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

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ISSN: 2056-9890

3-Chloro-6-[4-(2-pyrid­yl)piperazin-1-yl]pyridazine

aDepartment of Chemistry, Emory University, Atlanta, GA-30322, USA, bDepartment of Chemistry, Faculty of Pharmacy, Mersin University, Mersin TR-33169, Turkey, cDepartment of Pharmaceutical Chemistry, Faculty of Pharmacy, Mersin University, Mersin TR-33169, Turkey, and dDepartment of Pharmaceutical Chemistry, Faculty of Pharmacy, Gazi University, Ankara TR-06330, Turkey
*Correspondence e-mail: hakan.arslan.acad@gmail.com

(Received 23 November 2009; accepted 25 November 2009; online 4 December 2009)

In the title compound, C13H14ClN5, the piperazine ring adopts a chair conformation and the dihedral angle between the aromatic rings is 13.91 (7)°. The crystal structure is stabilized by weak inter­molecular C—H⋯N hydrogen-bond inter­actions.

Related literature

For the synthesis, structures and analgesic and anti-inflammatory activity of substituted pyridazine derivatives, see: Boissier et al. (1963[Boissier, J. R., Ratouis, R. & Dumont, C. (1963). J. Med. Chem. 6, 541-544.]); Gokce et al. (2001[Gokce, M., Dogruer, D. S. & Sahin, M. F. (2001). Il Farmaco, 56, 233-237.], 2004[Gokce, M., Sahin, M. F., Kupeli, E. & Yesilada, E. (2004). Arzneim. Forsch. 54, 396-401.], 2005[Gokce, M., Bakır, G., Sahin, M. F., Kupeli, E. & Yesilada, E. (2005). Arzneim. Forsch. 55, 318-325.], 2009[Gokce, M., Utku, S. & Kupeli, E. (2009). Eur. J. Med. Chem. 44, 3760-3764.]); Sahin et al. (2004[Sahin, M. F., Badıcoglu, B., Gokce, M., Kupeli, E. & Yesilada, E. (2004). Arch. Pharm. 337, 445-452.]); Dundar et al. (2007[Dundar, Y., Gokce, M., Kupeli, E. & Sahin, M. F. (2007). Arzneim. Forsch. 57, 777-781.]). For general background to non-opioid analgesic derivatives, see: Sato et al. (1981[Sato, M., Ishizuka, Y. & Yamagucci, A. (1981). Arzneim. Forsch. 31, 1738-1745.]); Banoglu et al. (2004[Banoglu, E., Akoglu, C., Unlu, S., Kupeli, E., Yesilada, E. & Sahin, M. F. (2004). Arch. Pharm. 337, 7-14.]); Giovannoni et al. (2003[Giovannoni, M. P., Vergelli, C., Chelardini, C., Nicoletta, G., Bartolini, A. & Dal Piaz, V. (2003). J. Med. Chem. 46, 1055-1059.])·For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C13H14ClN5

  • Mr = 275.74

  • Triclinic, [P \overline 1]

  • a = 5.912 (3) Å

  • b = 8.088 (5) Å

  • c = 13.689 (8) Å

  • α = 83.359 (9)°

  • β = 83.019 (9)°

  • γ = 75.168 (9)°

  • V = 625.5 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.30 mm−1

  • T = 296 K

  • 0.16 × 0.15 × 0.14 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.954, Tmax = 0.959

  • 11395 measured reflections

  • 3275 independent reflections

  • 2264 reflections with I > 2σ(I)

  • Rint = 0.049

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.095

  • S = 0.95

  • 3275 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯N1i 0.93 2.58 3.346 (3) 140
Symmetry code: (i) x+1, y, z.

Data collection: APEX2 (Bruker (2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The opioid derivative analgesics have significant side effects, therefore, the current research is focused on non-opioid analgesics that do not have serious side effects but are as effective as the opioids. One of the non-opioid analgesic derivatives is emorfazone which has a substituted pyridazine (Sato et al., 1981). In addition, some pyridazinone derivatives bearing an alkylpiperazinyl alkyl moiety also show interesting antinociceptive activity (Banoglu et al., 2004; Giovannoni et al., 2003).

Recently, our team focused on the synthesis, characterization, and analgesics-anti-inflammatory activity of substituted pyridazine derivatives (Dundar et al., 2007; Gokce et al., 2001, 2004, 2005, 2009; Sahin et al., 2004). The compound, 3-chloro-6-(4-pyridin-2-ylpiperazin-1-yl)pyridazine, (I), Scheme 1, is one example and in this article we report on the crystal structure of the title compound, Figure 1.

The molecular structure of (I) consists of 3-chloropyridazine and pyridine arms connected to a piperazine ring. The 3-chloropyridazine and pyridine rings are planar with a maximum deviation of 0.006 (1) Å for atom C4 and -0.014 (2) Å for atom C12. The dihedral angle between these two rings is 13.91 (7) °. The piperazine ring adopts a chair conformation. This is confirmed by the puckering parameters q2 = 0.0056 (13) Å, q3 = -0.5388 (13) Å, QT = 0.5388 (13) Å, θ = 179.67 (14) ° and ϕ = 221 (14) ° (Cremer & Pople, 1975).

The conformations of the 3-chloropyridazine and pyridine rings are best described by the torsion angles of -155.41 (12) ° and 156.51 (12) ° for C4—N3—C5—C6 and C9—N4—C7—C8, respectively; thus they adopt - antiperiplanar and + antiperiplanar conformations, respectively.

The crystal packing is dominated by weak intermolecular C3—H3···N1 (1 + x, y, z) hydrogen bonds, with H···N = 2.58 Å and a C—H···N angle of 140 ° (Figure 2).

Related literature top

For the synthesis, structures and analgesic and anti-inflammatory activity of substituted pyridazine derivatives, see: Boissier et al. (1963); Gokce et al. (2001, 2004, 2005, 2009); Sahin et al. (2004); Dundar et al. (2007). For general background to non-opioid analgesic derivatives, see: Sato et al. (1981); Banoglu et al. (2004); Giovannoni et al. (2003).For puckering parameters, see: Cremer & Pople (1975).

Experimental top

A mixture of 3,6-dichloropyridazine, (II), (1.7 mol) and 1-(2-pyridyl)piperazine, (III), (2.0 mol) in ethanol (10 ml) was heated under reflux for 4 h after which the mixture was cooled to room temperature (Figure 3) (Boissier et al., 1963). The resulting crude precipitate was filtered off and purified by repeated washing with small portions of cold ethanol. The precipitate formed was crystallized from CH2Cl2:ethanol (5:10) to give the compound 3-chloro-6-(4-pyridin-2-ylpiperazin-1-yl) pyridazine, (I), as white crystals. Yields: 0.270 g, 58%. M.p.: 153 °C. 1H NMR (DMSO-d6) δ: 8.16–8.13 (d, 1H, pyridyl), 7.63–7.56 (m, 2H, pyridyl), 7.47–7.44 (d, 1H, pyridazin), 6.93–6.89 (d, 1H, pyridyl), 6.75–6.66 (d, 1H, pyridazin), 3.73–3.62(m, 4H, piperazine), 3.17–3.14 (m, 4H, piperazine). MS (EI) m/z: 276 (M+). Anal. Calc. for C13H14N5Cl: C, 56.63; H, 5.12; N, 25.40%. Found: C, 56.60; H, 5.10; N, 24.42%.

Refinement top

The H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H distances of 0.93 Å (CH) or 0.97 Å (CH2), and with Uiso(H) = 1.2Ueq of the parent atoms.

Computing details top

Data collection: APEX2 (Bruker (2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. The molecular packing of (I). The hydrogen bonds are shown as dashed lines.
[Figure 3] Fig. 3. Preparation of compound (I)
3-Chloro-6-[4-(2-pyridyl)piperazin-1-yl]pyridazine top
Crystal data top
C13H14ClN5Z = 2
Mr = 275.74F(000) = 288
Triclinic, P1Dx = 1.464 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.912 (3) ÅCell parameters from 2718 reflections
b = 8.088 (5) Åθ = 2.6–28.2°
c = 13.689 (8) ŵ = 0.30 mm1
α = 83.359 (9)°T = 296 K
β = 83.019 (9)°Block, colourless
γ = 75.168 (9)°0.16 × 0.15 × 0.14 mm
V = 625.5 (6) Å3
Data collection top
Bruker APEXII CCD
diffractometer
3275 independent reflections
Radiation source: fine-focus sealed tube2264 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.049
ϕ and ω scansθmax = 29.0°, θmin = 1.5°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 87
Tmin = 0.954, Tmax = 0.959k = 1011
11395 measured reflectionsl = 1818
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 0.95 w = 1/[σ2(Fo2) + (0.0433P)2]
where P = (Fo2 + 2Fc2)/3
3275 reflections(Δ/σ)max = 0.001
172 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C13H14ClN5γ = 75.168 (9)°
Mr = 275.74V = 625.5 (6) Å3
Triclinic, P1Z = 2
a = 5.912 (3) ÅMo Kα radiation
b = 8.088 (5) ŵ = 0.30 mm1
c = 13.689 (8) ÅT = 296 K
α = 83.359 (9)°0.16 × 0.15 × 0.14 mm
β = 83.019 (9)°
Data collection top
Bruker APEXII CCD
diffractometer
3275 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2264 reflections with I > 2σ(I)
Tmin = 0.954, Tmax = 0.959Rint = 0.049
11395 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 0.95Δρmax = 0.27 e Å3
3275 reflectionsΔρmin = 0.23 e Å3
172 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
C10.2600 (3)1.08679 (18)0.14549 (10)0.0258 (3)
C20.4977 (3)1.05027 (18)0.15814 (10)0.0262 (3)
H20.60451.08560.10980.031*
C30.5676 (2)0.96086 (18)0.24396 (10)0.0233 (3)
H30.72480.93140.25630.028*
C40.3929 (2)0.91394 (16)0.31412 (10)0.0183 (3)
C50.2554 (2)0.78257 (18)0.47211 (9)0.0191 (3)
H5A0.24470.67100.45650.023*
H5B0.10660.86390.46130.023*
C60.2997 (2)0.77262 (18)0.57925 (10)0.0201 (3)
H6A0.29020.88690.59730.024*
H6B0.17950.72810.62060.024*
C70.7198 (2)0.71363 (18)0.53092 (9)0.0195 (3)
H7A0.86760.63120.54170.023*
H7B0.73250.82460.54670.023*
C80.6760 (2)0.72468 (17)0.42325 (10)0.0191 (3)
H8A0.79570.77010.38220.023*
H8B0.68600.61070.40470.023*
C90.5772 (2)0.58513 (17)0.69070 (10)0.0195 (3)
C100.3966 (3)0.57581 (19)0.76644 (11)0.0273 (3)
H100.24110.63070.75710.033*
C110.4545 (3)0.4840 (2)0.85437 (11)0.0326 (4)
H110.33730.47540.90520.039*
C120.6857 (3)0.4044 (2)0.86779 (11)0.0335 (4)
H120.72770.33930.92630.040*
C130.8513 (3)0.4253 (2)0.79115 (11)0.0317 (4)
H131.00800.37430.80020.038*
Cl10.15611 (8)1.19962 (6)0.03723 (3)0.04376 (16)
N10.1002 (2)1.04206 (16)0.21036 (9)0.0273 (3)
N20.1664 (2)0.95301 (15)0.29644 (8)0.0240 (3)
N30.44321 (19)0.83591 (14)0.40660 (8)0.0185 (3)
N40.53064 (19)0.66186 (14)0.59658 (8)0.0190 (3)
N50.8031 (2)0.51407 (15)0.70410 (9)0.0259 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0272 (8)0.0267 (8)0.0218 (7)0.0052 (6)0.0029 (6)0.0016 (6)
C20.0253 (8)0.0305 (8)0.0236 (7)0.0119 (7)0.0053 (6)0.0019 (6)
C30.0171 (7)0.0278 (8)0.0256 (7)0.0084 (6)0.0024 (6)0.0035 (6)
C40.0171 (7)0.0169 (7)0.0215 (7)0.0052 (5)0.0011 (5)0.0050 (5)
C50.0120 (7)0.0230 (7)0.0219 (7)0.0054 (6)0.0007 (5)0.0006 (5)
C60.0129 (7)0.0240 (7)0.0220 (7)0.0033 (6)0.0015 (5)0.0015 (6)
C70.0121 (7)0.0226 (7)0.0239 (7)0.0057 (6)0.0001 (5)0.0010 (5)
C80.0107 (7)0.0217 (7)0.0239 (7)0.0031 (5)0.0017 (5)0.0028 (5)
C90.0198 (7)0.0182 (7)0.0219 (7)0.0057 (6)0.0031 (6)0.0033 (5)
C100.0208 (8)0.0327 (8)0.0262 (8)0.0048 (7)0.0005 (6)0.0011 (6)
C110.0320 (9)0.0415 (9)0.0236 (8)0.0123 (8)0.0016 (7)0.0023 (7)
C120.0369 (10)0.0389 (9)0.0240 (8)0.0077 (8)0.0103 (7)0.0045 (7)
C130.0246 (9)0.0378 (9)0.0314 (8)0.0030 (7)0.0101 (7)0.0000 (7)
Cl10.0423 (3)0.0562 (3)0.0281 (2)0.0095 (2)0.00750 (18)0.01386 (18)
N10.0230 (7)0.0329 (7)0.0246 (6)0.0060 (6)0.0038 (5)0.0034 (5)
N20.0166 (6)0.0297 (7)0.0242 (6)0.0054 (5)0.0023 (5)0.0033 (5)
N30.0115 (6)0.0229 (6)0.0198 (6)0.0039 (5)0.0009 (4)0.0001 (5)
N40.0119 (6)0.0230 (6)0.0209 (6)0.0042 (5)0.0003 (5)0.0007 (5)
N50.0201 (7)0.0307 (7)0.0259 (7)0.0037 (5)0.0052 (5)0.0014 (5)
Geometric parameters (Å, º) top
C1—N11.3071 (19)C7—H7A0.9700
C1—C21.388 (2)C7—H7B0.9700
C1—Cl11.7401 (16)C8—N31.4661 (18)
C2—C31.3574 (19)C8—H8A0.9700
C2—H20.9300C8—H8B0.9700
C3—C41.4170 (18)C9—N51.3377 (18)
C3—H30.9300C9—N41.3909 (17)
C4—N21.3401 (18)C9—C101.405 (2)
C4—N31.3784 (17)C10—C111.372 (2)
C5—N31.4617 (17)C10—H100.9300
C5—C61.5104 (19)C11—C121.378 (2)
C5—H5A0.9700C11—H110.9300
C5—H5B0.9700C12—C131.372 (2)
C6—N41.4582 (18)C12—H120.9300
C6—H6A0.9700C13—N51.3402 (18)
C6—H6B0.9700C13—H130.9300
C7—N41.4635 (17)N1—N21.3534 (16)
C7—C81.5159 (19)
N1—C1—C2124.64 (13)N3—C8—C7110.54 (11)
N1—C1—Cl1115.24 (12)N3—C8—H8A109.5
C2—C1—Cl1120.12 (11)C7—C8—H8A109.5
C3—C2—C1117.20 (13)N3—C8—H8B109.5
C3—C2—H2121.4C7—C8—H8B109.5
C1—C2—H2121.4H8A—C8—H8B108.1
C2—C3—C4117.76 (14)N5—C9—N4116.30 (12)
C2—C3—H3121.1N5—C9—C10121.67 (13)
C4—C3—H3121.1N4—C9—C10121.97 (13)
N2—C4—N3116.16 (11)C11—C10—C9118.58 (14)
N2—C4—C3121.66 (12)C11—C10—H10120.7
N3—C4—C3122.04 (13)C9—C10—H10120.7
N3—C5—C6111.31 (11)C10—C11—C12120.29 (14)
N3—C5—H5A109.4C10—C11—H11119.9
C6—C5—H5A109.4C12—C11—H11119.9
N3—C5—H5B109.4C13—C12—C11117.17 (14)
C6—C5—H5B109.4C13—C12—H12121.4
H5A—C5—H5B108.0C11—C12—H12121.4
N4—C6—C5110.91 (11)N5—C13—C12124.63 (14)
N4—C6—H6A109.5N5—C13—H13117.7
C5—C6—H6A109.5C12—C13—H13117.7
N4—C6—H6B109.5C1—N1—N2119.04 (12)
C5—C6—H6B109.5C4—N2—N1119.68 (11)
H6A—C6—H6B108.0C4—N3—C5118.35 (11)
N4—C7—C8111.62 (11)C4—N3—C8121.18 (11)
N4—C7—H7A109.3C5—N3—C8112.41 (11)
C8—C7—H7A109.3C9—N4—C6120.47 (11)
N4—C7—H7B109.3C9—N4—C7118.98 (11)
C8—C7—H7B109.3C6—N4—C7112.49 (11)
H7A—C7—H7B108.0C9—N5—C13117.56 (12)
N1—C1—C2—C30.4 (2)C3—C4—N3—C5176.37 (12)
Cl1—C1—C2—C3179.57 (11)N2—C4—N3—C8154.15 (12)
C1—C2—C3—C40.8 (2)C3—C4—N3—C830.0 (2)
C2—C3—C4—N21.2 (2)C6—C5—N3—C4155.41 (12)
C2—C3—C4—N3174.44 (13)C6—C5—N3—C855.41 (15)
N3—C5—C6—N454.49 (15)C7—C8—N3—C4157.23 (12)
N4—C7—C8—N353.56 (15)C7—C8—N3—C554.57 (15)
N5—C9—C10—C113.3 (2)N5—C9—N4—C6167.32 (12)
N4—C9—C10—C11173.85 (13)C10—C9—N4—C615.4 (2)
C9—C10—C11—C120.6 (2)N5—C9—N4—C720.90 (18)
C10—C11—C12—C131.6 (3)C10—C9—N4—C7161.84 (13)
C11—C12—C13—N51.5 (3)C5—C6—N4—C9156.99 (12)
C2—C1—N1—N20.3 (2)C5—C6—N4—C754.58 (15)
Cl1—C1—N1—N2179.64 (10)C8—C7—N4—C9156.51 (12)
N3—C4—N2—N1174.73 (12)C8—C7—N4—C654.56 (15)
C3—C4—N2—N11.2 (2)N4—C9—N5—C13173.88 (13)
C1—N1—N2—C40.7 (2)C10—C9—N5—C133.4 (2)
N2—C4—N3—C57.76 (18)C12—C13—N5—C91.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···N1i0.932.583.346 (3)140
Symmetry code: (i) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC13H14ClN5
Mr275.74
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)5.912 (3), 8.088 (5), 13.689 (8)
α, β, γ (°)83.359 (9), 83.019 (9), 75.168 (9)
V3)625.5 (6)
Z2
Radiation typeMo Kα
µ (mm1)0.30
Crystal size (mm)0.16 × 0.15 × 0.14
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.954, 0.959
No. of measured, independent and
observed [I > 2σ(I)] reflections
11395, 3275, 2264
Rint0.049
(sin θ/λ)max1)0.682
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.095, 0.95
No. of reflections3275
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.27, 0.23

Computer programs: APEX2 (Bruker (2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···N1i0.932.583.346 (3)140
Symmetry code: (i) x+1, y, z.
 

References

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