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Acta Crystallogr Sect E Struct Rep Online. 2008 January 1; 64(Pt 1): o341.
Published online 2007 December 21. doi:  10.1107/S1600536807064926
PMCID: PMC2915382

6′-Amino-3′-methyl-2-oxo-1′-phenyl-1′,3a′,4′,7a′-tetra­hydrospiro­[1H-indole-3(2H),4′-pyrano[2,3-d]pyrazole]-5′-carbonitrile

Abstract

In the crystal structure of the title compound, C21H15N5O2, the planar indolone unit and the pyran ring are almost perpendicular to each other [dihedral angle = 89.41 (2)°], and the pyrazole and phenyl rings are oriented at an angle of 25.74 (1)°. The mol­ecular packing is stabilized by inter- and intra­molecular C—H(...)O, N—H(...)O and C—H(...)π hydrogen bonds.

Related literature

For related literature, see: Houlihan et al. (1992 [triangle]); Jeyabharathi et al. (2001 [triangle]); Kang et al. (2002 [triangle]); Khafagy et al. (2002 [triangle]); McSweeney et al. (2004 [triangle]), Selvanayagam et al. (2005 [triangle]); Usui et al. (1998 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-0o341-scheme1.jpg

Experimental

Crystal data

  • C21H15N5O2
  • M r = 369.38
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o341-efi1.jpg
  • a = 10.0370 (3) Å
  • b = 21.9705 (6) Å
  • c = 8.2325 (2) Å
  • β = 98.761 (1)°
  • V = 1794.23 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 293 (2) K
  • 0.24 × 0.21 × 0.20 mm

Data collection

  • Bruker Kappa APEXII diffractometer
  • Absorption correction: multi-scan (SAINT; Bruker, 1999 [triangle]) T min = 0.978, T max = 0.982
  • 21620 measured reflections
  • 4485 independent reflections
  • 3277 reflections with I > 2σ(I)
  • R int = 0.028

Refinement

  • R[F 2 > 2σ(F 2)] = 0.041
  • wR(F 2) = 0.118
  • S = 1.02
  • 4485 reflections
  • 254 parameters
  • H-atom parameters constrained
  • Δρmax = 0.24 e Å−3
  • Δρmin = −0.17 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT (Bruker, 1999 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 [triangle]); molecular graphics: PLATON (Spek, 2003 [triangle]); software used to prepare material for publication: SHELXL97 and PARST97 (Nardelli, 1995 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536807064926/lw2047sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536807064926/lw2047Isup2.hkl

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

Acknowledgments

SE thanks the Council of Scientific and Industrial Research (CSIR), New Delhi, for providing financial assistance as a Senior Research Fellowship (SRF).

supplementary crystallographic information

Comment

The indole moiety is probably the most well known heterocycle, a common and important feature of a variety of natural products and medicinal agents (Houlihan et al., 1992). Spiro compounds represent an important class of naturally occurring substances characterized by highly pronounced biological properties. The spiro indolone system is the core structure of many pharmacological agents and natural alkaloids (Usui et al., 1998). For example, spirotryprostatin A, a natural alkaloid isolated from the fermentation broth of Aspergillus fumigatus, has been identified as a novel inhibitor of microtubule assembly (Khafagy et al., 2002), and pteropodine and isopteropodine have been shown to modulate the function of muscarinic serotonin receptors (Kang et al., 2002). In view of the above properties of spiro indolone derivatives, the crystal structure analysis of the title compound was undertaken. The indolone and the pyrano pyrazole moities are connected through a spiro junction in the molecule. The dihedral angle between the planar indolone ring and pyrano ring(mean plane calculated through atoms C9,C10,O2,C11, C13) is 89.41 (2)°, which indicates that the rings are perpendicularto each other, also the dihedral angle between the pyrazole ring and the phenyl ring is 25.74 (1)° and the pyrano ring is 3.98 (1)°. The gemoetry of the indolone and pyrano pyrazole moieties are comparable with literature values(Jeyabharathi et al., 2001, Selvanayagam et al.,2005, McSweeney et al., 2004), a slight distortion of bond lengths and angles is seen around the C1 atom due to spiro charecter and in the pyrano ring the angle between (C11—O2—C10) 113.87 (1)° which is lower compared to the literature value (McSweeney et al., 2004). The bond length of C9—C14 (sp2-sp) 1.42 (2)° is long due to sp2 hybridization. The cyanide group orients with pyrano ring (O2—C10—C19—C14) -178.4 (1)° in -anti-periplanar(-ap) conformation, while the amino group orients (C11—O2—C10—N3) 176.1 (1)° in +ap conformation. The angle of (C13—C12—C21) 127.83 (1) and (C1—C13—C12) 133.86 (1) is above the normal value due to the steric hindarance of the bulky indolone ring and the methyl group.

The packing of the molecules viewed along C axis is shown in Figure 2 and the hydrogen bond geometry are given in Table 2. The molecular packing is stabilzed by inter and intra molecular C—H..O, N—H···O and C—H···pi hydrogen bonds.

Experimental

1-methyl isatin (0.161 g, 1 mmol), malononitrile (0.066 g, 1 mmol) and 1-phenyl-3-methyl pyrazolon-5-one (0.174 g, 1 mmol) were added to silica gel impregnated with indium(III) chloride (44 mg, 20 mol°), prepared by adding a solution of InCl3 in a minimum amount of THF to silica gel (2 g, 100–200 mesh activated by heating for 4 h at 150° before use), followed by complete evaporation of solvent under vacuum. The whole mixture was stirred for 5 min for uniform mixing and then irradiated in a microwave oven at 300 W for 3 min. On completion, the reaction mixture was directly charged on a small silica gel column and eluted with a mixture of ethyl acetate-hexane (4:6) to afford the pure product in 88° yield as a white solid. Crystals of (I) were grown by slow evaporation from ethanol.

Figures

Fig. 1.
: The ORTEP diagram of the title compound with 30% probability displacement ellipsoids.
Fig. 2.
: Packing of the molecules viewed down c axis, the dashed lines represent hydrogen bonds.

Crystal data

C21H15N5O2F000 = 768
Mr = 369.38Dx = 1.367 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P2ybcCell parameters from 4485 reflections
a = 10.0370 (3) Åθ = 2.7–28.4º
b = 21.9705 (6) ŵ = 0.09 mm1
c = 8.2325 (2) ÅT = 293 (2) K
β = 98.761 (1)ºCubic, colourless
V = 1794.23 (8) Å30.24 × 0.21 × 0.20 mm
Z = 4

Data collection

Bruker Kappa APEXII diffractometer4485 independent reflections
Radiation source: fine-focus sealed tube3277 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.028
T = 293(2) Kθmax = 28.4º
ω and [var phi] scansθmin = 2.7º
Absorption correction: multi-scan(SAINT; Bruker, 1999)h = −13→13
Tmin = 0.978, Tmax = 0.982k = −29→29
21620 measured reflectionsl = −10→10

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.041Calculated w = 1/[σ2(Fo2) + (0.0549P)2 + 0.3722P] where P = (Fo2 + 2Fc2)/3 ?
wR(F2) = 0.118(Δ/σ)max < 0.001
S = 1.02Δρmax = 0.24 e Å3
4485 reflectionsΔρmin = −0.17 e Å3
254 parametersExtinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0028 (11)
Secondary atom site location: difference Fourier map

Special details

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
N10.94447 (12)0.45685 (6)0.30510 (15)0.0484 (3)
H11.02210.47180.34360.058*
N20.63637 (18)0.56417 (7)0.0884 (2)0.0705 (4)
N30.37828 (13)0.49908 (6)0.28737 (17)0.0560 (4)
H3A0.38200.53180.23090.067*
H3B0.30710.49100.32980.067*
N40.53791 (11)0.31470 (5)0.49407 (14)0.0416 (3)
N50.65120 (12)0.27975 (6)0.49024 (16)0.0467 (3)
O10.83478 (10)0.47928 (5)0.52173 (12)0.0524 (3)
O20.45453 (9)0.41161 (4)0.40050 (12)0.0434 (2)
C10.71934 (12)0.42403 (6)0.27907 (15)0.0354 (3)
C20.83874 (13)0.45672 (6)0.38640 (16)0.0400 (3)
C30.91361 (14)0.42960 (6)0.14910 (17)0.0423 (3)
C40.99616 (17)0.42282 (8)0.0305 (2)0.0555 (4)
H41.08520.43600.04770.067*
C50.9396 (2)0.39532 (8)−0.1154 (2)0.0611 (5)
H50.99150.3907−0.19910.073*
C60.80860 (19)0.37474 (7)−0.13958 (19)0.0567 (4)
H60.77380.3561−0.23840.068*
C70.72765 (16)0.38144 (6)−0.01793 (17)0.0459 (3)
H70.63930.3673−0.03390.055*
C80.78159 (14)0.40946 (6)0.12661 (16)0.0375 (3)
C90.60089 (13)0.46759 (6)0.24995 (16)0.0374 (3)
C100.48299 (14)0.46081 (6)0.30913 (16)0.0392 (3)
C110.55303 (12)0.36842 (6)0.41973 (16)0.0366 (3)
C120.73234 (14)0.31320 (6)0.41359 (17)0.0418 (3)
C130.67407 (12)0.37005 (6)0.36648 (15)0.0359 (3)
C140.61894 (15)0.52139 (7)0.16089 (18)0.0445 (3)
C150.42476 (13)0.28945 (7)0.55574 (16)0.0414 (3)
C160.33155 (19)0.32592 (8)0.6121 (2)0.0658 (5)
H160.34170.36800.61310.079*
C170.2218 (2)0.29945 (10)0.6676 (3)0.0811 (6)
H170.15790.32410.70580.097*
C180.20561 (18)0.23795 (9)0.6674 (2)0.0682 (5)
H180.13100.22070.70420.082*
C190.29922 (18)0.20212 (9)0.6129 (2)0.0669 (5)
H190.28930.16000.61380.080*
C200.40913 (17)0.22731 (7)0.5562 (2)0.0580 (4)
H200.47260.20230.51830.070*
C210.86622 (16)0.28962 (8)0.3862 (2)0.0615 (5)
H21A0.87910.24940.43140.092*
H21B0.93590.31600.43910.092*
H21C0.86990.28830.27040.092*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.0335 (6)0.0648 (8)0.0489 (7)−0.0131 (6)0.0126 (5)−0.0126 (6)
N20.0949 (12)0.0515 (8)0.0673 (9)−0.0072 (8)0.0194 (8)0.0063 (7)
N30.0533 (8)0.0583 (8)0.0608 (8)0.0199 (6)0.0225 (6)0.0096 (6)
N40.0356 (6)0.0435 (6)0.0475 (6)−0.0009 (5)0.0122 (5)0.0011 (5)
N50.0378 (6)0.0464 (7)0.0569 (7)0.0024 (5)0.0108 (5)0.0051 (6)
O10.0406 (5)0.0763 (7)0.0418 (5)−0.0155 (5)0.0111 (4)−0.0182 (5)
O20.0358 (5)0.0462 (5)0.0508 (6)0.0044 (4)0.0146 (4)0.0022 (4)
C10.0312 (6)0.0404 (7)0.0349 (6)−0.0042 (5)0.0063 (5)−0.0047 (5)
C20.0334 (7)0.0466 (7)0.0407 (7)−0.0057 (6)0.0082 (5)−0.0040 (6)
C30.0418 (7)0.0423 (7)0.0455 (7)0.0001 (6)0.0150 (6)−0.0029 (6)
C40.0509 (9)0.0594 (9)0.0623 (10)0.0043 (7)0.0280 (8)−0.0017 (8)
C50.0773 (12)0.0601 (10)0.0535 (9)0.0170 (9)0.0338 (9)−0.0017 (8)
C60.0802 (12)0.0495 (9)0.0418 (8)0.0128 (8)0.0140 (8)−0.0073 (6)
C70.0544 (9)0.0417 (7)0.0412 (7)0.0015 (6)0.0064 (6)−0.0050 (6)
C80.0409 (7)0.0358 (6)0.0374 (7)0.0009 (5)0.0109 (5)−0.0007 (5)
C90.0381 (7)0.0375 (7)0.0367 (6)−0.0006 (5)0.0057 (5)−0.0046 (5)
C100.0398 (7)0.0416 (7)0.0363 (7)0.0029 (6)0.0060 (5)−0.0044 (5)
C110.0320 (6)0.0400 (7)0.0382 (7)−0.0002 (5)0.0066 (5)−0.0029 (5)
C120.0342 (7)0.0445 (7)0.0469 (8)0.0000 (6)0.0063 (6)0.0001 (6)
C130.0299 (6)0.0413 (7)0.0364 (6)−0.0033 (5)0.0047 (5)−0.0028 (5)
C140.0482 (8)0.0430 (8)0.0429 (7)−0.0006 (6)0.0086 (6)−0.0049 (6)
C150.0366 (7)0.0502 (8)0.0388 (7)−0.0049 (6)0.0099 (5)−0.0001 (6)
C160.0685 (11)0.0557 (10)0.0830 (13)−0.0057 (8)0.0431 (10)−0.0117 (9)
C170.0702 (12)0.0807 (14)0.1060 (16)0.0021 (10)0.0569 (12)−0.0063 (12)
C180.0531 (10)0.0820 (13)0.0748 (12)−0.0128 (9)0.0268 (9)0.0111 (10)
C190.0603 (11)0.0599 (10)0.0837 (13)−0.0114 (9)0.0218 (9)0.0131 (9)
C200.0517 (9)0.0494 (9)0.0772 (11)0.0013 (7)0.0237 (8)0.0091 (8)
C210.0414 (8)0.0590 (10)0.0872 (13)0.0085 (7)0.0196 (8)0.0120 (9)

Geometric parameters (Å, °)

N1—C21.3381 (17)C6—C71.390 (2)
N1—C31.4081 (18)C6—H60.9300
N1—H10.8600C7—C81.3754 (19)
N2—C141.141 (2)C7—H70.9300
N3—C101.3366 (18)C9—C101.3548 (18)
N3—H3A0.8600C9—C141.417 (2)
N3—H3B0.8600C11—C131.3534 (17)
N4—C111.3488 (17)C12—C131.4084 (19)
N4—N51.3764 (16)C12—C211.489 (2)
N4—C151.4251 (16)C15—C161.366 (2)
N5—C121.3258 (17)C15—C201.374 (2)
O1—C21.2255 (16)C16—C171.384 (2)
O2—C111.3620 (15)C16—H160.9300
O2—C101.3716 (16)C17—C181.361 (3)
C1—C131.4935 (18)C17—H170.9300
C1—C91.5166 (18)C18—C191.353 (3)
C1—C81.5189 (17)C18—H180.9300
C1—C21.5525 (18)C19—C201.378 (2)
C3—C41.3813 (19)C19—H190.9300
C3—C81.3824 (19)C20—H200.9300
C4—C51.387 (2)C21—H21A0.9600
C4—H40.9300C21—H21B0.9600
C5—C61.376 (3)C21—H21C0.9600
C5—H50.9300
C2—N1—C3111.98 (11)C10—C9—C1125.48 (12)
C2—N1—H1124.0C14—C9—C1116.69 (11)
C3—N1—H1124.0N3—C10—C9126.49 (13)
C10—N3—H3A120.0N3—C10—O2110.13 (12)
C10—N3—H3B120.0C9—C10—O2123.38 (12)
H3A—N3—H3B120.0N4—C11—C13109.79 (11)
C11—N4—N5109.11 (10)N4—C11—O2122.18 (11)
C11—N4—C15130.78 (11)C13—C11—O2127.99 (12)
N5—N4—C15119.80 (11)N5—C12—C13111.30 (12)
C12—N5—N4105.73 (11)N5—C12—C21120.88 (13)
C11—O2—C10113.87 (10)C13—C12—C21127.82 (13)
C13—C1—C9106.77 (10)C11—C13—C12104.06 (11)
C13—C1—C8115.12 (11)C11—C13—C1122.07 (12)
C9—C1—C8114.43 (11)C12—C13—C1133.86 (11)
C13—C1—C2111.00 (11)N2—C14—C9178.35 (17)
C9—C1—C2108.46 (10)C16—C15—C20119.84 (14)
C8—C1—C2100.88 (10)C16—C15—N4121.12 (14)
O1—C2—N1126.29 (13)C20—C15—N4119.03 (13)
O1—C2—C1125.13 (11)C15—C16—C17119.13 (17)
N1—C2—C1108.58 (11)C15—C16—H16120.4
C4—C3—C8122.46 (14)C17—C16—H16120.4
C4—C3—N1128.18 (14)C18—C17—C16121.16 (17)
C8—C3—N1109.36 (11)C18—C17—H17119.4
C3—C4—C5116.65 (16)C16—C17—H17119.4
C3—C4—H4121.7C19—C18—C17119.31 (16)
C5—C4—H4121.7C19—C18—H18120.3
C6—C5—C4121.65 (14)C17—C18—H18120.3
C6—C5—H5119.2C18—C19—C20120.70 (17)
C4—C5—H5119.2C18—C19—H19119.6
C5—C6—C7120.77 (15)C20—C19—H19119.6
C5—C6—H6119.6C15—C20—C19119.85 (16)
C7—C6—H6119.6C15—C20—H20120.1
C8—C7—C6118.32 (15)C19—C20—H20120.1
C8—C7—H7120.8C12—C21—H21A109.5
C6—C7—H7120.8C12—C21—H21B109.5
C7—C8—C3120.14 (12)H21A—C21—H21B109.5
C7—C8—C1130.69 (12)C12—C21—H21C109.5
C3—C8—C1109.17 (11)H21A—C21—H21C109.5
C10—C9—C14117.73 (12)H21B—C21—H21C109.5
C11—N4—N5—C120.01 (15)C11—O2—C10—N3176.12 (11)
C15—N4—N5—C12174.29 (12)C11—O2—C10—C9−3.13 (18)
C3—N1—C2—O1−177.13 (15)N5—N4—C11—C13−0.03 (15)
C3—N1—C2—C11.82 (17)C15—N4—C11—C13−173.48 (13)
C13—C1—C2—O1−60.38 (18)N5—N4—C11—O2177.86 (11)
C9—C1—C2—O156.62 (18)C15—N4—C11—O24.4 (2)
C8—C1—C2—O1177.16 (14)C10—O2—C11—N4−174.36 (12)
C13—C1—C2—N1120.66 (12)C10—O2—C11—C133.11 (19)
C9—C1—C2—N1−122.35 (12)N4—N5—C12—C130.02 (16)
C8—C1—C2—N1−1.81 (15)N4—N5—C12—C21−179.85 (14)
C2—N1—C3—C4178.50 (15)N4—C11—C13—C120.04 (15)
C2—N1—C3—C8−1.03 (18)O2—C11—C13—C12−177.69 (13)
C8—C3—C4—C50.9 (2)N4—C11—C13—C1180.00 (11)
N1—C3—C4—C5−178.53 (15)O2—C11—C13—C12.3 (2)
C3—C4—C5—C6−1.3 (3)N5—C12—C13—C11−0.03 (16)
C4—C5—C6—C70.6 (3)C21—C12—C13—C11179.83 (15)
C5—C6—C7—C80.4 (2)N5—C12—C13—C1−179.99 (13)
C6—C7—C8—C3−0.7 (2)C21—C12—C13—C1−0.1 (3)
C6—C7—C8—C1179.10 (14)C9—C1—C13—C11−6.46 (16)
C4—C3—C8—C70.0 (2)C8—C1—C13—C11−134.66 (13)
N1—C3—C8—C7179.58 (13)C2—C1—C13—C11111.56 (14)
C4—C3—C8—C1−179.81 (14)C9—C1—C13—C12173.49 (14)
N1—C3—C8—C1−0.25 (16)C8—C1—C13—C1245.3 (2)
C13—C1—C8—C761.85 (19)C2—C1—C13—C12−68.48 (18)
C9—C1—C8—C7−62.41 (18)C10—C9—C14—N2−176 (100)
C2—C1—C8—C7−178.61 (14)C1—C9—C14—N28(6)
C13—C1—C8—C3−118.34 (13)C11—N4—C15—C16−29.0 (2)
C9—C1—C8—C3117.40 (13)N5—N4—C15—C16158.13 (15)
C2—C1—C8—C31.21 (14)C11—N4—C15—C20150.19 (16)
C13—C1—C9—C106.56 (17)N5—N4—C15—C20−22.7 (2)
C8—C1—C9—C10135.16 (13)C20—C15—C16—C17−0.5 (3)
C2—C1—C9—C10−113.12 (14)N4—C15—C16—C17178.65 (17)
C13—C1—C9—C14−177.13 (11)C15—C16—C17—C180.2 (3)
C8—C1—C9—C14−48.53 (16)C16—C17—C18—C190.5 (4)
C2—C1—C9—C1463.20 (14)C17—C18—C19—C20−0.8 (3)
C14—C9—C10—N32.5 (2)C16—C15—C20—C190.2 (3)
C1—C9—C10—N3178.78 (13)N4—C15—C20—C19−178.97 (15)
C14—C9—C10—O2−178.36 (12)C18—C19—C20—C150.5 (3)
C1—C9—C10—O2−2.1 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C16—H16···O20.932.422.959 (2)117
N1—H1···O1i0.861.992.819 (2)161
N3—H3B···O1ii0.862.122.880 (1)148
C6—H6···Cgiii0.922.853.771 (3)173

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LW2047).

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