o2723.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationBruker (2005). SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.  Google Scholar
First citationCongiu, C., Cocco, M. T., Lilliu, V. & Onnis, V. (2005). J. Med. Chem. 48, 8245–8252.  Web of Science CrossRef PubMed CAS Google Scholar
First citationCremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.  CrossRef CAS Web of Science Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
First citationNittoli, T., Curran, K., Insaf, S., DiGrandi, M., Orlowski, M., Chopra, R., Agarwal, A., Howe, A. Y. M., Prashad, A., Floyd, M. B., Johnson, B., Sutherland, A., Wheless, K., Feld, B., O'Connell, J., Mansour, T. S. & Bloom, J. (2005). J. Med. Chem. 48, 7560–7581.  Web of Science PubMed Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2003). J. Appl. Cryst. 36, 7–13.  Web of Science CrossRef CAS IUCr Journals 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