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Acta Crystallogr Sect E Struct Rep Online. 2008 August 1; 64(Pt 8): o1590–o1591.
Published online 2008 July 26. doi:  10.1107/S1600536808022794
PMCID: PMC2962189

4-Amino-3-{1-[4-(2-methyl­prop­yl)phen­yl]eth­yl}-1H-1,2,4-triazole-5(4H)-thione

Abstract

In the title triazole compound, C14H20N4S, the dihedral angle between the triazole and benzene rings is 83.29 (11)°. The methine H atom and two methyl groups of the isobutyl group are disordered over two sites with occupancies of 0.684 (9) and 0.316 (9). In the crystal structure, N—H(...)S hydrogen bonds link the mol­ecules into chains running along the b axis. These chains are cross-linked into a two-dimensional network parallel to the ab plane by C—H(...)S hydrogen bonds.

Related literature

For bond-length data, see: Allen et al. (1987 [triangle]). For related structures, see: Fun et al. (2008a [triangle],b [triangle],c [triangle]). For the activities and applications of 1,2,4-triazole derivatives, see: Bhat et al. (2004 [triangle]); Holla et al. (2002 [triangle]); Karthikeyan et al. (2007 [triangle]); Raafat et al. (2006 [triangle]); Wei et al. (2007 [triangle]).

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Object name is e-64-o1590-scheme1.jpg

Experimental

Crystal data

  • C14H20N4S
  • M r = 276.41
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o1590-efi1.jpg
  • a = 5.9720 (3) Å
  • b = 8.5153 (5) Å
  • c = 14.8271 (6) Å
  • β = 97.223 (3)°
  • V = 748.03 (7) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.21 mm−1
  • T = 100.0 (1) K
  • 0.58 × 0.39 × 0.13 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.888, T max = 0.974
  • 10373 measured reflections
  • 3612 independent reflections
  • 3295 reflections with I > 2σ(I)
  • R int = 0.029

Refinement

  • R[F 2 > 2σ(F 2)] = 0.045
  • wR(F 2) = 0.119
  • S = 1.07
  • 3612 reflections
  • 199 parameters
  • 29 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.74 e Å−3
  • Δρmin = −0.54 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 1293 Friedel pairs
  • Flack parameter: 0.05 (9)

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 [triangle]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808022794/ci2633sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808022794/ci2633Isup2.hkl

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

Acknowledgments

KVS and BK are grateful to the Kerala State Council for Science Technology and the Environment, Thiruvanan­thapuram, for financial assistance. The authors also thank Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

supplementary crystallographic information

Comment

In recent decades, a large number of reports concerning 4-amino-1,2,4-triazol-3-thiones have appeared owing to a wide variety of their biological activity. The 1,2,4-triazole nucleus has been incorporated into a wide variety of therapeutically interesting drug candidates, including H1/H2 histamine receptor blockers, cholinesterase-active agents, CNS stimulants, antianxiety agents, and sedatives (Bhat et al., 2004). The amino and thione groups are ready-made nucleophilic centers for the synthesis of condensed nitrogen and sulfur heterocyclic rings, e.g., triazolothiadiazoles, triazolothiadiazines and triazolothiadiazepines (Raafat et al., 2006). Substituted derivatives of triazole possess comprehensive bioactivities such as antimicrobial, anti-inflammatory, analgesic, antitumorial, antihypertensive, anticonvulsant and antiviral activities (Wei et al., 2007). The broad biological activities that the 1,2,4-triazoles shown may be due to the presence of the >N—C—S moiety (Holla et al., 2002). Due to the progress that occurs in dealing with the chemistry of substituted 4-amino-1,2,4-triazole-3-thiones as well as their biological activity, we report here the crystal structure of the title triazole compound.

The bond distances and angles in the title molecule (Fig .1) have normal values (Allen et al., 1987) and are comparable with those observed in related structures (Fun et al., 2008a,b,c). The triazole ring (C1/C2/N1-N3) is planar to within ±0.004 Å. The chiral carbon atom C3 is in a distorted tetrahedral configuration. The dihedral angle between the triazole and benzene (C4-C9) rings is 83.29 (11)°. The 2-methylpropyl group is disordered over two sites. The orientation of this group with respect to the benzene ring can be indicated by the torsion angles C7–C10–C11–C12 = 167.1 (4)° and C7–C10–C11–C13 = -53.8 (5)° [C7–C10–C11–C12A = -162.4 (5)° and C7–C10–C11–C13A = 58.6 (10)° for the minor component].

In the crystal packing, the molecules are linked into chains along the b axis by N—H···S hydrogen bonds (Fig. 2). These chains are cross-linked into a two dimensional network parallel to the ab plane by C—H···S hydrogen bonds (Table 1).

Experimental

The title compound was prepared by following the literature procedure (Karthikeyan et al., 2007). The solid product obtained was collected by filtration, washed with ethanol and dried. Colourless single crystals suitable for X-ray analysis were obtained from an ethanol solution by slow evaporation (yield 61%; m.p. 423–424 K).

Refinement

The methylpropyl group is disordered over two orientations with refined occupancies of 0.685 (8) and 0.315 (8). During refinement, bond distances involving C12, C13, C12A and C13A atoms were restrained to 1.530 (7) Å, and their displacement parameters were restrained to an approximate isotropic behaviour. H atoms attached to N4 were located in a difference map and refined freely. The remaining H atoms were placed in calculated positions [N-H = 0.88 Å, C-H = 0.95-1.00 Å] and refined using a riding-model with Uiso(H) = 1.5Ueq(Cmethyl) and 1.2Ueq(C,N).

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Both disorder components are shown.
Fig. 2.
The packing diagram of the title compound, viewed along the c axis. Only the major disorder component is shown. Hydrogen bonds are shown as dashed lines.

Crystal data

C14H20N4SF000 = 296
Mr = 276.41Dx = 1.227 Mg m3
Monoclinic, P21Melting point = 423–424 K
Hall symbol: P 2ybMo Kα radiation λ = 0.71073 Å
a = 5.9720 (3) ÅCell parameters from 3612 reflections
b = 8.5153 (5) Åθ = 2.8–30.0º
c = 14.8271 (6) ŵ = 0.21 mm1
β = 97.223 (3)ºT = 100.0 (1) K
V = 748.03 (7) Å3Block, colourless
Z = 20.58 × 0.39 × 0.13 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer3612 independent reflections
Radiation source: fine-focus sealed tube3295 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.029
Detector resolution: 8.33 pixels mm-1θmax = 30.0º
T = 100.0(1) Kθmin = 2.8º
ω scansh = −8→8
Absorption correction: multi-scan(SADABS; Bruker, 2005)k = −11→11
Tmin = 0.888, Tmax = 0.974l = −20→20
10373 measured reflections

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.046  w = 1/[σ2(Fo2) + (0.0623P)2 + 0.2342P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.119(Δ/σ)max = 0.001
S = 1.07Δρmax = 0.74 e Å3
3612 reflectionsΔρmin = −0.54 e Å3
199 parametersExtinction correction: none
29 restraintsAbsolute structure: Flack (1983), 1293 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.05 (9)
Secondary atom site location: difference Fourier map

Special details

Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.
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*/UeqOcc. (<1)
S10.52913 (8)0.63928 (8)0.56907 (3)0.02823 (14)
N10.3013 (3)0.7737 (3)0.41731 (11)0.0254 (4)
H10.38800.85760.41940.030*
N20.1200 (3)0.7497 (3)0.35093 (12)0.0268 (4)
N30.1622 (3)0.5540 (3)0.44853 (12)0.0255 (4)
N40.1075 (4)0.4156 (3)0.49036 (14)0.0304 (5)
H4A0.205 (5)0.349 (4)0.477 (2)0.036 (8)*
H4B0.120 (6)0.435 (5)0.551 (2)0.050 (9)*
C10.3316 (3)0.6572 (3)0.47770 (12)0.0236 (4)
C20.0397 (3)0.6138 (3)0.37174 (13)0.0242 (5)
C3−0.1391 (4)0.5226 (3)0.31435 (13)0.0262 (5)
H3−0.24640.47900.35460.031*
C4−0.0251 (3)0.3868 (3)0.27194 (13)0.0245 (4)
C5−0.1039 (4)0.2344 (3)0.27769 (15)0.0304 (5)
H5−0.23420.21540.30680.037*
C60.0035 (4)0.1101 (3)0.24192 (15)0.0299 (5)
H6−0.05380.00680.24680.036*
C70.1950 (3)0.1335 (4)0.19865 (12)0.0275 (4)
C80.2718 (4)0.2844 (4)0.19190 (16)0.0324 (6)
H80.40090.30310.16200.039*
C90.1650 (4)0.4104 (3)0.22788 (15)0.0291 (5)
H90.22200.51370.22240.035*
C100.3109 (4)−0.0036 (4)0.15975 (16)0.0368 (6)
H10A0.2910−0.09800.19690.044*
H10B0.47470.01860.16430.044*
C110.2221 (5)−0.0394 (6)0.0603 (2)0.0730 (14)
H11A0.24580.06240.02930.088*0.685 (8)
H11B0.0645−0.05620.06390.088*0.315 (8)
C120.3694 (11)−0.1501 (9)0.0159 (4)0.0661 (18)0.685 (8)
H12A0.3053−0.1668−0.04750.099*0.685 (8)
H12B0.3782−0.25070.04830.099*0.685 (8)
H12C0.5210−0.10530.01790.099*0.685 (8)
C13−0.0227 (7)−0.0626 (7)0.0405 (3)0.0514 (15)0.685 (8)
H13A−0.0626−0.0822−0.02470.077*0.685 (8)
H13B−0.10100.03180.05780.077*0.685 (8)
H13C−0.0679−0.15280.07500.077*0.685 (8)
C12A0.309 (2)−0.2128 (11)0.0475 (8)0.057 (3)0.315 (8)
H12D0.2612−0.2475−0.01490.085*0.315 (8)
H12E0.2456−0.28310.09010.085*0.315 (8)
H12F0.4742−0.21490.05950.085*0.315 (8)
C13A0.220 (3)0.0688 (16)−0.0169 (8)0.096 (6)0.315 (8)
H13D0.16480.1717−0.00020.144*0.315 (8)
H13E0.12140.0271−0.06910.144*0.315 (8)
H13F0.37400.0797−0.03290.144*0.315 (8)
C14−0.2708 (4)0.6302 (4)0.24338 (15)0.0321 (5)
H14A−0.34040.71560.27430.048*
H14B−0.38860.56930.20690.048*
H14C−0.16740.67420.20370.048*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0253 (2)0.0327 (3)0.0260 (2)0.0030 (3)0.00040 (16)−0.0015 (2)
N10.0251 (8)0.0242 (11)0.0263 (8)0.0010 (8)0.0010 (6)−0.0027 (7)
N20.0252 (9)0.0283 (11)0.0260 (8)0.0019 (9)0.0003 (6)−0.0031 (7)
N30.0222 (8)0.0301 (11)0.0246 (8)0.0005 (8)0.0050 (6)0.0010 (7)
N40.0269 (9)0.0345 (12)0.0308 (9)−0.0024 (10)0.0079 (7)0.0085 (9)
C10.0222 (8)0.0256 (13)0.0239 (8)0.0026 (10)0.0068 (6)−0.0016 (8)
C20.0227 (8)0.0280 (14)0.0224 (8)0.0040 (10)0.0045 (6)0.0018 (8)
C30.0204 (9)0.0301 (13)0.0286 (9)−0.0016 (10)0.0044 (7)0.0001 (9)
C40.0204 (9)0.0295 (12)0.0227 (8)−0.0003 (10)−0.0001 (7)0.0000 (8)
C50.0283 (11)0.0333 (14)0.0312 (10)−0.0001 (11)0.0095 (8)0.0065 (9)
C60.0326 (10)0.0269 (14)0.0302 (9)−0.0007 (11)0.0040 (8)0.0039 (9)
C70.0235 (8)0.0358 (12)0.0220 (7)0.0045 (13)−0.0018 (6)−0.0020 (11)
C80.0244 (10)0.0444 (16)0.0288 (10)−0.0076 (11)0.0054 (8)−0.0084 (10)
C90.0263 (10)0.0313 (13)0.0304 (10)−0.0074 (11)0.0062 (8)−0.0041 (9)
C100.0319 (12)0.0444 (17)0.0325 (11)0.0092 (13)−0.0017 (9)−0.0107 (11)
C110.0469 (17)0.120 (4)0.0501 (17)0.028 (2)−0.0016 (13)−0.044 (2)
C120.072 (4)0.077 (4)0.053 (3)0.008 (3)0.028 (3)−0.029 (3)
C130.047 (2)0.071 (4)0.0333 (18)−0.003 (2)−0.0046 (16)−0.018 (2)
C12A0.040 (5)0.092 (8)0.040 (5)−0.005 (5)0.006 (4)−0.021 (5)
C13A0.086 (8)0.107 (10)0.090 (8)0.008 (7)−0.008 (6)−0.040 (7)
C140.0249 (9)0.0328 (13)0.0368 (10)−0.0003 (13)−0.0027 (7)0.0012 (11)

Geometric parameters (Å, °)

S1—C11.688 (2)C10—C111.533 (4)
N1—C11.334 (3)C10—H10A0.99
N1—N21.384 (2)C10—H10B0.99
N1—H10.8800C11—C131.468 (4)
N2—C21.304 (3)C11—C13A1.468 (7)
N3—C11.368 (3)C11—C121.497 (5)
N3—C21.372 (3)C11—C12A1.584 (7)
N3—N41.390 (3)C11—H11A1.00
N4—H4A0.85 (4)C11—H11B0.96
N4—H4B0.91 (3)C12—H12A0.98
C2—C31.496 (3)C12—H12B0.98
C3—C41.518 (3)C12—H12C0.98
C3—C141.535 (3)C13—H13A0.98
C3—H31.00C13—H13B0.98
C4—C51.386 (4)C13—H13C0.98
C4—C91.394 (3)C12A—H12D0.98
C5—C61.378 (4)C12A—H12E0.98
C5—H50.95C12A—H12F0.98
C6—C71.394 (3)C13A—H13D0.98
C6—H60.95C13A—H13E0.98
C7—C81.372 (4)C13A—H13F0.98
C7—C101.508 (4)C14—H14A0.98
C8—C91.389 (4)C14—H14B0.98
C8—H80.95C14—H14C0.98
C9—H90.95
C1—N1—N2113.3 (2)C13—C11—C10115.8 (3)
C1—N1—H1123.4C13A—C11—C10126.3 (7)
N2—N1—H1123.4C12—C11—C10113.4 (3)
C2—N2—N1103.96 (18)C13—C11—C12A100.6 (5)
C1—N3—C2108.67 (19)C13A—C11—C12A117.5 (8)
C1—N3—N4127.56 (18)C10—C11—C12A102.8 (5)
C2—N3—N4123.66 (19)C13—C11—H11A102.6
N3—N4—H4A105 (2)C12—C11—H11A102.6
N3—N4—H4B107 (3)C10—C11—H11A102.6
H4A—N4—H4B112 (3)C12A—C11—H11A133.3
N1—C1—N3103.48 (17)C13A—C11—H11B103.0
N1—C1—S1128.94 (19)C12—C11—H11B124.4
N3—C1—S1127.58 (18)C10—C11—H11B101.5
N2—C2—N3110.60 (19)C12A—C11—H11B101.9
N2—C2—C3125.67 (19)H11A—C11—H11B110.5
N3—C2—C3123.2 (2)C11—C12—H12A109.5
C2—C3—C4107.83 (17)C11—C12—H12B109.5
C2—C3—C14110.3 (2)H12A—C12—H12B109.5
C4—C3—C14112.86 (18)C11—C12—H12C109.5
C2—C3—H3108.6H12A—C12—H12C109.5
C4—C3—H3108.6H12B—C12—H12C109.5
C14—C3—H3108.6C11—C13—H13A109.5
C5—C4—C9117.8 (2)H11B—C13—H13A133.0
C5—C4—C3120.96 (19)C11—C13—H13B109.5
C9—C4—C3121.2 (2)H11B—C13—H13B100.7
C6—C5—C4121.2 (2)H13A—C13—H13B109.5
C6—C5—H5119.4C11—C13—H13C109.5
C4—C5—H5119.4H11B—C13—H13C92.6
C5—C6—C7121.0 (3)H13A—C13—H13C109.5
C5—C6—H6119.5H13B—C13—H13C109.5
C7—C6—H6119.5C11—C12A—H12D109.5
C8—C7—C6117.9 (3)C11—C12A—H12E109.5
C8—C7—C10121.6 (2)H12D—C12A—H12E109.5
C6—C7—C10120.5 (3)C11—C12A—H12F109.5
C7—C8—C9121.4 (2)H12D—C12A—H12F109.5
C7—C8—H8119.3H12E—C12A—H12F109.5
C9—C8—H8119.3C11—C13A—H13D109.5
C8—C9—C4120.6 (2)C11—C13A—H13E109.5
C8—C9—H9119.7H13D—C13A—H13E109.5
C4—C9—H9119.7C11—C13A—H13F109.5
C7—C10—C11113.7 (2)H13D—C13A—H13F109.5
C7—C10—H10A108.8H13E—C13A—H13F109.5
C11—C10—H10A108.8C3—C14—H14A109.5
C7—C10—H10B108.8C3—C14—H14B109.5
C11—C10—H10B108.8H14A—C14—H14B109.5
H10A—C10—H10B107.7C3—C14—H14C109.5
C13—C11—C13A91.1 (8)H14A—C14—H14C109.5
C13—C11—C12116.9 (4)H14B—C14—H14C109.5
C13A—C11—C1290.0 (8)
C1—N1—N2—C2−0.4 (2)C2—C3—C4—C9−49.2 (3)
N2—N1—C1—N30.1 (2)C14—C3—C4—C972.9 (3)
N2—N1—C1—S1−179.58 (16)C9—C4—C5—C60.7 (3)
C2—N3—C1—N10.3 (2)C3—C4—C5—C6−177.8 (2)
N4—N3—C1—N1−175.8 (2)C4—C5—C6—C7−0.1 (3)
C2—N3—C1—S1179.98 (16)C5—C6—C7—C8−0.7 (3)
N4—N3—C1—S13.8 (3)C5—C6—C7—C10−180.0 (2)
N1—N2—C2—N30.6 (2)C6—C7—C8—C90.8 (3)
N1—N2—C2—C3−171.3 (2)C10—C7—C8—C9−179.9 (2)
C1—N3—C2—N2−0.6 (2)C7—C8—C9—C4−0.2 (4)
N4—N3—C2—N2175.7 (2)C5—C4—C9—C8−0.6 (3)
C1—N3—C2—C3171.53 (18)C3—C4—C9—C8177.9 (2)
N4—N3—C2—C3−12.1 (3)C8—C7—C10—C11−88.8 (3)
N2—C2—C3—C4105.2 (3)C6—C7—C10—C1190.4 (3)
N3—C2—C3—C4−65.8 (2)C7—C10—C11—C13−53.8 (5)
N2—C2—C3—C14−18.5 (3)C7—C10—C11—C13A58.6 (10)
N3—C2—C3—C14170.53 (19)C7—C10—C11—C12167.1 (4)
C2—C3—C4—C5129.3 (2)C7—C10—C11—C12A−162.4 (5)
C14—C3—C4—C5−108.6 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1···S1i0.882.453.272 (3)155
N4—H4A···S1ii0.85 (3)2.54 (3)3.392 (3)176 (3)
C5—H5···S1iii0.952.783.704 (2)165

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2633).

References

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