3-(2-Methyl­phen­yl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile

Suresh, G.; Srinivasan, J.; Bakthadoss, M.; Aravindhan, S.

doi:10.1107/S1600536812051732

organic compounds

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ISSN: 2056-9890

Volume 69| Part 2| February 2013| Page o181

doi:10.1107/S1600536812051732

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3-(2-Methylphenyl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbonitrile

G. Suresh,^a J. Srinivasan,^b M. Bakthadoss ^b and S. Aravindhan ^a ^*

^aDepartment of Physics, Presidency College (Autonomous), Chennai 600 005, India, and ^bDepartment of Organic Chemistry, University of Madras, Chennai 600 025, India
^*Correspondence e-mail: aravindhanpresidency@gmail.com

(Received 16 December 2012; accepted 22 December 2012; online 4 January 2013)

In the title compound, C₁₈H₁₄N₂O₂, the pyran ring of the chromeno ring system has a half-chair conformation, and the dihedral angle between its mean plane and the benzene ring is 5.3 (2)°. The isoxazole ring forms a dihedral angle of 74.6 (2)° with the attached benzene ring and is inclined to the mean plane of the chromeno ring system by 15.06 (19)°. In the crystal, there are no significant intermolecular interactions.

Related literature

For the biological importance of 4H-chromene derivatives, see: Cai (2007 , 2008 ); Cai et al. (2006 ); Gabor (1988 ); Brooks (1998 ); Valenti et al. (1993 ); Hyana & Saimoto (1987 ); Tang et al. (2007 ). For related structures, see: Gangadharan et al. (2011 ); Swaminathan et al. (2011 ).

Experimental

Crystal data

C₁₈H₁₄N₂O₂
M_r = 290.31
Orthorhombic, P c a 2₁
a = 19.326 (3) Å
b = 10.7866 (17) Å
c = 6.9072 (11) Å
V = 1439.9 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 298 K
0.35 × 0.25 × 0.15 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.970, T_max = 0.987
4742 measured reflections
1750 independent reflections
1100 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.146
S = 1.09
1750 reflections
200 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812051732/su2544sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812051732/su2544Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812051732/su2544Isup3.cml

checkCIF report

Comment top

4H-Chromenes are biologically important compounds used as synthetic ligands for drug designing and discovery process. They exhibit numerous biological and pharmacological properties such as anti-viral, anti-fungal, anti-inflammatory, anti- diabetic, cardionthonic, anti anaphylactic and anti-cancer activity (Cai, 2008; Cai, 2007; Cai et al., 2006; Gabor, 1988; Brooks, 1998; Valenti et al., 1993; Hyana & Saimoto, 1987; Tang et al., 2007). We report herein on the synthesis of a new chromeno compound and its crystal structure.

The molecular structure of the title molecule is illustrated in Fig. 1. In the chromeno ring system, the dihedral angle between the mean plane of the pyran ring, which has a half-chair conformation, and the benzene ring is 5.3 (2)°. The dihedral angle between the mean plane of the chromeno ring system and isoxazole ring is 15.06 (19)°. The isoxazole ring also forms a dihedral angle of 74.6 (2)° with the the benzene ring (C11—C16). The geometric parameters of the title molecule agree well with those reported for closely related structures (Gangadharan et al., 2011; Swaminathan et al., 2011).

In the crystal, there are no significant intermolecular interactions.

Related literature top

For the biological importance of 4H-chromene derivatives, see: Cai (2007, 2008); Cai et al. (2006); Gabor (1988); Brooks (1998); Valenti et al. (1993); Hyana & Saimoto (1987); Tang et al. (2007). For related structures, see: Gangadharan et al. (2011); Swaminathan et al. (2011).

Experimental top

NCS (4 mmol) was added pinch wise over 3h to a solution of (E)-2-((2-((E)-(hydroxyimino)methyl)phenoxy)methyl)-3-o-tolylacrylonitrile(2 mmol) in CCl₄ at 273 - 283 K. After Et₃N (4 mmol) was added to the reaction mixture which was stirred at room temperature for 2 h. After completion of the reaction, the mixture was evaporated under reduced pressure and the resulting crude mass was diluted with water (15 ml) and extracted with ethyl acetate (3 × 15 ml). The combined organic layers washed with brine (2 × 10 ml) and dried over anhydrous Na₂SO₄. The organic layer was evaporated and purified by column chromatography (silica gel 60–120 mesh; 7% EtOAc in hexanes) to provide the desired title product as a colourless solid. Crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the title compound in ethyl acetate at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. The molecular structure of the title compound, with the atom labeling. Displacement ellipsoids are drawn at the 30% probability level.

3-(2-Methylphenyl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a- carbonitrile top

Crystal data top

C₁₈H₁₄N₂O₂	F(000) = 608
M_r = 290.31	D_x = 1.339 Mg m⁻³
Orthorhombic, Pca2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2ac	Cell parameters from 1750 reflections
a = 19.326 (3) Å	θ = 1.9–27.7°
b = 10.7866 (17) Å	µ = 0.09 mm⁻¹
c = 6.9072 (11) Å	T = 298 K
V = 1439.9 (4) Å³	Orthorhombic, colourless
Z = 4	0.35 × 0.25 × 0.15 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	1750 independent reflections
Radiation source: fine-focus sealed tube	1100 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
ω and ϕ scans	θ_max = 27.7°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −24→25
T_min = 0.970, T_max = 0.987	k = −10→13
4742 measured reflections	l = −8→6

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.146	H-atom parameters constrained
S = 1.09	w = 1/[σ²(F_o²) + (0.0456P)² + 0.5663P] where P = (F_o² + 2F_c²)/3
1750 reflections	(Δ/σ)_max < 0.001
200 parameters	Δρ_max = 0.21 e Å⁻³
1 restraint	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₈H₁₄N₂O₂	V = 1439.9 (4) Å³
M_r = 290.31	Z = 4
Orthorhombic, Pca2₁	Mo Kα radiation
a = 19.326 (3) Å	µ = 0.09 mm⁻¹
b = 10.7866 (17) Å	T = 298 K
c = 6.9072 (11) Å	0.35 × 0.25 × 0.15 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	1750 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	1100 reflections with I > 2σ(I)
T_min = 0.970, T_max = 0.987	R_int = 0.047
4742 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.059	1 restraint
wR(F²) = 0.146	H-atom parameters constrained
S = 1.09	Δρ_max = 0.21 e Å⁻³
1750 reflections	Δρ_min = −0.17 e Å⁻³
200 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

	x	y	z	U_iso*/U_eq
C1	0.8559 (2)	−0.2941 (4)	0.6812 (9)	0.0493 (12)
C2	0.8529 (2)	−0.4218 (5)	0.6834 (12)	0.0659 (16)
H2	0.8639	−0.4667	0.5727	0.079*
C3	0.8336 (3)	−0.4824 (5)	0.8491 (13)	0.0725 (18)
H3	0.8311	−0.5685	0.8502	0.087*
C4	0.8177 (2)	−0.4155 (6)	1.0168 (11)	0.0717 (18)
H4	0.8053	−0.4572	1.1294	0.086*
C5	0.8204 (2)	−0.2907 (5)	1.0155 (9)	0.0597 (14)
H5	0.8093	−0.2470	1.1274	0.072*
C6	0.8397 (2)	−0.2254 (5)	0.8478 (8)	0.0494 (13)
C7	0.84595 (19)	−0.0931 (5)	0.8391 (7)	0.0421 (12)
C8	0.8522 (2)	0.0964 (4)	0.6809 (8)	0.0457 (11)
H8	0.8093	0.1013	0.6058	0.055*
C9	0.88122 (19)	−0.0358 (4)	0.6634 (7)	0.0384 (10)
C10	0.8602 (2)	−0.1104 (5)	0.4876 (8)	0.0482 (12)
H10A	0.8109	−0.1007	0.4659	0.058*
H10B	0.8842	−0.0789	0.3746	0.058*
C11	0.8981 (2)	0.2017 (4)	0.6220 (7)	0.0434 (12)
C12	0.9523 (2)	0.2369 (4)	0.7453 (9)	0.0558 (14)
H12	0.9572	0.1988	0.8653	0.067*
C13	0.9984 (2)	0.3274 (5)	0.6900 (11)	0.0674 (17)
H13	1.0337	0.3520	0.7733	0.081*
C14	0.9919 (3)	0.3817 (5)	0.5095 (13)	0.0744 (19)
H14	1.0239	0.4406	0.4686	0.089*
C15	0.9383 (3)	0.3483 (5)	0.3917 (9)	0.0618 (14)
H15	0.9341	0.3865	0.2716	0.074*
C16	0.8901 (2)	0.2600 (4)	0.4442 (8)	0.0474 (12)
C17	0.8323 (3)	0.2283 (5)	0.3092 (9)	0.0668 (15)
H17A	0.7888	0.2425	0.3726	0.100*
H17B	0.8357	0.1426	0.2726	0.100*
H17C	0.8353	0.2793	0.1957	0.100*
C18	0.9575 (2)	−0.0430 (4)	0.6899 (7)	0.0412 (10)
N1	0.82063 (19)	−0.0141 (4)	0.9557 (7)	0.0556 (11)
N2	1.01564 (18)	−0.0484 (4)	0.7066 (7)	0.0570 (11)
O1	0.87563 (16)	−0.2367 (3)	0.5112 (6)	0.0556 (9)
O2	0.83494 (17)	0.1062 (3)	0.8863 (5)	0.0582 (9)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.038 (2)	0.057 (3)	0.054 (3)	−0.001 (2)	0.006 (2)	−0.002 (3)
C2	0.054 (3)	0.056 (4)	0.088 (5)	0.003 (2)	0.001 (3)	−0.021 (4)
C3	0.059 (3)	0.048 (3)	0.110 (6)	−0.003 (2)	−0.006 (3)	0.005 (4)
C4	0.051 (3)	0.083 (4)	0.081 (5)	0.001 (3)	0.006 (3)	0.025 (5)
C5	0.050 (3)	0.075 (4)	0.055 (4)	0.008 (3)	0.008 (3)	0.005 (3)
C6	0.034 (2)	0.069 (3)	0.046 (3)	0.002 (2)	0.003 (2)	−0.002 (3)
C7	0.035 (2)	0.058 (3)	0.033 (3)	0.004 (2)	0.0013 (19)	−0.009 (3)
C8	0.043 (2)	0.056 (3)	0.038 (3)	0.003 (2)	−0.004 (2)	−0.005 (3)
C9	0.042 (2)	0.045 (2)	0.029 (2)	0.0030 (18)	0.0034 (19)	−0.007 (2)
C10	0.047 (2)	0.062 (3)	0.036 (3)	0.001 (2)	0.004 (2)	−0.009 (3)
C11	0.041 (2)	0.042 (3)	0.047 (3)	0.0072 (19)	0.001 (2)	−0.015 (2)
C12	0.054 (3)	0.055 (3)	0.057 (4)	0.010 (2)	−0.014 (2)	−0.004 (3)
C13	0.050 (3)	0.056 (3)	0.097 (5)	−0.001 (2)	−0.019 (3)	−0.012 (4)
C14	0.055 (3)	0.062 (4)	0.106 (6)	−0.001 (2)	0.003 (3)	−0.001 (4)
C15	0.065 (3)	0.064 (3)	0.057 (4)	0.008 (3)	0.005 (3)	−0.003 (3)
C16	0.051 (2)	0.044 (3)	0.047 (3)	0.009 (2)	0.001 (2)	−0.010 (3)
C17	0.087 (4)	0.068 (4)	0.045 (4)	−0.005 (3)	−0.015 (3)	0.005 (3)
C18	0.044 (2)	0.049 (3)	0.030 (2)	0.0022 (19)	0.007 (2)	−0.004 (2)
N1	0.052 (2)	0.071 (3)	0.043 (3)	0.003 (2)	0.0102 (18)	−0.008 (2)
N2	0.041 (2)	0.072 (3)	0.057 (3)	0.0055 (18)	0.001 (2)	−0.007 (3)
O1	0.068 (2)	0.053 (2)	0.045 (2)	0.0031 (17)	0.0091 (18)	−0.0161 (19)
O2	0.070 (2)	0.062 (2)	0.042 (2)	0.0082 (16)	0.0097 (17)	−0.012 (2)

Geometric parameters (Å, º) top

C1—C2	1.379 (7)	C10—O1	1.405 (6)
C1—O1	1.381 (7)	C10—H10A	0.9700
C1—C6	1.404 (7)	C10—H10B	0.9700
C2—C3	1.370 (10)	C11—C16	1.388 (7)
C2—H2	0.9300	C11—C12	1.403 (6)
C3—C4	1.399 (9)	C12—C13	1.376 (7)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.347 (8)	C13—C14	1.383 (10)
C4—H4	0.9300	C13—H13	0.9300
C5—C6	1.406 (7)	C14—C15	1.365 (8)
C5—H5	0.9300	C14—H14	0.9300
C6—C7	1.433 (7)	C15—C16	1.381 (7)
C7—N1	1.271 (6)	C15—H15	0.9300
C7—C9	1.523 (6)	C16—C17	1.495 (7)
C8—O2	1.461 (6)	C17—H17A	0.9600
C8—C11	1.497 (6)	C17—H17B	0.9600
C8—C9	1.537 (6)	C17—H17C	0.9600
C8—H8	0.9800	C18—N2	1.131 (5)
C9—C18	1.487 (5)	N1—O2	1.410 (5)
C9—C10	1.512 (7)

C2—C1—O1	118.0 (5)	O1—C10—H10A	109.3
C2—C1—C6	120.6 (6)	C9—C10—H10A	109.3
O1—C1—C6	121.5 (4)	O1—C10—H10B	109.3
C3—C2—C1	119.8 (6)	C9—C10—H10B	109.3
C3—C2—H2	120.1	H10A—C10—H10B	108.0
C1—C2—H2	120.1	C16—C11—C12	119.8 (4)
C2—C3—C4	120.4 (5)	C16—C11—C8	121.2 (4)
C2—C3—H3	119.8	C12—C11—C8	118.9 (5)
C4—C3—H3	119.8	C13—C12—C11	120.5 (6)
C5—C4—C3	120.1 (6)	C13—C12—H12	119.8
C5—C4—H4	119.9	C11—C12—H12	119.8
C3—C4—H4	119.9	C12—C13—C14	119.5 (5)
C4—C5—C6	121.0 (6)	C12—C13—H13	120.3
C4—C5—H5	119.5	C14—C13—H13	120.3
C6—C5—H5	119.5	C15—C14—C13	119.6 (6)
C1—C6—C5	118.0 (5)	C15—C14—H14	120.2
C1—C6—C7	118.2 (5)	C13—C14—H14	120.2
C5—C6—C7	123.7 (5)	C14—C15—C16	122.5 (6)
N1—C7—C6	127.5 (4)	C14—C15—H15	118.7
N1—C7—C9	113.8 (4)	C16—C15—H15	118.7
C6—C7—C9	118.4 (4)	C15—C16—C11	118.0 (5)
O2—C8—C11	110.1 (4)	C15—C16—C17	119.9 (5)
O2—C8—C9	103.1 (4)	C11—C16—C17	122.1 (4)
C11—C8—C9	117.8 (4)	C16—C17—H17A	109.5
O2—C8—H8	108.5	C16—C17—H17B	109.5
C11—C8—H8	108.5	H17A—C17—H17B	109.5
C9—C8—H8	108.5	C16—C17—H17C	109.5
C18—C9—C10	109.7 (3)	H17A—C17—H17C	109.5
C18—C9—C7	108.9 (4)	H17B—C17—H17C	109.5
C10—C9—C7	107.6 (3)	N2—C18—C9	178.8 (5)
C18—C9—C8	113.6 (3)	C7—N1—O2	109.1 (4)
C10—C9—C8	117.3 (4)	C1—O1—C10	118.3 (4)
C7—C9—C8	98.7 (4)	N1—O2—C8	107.9 (3)
O1—C10—C9	111.5 (4)

O1—C1—C2—C3	179.9 (4)	C18—C9—C10—O1	62.9 (5)
C6—C1—C2—C3	0.4 (7)	C7—C9—C10—O1	−55.5 (4)
C1—C2—C3—C4	−0.8 (8)	C8—C9—C10—O1	−165.5 (4)
C2—C3—C4—C5	0.9 (8)	O2—C8—C11—C16	−140.8 (4)
C3—C4—C5—C6	−0.7 (7)	C9—C8—C11—C16	101.4 (5)
C2—C1—C6—C5	−0.2 (6)	O2—C8—C11—C12	42.6 (5)
O1—C1—C6—C5	−179.7 (4)	C9—C8—C11—C12	−75.2 (6)
C2—C1—C6—C7	177.9 (4)	C16—C11—C12—C13	−1.1 (7)
O1—C1—C6—C7	−1.5 (6)	C8—C11—C12—C13	175.5 (5)
C4—C5—C6—C1	0.3 (7)	C11—C12—C13—C14	−1.5 (8)
C4—C5—C6—C7	−177.7 (4)	C12—C13—C14—C15	2.6 (8)
C1—C6—C7—N1	163.8 (4)	C13—C14—C15—C16	−1.0 (9)
C5—C6—C7—N1	−18.2 (7)	C14—C15—C16—C11	−1.5 (7)
C1—C6—C7—C9	−10.4 (5)	C14—C15—C16—C17	179.5 (5)
C5—C6—C7—C9	167.6 (4)	C12—C11—C16—C15	2.6 (6)
N1—C7—C9—C18	103.9 (4)	C8—C11—C16—C15	−174.0 (4)
C6—C7—C9—C18	−81.1 (4)	C12—C11—C16—C17	−178.5 (5)
N1—C7—C9—C10	−137.2 (4)	C8—C11—C16—C17	5.0 (6)
C6—C7—C9—C10	37.8 (5)	C6—C7—N1—O2	−175.9 (4)
N1—C7—C9—C8	−14.8 (5)	C9—C7—N1—O2	−1.4 (5)
C6—C7—C9—C8	160.2 (4)	C2—C1—O1—C10	162.0 (4)
O2—C8—C9—C18	−91.3 (4)	C6—C1—O1—C10	−18.6 (6)
C11—C8—C9—C18	30.2 (7)	C9—C10—O1—C1	48.4 (5)
O2—C8—C9—C10	138.9 (4)	C7—N1—O2—C8	18.6 (4)
C11—C8—C9—C10	−99.6 (5)	C11—C8—O2—N1	−153.6 (3)
O2—C8—C9—C7	23.9 (4)	C9—C8—O2—N1	−27.1 (4)
C11—C8—C9—C7	145.4 (4)

Experimental details

Crystal data
Chemical formula	C₁₈H₁₄N₂O₂
M_r	290.31
Crystal system, space group	Orthorhombic, Pca2₁
Temperature (K)	298
a, b, c (Å)	19.326 (3), 10.7866 (17), 6.9072 (11)
V (Å³)	1439.9 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.35 × 0.25 × 0.15

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.970, 0.987
No. of measured, independent and observed [I > 2σ(I)] reflections	4742, 1750, 1100
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.653

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.146, 1.09
No. of reflections	1750
No. of parameters	200
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.17

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Acknowledgements

GS and SA thank the UGC, India, for financial support. GS thanks the SAIF, IIT-Madras, for the instrumentation facility.

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