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ISSN: 2056-9890
Volume 65| Part 5| May 2009| Page o1116

7-(2,4-Di­chloro­phen­yl)-2-methyl­sulfanyl­pyrazolo[1,5-a]pyrimidine-3-carbo­nitrile

aCollege of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, People's Republic of China
*Correspondence e-mail: wenlirong@qust.edu.cn

(Received 2 April 2009; accepted 21 April 2009; online 25 April 2009)

In the mol­ecule of the title compound, C14H8Cl2N4S, all the ring atoms in the pyrazolopyrimidine system are almost coplanar, the largest deviation from the mean plane being 0.027 (2) Å for a C atom. The conformation of the methyl­sulfanyl group is anti­periplanar, with a torsion angle of −176.7 (2)°. A weak inter­molecular C—H⋯N hydrogen bond and a Cl⋯N halogen bond [Cl⋯N = 3.196 (5) Å] with a nearly linear N⋯Cl—C angle [174.2 (1)°] link the mol­ecules into a two-dimensional assembly. Face-to-face ππ stacking, with a centroid–centroid separation of 3.557 (2) Å and an angle of 7.1 (1)° between the two planes, completes the inter­molecular inter­actions in the solid state.

Related literature

For the biological activity of pyrazolo[1,5-a]pyrimidine derivatives, see: Li et al. (1995[Li, J. J., Anderson, D., Burton, E. G. & Cogburn, J. N. (1995). J. Med. Chem. 38, 4570-4578.]). For applications of enamino­nes, see: El-Taweei et al. (2001[El-Taweei, F. M. A. A. & Elangdi, M. H. (2001). J. Heterocycl. Chem. 38, 981-984.]); Hernandez et al. (2003[Hernandez, S., Sanmantin, R., Tellitu, I. & Dominguez, E. (2003). Org. Lett. 5, 1095-1098.]); Olivera et al. (2000[Olivera, R., SanMartin, R., Tellitu, I. & Dominguez, E. (2000). Tetrahedron Lett. 41, 4353-4356.]). 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 Cl⋯N halogen bonds, see: Chu, et al. (2001[Chu, Q., Wang, Z., Huang, Q., Yan, C. & Zhu, S. (2001). J. Am. Chem. Soc. 123, 11069-11070.]); Lommerse et al. (1996[Lommerse, J. P. M., Stone, A. J., Taylor, R. & Allen, F. H. (1996). J. Am. Chem. Soc. 118, 3108-3116.]); Ramasubbu et al. (1986[Ramasubbu, N., Parthasarathy, R. & Murray-Rust, P. (1986). J. Am. Chem. Soc. 108, 4308-4314.]).

[Scheme 1]

Experimental

Crystal data
  • C14H8Cl2N4S

  • Mr = 335.20

  • Monoclinic, P 21 /n

  • a = 8.230 (2) Å

  • b = 14.656 (4) Å

  • c = 12.667 (4) Å

  • β = 108.460 (5)°

  • V = 1449.3 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.59 mm−1

  • T = 293 K

  • 0.32 × 0.26 × 0.22 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS, University of Göttingen, Germany.]) Tmin = 0.814, Tmax = 0.879

  • 8252 measured reflections

  • 2965 independent reflections

  • 2181 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.095

  • S = 1.04

  • 2965 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8⋯N4i 0.93 2.61 3.474 (3) 154
Symmetry code: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). 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

Pyrazolo[1,5-a]pyrimidine derivatives have been reported to show various biological activities such as antibacterial, insulin releasing, anti-inflammatory activities (Li et al., 1995). Enaminones have been widely used as building blocks in the synthesis of pyrazolo[1,5-a]pyrimidine derivatives (El-Taweei et al., 2001; Hernandez et al., 2003; Olivera et al., 2000). We report here the crystal structure of title compound (Fig.1), which was synthesized by reaction of 1-(2,4-dichlorophenyl)-3-dimethylamino-2-en-1-one and 3-methylsulfanyl-4-cyano-5-amino-1H-pyrazole in the presence of acetic acid.

The bond lengths and angles in this compound are within normal ranges (Allen, 2002). All the ring atoms in the pyrazolopyrimidine moiety are almost coplanar, the largest deviation from the mean plane being 0.027 (2)Å for atom C10. The dihedral angle between the pyrazolopyrimidine moiety and the benzene ring is 54.9 (5)°. The conformation of the methylsulfanyl moiety is antiperiplanar with a torsion angle C11—C12—S1—C13 of -176.7 (2)°.

In the crystal structure of the title compound, there are a weak intermolecular hydrogen bond of one phenyl hydrogen atom towards the nitrile N atom (C8—H8···N4, Table 1) and a nitrogen-chlorine donor-acceptor interaction (Chu, et al., 2001; Lommerse et al., 1996; Ramasubbu, et al., 1986) between the pyrimidinyl N atom and one of the chlorine atoms. The distance between Cl2 and N3 is 3.196 (5) Å which is definitively shorter than the sum of the corresponding van der Waals radii of Cl (1.75 Å) and N (1.55 Å). Moreover, this contact of N3 with Cl2 is nearly "head on" with N approaching Cl along the backside of C3—Cl2 with the N3···Cl2—C3 angle approximately linear 174.2 (1)° [symmetry code: -3/2 + x, 1/2 - y, -1/2 + z] (Fig. 2). These interactions loosly link the molecules into a two-dimensional assembly (Fig. 3). Face-to-face π-π stacking between the phenyl ring (C1—C6) and the pyrazol ring (C10—C12/N1/N2) in another molecule at 1/2+x, 3/2-y, 1/2+z complete the intermolecular interactions in the solid state. The centroid to centroid separation is 3.557 (2) Å and the angle between the two planes is 7.1 (1)°.

Related literature top

For the biological activity of pyrazolo[1,5-a]pyrimidine derivatives, see: Li et al. (1995). For applications of enaminones, see: El-Taweei et al. (2001); Hernandez et al. (2003); Olivera et al. (2000). For bond lengths and angles, see: Allen (2002) [Check reference - this gives a description of the CSD]. For Cl···N halogen bonds, see: Chu, et al. (2001); Lommerse et al. (1996); Ramasubbu et al. (1986).

Experimental top

A mixture of 1-(2,4-dichlorophenyl)-3-dimethylamino-2-en-1-one (2 mmol) and 3-methylsulfanyl-4-cyano-5-amino-1H-pyrazole (2 mmol) in glacial acetic acid (15 ml) was stirred for 12 h at room temperature. Then the mixture was evaporated by rotary evaporation to remove the acetic acid, and recrystallized from a mixture of EtOH and DMF. Yield: 77%. (m.p. 475 K).

Refinement top

All H atoms were placed in calculated positions, with C—H = 0.93 or 0.96 Å, and included in the final cycles of the refinement using a riding model, with Uiso(H) set to 1.2 Ueq(C) for CH, and 1.5 Ueq(C) for CH3.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); 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. View of the title compound with 35% probability ellipsoids.
[Figure 2] Fig. 2. The molecular packing of the title compound viewed along the a axis. Dashed lines indicate the hydrogen bonds and N···Cl short contacts.
[Figure 3] Fig. 3. Diagram of two-dimensional structure linked by the hydrogen bonds and N···Cl short contacts.
7-(2,4-Dichlorophenyl)-2-methylsulfanylpyrazolo[1,5-a]pyrimidine- 3-carbonitrile top
Crystal data top
C14H8Cl2N4SF(000) = 680
Mr = 335.20Dx = 1.536 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 970 reflections
a = 8.230 (2) Åθ = 2.8–26.3°
b = 14.656 (4) ŵ = 0.59 mm1
c = 12.667 (4) ÅT = 293 K
β = 108.460 (5)°Prism, colorless
V = 1449.3 (7) Å30.32 × 0.26 × 0.22 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer
2965 independent reflections
Radiation source: fine-focus sealed tube2181 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
ϕ and ω scansθmax = 26.4°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 610
Tmin = 0.814, Tmax = 0.879k = 1618
8252 measured reflectionsl = 1514
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0395P)2 + 0.5056P]
where P = (Fo2 + 2Fc2)/3
2965 reflections(Δ/σ)max = 0.001
191 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C14H8Cl2N4SV = 1449.3 (7) Å3
Mr = 335.20Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.230 (2) ŵ = 0.59 mm1
b = 14.656 (4) ÅT = 293 K
c = 12.667 (4) Å0.32 × 0.26 × 0.22 mm
β = 108.460 (5)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2965 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2181 reflections with I > 2σ(I)
Tmin = 0.814, Tmax = 0.879Rint = 0.032
8252 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.095H-atom parameters constrained
S = 1.04Δρmax = 0.22 e Å3
2965 reflectionsΔρmin = 0.29 e Å3
191 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
S10.07522 (9)1.04589 (4)0.33961 (6)0.0515 (2)
Cl10.27654 (9)0.56767 (4)0.47097 (6)0.0587 (2)
Cl20.81796 (7)0.72025 (5)0.77238 (6)0.0570 (2)
N10.1176 (2)0.88388 (12)0.44665 (15)0.0337 (4)
N20.0148 (2)0.81205 (12)0.45471 (14)0.0304 (4)
N40.4254 (3)0.99138 (17)0.2170 (2)0.0694 (8)
C10.3585 (3)0.65420 (15)0.56647 (18)0.0351 (5)
C20.5304 (3)0.65097 (16)0.62770 (19)0.0399 (6)
H20.59820.60250.61930.048*
C30.6000 (3)0.72040 (16)0.70121 (19)0.0373 (5)
C40.4996 (3)0.79158 (16)0.71666 (19)0.0385 (5)
H40.54680.83730.76810.046*
C50.3289 (3)0.79383 (16)0.65490 (19)0.0383 (5)
H50.26160.84200.66480.046*
C60.2541 (3)0.72596 (14)0.57789 (18)0.0317 (5)
C70.0708 (3)0.73292 (15)0.51216 (18)0.0335 (5)
C80.0531 (3)0.66876 (16)0.5045 (2)0.0437 (6)
H80.02430.61320.54110.052*
C90.2230 (3)0.68669 (18)0.4416 (2)0.0479 (6)
H90.30360.64120.43760.057*
N30.2771 (2)0.76324 (14)0.38782 (17)0.0427 (5)
C100.1555 (3)0.82588 (15)0.39444 (18)0.0336 (5)
C110.1611 (3)0.91130 (15)0.34518 (18)0.0352 (5)
C120.0087 (3)0.94280 (15)0.38006 (18)0.0342 (5)
C130.3024 (4)1.0381 (2)0.4068 (3)0.0697 (9)
H13A0.32491.02290.48380.105*
H13B0.35471.09570.40120.105*
H13C0.34890.99160.37140.105*
C140.3084 (3)0.95536 (16)0.2741 (2)0.0429 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0594 (4)0.0374 (4)0.0588 (4)0.0004 (3)0.0206 (3)0.0114 (3)
Cl10.0602 (4)0.0408 (4)0.0615 (4)0.0086 (3)0.0002 (3)0.0164 (3)
Cl20.0290 (3)0.0678 (5)0.0654 (5)0.0002 (3)0.0025 (3)0.0056 (4)
N10.0313 (10)0.0320 (10)0.0379 (11)0.0008 (8)0.0110 (8)0.0017 (8)
N20.0266 (9)0.0312 (10)0.0319 (10)0.0020 (7)0.0069 (7)0.0012 (8)
N40.0641 (15)0.0544 (15)0.0648 (16)0.0238 (12)0.0150 (13)0.0040 (12)
C10.0396 (13)0.0294 (11)0.0335 (12)0.0021 (10)0.0075 (10)0.0003 (10)
C20.0361 (13)0.0379 (13)0.0445 (14)0.0101 (10)0.0113 (11)0.0052 (11)
C30.0276 (11)0.0421 (13)0.0400 (13)0.0003 (10)0.0075 (10)0.0083 (11)
C40.0385 (13)0.0377 (13)0.0347 (12)0.0040 (10)0.0049 (10)0.0013 (10)
C50.0391 (13)0.0346 (13)0.0388 (13)0.0072 (10)0.0089 (10)0.0002 (10)
C60.0309 (11)0.0302 (11)0.0312 (11)0.0028 (9)0.0056 (9)0.0034 (9)
C70.0338 (12)0.0325 (12)0.0323 (12)0.0048 (9)0.0079 (10)0.0029 (9)
C80.0417 (14)0.0374 (14)0.0475 (15)0.0015 (11)0.0075 (11)0.0110 (11)
C90.0385 (14)0.0461 (15)0.0550 (16)0.0102 (11)0.0089 (12)0.0053 (12)
N30.0289 (10)0.0456 (12)0.0497 (12)0.0016 (9)0.0070 (9)0.0027 (10)
C100.0280 (11)0.0383 (13)0.0327 (12)0.0045 (10)0.0069 (9)0.0005 (10)
C110.0353 (12)0.0347 (12)0.0319 (12)0.0072 (10)0.0054 (9)0.0002 (10)
C120.0391 (12)0.0320 (12)0.0319 (12)0.0021 (10)0.0117 (10)0.0001 (10)
C130.0535 (17)0.0595 (19)0.104 (3)0.0107 (14)0.0367 (17)0.0076 (18)
C140.0450 (14)0.0362 (13)0.0393 (13)0.0077 (11)0.0016 (11)0.0040 (11)
Geometric parameters (Å, º) top
S1—C121.739 (2)C5—C61.393 (3)
S1—C131.796 (3)C5—H50.9300
Cl1—C11.735 (2)C6—C71.478 (3)
Cl2—C31.734 (2)C7—C81.368 (3)
N1—C121.335 (3)C8—C91.398 (3)
N1—N21.375 (2)C8—H80.9300
N2—C71.369 (3)C9—N31.315 (3)
N2—C101.383 (3)C9—H90.9300
N4—C141.135 (3)N3—C101.341 (3)
C1—C21.382 (3)C10—C111.393 (3)
C1—C61.394 (3)C11—C121.404 (3)
C2—C31.376 (3)C11—C141.416 (3)
C2—H20.9300C13—H13A0.9600
C3—C41.383 (3)C13—H13B0.9600
C4—C51.375 (3)C13—H13C0.9600
C4—H40.9300
C12—S1—C13100.53 (12)N2—C7—C6118.02 (18)
C12—N1—N2103.65 (17)C7—C8—C9120.0 (2)
C7—N2—N1125.20 (17)C7—C8—H8120.0
C7—N2—C10121.97 (18)C9—C8—H8120.0
N1—N2—C10112.79 (17)N3—C9—C8124.7 (2)
C2—C1—C6121.5 (2)N3—C9—H9117.6
C2—C1—Cl1117.98 (17)C8—C9—H9117.6
C6—C1—Cl1120.48 (17)C9—N3—C10115.34 (19)
C3—C2—C1119.2 (2)N3—C10—N2122.7 (2)
C3—C2—H2120.4N3—C10—C11132.0 (2)
C1—C2—H2120.4N2—C10—C11105.25 (18)
C2—C3—C4120.9 (2)C10—C11—C12105.43 (18)
C2—C3—Cl2119.44 (18)C10—C11—C14126.5 (2)
C4—C3—Cl2119.59 (18)C12—C11—C14128.1 (2)
C5—C4—C3119.1 (2)N1—C12—C11112.9 (2)
C5—C4—H4120.4N1—C12—S1122.49 (17)
C3—C4—H4120.4C11—C12—S1124.61 (17)
C4—C5—C6121.8 (2)S1—C13—H13A109.5
C4—C5—H5119.1S1—C13—H13B109.5
C6—C5—H5119.1H13A—C13—H13B109.5
C5—C6—C1117.5 (2)S1—C13—H13C109.5
C5—C6—C7119.43 (19)H13A—C13—H13C109.5
C1—C6—C7123.12 (19)H13B—C13—H13C109.5
C8—C7—N2115.24 (19)N4—C14—C11179.3 (3)
C8—C7—C6126.7 (2)
C12—N1—N2—C7177.7 (2)N2—C7—C8—C90.3 (3)
C12—N1—N2—C100.1 (2)C6—C7—C8—C9177.8 (2)
C6—C1—C2—C30.3 (3)C7—C8—C9—N30.8 (4)
Cl1—C1—C2—C3177.75 (18)C8—C9—N3—C101.3 (4)
C1—C2—C3—C41.8 (4)C9—N3—C10—N20.9 (3)
C1—C2—C3—Cl2176.31 (18)C9—N3—C10—C11176.2 (2)
C2—C3—C4—C51.9 (4)C7—N2—C10—N30.1 (3)
Cl2—C3—C4—C5176.16 (18)N1—N2—C10—N3177.8 (2)
C3—C4—C5—C60.6 (4)C7—N2—C10—C11177.85 (19)
C4—C5—C6—C10.9 (3)N1—N2—C10—C110.1 (2)
C4—C5—C6—C7178.7 (2)N3—C10—C11—C12177.4 (2)
C2—C1—C6—C51.0 (3)N2—C10—C11—C120.0 (2)
Cl1—C1—C6—C5179.02 (18)N3—C10—C11—C141.9 (4)
C2—C1—C6—C7178.6 (2)N2—C10—C11—C14179.4 (2)
Cl1—C1—C6—C70.6 (3)N2—N1—C12—C110.1 (2)
N1—N2—C7—C8177.0 (2)N2—N1—C12—S1178.37 (15)
C10—N2—C7—C80.7 (3)C10—C11—C12—N10.1 (3)
N1—N2—C7—C64.8 (3)C14—C11—C12—N1179.5 (2)
C10—N2—C7—C6177.55 (19)C10—C11—C12—S1178.38 (17)
C5—C6—C7—C8125.1 (3)C14—C11—C12—S11.0 (3)
C1—C6—C7—C855.3 (3)C13—S1—C12—N11.7 (2)
C5—C6—C7—N252.9 (3)C13—S1—C12—C11176.7 (2)
C1—C6—C7—N2126.7 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···N4i0.932.613.474 (3)154
Symmetry code: (i) x+1/2, y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H8Cl2N4S
Mr335.20
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)8.230 (2), 14.656 (4), 12.667 (4)
β (°) 108.460 (5)
V3)1449.3 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.59
Crystal size (mm)0.32 × 0.26 × 0.22
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.814, 0.879
No. of measured, independent and
observed [I > 2σ(I)] reflections
8252, 2965, 2181
Rint0.032
(sin θ/λ)max1)0.626
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.095, 1.04
No. of reflections2965
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.29

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8···N4i0.932.613.474 (3)154.2
Symmetry code: (i) x+1/2, y+3/2, z+1/2.
 

Acknowledgements

We thank the Natural Science Foundation of Shandong Province (No. Y2006B11) for financial support.

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
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Volume 65| Part 5| May 2009| Page o1116
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