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6-Amino-3,4-di­methyl-4-phenyl-2H,4H-pyrano[2,3-c]pyrazole-5-carbo­nitrile

aCentre for Bioinformatics, Pondicherry University, Puducherry 605 014, India, and bDepartment of Chemistry, Pondicherry University, Puducherry 605 014, India
*Correspondence e-mail: krishstrucbio@gmail.com

(Received 16 February 2011; accepted 11 March 2011; online 23 March 2011)

In the title compound, C15H14N4O, the pyrazole ring is aligned at 88.23 (4)° with respect to the aromatic ring and at 3.75 (4)° with respect to the pyran ring. In the crystal, N—H⋯N hydrogen bonds link adjacent mol­ecules into a linear chain motif. C—H⋯N inter­actions are also observed.

Related literature

For the synthesis, see: Vasuki & Kumaravel (2008[Vasuki, G. & Kumaravel, K. (2008). Tetrahedron Lett. 49, 5636-5638.]). For the use of related compounds in organic synthesis, see: Liang et al. (2009[Liang, F., Cheng, X., Liu, J. & Liu, Q. (2009). Chem. Commun. pp. 3636-3538.]). For related structures, see: Kannan et al. (2010[Kannan, M., Kumaravel, K., Vasuki, G. & Krishna, R. (2010). Acta Cryst. E66, o1242.]).

[Scheme 1]

Experimental

Crystal data
  • C15H14N4O

  • Mr = 266.3

  • Triclinic, [P \overline 1]

  • a = 6.682 (5) Å

  • b = 9.347 (5) Å

  • c = 11.078 (5) Å

  • α = 99.213 (5)°

  • β = 102.740 (5)°

  • γ = 97.767 (5)°

  • V = 655.6 (7) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 293 K

  • 0.22 × 0.20 × 0.16 mm

Data collection
  • Bruker APEXII Kappa CCD detector diffractometer

  • 18424 measured reflections

  • 4996 independent reflections

  • 3169 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.173

  • S = 0.99

  • 4996 reflections

  • 183 parameters

  • H-atom parameters constrained

  • Δρmax = 0.30 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
N3—H3A⋯N1i 0.86 2.27 3.129 (2) 173
N3—H3B⋯N4ii 0.86 2.26 3.087 (2) 160
C10—H10⋯N4iii 0.93 2.53 3.455 (3) 172
C14—H14A⋯N1iv 0.96 2.59 3.522 (3) 163
Symmetry codes: (i) -x, -y+1, -z+1; (ii) -x+1, -y+1, -z+2; (iii) -x+2, -y+2, -z+2; (iv) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The pyrano pyrazole derivatives are widely used as organic intermediates (Liang et al., 2009) and are well known for their biological contribution as ChK1 inhibitors. In view of the growing importance of the pyrano pyrazole derivatives, we have synthesized the title compound by Rapid four-component reactions in water (Vasuki & Kumaravel, 2008) and the single-crystal structure analysis was undertaken.

In the title compound, the attached benzyl ring makes the dihedral angle of 88.23 (4) ° and orient in (+)-syn-clinal conforamtion with pyrazole ring, whereas the fused pyrazole ring makes 3.75 (4) ° dihedral angle and orient by an (+)-syn-periplanar conformation with respect to the pyran ring (Fig. 1). The methyl group is attached to C6 atom of pyran with an angle of 109.29 (11) °. Two N—H···N and C—H···N intermolecular hydrogen bond interactions (Fig. 2) are observed for maintaining the crystal packing (Fig. 3), in which the N3—H···N4 intermolecular interaction are observed to form R22 (12) ring motifs (Fig. 4). The weak N—H···π intermolecular interaction is also observed for the stabilization of the crystal packing, with a bond distance of 3.382 (3) Å (Fig. 5).

Related literature top

For the synthesis, see: Vasuki & Kumaravel (2008). For the use of related compounds in organic synthesis, see: Liang et al. (2009). For related structures, see: Kannan et al. (2010).

Experimental top

The title compound was prepared by the successive addition of acetophenone 2 (0.240 g, 2 mmol), malononitrile (0.132 g, 2 mmol) and piperidine (5 mol%) to a stirred aqueous mixture of hydrazine hydrate 96% 1 (0.107 g, 2 mmol) and ethyl acetoacetate 2 (0.520 g, 2 mmol) at room temperature under an open atmosphere with vigorous stirring for 5–10 min. The precipitated solid was then filtered, followed by washing with water and then with a mixture of ethyl acetate/hexane (20:80). The product obtained was pure by TLC and 1H NMR spectroscopy. Nevertheless, the products were further purified by recrystallization from ethanol. Analysis calculated for 6-amino-3,4-dimethyl-4-phenyl-2H,4H-pyrano[2,3-c]pyrazole-5-carbonitrile showed that it has C15H14N4O.

Refinement top

All hydrogen atoms were placed in calculated positions, with N—H=0.86 and C—H=0.93–0.97 and included in the final cycles of refinement using a riding model with U(H) = 1.2 Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing the atom-numbering scheme and displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of (I), showing intermolecular hydrogen bonding interactions as dashed lines.
[Figure 3] Fig. 3. The crystal packing of Compound (I) viewed down the XO-axis, showing intermolecular hydrogen bonding interactions as dashed lines.
[Figure 4] Fig. 4. A view of R2 2 (12) ring motifs formed by N—H···N interaction between two molecules. The ring forming atoms are shown in ball and stick model and the Hydrogen bond are shown in green dashed lines.
[Figure 5] Fig. 5. The molecular interaction showing the weak N—H···pi interaction in Compound (I). Cg is a centroid of C8—C13 ring.
6-Amino-3,4-dimethyl-4-phenyl-2H,4H-pyrano[2,3-c]pyrazole- 5-carbonitrile top
Crystal data top
C15H14N4OZ = 2
Mr = 266.3F(000) = 280
Triclinic, P1Dx = 1.349 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71069 Å
a = 6.682 (5) ÅCell parameters from 4350 reflections
b = 9.347 (5) Åθ = 1.9–33.3°
c = 11.078 (5) ŵ = 0.09 mm1
α = 99.213 (5)°T = 293 K
β = 102.740 (5)°Prism, colourless
γ = 97.767 (5)°0.22 × 0.20 × 0.16 mm
V = 655.6 (7) Å3
Data collection top
Bruker APEXII Kappa CCD-detector
diffractometer
3169 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.036
Graphite monochromatorθmax = 33.3°, θmin = 1.9°
Detector resolution: 0 pixels mm-1h = 109
ω and ϕ scansk = 1414
18424 measured reflectionsl = 1716
4996 independent reflections
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)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.173H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0847P)2 + 0.1309P]
where P = (Fo2 + 2Fc2)/3
4996 reflections(Δ/σ)max = 0.014
183 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C15H14N4Oγ = 97.767 (5)°
Mr = 266.3V = 655.6 (7) Å3
Triclinic, P1Z = 2
a = 6.682 (5) ÅMo Kα radiation
b = 9.347 (5) ŵ = 0.09 mm1
c = 11.078 (5) ÅT = 293 K
α = 99.213 (5)°0.22 × 0.20 × 0.16 mm
β = 102.740 (5)°
Data collection top
Bruker APEXII Kappa CCD-detector
diffractometer
3169 reflections with I > 2σ(I)
18424 measured reflectionsRint = 0.036
4996 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0570 restraints
wR(F2) = 0.173H-atom parameters constrained
S = 0.99Δρmax = 0.30 e Å3
4996 reflectionsΔρmin = 0.29 e Å3
183 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
O10.22065 (13)0.57205 (11)0.58851 (9)0.0380 (2)
C20.52515 (18)0.74174 (14)0.57658 (11)0.0306 (3)
N10.23543 (18)0.67259 (14)0.41251 (11)0.0406 (3)
C60.64969 (18)0.74989 (14)0.70869 (12)0.0304 (2)
C50.52503 (19)0.63581 (14)0.76101 (12)0.0315 (3)
C70.6205 (2)0.60943 (15)0.88018 (13)0.0377 (3)
C40.32984 (19)0.55767 (14)0.70373 (12)0.0315 (3)
C30.32497 (19)0.66098 (15)0.52808 (12)0.0320 (3)
C80.6664 (2)0.90474 (14)0.78630 (12)0.0332 (3)
N30.21879 (18)0.45814 (14)0.74817 (12)0.0439 (3)
H3A0.09680.41420.70440.053*
H3B0.26920.43790.82060.053*
N20.38757 (19)0.76374 (15)0.38430 (11)0.0432 (3)
H20.37360.79120.31290.052*
N40.7004 (2)0.59058 (17)0.97741 (14)0.0571 (4)
C10.5621 (2)0.80702 (16)0.47848 (13)0.0376 (3)
C140.8640 (2)0.70915 (18)0.70847 (16)0.0438 (3)
H14A0.84670.61160.65990.066*
H14B0.93970.71240.79360.066*
H14C0.94010.77790.67180.066*
C130.4882 (2)0.95084 (17)0.81184 (15)0.0442 (3)
H130.36170.88590.78410.053*
C90.8513 (3)1.00406 (18)0.82993 (17)0.0517 (4)
H90.97380.97680.81500.062*
C100.8558 (3)1.1452 (2)0.89631 (18)0.0639 (5)
H100.98171.21090.92510.077*
C150.7477 (3)0.9053 (2)0.46603 (16)0.0536 (4)
H15A0.84480.84690.44110.080*
H15B0.81300.97010.54560.080*
H15C0.70510.96250.40330.080*
C120.4943 (3)1.0905 (2)0.87732 (17)0.0568 (4)
H120.37271.11860.89300.068*
C110.6797 (4)1.18818 (19)0.91953 (16)0.0595 (5)
H110.68431.28260.96350.071*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0256 (4)0.0500 (6)0.0318 (5)0.0082 (4)0.0019 (3)0.0142 (4)
C20.0260 (5)0.0314 (6)0.0302 (6)0.0015 (4)0.0032 (4)0.0049 (4)
N10.0346 (6)0.0480 (7)0.0319 (6)0.0072 (5)0.0007 (4)0.0116 (5)
C60.0233 (5)0.0309 (6)0.0322 (6)0.0011 (4)0.0012 (4)0.0056 (4)
C50.0272 (5)0.0296 (6)0.0320 (6)0.0019 (4)0.0014 (4)0.0073 (5)
C70.0308 (6)0.0350 (7)0.0397 (7)0.0061 (5)0.0026 (5)0.0109 (5)
C40.0266 (5)0.0338 (6)0.0303 (6)0.0004 (4)0.0013 (4)0.0072 (5)
C30.0273 (5)0.0362 (6)0.0290 (6)0.0015 (4)0.0029 (4)0.0073 (5)
C80.0330 (6)0.0318 (6)0.0286 (6)0.0033 (5)0.0005 (5)0.0066 (5)
N30.0331 (6)0.0509 (7)0.0396 (6)0.0111 (5)0.0038 (5)0.0191 (5)
N20.0415 (6)0.0517 (7)0.0308 (6)0.0082 (5)0.0030 (5)0.0144 (5)
N40.0472 (7)0.0635 (9)0.0477 (8)0.0143 (6)0.0114 (6)0.0260 (7)
C10.0327 (6)0.0407 (7)0.0352 (7)0.0031 (5)0.0057 (5)0.0075 (5)
C140.0271 (6)0.0477 (8)0.0529 (9)0.0045 (5)0.0052 (6)0.0076 (7)
C130.0464 (8)0.0385 (8)0.0450 (8)0.0025 (6)0.0122 (6)0.0034 (6)
C90.0384 (7)0.0422 (8)0.0600 (10)0.0085 (6)0.0025 (7)0.0016 (7)
C100.0682 (12)0.0430 (9)0.0577 (11)0.0165 (8)0.0087 (9)0.0007 (8)
C150.0450 (8)0.0609 (10)0.0498 (9)0.0142 (7)0.0090 (7)0.0193 (8)
C120.0746 (12)0.0457 (9)0.0514 (10)0.0136 (8)0.0213 (9)0.0032 (7)
C110.0922 (14)0.0371 (8)0.0405 (8)0.0039 (9)0.0083 (9)0.0001 (6)
Geometric parameters (Å, º) top
O1—C41.3602 (16)N2—C11.3465 (19)
O1—C31.3611 (16)N2—H20.8600
C2—C11.3799 (19)C1—C151.486 (2)
C2—C31.3885 (18)C14—H14A0.9600
C2—C61.5001 (18)C14—H14B0.9600
N1—C31.3164 (17)C14—H14C0.9600
N1—N21.3595 (17)C13—C121.379 (2)
C6—C51.5289 (18)C13—H130.9300
C6—C141.531 (2)C9—C101.397 (3)
C6—C81.5369 (19)C9—H90.9300
C5—C41.3661 (18)C10—C111.357 (3)
C5—C71.4091 (19)C10—H100.9300
C7—N41.1440 (19)C15—H15A0.9600
C4—N31.3340 (17)C15—H15B0.9600
C8—C91.380 (2)C15—H15C0.9600
C8—C131.390 (2)C12—C111.374 (3)
N3—H3A0.8600C12—H120.9300
N3—H3B0.8600C11—H110.9300
C4—O1—C3115.59 (10)N2—C1—C2106.17 (12)
C1—C2—C3103.33 (11)N2—C1—C15122.22 (14)
C1—C2—C6133.30 (11)C2—C1—C15131.61 (13)
C3—C2—C6123.33 (11)C6—C14—H14A109.5
C3—N1—N2101.74 (11)C6—C14—H14B109.5
C2—C6—C5105.36 (10)H14A—C14—H14B109.5
C2—C6—C14110.78 (11)C6—C14—H14C109.5
C5—C6—C14109.28 (12)H14A—C14—H14C109.5
C2—C6—C8109.09 (10)H14B—C14—H14C109.5
C5—C6—C8109.98 (11)C12—C13—C8121.64 (15)
C14—C6—C8112.12 (10)C12—C13—H13119.2
C4—C5—C7116.92 (12)C8—C13—H13119.2
C4—C5—C6126.31 (11)C8—C9—C10120.50 (17)
C7—C5—C6116.77 (11)C8—C9—H9119.8
N4—C7—C5178.69 (15)C10—C9—H9119.8
N3—C4—O1110.00 (11)C11—C10—C9121.11 (17)
N3—C4—C5127.07 (12)C11—C10—H10119.4
O1—C4—C5122.93 (12)C9—C10—H10119.4
N1—C3—O1119.33 (11)C1—C15—H15A109.5
N1—C3—C2114.94 (12)C1—C15—H15B109.5
O1—C3—C2125.71 (12)H15A—C15—H15B109.5
C9—C8—C13117.40 (14)C1—C15—H15C109.5
C9—C8—C6123.01 (13)H15A—C15—H15C109.5
C13—C8—C6119.57 (11)H15B—C15—H15C109.5
C4—N3—H3A120.0C11—C12—C13120.16 (18)
C4—N3—H3B120.0C11—C12—H12119.9
H3A—N3—H3B120.0C13—C12—H12119.9
C1—N2—N1113.80 (12)C10—C11—C12119.19 (17)
C1—N2—H2123.1C10—C11—H11120.4
N1—N2—H2123.1C12—C11—H11120.4
C1—C2—C6—C5173.79 (14)C6—C2—C3—N1176.69 (12)
C3—C2—C6—C58.91 (17)C1—C2—C3—O1177.46 (13)
C1—C2—C6—C1455.7 (2)C6—C2—C3—O14.6 (2)
C3—C2—C6—C14126.98 (14)C2—C6—C8—C9111.80 (15)
C1—C2—C6—C868.17 (18)C5—C6—C8—C9133.10 (14)
C3—C2—C6—C8109.13 (14)C14—C6—C8—C911.29 (19)
C2—C6—C5—C47.33 (18)C2—C6—C8—C1366.30 (15)
C14—C6—C5—C4126.40 (15)C5—C6—C8—C1348.80 (16)
C8—C6—C5—C4110.12 (15)C14—C6—C8—C13170.61 (13)
C2—C6—C5—C7173.06 (12)C3—N1—N2—C10.42 (17)
C14—C6—C5—C753.99 (16)N1—N2—C1—C20.34 (18)
C8—C6—C5—C769.50 (15)N1—N2—C1—C15179.23 (15)
C4—C5—C7—N4158 (8)C3—C2—C1—N20.91 (15)
C6—C5—C7—N421 (8)C6—C2—C1—N2176.77 (14)
C3—O1—C4—N3174.36 (12)C3—C2—C1—C15178.61 (17)
C3—O1—C4—C55.24 (19)C6—C2—C1—C153.7 (3)
C7—C5—C4—N30.2 (2)C9—C8—C13—C120.5 (2)
C6—C5—C4—N3179.80 (13)C6—C8—C13—C12177.74 (14)
C7—C5—C4—O1179.72 (12)C13—C8—C9—C100.4 (2)
C6—C5—C4—O10.7 (2)C6—C8—C9—C10177.75 (15)
N2—N1—C3—O1177.77 (12)C8—C9—C10—C110.0 (3)
N2—N1—C3—C21.06 (17)C8—C13—C12—C110.2 (3)
C4—O1—C3—N1175.29 (12)C9—C10—C11—C120.3 (3)
C4—O1—C3—C23.4 (2)C13—C12—C11—C100.2 (3)
C1—C2—C3—N11.29 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N1i0.862.273.129 (2)173
N3—H3B···N4ii0.862.263.087 (2)160
C10—H10···N4iii0.932.533.455 (3)172
C14—H14A···N1iv0.962.593.522 (3)163
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y+1, z+2; (iii) x+2, y+2, z+2; (iv) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC15H14N4O
Mr266.3
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)6.682 (5), 9.347 (5), 11.078 (5)
α, β, γ (°)99.213 (5), 102.740 (5), 97.767 (5)
V3)655.6 (7)
Z2
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.22 × 0.20 × 0.16
Data collection
DiffractometerBruker APEXII Kappa CCD-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
18424, 4996, 3169
Rint0.036
(sin θ/λ)max1)0.771
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.173, 0.99
No. of reflections4996
No. of parameters183
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.30, 0.29

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3A···N1i0.862.273.129 (2)172.6
N3—H3B···N4ii0.862.263.087 (2)160.2
C10—H10···N4iii0.932.533.455 (3)172.2
C14—H14A···N1iv0.962.593.522 (3)162.6
Symmetry codes: (i) x, y+1, z+1; (ii) x+1, y+1, z+2; (iii) x+2, y+2, z+2; (iv) x+1, y+1, z+1.
 

Acknowledgements

The authors acknowledge the Centre of Excellence in Bioinformatics, Pondicherry University, for providing the facilities for carrying out this work. RK and MK thank the University Grant Commission for providing a Major Research Project and Rajiv Gandhi National Fellowship, respectively. GV thanks the Department of Science and Technology, New Delhi, Government of India (grant No. SR/S5/GC-22/2007) for financial support.

References

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