Crystal structure of 2-methyl­amino-3-nitro-4-p-tolyl­pyrano[3,2-c]chromen-5(4H)-one

J Govindaraj; Y AaminaNaaz; Jayabal Kamalraja; Paramasivam T Perumal; A SubbiahPandi

doi:10.1107/S205698901500225X

. 2015 Feb 7;71(Pt 3):o158–o159. doi: 10.1107/S205698901500225X

Crystal structure of 2-methylamino-3-nitro-4-p-tolylpyrano[3,2-c]chromen-5(4H)-one

J Govindaraj ^a, Y AaminaNaaz ^b, Jayabal Kamalraja ^c, Paramasivam T Perumal ^c, A SubbiahPandi ^b,^*

PMCID: PMC4350753 PMID: 25844225

Abstract

In the racemic title compound, C₂₀H₁₆N₂O₅, the pyran ring adopts a shallow envelope conformation, with the stereogenic C atom displaced from the other atoms by 0.273 (2) Å. The dihedral angle between the fused-ring system and the pendant p-tolyl group is 87.62 (7)°. The molecular conformation is consolidated by an intramolecular N—H⋯O hydrogen bond, which generates an S(6) ring. In the crystal, molecules are linked by C—H⋯O interactions, resulting in [010] chains.

Keywords: crystal structure; pyrano[3,2-c]chromenone; biological activity; chromene derivatives; hydrogen bonding; crystal structure

Related literature

For background to the biological activity of chromene derivatives, see: Borges et al. (2005 ▸, 2009 ▸); Gibbs (2000 ▸); Varmus (2006 ▸). For a related structure, see: Narayanan et al. (2013 ▸). graphic file with name e-71-0o158-scheme1.jpg

Experimental

Crystal data

C₂₀H₁₆N₂O₅
M _r = 364.35
Monoclinic,
a = 10.8336 (11) Å
b = 11.7927 (11) Å
c = 13.7275 (14) Å
β = 108.357 (2)°
V = 1664.5 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 293 K
0.21 × 0.19 × 0.18 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ▸) T _min = 0.978, T _max = 0.981
28712 measured reflections
4571 independent reflections
2862 reflections with I > 2σ(I)
R _int = 0.039

Refinement

R[F ² > 2σ(F ²)] = 0.050
wR(F ²) = 0.151
S = 1.03
4571 reflections
244 parameters
H-atom parameters constrained
Δρ_max = 0.26 e Å⁻³
Δρ_min = −0.36 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 for Windows (Farrugia, 2012 ▸); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▸).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S205698901500225X/hb7345sup1.cif

e-71-0o158-sup1.cif^{(20.9KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S205698901500225X/hb7345Isup2.hkl

e-71-0o158-Isup2.hkl^{(224KB, hkl)}

Click here for additional data file.^{(6.8KB, cml)}

Supporting information file. DOI: 10.1107/S205698901500225X/hb7345Isup3.cml

Click here for additional data file.^{(1.2MB, tif)}

. DOI: 10.1107/S205698901500225X/hb7345fig1.tif

The molecular structure of the title molecule, with atom displacement ellipsoids drawn at the 30% probability level. The intramolecular N—H⋯O hydrogen bond, which generates an S(6) ring motif, is shown as a dashed line.

Click here for additional data file.^{(1.9MB, tif)}

b C . DOI: 10.1107/S205698901500225X/hb7345fig2.tif

The crystal packing of the title compound, viewed along the b axis, showing C9—H9C⋯O4 hydrogen bonds producing chains parallel to the 101 planes.

CCDC reference: 1046918

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
N1H1O5	0.86	1.96	2.590(2)	129
C9H9CO4ⁱ	0.96	2.46	3.389(3)	163

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Symmetry code: (i) Inline graphic .

Acknowledgments

The authors thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the data collection.

supplementary crystallographic information

S1. Comment

Coumarins and their natural synthetic derivatives are pharmacologically interesting compounds due to their structural diversity and synthetic accessibility (Borges et al., 2005, 2009). Cancer, a diverse group of diseases characterized by uncontrolled growth of abnormal cells, is a major worldwide problem. It is a fatal disease standing next to the cardiovascular disease in terms of morbidity and mortality. Although the cancer research has led to a number of new and effective solutions, the medicines used as treatments have clear limitations and unfortunately cancer is projected as the primary cause of death in the future(Gibbs et al. 2000; Varmus et al. 2006).

The title compound, Fig. 1, consists of a chromene moiety attached to a nitrophenyl ring, a nitro group and a methylamine group. The molecular structure is stabilized by an intra molecular N1—H1A···O5 interaction, which generates an S(6) ring motif. The chromen ring is almost coplanar with the least-square planes of the phenyl ring, making dihedral angle of 87.18 (8)°. The six-membered pyran ring(C7/O1/C8/C10/C11/C12) adopts sofa conformatons, with puckering parameters Q₂ = 0.1787 (17) Å, Q₃ = -0.0688 (18) Å and φ₂ = 0.9 (6)°, respectively. The C18 atom deviates from mean plane of the phenyl ring by -0.0260 Å. The title compound exihibits structural similarities with an already reported related structure (Narayanan et al. 2013).

In the crystal, the molecules are linked via intermolecular C9—H9C···O4 hydrogen-bond interaction to generate [010] chains.

S2. Experimental

A solution of 4-methylbenzaldehyde (1.0 mmol), 4-hydroxycoumarin (1.0 mmol), NMSM (1.0 mmol), and piperidine (0.2 equiv) in EtOH (2 ml) was stirred for the three hours. After reaction was complete as indicated by TLC, the product was filtered and washed with EtOH (2 ml) to remove the excess base and other impurities. Finally, the product was recrystallized from EtOH to yield colourless blocks of the title compound.