8,8-Dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione

Srinivasan, T.; Yuvaraj, P.; Reddy, B.S.R.; Velmurugan, D.

doi:10.1107/S1600536813001050

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 69| Part 2| February 2013| Page o254

doi:10.1107/S1600536813001050

Open

access

8,8-Dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione

Thothadri Srinivasan,^a Panneerselvam Yuvaraj,^b Boreddy S. R. Reddy ^b and Devadasan Velmurugan ^a ^*

^aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and ^bIndustrial Chemistry Laboratory, Central Leather Research Institute, Adyar, Chennai 600 020, India
^*Correspondence e-mail: shirai2011@gmail.com

(Received 4 January 2013; accepted 11 January 2013; online 19 January 2013)

In the title compound, C₁₈H₁₅NO₃, the fused benzopyran and pyridine rings are essentially coplanar [r.m.s. deviation = 0.0533 Å with a maximum deviation of 0.080 (1) Å for a benzene C atom]. The cyclohexanone ring adopts an envelope conformation with the dimethyl-substituted C atom 0.660 (2) Å out of the plane formed by the remaining ring atoms (r.m.s. deviation = 0.0305 Å). The dihedral angle between the mean planes of the pyran and cyclohexanone rings is 12.95 (6)°. In the crystal, molecules are linked via C—H⋯O hydrogen bonds, leading to chains running along [011].

Related literature

For the uses and biological importance of diketones, see: Bennett et al. (1999 ); Sato et al. (2008 ). For a related structure, see: Öztürk Yildirim et al. (2012).

Experimental

Crystal data

C₁₈H₁₅NO₃
M_r = 293.31
Triclinic, $[P \overline 1]$
a = 7.4426 (6) Å
b = 10.5117 (9) Å
c = 10.6887 (9) Å
α = 60.939 (4)°
β = 88.107 (5)°
γ = 77.546 (5)°
V = 711.22 (10) Å³
Z = 2
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.30 × 0.25 × 0.20 mm

Data collection

Bruker SMART APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.972, T_max = 0.982
10655 measured reflections
2949 independent reflections
2427 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.118
S = 1.05
2949 reflections
201 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C15—H15⋯O2ⁱ	0.93	2.43	3.250 (2)	147
Symmetry code: (i) x-1, y+1, z-1.

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 global, I. DOI: 10.1107/S1600536813001050/pv2617sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813001050/pv2617Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813001050/pv2617Isup3.cml

checkCIF report

Comment top

Diketones are key intermediates in the preparation of various heterocyclic compounds (Sato et al., 2008) and are popular in organic synthesis for their applications in biology and medicine. They are known to exhibit antioxidant, antitumour and antibacterial activities (Bennett et al., 1999).

The bond distances and angles in the title compound (Fig. 1) agree very well with the corresponding bond distances and angles reported in a closely related compound (Öztürk Yildirim et al., 2012). The dihedral angle between the pyran ring (O3/C1/C2/C10/C11/C12) and the pyridine ring (N1/C2/C3/C4/C9/C10) is 3.08 (6)°. The dihedral angle between the pyran ring and the benzene ring (C11-C16) is 2.70 (6)°. Moreover, pyridine ring makes a diheral angle of 5.78 (6)° with the benzene ring (C11-C16). The dihedral angle between the pyran ring and the cyclohexanone ring is 12.95 (6)°. In the crystal, molecules are linked via C15–H15···O2 hydrogen bonding interactions leading to chains running along the b-axis (Table 1 & Fig. 2).

Related literature top

For the uses and biological importance of diketones, see: Bennett et al. (1999); Sato et al. (2008). For a related structure, see: Öztürk Yildirim et al. (2012).

Experimental top

2-Amino-4-oxo-4H-chromene-3-carbaldehyde (100 mg, 1.0 mmol) was reacted with 5,5-dimethylcyclohexane-1,3-dione (88 mg, 1.2 mmol) in the presence of yeterbium triflate (Yb(oft)3) (98 mg, 0.3 mmol) after stirring. All these reactants were dissolved in xylene (5 ml). The reaction mixture was refluxed at 398 K for 12 hours. The reaction mixture was extracted with ethyl acetate/hexane (40:60 v/v). The completion of the reaction was monitored by TLC. The end product was the title compound which was purified by column chromatography (ethyl acetate/hexane, 40:60), the yield being 80%. Single 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, showing displacement ellipsoids drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.
	Fig. 2. The crystal packing of the title compound viewed down a axis. H-atoms not involved in H-bonds have been excluded for clarity.

8,8-Dimethyl-8,9-dihydro-7H-chromeno[2,3-b]quinoline-10,12-dione top

Crystal data top

C₁₈H₁₅NO₃	Z = 2
M_r = 293.31	F(000) = 308
Triclinic, P1	D_x = 1.370 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.4426 (6) Å	Cell parameters from 2949 reflections
b = 10.5117 (9) Å	θ = 2.2–26.5°
c = 10.6887 (9) Å	µ = 0.09 mm⁻¹
α = 60.939 (4)°	T = 293 K
β = 88.107 (5)°	Block, colourless
γ = 77.546 (5)°	0.30 × 0.25 × 0.20 mm
V = 711.22 (10) Å³

Data collection top

Bruker SMART APEXII area-detector diffractometer	2949 independent reflections
Radiation source: fine-focus sealed tube	2427 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ω and ϕ scans	θ_max = 26.5°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −9→9
T_min = 0.972, T_max = 0.982	k = −13→13
10655 measured reflections	l = −13→13

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.118	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0598P)² + 0.1006P] where P = (F_o² + 2F_c²)/3
2949 reflections	(Δ/σ)_max < 0.001
201 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₈H₁₅NO₃	γ = 77.546 (5)°
M_r = 293.31	V = 711.22 (10) Å³
Triclinic, P1	Z = 2
a = 7.4426 (6) Å	Mo Kα radiation
b = 10.5117 (9) Å	µ = 0.09 mm⁻¹
c = 10.6887 (9) Å	T = 293 K
α = 60.939 (4)°	0.30 × 0.25 × 0.20 mm
β = 88.107 (5)°

Data collection top

Bruker SMART APEXII area-detector diffractometer	2949 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2427 reflections with I > 2σ(I)
T_min = 0.972, T_max = 0.982	R_int = 0.031
10655 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.118	H-atom parameters constrained
S = 1.05	Δρ_max = 0.17 e Å⁻³
2949 reflections	Δρ_min = −0.22 e Å⁻³
201 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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	0.01482 (17)	0.15363 (14)	0.17863 (13)	0.0415 (3)
C2	0.05259 (16)	0.17700 (13)	0.29891 (12)	0.0375 (3)
C3	0.17358 (16)	0.07117 (13)	0.41692 (12)	0.0388 (3)
H3	0.2332	−0.0190	0.4224	0.047*
C4	0.20560 (16)	0.09954 (13)	0.52620 (12)	0.0382 (3)
C5	0.33905 (17)	−0.01133 (14)	0.65130 (13)	0.0431 (3)
C6	0.37866 (19)	0.03085 (15)	0.76134 (13)	0.0485 (3)
H6A	0.5082	−0.0106	0.7958	0.058*
H6B	0.3072	−0.0154	0.8423	0.058*
C7	0.33647 (18)	0.19874 (14)	0.70916 (13)	0.0469 (3)
C8	0.13932 (19)	0.26760 (16)	0.63542 (14)	0.0518 (3)
H8A	0.0525	0.2290	0.7066	0.062*
H8B	0.1136	0.3750	0.5966	0.062*
C9	0.10985 (16)	0.23518 (13)	0.51692 (12)	0.0406 (3)
C10	−0.03248 (16)	0.30872 (13)	0.29978 (13)	0.0387 (3)
C11	−0.18038 (16)	0.41066 (14)	0.06841 (12)	0.0405 (3)
C12	−0.10695 (16)	0.28199 (14)	0.05958 (13)	0.0410 (3)
C13	−0.15013 (18)	0.28050 (16)	−0.06622 (13)	0.0488 (3)
H13	−0.1045	0.1951	−0.0738	0.059*
C14	−0.2593 (2)	0.40430 (17)	−0.17835 (14)	0.0542 (4)
H14	−0.2865	0.4028	−0.2618	0.065*
C15	−0.32914 (18)	0.53168 (16)	−0.16751 (14)	0.0523 (3)
H15	−0.4027	0.6152	−0.2441	0.063*
C16	−0.29078 (18)	0.53585 (15)	−0.04437 (14)	0.0481 (3)
H16	−0.3382	0.6213	−0.0372	0.058*
C17	0.3488 (2)	0.22292 (19)	0.83847 (16)	0.0643 (4)
H17A	0.4726	0.1818	0.8832	0.096*
H17B	0.2653	0.1741	0.9063	0.096*
H17C	0.3161	0.3280	0.8070	0.096*
C18	0.4756 (2)	0.27038 (17)	0.60480 (16)	0.0608 (4)
H18A	0.5975	0.2276	0.6532	0.091*
H18B	0.4458	0.3761	0.5704	0.091*
H18C	0.4711	0.2525	0.5251	0.091*
N1	−0.00885 (14)	0.33841 (12)	0.40449 (11)	0.0440 (3)
O1	0.08122 (15)	0.03625 (11)	0.17871 (10)	0.0603 (3)
O2	0.40972 (15)	−0.13281 (11)	0.66438 (11)	0.0630 (3)
O3	−0.14882 (12)	0.42254 (9)	0.18821 (9)	0.0467 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0459 (7)	0.0410 (7)	0.0389 (6)	−0.0114 (5)	0.0027 (5)	−0.0201 (5)
C2	0.0396 (6)	0.0378 (6)	0.0357 (6)	−0.0107 (5)	0.0034 (5)	−0.0178 (5)
C3	0.0403 (6)	0.0353 (6)	0.0399 (6)	−0.0082 (5)	0.0029 (5)	−0.0180 (5)
C4	0.0397 (6)	0.0375 (6)	0.0357 (6)	−0.0092 (5)	0.0016 (5)	−0.0164 (5)
C5	0.0449 (7)	0.0393 (7)	0.0391 (6)	−0.0088 (5)	−0.0003 (5)	−0.0149 (5)
C6	0.0535 (7)	0.0471 (7)	0.0373 (6)	−0.0078 (6)	−0.0067 (5)	−0.0157 (6)
C7	0.0558 (8)	0.0474 (7)	0.0386 (6)	−0.0082 (6)	−0.0045 (5)	−0.0229 (6)
C8	0.0595 (8)	0.0523 (8)	0.0439 (7)	0.0013 (6)	−0.0055 (6)	−0.0288 (6)
C9	0.0423 (6)	0.0415 (6)	0.0364 (6)	−0.0067 (5)	0.0011 (5)	−0.0190 (5)
C10	0.0378 (6)	0.0391 (6)	0.0365 (6)	−0.0066 (5)	0.0005 (5)	−0.0173 (5)
C11	0.0392 (6)	0.0464 (7)	0.0349 (6)	−0.0116 (5)	0.0018 (5)	−0.0186 (5)
C12	0.0429 (6)	0.0448 (7)	0.0359 (6)	−0.0150 (5)	0.0038 (5)	−0.0182 (5)
C13	0.0546 (8)	0.0542 (8)	0.0405 (7)	−0.0157 (6)	0.0023 (6)	−0.0239 (6)
C14	0.0587 (8)	0.0662 (9)	0.0370 (7)	−0.0182 (7)	−0.0020 (6)	−0.0227 (6)
C15	0.0487 (7)	0.0557 (8)	0.0383 (7)	−0.0090 (6)	−0.0044 (5)	−0.0130 (6)
C16	0.0462 (7)	0.0462 (7)	0.0431 (7)	−0.0060 (6)	−0.0022 (5)	−0.0167 (6)
C17	0.0774 (10)	0.0703 (10)	0.0496 (8)	−0.0050 (8)	−0.0112 (7)	−0.0366 (8)
C18	0.0758 (10)	0.0598 (9)	0.0538 (8)	−0.0271 (8)	0.0013 (7)	−0.0283 (7)
N1	0.0480 (6)	0.0430 (6)	0.0397 (5)	−0.0025 (5)	−0.0026 (4)	−0.0221 (5)
O1	0.0808 (7)	0.0487 (6)	0.0534 (6)	−0.0004 (5)	−0.0115 (5)	−0.0312 (5)
O2	0.0751 (7)	0.0440 (6)	0.0594 (6)	0.0067 (5)	−0.0183 (5)	−0.0241 (5)
O3	0.0520 (5)	0.0431 (5)	0.0398 (5)	0.0021 (4)	−0.0087 (4)	−0.0208 (4)

Geometric parameters (Å, º) top

C1—O1	1.2259 (15)	C9—N1	1.3386 (15)
C1—C12	1.4635 (17)	C10—N1	1.3256 (15)
C1—C2	1.4672 (16)	C10—O3	1.3559 (14)
C2—C3	1.3854 (16)	C11—O3	1.3778 (14)
C2—C10	1.3971 (17)	C11—C16	1.3849 (17)
C3—C4	1.3775 (16)	C11—C12	1.3924 (18)
C3—H3	0.9300	C12—C13	1.4010 (17)
C4—C9	1.4070 (17)	C13—C14	1.3723 (19)
C4—C5	1.4857 (16)	C13—H13	0.9300
C5—O2	1.2118 (15)	C14—C15	1.387 (2)
C5—C6	1.5009 (17)	C14—H14	0.9300
C6—C7	1.5299 (19)	C15—C16	1.3792 (18)
C6—H6A	0.9700	C15—H15	0.9300
C6—H6B	0.9700	C16—H16	0.9300
C7—C18	1.526 (2)	C17—H17A	0.9600
C7—C17	1.5308 (17)	C17—H17B	0.9600
C7—C8	1.5369 (18)	C17—H17C	0.9600
C8—C9	1.4963 (17)	C18—H18A	0.9600
C8—H8A	0.9700	C18—H18B	0.9600
C8—H8B	0.9700	C18—H18C	0.9600

O1—C1—C12	123.35 (11)	N1—C10—O3	112.77 (10)
O1—C1—C2	122.30 (11)	N1—C10—C2	125.36 (11)
C12—C1—C2	114.34 (10)	O3—C10—C2	121.86 (10)
C3—C2—C10	116.41 (11)	O3—C11—C16	115.67 (11)
C3—C2—C1	122.35 (11)	O3—C11—C12	122.82 (11)
C10—C2—C1	121.25 (11)	C16—C11—C12	121.51 (11)
C4—C3—C2	119.96 (11)	C11—C12—C13	118.32 (12)
C4—C3—H3	120.0	C11—C12—C1	120.13 (11)
C2—C3—H3	120.0	C13—C12—C1	121.55 (12)
C3—C4—C9	118.78 (10)	C14—C13—C12	120.39 (13)
C3—C4—C5	120.42 (11)	C14—C13—H13	119.8
C9—C4—C5	120.79 (10)	C12—C13—H13	119.8
O2—C5—C4	120.40 (11)	C13—C14—C15	120.18 (12)
O2—C5—C6	121.68 (11)	C13—C14—H14	119.9
C4—C5—C6	117.90 (11)	C15—C14—H14	119.9
C5—C6—C7	115.45 (10)	C16—C15—C14	120.73 (12)
C5—C6—H6A	108.4	C16—C15—H15	119.6
C7—C6—H6A	108.4	C14—C15—H15	119.6
C5—C6—H6B	108.4	C15—C16—C11	118.85 (13)
C7—C6—H6B	108.4	C15—C16—H16	120.6
H6A—C6—H6B	107.5	C11—C16—H16	120.6
C18—C7—C6	110.08 (12)	C7—C17—H17A	109.5
C18—C7—C17	109.31 (11)	C7—C17—H17B	109.5
C6—C7—C17	109.11 (11)	H17A—C17—H17B	109.5
C18—C7—C8	110.61 (11)	C7—C17—H17C	109.5
C6—C7—C8	108.18 (11)	H17A—C17—H17C	109.5
C17—C7—C8	109.53 (11)	H17B—C17—H17C	109.5
C9—C8—C7	113.02 (11)	C7—C18—H18A	109.5
C9—C8—H8A	109.0	C7—C18—H18B	109.5
C7—C8—H8A	109.0	H18A—C18—H18B	109.5
C9—C8—H8B	109.0	C7—C18—H18C	109.5
C7—C8—H8B	109.0	H18A—C18—H18C	109.5
H8A—C8—H8B	107.8	H18B—C18—H18C	109.5
N1—C9—C4	122.22 (11)	C10—N1—C9	117.23 (10)
N1—C9—C8	117.88 (11)	C10—O3—C11	119.42 (10)
C4—C9—C8	119.90 (11)

O1—C1—C2—C3	3.61 (19)	C1—C2—C10—N1	178.92 (10)
C12—C1—C2—C3	−176.04 (10)	C3—C2—C10—O3	177.77 (10)
O1—C1—C2—C10	−176.52 (12)	C1—C2—C10—O3	−2.11 (18)
C12—C1—C2—C10	3.83 (16)	O3—C11—C12—C13	178.89 (10)
C10—C2—C3—C4	−0.61 (16)	C16—C11—C12—C13	−1.16 (18)
C1—C2—C3—C4	179.27 (10)	O3—C11—C12—C1	−2.24 (18)
C2—C3—C4—C9	1.67 (17)	C16—C11—C12—C1	177.71 (11)
C2—C3—C4—C5	−178.27 (10)	O1—C1—C12—C11	178.63 (12)
C3—C4—C5—O2	−6.06 (18)	C2—C1—C12—C11	−1.73 (16)
C9—C4—C5—O2	174.00 (12)	O1—C1—C12—C13	−2.54 (19)
C3—C4—C5—C6	175.48 (10)	C2—C1—C12—C13	177.10 (10)
C9—C4—C5—C6	−4.47 (17)	C11—C12—C13—C14	1.21 (19)
O2—C5—C6—C7	159.80 (13)	C1—C12—C13—C14	−177.64 (11)
C4—C5—C6—C7	−21.76 (17)	C12—C13—C14—C15	−0.5 (2)
C5—C6—C7—C18	−70.62 (14)	C13—C14—C15—C16	−0.2 (2)
C5—C6—C7—C17	169.43 (11)	C14—C15—C16—C11	0.3 (2)
C5—C6—C7—C8	50.34 (15)	O3—C11—C16—C15	−179.63 (10)
C18—C7—C8—C9	65.43 (15)	C12—C11—C16—C15	0.42 (19)
C6—C7—C8—C9	−55.20 (15)	O3—C10—N1—C9	−177.28 (10)
C17—C7—C8—C9	−174.03 (12)	C2—C10—N1—C9	1.78 (18)
C3—C4—C9—N1	−1.11 (18)	C4—C9—N1—C10	−0.57 (18)
C5—C4—C9—N1	178.84 (10)	C8—C9—N1—C10	179.47 (11)
C3—C4—C9—C8	178.85 (11)	N1—C10—O3—C11	177.09 (9)
C5—C4—C9—C8	−1.21 (17)	C2—C10—O3—C11	−2.00 (17)
C7—C8—C9—N1	−147.69 (12)	C16—C11—O3—C10	−175.71 (10)
C7—C8—C9—C4	32.35 (17)	C12—C11—O3—C10	4.23 (17)
C3—C2—C10—N1	−1.20 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O2ⁱ	0.93	2.43	3.250 (2)	147

Symmetry code: (i) x−1, y+1, z−1.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₅NO₃
M_r	293.31
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.4426 (6), 10.5117 (9), 10.6887 (9)
α, β, γ (°)	60.939 (4), 88.107 (5), 77.546 (5)
V (Å³)	711.22 (10)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Bruker SMART APEXII area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.972, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	10655, 2949, 2427
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.628

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.118, 1.05
No. of reflections	2949
No. of parameters	201
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.22

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C15—H15···O2ⁱ	0.93	2.43	3.250 (2)	147

Symmetry code: (i) x−1, y+1, z−1.

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. TS also thanks the DST for an Inspire fellowship.

References

Bennett, I., Broom, N. J. P., Cassels, R., Elder, J. S., Masson, N. D. & O'Hanlon, P. J. (1999). Bioorg. Med. Chem. Lett. 9, 1847–1852. Web of Science CrossRef PubMed CAS Google Scholar
Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Öztürk Yildirim, S., Butcher, R. J., El-Khouly, A., Safak, C. & Şimsek, R. (2012). Acta Cryst. E68, o3365–o3366. CSD CrossRef IUCr Journals Google Scholar
Sato, K., Yamazoe, S., Yamamoto, R., Ohata, S., Tarui, A., Omote, M., Kumadaki, I. & Ando, A. (2008). Org. Lett. 10, 2405–2408. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar