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

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ADDENDA AND ERRATA

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N-(2-Allyl-4-eth­­oxy-2H-indazol-5-yl)-4-methyl­benzene­sulfonamide

aLaboratoire de Chimie Organique et Analytique, Université Sultan Moulay Slimane, Faculté des Sciences et Techniques, Béni-Mellal, BP 523, Morocco, bIST Istituto Nazionale per la Ricerca sul Cancro, U.O.C. Terapia Immunologica, L. go R. Benzi 10, 16132 Genova, Italy, and cLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: l_bouissane@yahoo.fr

(Received 22 April 2014; accepted 24 April 2014; online 30 April 2014)

The indazole ring system of the title compound, C19H21N3O3S, is almost planar (r.m.s. deviation = 0.0192 Å) and forms dihedral angles of 77.99 (15) and 83.9 (3)° with the benzene ring and allyl group, respectively. In the crystal, centrosymmetrically related mol­ecules are connected by pairs of N—H⋯O hydrogen bonds into dimers, which are further linked by C—H⋯O hydrogen bonds, forming columns parallel to the b axis.

Related literature

For the biological activity of sulfonamides, see: Drews (2000[Drews, J. (2000). Science, 287, 1960-1964.]); Supuran & Scozzafava (2001[Supuran, C. T. & Scozzafava, A. (2001). Immun. Endoc. Metab. Agents Med. Chem. 1, 61-97.]); Abbate et al. (2004[Abbate, F., Casini, A., Owa, T., Scozzafava, A. & Supuran, C. T. (2004). Bioorg. Med. Chem. Lett. 14, 217-223.]); Rostom (2006[Rostom, S. A. (2006). Bioorg. Med. Chem. 14, 6475-6485.]); Ghorab et al. (2009[Ghorab, M. M., Ragab, F. A. & Hamed, M. M. (2009). Eur. J. Med. Chem. 44, 4211-4217.]). For similar compounds, see: Bouissane et al. (2006[Bouissane, L., El Kazzouli, S., Leonce, S., Pffeifer, P., Rakib, M. E., Khouili, M. & Guillaumet, G. (2006). Bioorg. Med. Chem. 14, 1078-1088.]); Abbassi et al. (2012[Abbassi, N., Chicha, H., Rakib, E. M., Hannioui, A., Alaoui, M., Hajjaji, A., Geffken, D., Aiello, C., Gangemi, R., Rosano, C. & Viale, M. (2012). Eur. J. Med. Chem. 57, 240-249.], 2013[Abbassi, N., Rakib, E. M., Hannioui, A., Saadi, M. & El Ammari, L. (2013). Acta Cryst. E69, o190-o191.]).

[Scheme 1]

Experimental

Crystal data
  • C19H21N3O3S

  • Mr = 371.45

  • Monoclinic, C 2/c

  • a = 26.0808 (5) Å

  • b = 7.9335 (2) Å

  • c = 21.1573 (4) Å

  • β = 122.839 (1)°

  • V = 3678.13 (14) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.20 mm−1

  • T = 296 K

  • 0.42 × 0.35 × 0.30 mm

Data collection
  • Bruker X8 APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.693, Tmax = 0.747

  • 37135 measured reflections

  • 4059 independent reflections

  • 3100 reflections with I > 2σ(I)

  • Rint = 0.048

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.134

  • S = 1.07

  • 4059 reflections

  • 235 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3N⋯O3i 0.84 2.14 2.960 (2) 164
C17—H17⋯O2ii 0.93 2.54 3.333 (3) 144
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x, y+1, z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Sulfonamides possess many types of biological activities and representatives of this class of pharmacological agents are widely used in clinic as antibacterial, hypoglycemic, diuretic and anti-carbonic anhydrase agents (Drews, 2000; Supuran & Scozzafava, 2001). Previously, a host of structurally novel sulfonamide derivatives have been reported to show substantial antitumor activity in vitro and/or in vivo (Abbate et al., 2004; Rostom, 2006; Ghorab et al., 2009). Recently, some N-[7(6)-indazolyl]arylsulfonamides prepared by our research group showed important antiproliferative activity against some human and murine cell lines ((Abbassi et al., 2012; Abbassi et al., 2013; Bouissane et al., 2006).

The molecule of the title compound is built up from two fused almost coplanar five- and six-membered rings (N1/N2/C4-C10), with a maximum deviation of 0.029 (3) Å for atom C9 (Fig. 1). The indazole ring system is nearly perpendicular to the planes through the allyl group (C1–C3) and benzene ring (C13–C18) as indicated by the dihedral angles between them of 83.9 (3) and 77.99 (15)°, respectively. An intramolecular C—H···O hydrogen bond (Table 1) stabilizes the molecular comformation. The cohesion of the crystal structure is ensured by N3–H3N···O3 hydrogen bonds between centrosymmetrically related molecules forming dimers, which are further connected into columns parallel to the b axis by C17–H17···O2 hydrogen bonds (Fig. 2, Table 1).

Related literature top

For the biological activity of sulfonamides, see: Drews (2000); Supuran & Scozzafava (2001); Abbate et al. (2004); Rostom (2006); Ghorab et al. (2009). For similar compounds, see: Bouissane et al. (2006); Abbassi et al. (2012, 2013).

Experimental top

A mixture of 2-allyl-5-nitroindazole (1.22 mmol) and anhydrous SnCl2 (1.1 g, 6.1 mmol) in 25 ml of absolute ethanol was heated at 60°C for 6 h. After reduction, the starting material disappeared, and the solution was allowed to cool down. The pH was made slightly basic (pH 7–8) by addition of 5% aqueous potassium bicarbonate before extraction with ethyl acetate. The organic phase was washed with brine and dried over magnesium sulfate. The solvent was removed to afford the amine, which was immediately dissolved in pyridine (5 ml) and then reacted with 4-methylbenzenesulfonyl chloride (1.25 mmol) at room temperature for 24 h. The reaction mixture was then concentrated in vacuo and the resulting residue was purified by flash chromatography (eluted with ethyl acetate:hexane 2:8 v/v). The title compound was recrystallized from ethanol (yield = 78%, m. p. = 388 K).

Refinement top

H atoms were located in a difference Fourier map and treated as riding with C–H = 0.93-0.97 Å, N–H = 0.84 Å, and with Uiso(H) = 1.2 Ueq (C, N) or 1.5 Ueq for methyl H atoms. Three outliers (2 0 0, -2 0 2, 1 1 1) were omitted in the last cycles of refinement.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as small circles.
[Figure 2] Fig. 2. Projection of the crystal structure of the title compound along the b axis, showing molecules linked by hydrogen bonds (dashed lines).
N-(2-Allyl-4-ethoxy-2H-indazol-5-yl)-4-methylbenzenesulfonamide top
Crystal data top
C19H21N3O3SF(000) = 1568
Mr = 371.45Dx = 1.342 Mg m3
Monoclinic, C2/cMelting point: 388 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 26.0808 (5) ÅCell parameters from 4059 reflections
b = 7.9335 (2) Åθ = 2.3–27.1°
c = 21.1573 (4) ŵ = 0.20 mm1
β = 122.839 (1)°T = 296 K
V = 3678.13 (14) Å3Block, colourless
Z = 80.42 × 0.35 × 0.30 mm
Data collection top
Bruker X8 APEX
diffractometer
4059 independent reflections
Radiation source: fine-focus sealed tube3100 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
ϕ and ω scansθmax = 27.1°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 3333
Tmin = 0.693, Tmax = 0.747k = 1010
37135 measured reflectionsl = 2727
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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0616P)2 + 3.2227P]
where P = (Fo2 + 2Fc2)/3
4059 reflections(Δ/σ)max < 0.001
235 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.36 e Å3
Crystal data top
C19H21N3O3SV = 3678.13 (14) Å3
Mr = 371.45Z = 8
Monoclinic, C2/cMo Kα radiation
a = 26.0808 (5) ŵ = 0.20 mm1
b = 7.9335 (2) ÅT = 296 K
c = 21.1573 (4) Å0.42 × 0.35 × 0.30 mm
β = 122.839 (1)°
Data collection top
Bruker X8 APEX
diffractometer
4059 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3100 reflections with I > 2σ(I)
Tmin = 0.693, Tmax = 0.747Rint = 0.048
37135 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.134H-atom parameters constrained
S = 1.07Δρmax = 0.28 e Å3
4059 reflectionsΔρmin = 0.36 e Å3
235 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 > 2σ(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
C10.18654 (15)1.1635 (5)0.01834 (19)0.0893 (10)
H1A0.15821.19680.02970.107*
H1B0.20381.24310.00300.107*
C20.20182 (12)1.0079 (4)0.02385 (15)0.0683 (8)
H20.23020.97860.01210.082*
C30.17730 (12)0.8734 (4)0.04754 (16)0.0724 (8)
H3A0.15110.80160.00470.087*
H3B0.15240.92340.06380.087*
C40.26062 (10)0.8146 (3)0.18156 (14)0.0550 (6)
H40.25920.91610.20250.066*
C50.30029 (9)0.6795 (3)0.21932 (12)0.0414 (5)
C60.28267 (10)0.5576 (3)0.16164 (13)0.0483 (5)
C70.31134 (11)0.3998 (3)0.17722 (15)0.0596 (7)
H70.29900.31980.13950.071*
C80.35751 (10)0.3678 (3)0.24888 (13)0.0496 (6)
H90.37620.26250.26060.060*
C90.37814 (9)0.4902 (2)0.30660 (11)0.0356 (4)
C100.35000 (9)0.6438 (3)0.29332 (11)0.0363 (4)
C110.36304 (15)0.9237 (3)0.34341 (16)0.0712 (8)
H11B0.32050.95360.32070.085*
H11A0.37580.96150.31040.085*
C120.40124 (14)1.0063 (4)0.41880 (16)0.0715 (8)
H12B0.39691.12640.41300.107*
H12A0.44330.97610.44090.107*
H12C0.38800.96920.45090.107*
C130.52408 (8)0.5771 (2)0.37746 (10)0.0329 (4)
C140.55443 (10)0.5564 (3)0.34089 (12)0.0428 (5)
H140.55860.45000.32580.051*
C150.57834 (11)0.6960 (3)0.32728 (13)0.0494 (6)
H150.59950.68210.30360.059*
C160.57191 (10)0.8555 (3)0.34757 (13)0.0460 (5)
C170.54115 (11)0.8730 (3)0.38424 (13)0.0477 (5)
H170.53630.97970.39840.057*
C180.51797 (10)0.7357 (3)0.39973 (12)0.0421 (5)
H180.49820.74900.42510.050*
C190.59695 (14)1.0079 (4)0.33072 (18)0.0743 (8)
H19A0.63030.97460.32640.111*
H19B0.61101.08840.37070.111*
H19C0.56541.05790.28430.111*
N10.22511 (9)0.7686 (3)0.10913 (12)0.0592 (6)
N20.23653 (9)0.6139 (3)0.09414 (12)0.0616 (6)
N30.42783 (7)0.4479 (2)0.38105 (9)0.0368 (4)
H3N0.43220.50870.41630.044*
O10.37042 (8)0.7467 (2)0.35341 (9)0.0589 (5)
O20.48852 (7)0.26717 (19)0.34847 (9)0.0493 (4)
O30.53203 (7)0.3684 (2)0.47767 (8)0.0486 (4)
S10.49532 (2)0.39937 (6)0.39815 (3)0.03587 (16)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0645 (19)0.080 (2)0.091 (2)0.0064 (17)0.0212 (18)0.005 (2)
C20.0484 (14)0.096 (2)0.0516 (15)0.0093 (15)0.0215 (12)0.0095 (16)
C30.0416 (13)0.081 (2)0.0604 (17)0.0034 (13)0.0054 (13)0.0161 (15)
C40.0419 (12)0.0544 (15)0.0548 (15)0.0074 (11)0.0172 (11)0.0020 (12)
C50.0333 (10)0.0438 (12)0.0446 (12)0.0008 (9)0.0195 (9)0.0008 (10)
C60.0347 (10)0.0561 (14)0.0435 (12)0.0049 (10)0.0144 (10)0.0076 (11)
C70.0518 (14)0.0542 (15)0.0531 (15)0.0049 (11)0.0156 (12)0.0207 (12)
C80.0480 (12)0.0370 (12)0.0566 (14)0.0018 (9)0.0236 (12)0.0097 (10)
C90.0352 (10)0.0320 (10)0.0392 (11)0.0016 (8)0.0200 (9)0.0006 (9)
C100.0370 (10)0.0355 (11)0.0380 (11)0.0032 (8)0.0213 (9)0.0040 (9)
C110.094 (2)0.0451 (16)0.0664 (18)0.0085 (14)0.0381 (17)0.0006 (13)
C120.085 (2)0.0484 (16)0.080 (2)0.0012 (14)0.0440 (17)0.0163 (14)
C130.0330 (9)0.0321 (10)0.0300 (9)0.0052 (8)0.0147 (8)0.0033 (8)
C140.0478 (12)0.0407 (12)0.0449 (12)0.0063 (9)0.0284 (10)0.0007 (10)
C150.0514 (13)0.0562 (15)0.0532 (13)0.0016 (11)0.0365 (12)0.0031 (11)
C160.0424 (11)0.0458 (13)0.0473 (13)0.0005 (10)0.0227 (10)0.0087 (10)
C170.0558 (13)0.0327 (12)0.0596 (14)0.0042 (10)0.0346 (12)0.0016 (10)
C180.0509 (12)0.0338 (11)0.0524 (13)0.0047 (9)0.0352 (11)0.0014 (10)
C190.0806 (19)0.0632 (19)0.095 (2)0.0091 (15)0.0580 (18)0.0138 (16)
N10.0365 (10)0.0692 (15)0.0498 (12)0.0019 (9)0.0089 (9)0.0063 (11)
N20.0434 (11)0.0702 (15)0.0492 (12)0.0022 (10)0.0109 (10)0.0057 (11)
N30.0419 (9)0.0324 (9)0.0389 (9)0.0019 (7)0.0238 (8)0.0019 (7)
O10.0722 (11)0.0430 (9)0.0508 (10)0.0097 (8)0.0264 (9)0.0026 (8)
O20.0595 (10)0.0317 (8)0.0595 (10)0.0054 (7)0.0341 (8)0.0047 (7)
O30.0523 (9)0.0491 (9)0.0398 (8)0.0167 (7)0.0221 (7)0.0171 (7)
S10.0418 (3)0.0277 (3)0.0375 (3)0.0078 (2)0.0211 (2)0.0056 (2)
Geometric parameters (Å, º) top
C1—C21.284 (4)C11—H11A0.9700
C1—H1A0.9300C12—H12B0.9600
C1—H1B0.9300C12—H12A0.9600
C2—C31.465 (4)C12—H12C0.9600
C2—H20.9300C13—C181.382 (3)
C3—N11.477 (3)C13—C141.384 (3)
C3—H3A0.9700C13—S11.760 (2)
C3—H3B0.9700C14—C151.376 (3)
C4—N11.342 (3)C14—H140.9300
C4—C51.400 (3)C15—C161.375 (3)
C4—H40.9300C15—H150.9300
C5—C101.418 (3)C16—C171.393 (3)
C5—C61.424 (3)C16—C191.506 (3)
C6—N21.350 (3)C17—C181.369 (3)
C6—C71.402 (3)C17—H170.9300
C7—C81.354 (3)C18—H180.9300
C7—H70.9300C19—H19A0.9600
C8—C91.418 (3)C19—H19B0.9600
C8—H90.9300C19—H19C0.9600
C9—C101.370 (3)N1—N21.341 (3)
C9—N31.435 (3)N3—S11.6389 (16)
C10—O11.354 (3)N3—H3N0.8417
C11—O11.418 (3)O2—S11.4261 (15)
C11—C121.497 (4)O3—S11.4357 (15)
C11—H11B0.9700
C2—C1—H1A120.0C11—C12—H12C109.5
C2—C1—H1B120.0H12B—C12—H12C109.5
H1A—C1—H1B120.0H12A—C12—H12C109.5
C1—C2—C3124.1 (3)C18—C13—C14120.33 (19)
C1—C2—H2118.0C18—C13—S1120.05 (15)
C3—C2—H2118.0C14—C13—S1119.59 (16)
C2—C3—N1113.3 (2)C15—C14—C13118.9 (2)
C2—C3—H3A108.9C15—C14—H14120.6
N1—C3—H3A108.9C13—C14—H14120.6
C2—C3—H3B108.9C16—C15—C14122.0 (2)
N1—C3—H3B108.9C16—C15—H15119.0
H3A—C3—H3B107.7C14—C15—H15119.0
N1—C4—C5106.4 (2)C15—C16—C17118.1 (2)
N1—C4—H4126.8C15—C16—C19121.5 (2)
C5—C4—H4126.8C17—C16—C19120.4 (2)
C4—C5—C10137.2 (2)C18—C17—C16121.1 (2)
C4—C5—C6103.6 (2)C18—C17—H17119.5
C10—C5—C6119.2 (2)C16—C17—H17119.5
N2—C6—C7126.8 (2)C17—C18—C13119.67 (19)
N2—C6—C5111.7 (2)C17—C18—H18120.2
C7—C6—C5121.4 (2)C13—C18—H18120.2
C8—C7—C6117.9 (2)C16—C19—H19A109.5
C8—C7—H7121.0C16—C19—H19B109.5
C6—C7—H7121.0H19A—C19—H19B109.5
C7—C8—C9121.8 (2)C16—C19—H19C109.5
C7—C8—H9119.1H19A—C19—H19C109.5
C9—C8—H9119.1H19B—C19—H19C109.5
C10—C9—C8121.43 (19)N2—N1—C4114.5 (2)
C10—C9—N3119.84 (17)N2—N1—C3119.7 (2)
C8—C9—N3118.68 (18)C4—N1—C3125.8 (2)
O1—C10—C9116.71 (18)N1—N2—C6103.7 (2)
O1—C10—C5125.09 (19)C9—N3—S1121.32 (13)
C9—C10—C5118.13 (18)C9—N3—H3N116.5
O1—C11—C12108.4 (2)S1—N3—H3N108.9
O1—C11—H11B110.0C10—O1—C11120.3 (2)
C12—C11—H11B110.0O2—S1—O3118.36 (10)
O1—C11—H11A110.0O2—S1—N3108.69 (9)
C12—C11—H11A110.0O3—S1—N3104.65 (9)
H11B—C11—H11A108.4O2—S1—C13107.78 (9)
C11—C12—H12B109.5O3—S1—C13108.99 (10)
C11—C12—H12A109.5N3—S1—C13107.96 (9)
H12B—C12—H12A109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H9···O20.932.482.991 (3)115
N3—H3N···O3i0.842.142.960 (2)164
C17—H17···O2ii0.932.543.333 (3)144
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H9···O20.932.482.991 (3)115
N3—H3N···O3i0.842.142.960 (2)164
C17—H17···O2ii0.932.543.333 (3)144
Symmetry codes: (i) x+1, y+1, z+1; (ii) x, y+1, z.
 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

First citationAbbassi, N., Chicha, H., Rakib, E. M., Hannioui, A., Alaoui, M., Hajjaji, A., Geffken, D., Aiello, C., Gangemi, R., Rosano, C. & Viale, M. (2012). Eur. J. Med. Chem. 57, 240–249.  Web of Science CrossRef CAS PubMed Google Scholar
First citationAbbassi, N., Rakib, E. M., Hannioui, A., Saadi, M. & El Ammari, L. (2013). Acta Cryst. E69, o190–o191.  CSD CrossRef CAS IUCr Journals Google Scholar
First citationAbbate, F., Casini, A., Owa, T., Scozzafava, A. & Supuran, C. T. (2004). Bioorg. Med. Chem. Lett. 14, 217–223.  Web of Science CrossRef PubMed CAS Google Scholar
First citationBouissane, L., El Kazzouli, S., Leonce, S., Pffeifer, P., Rakib, M. E., Khouili, M. & Guillaumet, G. (2006). Bioorg. Med. Chem. 14, 1078–1088.  Web of Science CrossRef PubMed CAS Google Scholar
First citationBruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationDrews, J. (2000). Science, 287, 1960–1964.  Web of Science CrossRef PubMed CAS Google Scholar
First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationGhorab, M. M., Ragab, F. A. & Hamed, M. M. (2009). Eur. J. Med. Chem. 44, 4211–4217.  Web of Science CrossRef PubMed CAS Google Scholar
First citationRostom, S. A. (2006). Bioorg. Med. Chem. 14, 6475–6485.  Web of Science CrossRef PubMed CAS 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. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSupuran, C. T. & Scozzafava, A. (2001). Immun. Endoc. Metab. Agents Med. Chem. 1, 61–97.  CrossRef CAS Google Scholar
First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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