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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2777–o2778.
Published online 2010 October 9. doi:  10.1107/S160053681003936X
PMCID: PMC3008975

3-Ethyl-4-[3-(1H-imidazol-1-yl)prop­yl]-5-phenyl-4H-1,2,4-triazole dihydrate

Abstract

In the title compound, C16H19N5·2H2O, the triazole ring makes dihedral angles of 70.61 (6) and 41.89 (8)°, respectively, with the imidazole and benzene rings. The water mol­ecules are involved in inter­molecular O—H(...)N and O—H(...)O hydrogen bonds, which stabilize the crystal packing.

Related literature

For a related structure, see: Rizzoli et al. (2009 [triangle]); Kalkan et al. (2007 [triangle]). For bond lengths and angles in triazole rings, see: Thenmozhi et al. (2010 [triangle]); Rizzoli et al. (2009 [triangle]); Dolzhenko et al. (2010 [triangle]); Ocak Ískeleli et al. (2005 [triangle]); Ünver et al. (2010 [triangle]). For the biological activity of triazole Schiff bases, see: Thenmozhi et al. (2010 [triangle]) and of 1,2,4-triazole derivatives, see: Ünver et al. (2010 [triangle]). For the search for and synthesis of new anti­biotics, see: Köysal et al. (2006 [triangle]). For the synthesis, see: Ünver et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2777-scheme1.jpg

Experimental

Crystal data

  • C16H19N5·2H2O
  • M r = 317.39
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2777-efi1.jpg
  • a = 11.0787 (16) Å
  • b = 9.8428 (8) Å
  • c = 16.3289 (18) Å
  • β = 105.602 (9)°
  • V = 1715.0 (3) Å3
  • Z = 4
  • Cu Kα radiation
  • μ = 0.68 mm−1
  • T = 293 K
  • 0.30 × 0.20 × 0.20 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • Absorption correction: ψ scan North et al. (1968 [triangle]) T min = 0.821, T max = 0.876
  • 3030 measured reflections
  • 2868 independent reflections
  • 2166 reflections with I > 2σ(I)
  • R int = 0.029
  • 2 standard reflections every 60 min intensity decay: none

Refinement

  • R[F 2 > 2σ(F 2)] = 0.045
  • wR(F 2) = 0.123
  • S = 1.08
  • 2868 reflections
  • 226 parameters
  • 6 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.19 e Å−3
  • Δρmin = −0.18 e Å−3

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 [triangle]); cell refinement: CAD-4 EXPRESS; data reduction: MolEN (Fair, 1990 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ZORTEP (Zsolnai, 1997 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Selected geometric parameters (Å, °)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681003936X/jh2213sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681003936X/jh2213Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

DÜ and ED thank the Research Fund of Karadeniz Technical University for its support of this work.

supplementary crystallographic information

Comment

The biological importance of imidazoles and triazoles has stimulated much work on these heterocycles. 1,2,4-Triazole is a basic aromatic ring and possesses good coordination ability due to the presence of nitrogen atoms (Thenmozhi et al.,2010). 1,2,4-Triazole compounds posses important pharmacology activities such as antifungal and antiviral activities. Examples of such compounds bearing the 1,2,4-Triazole residues are fluconazole, the powerful azole antifungal agent as well as the potent antiviral N-nucleoside ribavirin. Furthermore various 1,2,4-Triazole derivatives have been reported as fungicidal, insecticidal, antimicrobial as well as anticonvulsants, antidepressants and plant growth regulator anticoagulants (Ünver et al., 2010). 1,2,4-Triazole derivatives are also used to build polymetallic complexes. Compounds derived from triazole possess antimicrobial, analgesic, anti-inflammatory, local anesthetic, antineoplastic and antimalarial properties. Some triazole Schiff bases also exhibit antiproliferative and anticancer activities (Thenmozhi et al., 2010). 1,2,4-Triazole moieties interact strongly with heme iron and aromatic substituents on the triazoles are very effective for interacting with the active site of aromatase. Furthermore, it was reported that compounds having triazole moieties such as Vorozole, Anastrozole and Letrozole appear to be very effective aromatese inhibitors very useful for preventing breast cancer (Ünver et al., 2010). Some of the azole derivatives used as common antibiotics, such as amphotericin B, exhibit toxic effects on humans along with antimicrobial effects. Although different antimicrobial agents are used in the treatment of microbial infections, an increasing resistance to these drugs is observed. Therefore, the search for and synthesis of new antibiotics different from commonly used ones is of current importance (Köysal et al., 2006). In a search for new triazole compounds with better biological activity, the title compound (I), was synthesized. We report here the crystal structure of the title compound, (I) (Fig.1), a new 1,2,4-triazole derivative. The compound (I) crystallizes as a dihydrate, the bond lengths and angles (Table 1) are generally normal in the triazole ring (Thenmozhi et al., 2010; Rizzoli et al., 2009; Dolzhenko et al., 2010; Ocak Ískeleli et al., 2005; Ünver et al., 2010). Atom N3 has a trigonal configuration, the sum of the three bond angles around them being 360° (Kalkan et al., 2007). The dihedral angles between the planes A(N1/N2/C7/N3/C8), B(N4/C14/N5/C15/C16) and C(C1/C2/C3/C4/C5/C6) are A/B = 70.61 (6)°, A/C = 41.89 (8)° and B/C = 68.16 (7)°. The triazole ring is essentially planar with r.m.s deviation of 0.0046Å (Dolzhenko et al., 2010). The C—N bond lengths in the triazole ring of all molecules lie in the range of 1.260 (3)–1.349 (4) Å. These are longer than a typical double C═ N bond [1.269 (2) Å], but shorter than a C—N single bond [1.443 (4) Å], (Thenmozhi et al., 2010) indicating the possibility of electron delocalization. The N3–C11–C12–C13 torsion angle of 172.00 (15)° indicates that the triazole ring and the imidazole moiety has an E-configuration across the C11–C12 bond. This configuration is stabilized by an intramolecular C11–H11···N4 hydrogen bond with H11···N4 distance of 2.54 Å. The uncoordinated water molecules are involved in intermolecular O–H···O and O–H···N hydrogen bonds (Table 2), which stabilize the crystal packing.

Experimental

The compound was synthesized by published method (Ünver et al., 2009).

Refinement

Water H atoms were located in a difference Fourier map and isotropically refined with O—H distance restraints of 0.90 (1) Å. All the other H atoms were positioned geometrically and treated as riding on their parent atoms, with C—H = 0.93Å (aromatic) and 0.97Å (methylene), N—H = 0.86 Å, and refined using a riding model with Uiso(H) = 1.2Ueq or 1.5Ueq(parent atom). In the absence of significant anomalous scattering effects, Friedel pairs were merged.

Figures

Fig. 1.
The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
Crystal packing of the title compound viewed along the a axiS. Intermolecular O—H···O and O—H···N hydrogen bonds are shown as dashed lines.
Fig. 3.
Crystal Packing of the title compound with hydrogen bonds.

Crystal data

C16H19N5·2H2OF(000) = 680
Mr = 317.39Dx = 1.229 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54180 Å
a = 11.0787 (16) ÅCell parameters from 25 reflections
b = 9.8428 (8) Åθ = 20–30°
c = 16.3289 (18) ŵ = 0.68 mm1
β = 105.602 (9)°T = 293 K
V = 1715.0 (3) Å3Block, colourless
Z = 40.30 × 0.20 × 0.20 mm

Data collection

Enraf–Nonius CAD-4 Diffractometer2166 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.029
graphiteθmax = 64.9°, θmin = 4.1°
ω–2τ scanh = 0→13
Absorption correction: ψ scan North et al. (1968)k = 0→11
Tmin = 0.821, Tmax = 0.876l = −19→18
3030 measured reflections2 standard reflections every 60 min
2868 independent reflections intensity decay: none

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.123w = 1/[σ2(Fo2) + (0.0676P)2 + 0.2107P] where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
2868 reflectionsΔρmax = 0.19 e Å3
226 parametersΔρmin = −0.17 e Å3
6 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0246 (12)

Special details

Experimental. Number of psi-scan sets used was 5 Theta correction was applied. Averaged transmission function was used. No Fourier smoothing was applied.
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)

xyzUiso*/Ueq
C11.10619 (16)0.09615 (18)0.08555 (11)0.0519 (4)
H11.05540.02180.08780.062*
C21.23425 (18)0.0845 (2)0.11690 (12)0.0609 (5)
H21.26920.00260.14000.073*
C31.31051 (18)0.1935 (2)0.11417 (12)0.0655 (6)
H31.39700.18550.13540.079*
C41.25803 (18)0.3152 (2)0.07964 (12)0.0623 (5)
H41.30940.38930.07790.075*
C51.13010 (17)0.32727 (17)0.04779 (11)0.0509 (4)
H51.09560.40920.02420.061*
C61.05207 (15)0.21742 (16)0.05067 (10)0.0429 (4)
C70.91650 (15)0.23322 (16)0.01343 (10)0.0430 (4)
C80.71432 (16)0.23090 (19)−0.00821 (11)0.0529 (5)
C90.58650 (18)0.2091 (3)0.00312 (15)0.0772 (6)
H9A0.56890.11240.00050.093*
H9B0.58560.24060.05920.093*
C100.4853 (2)0.2794 (3)−0.06124 (19)0.1100 (10)
H10A0.50270.3750−0.06000.165*
H10B0.40660.2646−0.04860.165*
H10C0.48130.2441−0.11670.165*
C110.83527 (17)0.11825 (17)0.12819 (10)0.0496 (4)
H11A0.77540.15760.15510.060*
H11B0.91850.13590.16480.060*
C120.81484 (18)−0.03413 (18)0.12166 (11)0.0571 (5)
H12A0.8667−0.07320.08840.069*
H12B0.7279−0.05290.09250.069*
C130.8473 (2)−0.0997 (2)0.20926 (13)0.0658 (5)
H13A0.7918−0.06430.24110.079*
H13B0.8335−0.19690.20290.079*
C141.0814 (2)−0.1225 (2)0.23923 (13)0.0618 (5)
H141.0804−0.18140.19450.074*
C151.1436 (2)0.0064 (2)0.34639 (14)0.0700 (6)
H151.19590.05430.39120.084*
C161.0180 (2)0.0092 (2)0.32597 (12)0.0655 (5)
H160.96850.05840.35320.079*
N10.86819 (13)0.29858 (15)−0.05759 (9)0.0524 (4)
N20.73910 (14)0.29737 (16)−0.07142 (10)0.0572 (4)
N30.82282 (12)0.18678 (13)0.04670 (8)0.0455 (4)
N40.97689 (15)−0.07477 (15)0.25699 (9)0.0564 (4)
N51.18406 (17)−0.07686 (18)0.29187 (11)0.0692 (5)
O10.60569 (16)0.10016 (18)0.26136 (10)0.0807 (5)
O20.43707 (15)−0.11055 (19)0.28415 (13)0.0920 (6)
H1A0.554 (2)0.030 (2)0.2642 (16)0.127 (11)*
H1B0.650 (2)0.121 (3)0.3147 (9)0.134 (11)*
H2A0.3579 (13)−0.096 (2)0.2882 (17)0.105 (9)*
H2B0.444 (2)−0.2016 (12)0.277 (2)0.154 (14)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0520 (10)0.0489 (10)0.0551 (10)−0.0035 (8)0.0146 (8)0.0050 (8)
C20.0562 (11)0.0673 (12)0.0575 (11)0.0090 (9)0.0124 (8)0.0122 (9)
C30.0467 (11)0.0881 (15)0.0583 (11)−0.0024 (10)0.0086 (8)−0.0020 (10)
C40.0537 (11)0.0680 (12)0.0668 (12)−0.0186 (9)0.0190 (9)−0.0075 (10)
C50.0543 (11)0.0451 (9)0.0560 (10)−0.0047 (8)0.0193 (8)−0.0015 (8)
C60.0464 (10)0.0417 (8)0.0423 (8)−0.0029 (7)0.0152 (7)−0.0023 (7)
C70.0455 (9)0.0376 (8)0.0483 (9)−0.0039 (7)0.0169 (7)−0.0005 (7)
C80.0472 (10)0.0528 (10)0.0598 (10)−0.0034 (8)0.0163 (8)0.0020 (8)
C90.0505 (12)0.0929 (16)0.0929 (15)−0.0052 (11)0.0271 (11)0.0124 (13)
C100.0514 (14)0.151 (3)0.131 (2)0.0045 (15)0.0297 (14)0.031 (2)
C110.0578 (10)0.0464 (9)0.0489 (9)−0.0042 (8)0.0218 (8)−0.0010 (7)
C120.0665 (12)0.0479 (10)0.0615 (11)−0.0122 (8)0.0252 (9)−0.0007 (8)
C130.0780 (14)0.0530 (11)0.0757 (13)−0.0041 (10)0.0366 (11)0.0124 (10)
C140.0839 (15)0.0492 (10)0.0594 (11)0.0147 (10)0.0314 (11)0.0078 (9)
C150.0886 (16)0.0605 (12)0.0631 (12)0.0040 (11)0.0240 (11)0.0049 (10)
C160.0951 (16)0.0532 (11)0.0590 (11)0.0097 (10)0.0394 (11)0.0041 (9)
N10.0461 (8)0.0548 (9)0.0562 (8)−0.0011 (7)0.0137 (6)0.0098 (7)
N20.0439 (9)0.0624 (9)0.0638 (9)−0.0005 (7)0.0121 (7)0.0096 (8)
N30.0477 (8)0.0424 (7)0.0485 (7)−0.0045 (6)0.0163 (6)0.0002 (6)
N40.0741 (11)0.0474 (8)0.0559 (8)0.0066 (7)0.0314 (8)0.0092 (7)
N50.0786 (12)0.0630 (11)0.0704 (10)0.0143 (9)0.0278 (9)0.0130 (9)
O10.0767 (11)0.0899 (12)0.0706 (10)−0.0057 (9)0.0114 (8)0.0019 (8)
O20.0619 (10)0.0805 (12)0.1268 (15)0.0036 (8)0.0135 (9)−0.0038 (10)

Geometric parameters (Å, °)

C1—C21.377 (2)C11—N31.465 (2)
C1—C61.387 (2)C11—C121.516 (2)
C1—H10.9300C11—H11A0.9700
C2—C31.373 (3)C11—H11B0.9700
C2—H20.9300C12—C131.522 (3)
C3—C41.384 (3)C12—H12A0.9700
C3—H30.9300C12—H12B0.9700
C4—C51.377 (3)C13—N41.459 (2)
C4—H40.9300C13—H13A0.9700
C5—C61.393 (2)C13—H13B0.9700
C5—H50.9300C14—N51.307 (3)
C6—C71.469 (2)C14—N41.352 (2)
C7—N11.308 (2)C14—H140.9300
C7—N31.373 (2)C15—C161.341 (3)
C8—N21.312 (2)C15—N51.371 (3)
C8—N31.363 (2)C15—H150.9300
C8—C91.492 (3)C16—N41.372 (2)
C9—C101.485 (3)C16—H160.9300
C9—H9A0.9700N1—N21.387 (2)
C9—H9B0.9700O1—H1A0.906 (10)
C10—H10A0.9600O1—H1B0.902 (10)
C10—H10B0.9600O2—H2A0.909 (9)
C10—H10C0.9600O2—H2B0.910 (10)
C2—C1—C6120.80 (16)N3—C11—H11A108.6
C2—C1—H1119.6C12—C11—H11A108.6
C6—C1—H1119.6N3—C11—H11B108.6
C3—C2—C1120.29 (18)C12—C11—H11B108.6
C3—C2—H2119.9H11A—C11—H11B107.6
C1—C2—H2119.9C11—C12—C13111.13 (15)
C2—C3—C4119.64 (18)C11—C12—H12A109.4
C2—C3—H3120.2C13—C12—H12A109.4
C4—C3—H3120.2C11—C12—H12B109.4
C5—C4—C3120.35 (18)C13—C12—H12B109.4
C5—C4—H4119.8H12A—C12—H12B108.0
C3—C4—H4119.8N4—C13—C12112.37 (15)
C4—C5—C6120.35 (17)N4—C13—H13A109.1
C4—C5—H5119.8C12—C13—H13A109.1
C6—C5—H5119.8N4—C13—H13B109.1
C1—C6—C5118.56 (16)C12—C13—H13B109.1
C1—C6—C7122.80 (14)H13A—C13—H13B107.9
C5—C6—C7118.59 (15)N5—C14—N4112.54 (18)
N1—C7—N3110.00 (14)N5—C14—H14123.7
N1—C7—C6123.22 (14)N4—C14—H14123.7
N3—C7—C6126.76 (14)C16—C15—N5110.43 (19)
N2—C8—N3110.02 (15)C16—C15—H15124.8
N2—C8—C9125.15 (17)N5—C15—H15124.8
N3—C8—C9124.82 (17)C15—C16—N4106.56 (17)
C10—C9—C8113.94 (19)C15—C16—H16126.7
C10—C9—H9A108.8N4—C16—H16126.7
C8—C9—H9A108.8C7—N1—N2107.35 (13)
C10—C9—H9B108.8C8—N2—N1107.52 (13)
C8—C9—H9B108.8C8—N3—C7105.09 (14)
H9A—C9—H9B107.7C8—N3—C11126.52 (14)
C9—C10—H10A109.5C7—N3—C11128.05 (14)
C9—C10—H10B109.5C14—N4—C16105.73 (17)
H10A—C10—H10B109.5C14—N4—C13127.14 (17)
C9—C10—H10C109.5C16—N4—C13127.00 (17)
H10A—C10—H10C109.5C14—N5—C15104.73 (18)
H10B—C10—H10C109.5H1A—O1—H1B108.4 (14)
N3—C11—C12114.56 (14)H2A—O2—H2B106.5 (14)
C6—C1—C2—C30.1 (3)C6—C7—N3—C8177.38 (15)
C1—C2—C3—C4−0.1 (3)N1—C7—N3—C11−174.85 (15)
C2—C3—C4—C5−0.3 (3)C6—C7—N3—C113.7 (3)
C3—C4—C5—C60.6 (3)C12—C11—N3—C884.7 (2)
C2—C1—C6—C50.2 (3)C12—C11—N3—C7−102.89 (19)
C2—C1—C6—C7177.55 (16)N5—C14—N4—C160.8 (2)
C4—C5—C6—C1−0.5 (2)N5—C14—N4—C13176.98 (15)
C4—C5—C6—C7−177.98 (15)C15—C16—N4—C14−0.6 (2)
C1—C6—C7—N1−137.55 (18)C15—C16—N4—C13−176.81 (16)
C5—C6—C7—N139.8 (2)C12—C13—N4—C14−67.3 (2)
C1—C6—C7—N344.1 (2)C12—C13—N4—C16108.1 (2)
C5—C6—C7—N3−138.58 (17)N4—C14—N5—C15−0.6 (2)
N2—C8—C9—C10−4.5 (3)C16—C15—N5—C140.2 (2)
N3—C8—C9—C10174.1 (2)C7—N3—C11—C12−102.89 (19)
N3—C11—C12—C13172.00 (15)C6—C7—N3—C113.7 (3)
C11—C12—C13—N4−58.7 (2)C6—C7—N3—C8177.38 (15)
N5—C15—C16—N40.3 (2)N1—C7—N3—C11−174.85 (15)
N3—C7—N1—N20.85 (18)N2—C8—N3—C11174.88 (15)
C6—C7—N1—N2−177.79 (14)C9—C8—N3—C11−3.9 (3)
N3—C8—N2—N1−0.6 (2)C5—C6—C7—N139.8 (2)
C9—C8—N2—N1178.21 (19)N1—C7—C6—C1−137.55 (18)
C7—N1—N2—C8−0.15 (19)N3—C7—C6—C144.1 (2)
N2—C8—N3—C71.09 (19)N2—C8—C9—C10−4.5 (3)
C9—C8—N3—C7−177.73 (19)C10—C9—C8—N3174.1 (2)
N2—C8—N3—C11174.88 (15)N4—C13—C12—C11−58.7 (2)
C9—C8—N3—C11−3.9 (3)N3—C11—C12—C13172.00 (15)
N1—C7—N3—C8−1.19 (18)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1A···O20.91 (1)1.98 (1)2.882 (3)172 (3)
O1—H1B···N2i0.90 (1)2.02 (1)2.913 (2)170 (3)
O2—H2A···N5ii0.91 (1)1.95 (1)2.859 (3)176 (2)
O2—H2B···O1iii0.91 (1)2.08 (2)2.949 (3)160 (3)

Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x−1, y, z; (iii) −x+1, y−1/2, −z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: JH2213).

References

  • Dolzhenko, A. V., Tan, G. K., Koh, L. L., Dolzhenko, A. V. & Chui, W. K. (2010). Acta Cryst. E66, o425. [PMC free article] [PubMed]
  • Enraf–Nonius (1994). CAD-4 EXPRESS Enraf–Nonius, Delft, The Netherlands.
  • Fair, C. K. (1990). MolEN Enraf–Nonius, Delft, The Netherlands.
  • Kalkan, H., Ustabaş, R., Sancak, K., Ünver, Y. & Vázquez-López, E. M. (2007). Acta Cryst. E63, o2449–o2451.
  • Köysal, Y., Işık, Ş., Sancak, K. & Ünver, Y. (2006). Acta Cryst. E62, o3907–o3909.
  • North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359.
  • Ocak Ískeleli, N., Işık, S., Sancak, K., Şaşmaz, S., Ünver, Y. & Er, M. (2005). Acta Cryst. C61, o363–o365. [PubMed]
  • Rizzoli, C., Marku, E. & Greci, L. (2009). Acta Cryst. E65, o663. [PMC free article] [PubMed]
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Thenmozhi, M., Kavitha, T., Reddy, B. P., Vijayakumar, V. & Ponnuswamy, M. N. (2010). Acta Cryst. E66, o558. [PMC free article] [PubMed]
  • Ünver, Y., Köysal, Y., Tanak, H., Ünlüer, D. & Işık, Ş. (2010). Acta Cryst. E66, o1294. [PMC free article] [PubMed]
  • Ünver, Y., Sancak, K., Tanak, H., Değirmencioğlu, I., Düğdü, E., Er, M. & Işık, Ş. (2009). J. Mol. Struct.936, 46–55.
  • Zsolnai, L. (1997). ZORTEP University of Heidelberg, Germany.

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