3-[2-(5H-Indolo[2,3-b]quinoxalin-5-yl)eth­yl]-1,3-oxazolidin-2-one

Alsubari, A.; Bouhfid, R.; Zouihri, H.; Essassi, E.M.; Ng, S.W.

doi:10.1107/S1600536810033222

organic compounds

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ISSN: 2056-9890

Volume 66| Part 9| September 2010| Page o2461

https://doi.org/10.1107/S1600536810033222

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3-[2-(5H-Indolo[2,3-b]quinoxalin-5-yl)ethyl]-1,3-oxazolidin-2-one

Abdussalam Alsubari,^a Rachid Bouhfid,^a Hafid Zouihri,^b El Mokhtar Essassi ^a and Seik Weng Ng ^c ^*

^aLaboratoire de Chimie Organique Hétérocyclique, Pôle de Compétences Pharmacochimie, Université Mohammed V-Agdal, BP 1014 Avenue Ibn Batout, Rabat, Morocco, ^bCNRST Division UATRS, Angle Allal Fassi/FAR, BP 8027 Hay Riad, Rabat, Morocco, and ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 21 July 2010; accepted 18 August 2010; online 28 August 2010)

The title compound, C₁₉H₁₆N₄O₂, has an almost planar fused N-heterocyclic system (r.m.s. deviation = 0.031 Å) and an almost planar five-membered 1,3-oxazolidine ring (r.m.s. deviation = 0.015 Å) at the ends of an ethylene chain [N—C—C—N torsion angle = −65.6 (2)°]. The ring systems are inclined at 38.1 (1)° to one another.

Related literature

For background to this class of oxindole derivatives, see: Alsubari et al. (2009 ). For a related structure, see: Alsubari et al. (2010 )

Experimental

Crystal data

C₁₉H₁₆N₄O₂
M_r = 332.36
Monoclinic, P 2₁ /n
a = 14.5565 (4) Å
b = 5.8993 (2) Å
c = 18.6434 (6) Å
β = 92.393 (2)°
V = 1599.57 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.37 × 0.18 × 0.17 mm

Data collection

Bruker X8 APEXII diffractometer
19296 measured reflections
3216 independent reflections
1897 reflections with I > 2σ(I)
R_int = 0.054

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.152
S = 0.95
3216 reflections
226 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.15 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: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810033222/fl2310sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810033222/fl2310Isup2.hkl

checkCIF report

Comment top

The synthesis of new oxindole derivatives having an oxazolindin-2-one unit has been detailed in a recent report (Alsubari et al., 2009). Among related compounds whose structures have been determined is 3-[2-(2,3-dioxoindolin-1-yl)ethyl]-1,3-oxazolidin-2-one (Alsubari et al., 2010) in which the oxazolidinyl ring has an envelope conformation with the methylene C atom bonded to the N atom as the flap. The –CH₂–CH₂– connecting this ring to the other fused-ring system has its substituents in a gauche conformation [torsion angle = 62.7 (2)°]. In the tite compound (Scheme I, Fig. 1), the oxazolidinyl ring is planar (rms 0.015 Å), and there is no indication of any disorder in the ethylene portion of the ring. The fused N-heterocyclic system (rms 0.031 Å) is also planar and the two ring systems are inclined at 38.1 (1)° to one another. . The fused-rings are not stacked directly over one another, however, the distance between two inversion-related fused ring systems is only 3.4 Å (Fig. 2).

Related literature top

For background to this class of oxindole derivatives, see: Alsubari et al. (2009). For a related structure, see: Alsubari et al. (2010)

Experimental top

1-(2-(2-Oxoxazolidin-3-yl)ethyl)indoline-2,3-dione (0.5 g, 3.84 mmole) and o-phenylenediamine (0.41 g, 3.84 mmole) were heated in xylene (30 ml) and refluxed for twelve hours. The solvent was then removed under reduced pressure and the residue recrystallized from ethanol to afford the title compound as yellow crystals.

Structure description top

For background to this class of oxindole derivatives, see: Alsubari et al. (2009). For a related structure, see: Alsubari et al. (2010)

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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. Thermal ellipsoid plot of the title compound at the 50% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.
	Fig. 2. Two molecules disposed about a center-of-inversion.

3-[2-(5H-Indolo[2,3-b]quinoxalin-5-yl)ethyl]-1,3-oxazolidin-2-one top

Crystal data top

C₁₉H₁₆N₄O₂	F(000) = 696
M_r = 332.36	D_x = 1.380 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2575 reflections
a = 14.5565 (4) Å	θ = 2.8–21.3°
b = 5.8993 (2) Å	µ = 0.09 mm⁻¹
c = 18.6434 (6) Å	T = 293 K
β = 92.393 (2)°	Prism, yellow
V = 1599.57 (9) Å³	0.37 × 0.18 × 0.17 mm
Z = 4

Data collection top

Bruker X8 APEXII diffractometer	1897 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.054
Graphite monochromator	θ_max = 26.3°, θ_min = 2.8°
φ and ω scans	h = −18→18
19296 measured reflections	k = −7→7
3216 independent reflections	l = −23→23

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.152	H-atom parameters constrained
S = 0.95	w = 1/[σ²(F_o²) + (0.0947P)²] where P = (F_o² + 2F_c²)/3
3216 reflections	(Δ/σ)_max = 0.001
226 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.15 e Å⁻³

Crystal data top

C₁₉H₁₆N₄O₂	V = 1599.57 (9) Å³
M_r = 332.36	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 14.5565 (4) Å	µ = 0.09 mm⁻¹
b = 5.8993 (2) Å	T = 293 K
c = 18.6434 (6) Å	0.37 × 0.18 × 0.17 mm
β = 92.393 (2)°

Data collection top

Bruker X8 APEXII diffractometer	1897 reflections with I > 2σ(I)
19296 measured reflections	R_int = 0.054
3216 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.152	H-atom parameters constrained
S = 0.95	Δρ_max = 0.22 e Å⁻³
3216 reflections	Δρ_min = −0.15 e Å⁻³
226 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.14976 (14)	0.4457 (3)	0.30554 (10)	0.0756 (6)
O2	0.09479 (13)	0.3291 (3)	0.41022 (10)	0.0765 (6)
N1	0.38685 (12)	0.2701 (3)	0.50246 (9)	0.0499 (5)
N2	0.32451 (12)	0.6823 (3)	0.43058 (9)	0.0493 (5)
N3	0.21587 (12)	0.6899 (3)	0.52289 (9)	0.0491 (5)
N4	0.10754 (12)	0.7065 (3)	0.38211 (9)	0.0449 (4)
C1	0.42821 (14)	0.3536 (4)	0.44272 (11)	0.0455 (5)
C2	0.50363 (16)	0.2364 (4)	0.41630 (12)	0.0536 (6)
H2	0.5235	0.1027	0.4383	0.064*
C3	0.54794 (16)	0.3169 (4)	0.35861 (12)	0.0571 (6)
H3	0.5980	0.2382	0.3418	0.069*
C4	0.51867 (16)	0.5176 (4)	0.32443 (12)	0.0573 (6)
H4	0.5496	0.5713	0.2852	0.069*
C5	0.44540 (15)	0.6342 (4)	0.34824 (12)	0.0519 (6)
H5	0.4262	0.7664	0.3249	0.062*
C6	0.39828 (14)	0.5568 (4)	0.40790 (10)	0.0434 (5)
C7	0.28851 (14)	0.5993 (4)	0.48773 (11)	0.0448 (5)
C8	0.31888 (14)	0.3950 (4)	0.52400 (11)	0.0446 (5)
C9	0.26054 (15)	0.3687 (4)	0.58425 (11)	0.0477 (5)
C10	0.25656 (16)	0.2117 (4)	0.64019 (12)	0.0593 (6)
H10	0.2985	0.0928	0.6437	0.071*
C11	0.19041 (17)	0.2347 (5)	0.68979 (14)	0.0693 (7)
H11	0.1874	0.1309	0.7272	0.083*
C12	0.12790 (18)	0.4118 (5)	0.68458 (13)	0.0713 (8)
H12	0.0829	0.4229	0.7184	0.086*
C13	0.13042 (17)	0.5719 (5)	0.63082 (12)	0.0624 (7)
H13	0.0884	0.6907	0.6282	0.075*
C14	0.19776 (15)	0.5498 (4)	0.58088 (11)	0.0480 (6)
C15	0.15862 (15)	0.8786 (4)	0.49739 (11)	0.0505 (6)
H15A	0.1961	0.9839	0.4714	0.061*
H15B	0.1353	0.9582	0.5384	0.061*
C16	0.07797 (15)	0.8028 (4)	0.44871 (12)	0.0483 (6)
H16A	0.0424	0.6908	0.4737	0.058*
H16B	0.0384	0.9317	0.4381	0.058*
C17	0.11498 (16)	0.4834 (4)	0.37101 (13)	0.0539 (6)
C18	0.1696 (2)	0.6593 (5)	0.27265 (14)	0.0742 (8)
H18A	0.1341	0.6763	0.2278	0.089*
H18B	0.2344	0.6699	0.2630	0.089*
C19	0.14339 (19)	0.8400 (4)	0.32542 (12)	0.0616 (7)
H19A	0.1965	0.9276	0.3421	0.074*
H19B	0.0971	0.9416	0.3046	0.074*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.1126 (15)	0.0451 (11)	0.0699 (11)	0.0048 (9)	0.0125 (11)	−0.0150 (8)
O2	0.0993 (14)	0.0362 (10)	0.0947 (14)	−0.0026 (9)	0.0106 (11)	0.0101 (9)
N1	0.0567 (11)	0.0489 (11)	0.0437 (10)	0.0008 (9)	−0.0010 (9)	0.0018 (8)
N2	0.0515 (11)	0.0515 (11)	0.0446 (10)	0.0010 (9)	0.0001 (9)	0.0027 (8)
N3	0.0496 (11)	0.0537 (12)	0.0442 (10)	0.0081 (9)	0.0031 (9)	0.0015 (8)
N4	0.0569 (11)	0.0318 (10)	0.0459 (10)	0.0031 (8)	−0.0002 (8)	−0.0013 (8)
C1	0.0486 (12)	0.0489 (13)	0.0387 (11)	−0.0020 (10)	−0.0038 (10)	−0.0051 (9)
C2	0.0602 (14)	0.0534 (14)	0.0467 (13)	0.0070 (11)	−0.0034 (11)	−0.0031 (11)
C3	0.0562 (14)	0.0647 (16)	0.0507 (14)	0.0115 (12)	0.0040 (11)	−0.0073 (12)
C4	0.0571 (15)	0.0726 (17)	0.0426 (12)	−0.0010 (13)	0.0062 (11)	−0.0009 (12)
C5	0.0539 (13)	0.0558 (15)	0.0460 (12)	0.0022 (11)	0.0012 (11)	0.0057 (11)
C6	0.0434 (12)	0.0499 (13)	0.0366 (11)	0.0014 (10)	−0.0034 (9)	−0.0038 (9)
C7	0.0471 (12)	0.0466 (13)	0.0401 (11)	−0.0011 (10)	−0.0041 (10)	−0.0004 (10)
C8	0.0462 (12)	0.0438 (13)	0.0430 (11)	−0.0005 (10)	−0.0072 (10)	−0.0009 (10)
C9	0.0466 (12)	0.0526 (14)	0.0436 (12)	−0.0055 (10)	−0.0022 (10)	0.0002 (10)
C10	0.0585 (14)	0.0619 (16)	0.0573 (15)	−0.0005 (12)	−0.0025 (12)	0.0096 (12)
C11	0.0661 (16)	0.083 (2)	0.0587 (16)	−0.0056 (15)	0.0070 (13)	0.0199 (14)
C12	0.0602 (16)	0.102 (2)	0.0523 (14)	−0.0002 (16)	0.0111 (12)	0.0145 (15)
C13	0.0573 (15)	0.0779 (18)	0.0524 (14)	0.0068 (13)	0.0057 (12)	0.0027 (13)
C14	0.0483 (13)	0.0553 (14)	0.0401 (11)	−0.0023 (10)	−0.0031 (10)	0.0013 (10)
C15	0.0596 (14)	0.0442 (13)	0.0479 (13)	0.0055 (10)	0.0024 (11)	−0.0064 (10)
C16	0.0494 (12)	0.0401 (13)	0.0558 (13)	0.0085 (10)	0.0059 (10)	0.0024 (10)
C17	0.0604 (15)	0.0371 (13)	0.0639 (15)	0.0037 (10)	−0.0018 (12)	−0.0045 (11)
C18	0.104 (2)	0.0604 (18)	0.0588 (16)	−0.0010 (14)	0.0136 (15)	−0.0080 (12)
C19	0.0917 (18)	0.0481 (15)	0.0453 (13)	0.0035 (13)	0.0039 (12)	0.0037 (10)

Geometric parameters (Å, º) top

O1—C17	1.359 (3)	C7—C8	1.442 (3)
O1—C18	1.436 (3)	C8—C9	1.445 (3)
O2—C17	1.211 (3)	C9—C10	1.398 (3)
N1—C8	1.310 (3)	C9—C14	1.406 (3)
N1—C1	1.379 (3)	C10—C11	1.369 (3)
N2—C7	1.302 (3)	C10—H10	0.9300
N2—C6	1.385 (3)	C11—C12	1.386 (4)
N3—C7	1.375 (3)	C11—H11	0.9300
N3—C14	1.395 (3)	C12—C13	1.379 (3)
N3—C15	1.458 (3)	C12—H12	0.9300
N4—C17	1.338 (3)	C13—C14	1.386 (3)
N4—C19	1.434 (3)	C13—H13	0.9300
N4—C16	1.447 (3)	C15—C16	1.521 (3)
C1—C2	1.404 (3)	C15—H15A	0.9700
C1—C6	1.423 (3)	C15—H15B	0.9700
C2—C3	1.362 (3)	C16—H16A	0.9700
C2—H2	0.9300	C16—H16B	0.9700
C3—C4	1.402 (3)	C18—C19	1.510 (3)
C3—H3	0.9300	C18—H18A	0.9700
C4—C5	1.359 (3)	C18—H18B	0.9700
C4—H4	0.9300	C19—H19A	0.9700
C5—C6	1.407 (3)	C19—H19B	0.9700
C5—H5	0.9300

C17—O1—C18	109.19 (18)	C10—C11—C12	120.3 (2)
C8—N1—C1	114.03 (19)	C10—C11—H11	119.8
C7—N2—C6	113.11 (18)	C12—C11—H11	119.8
C7—N3—C14	108.24 (18)	C13—C12—C11	122.0 (2)
C7—N3—C15	125.57 (18)	C13—C12—H12	119.0
C14—N3—C15	125.53 (18)	C11—C12—H12	119.0
C17—N4—C19	113.09 (19)	C12—C13—C14	117.7 (2)
C17—N4—C16	123.23 (19)	C12—C13—H13	121.1
C19—N4—C16	123.19 (18)	C14—C13—H13	121.1
N1—C1—C2	118.8 (2)	C13—C14—N3	128.8 (2)
N1—C1—C6	122.26 (19)	C13—C14—C9	121.2 (2)
C2—C1—C6	118.94 (19)	N3—C14—C9	109.98 (19)
C3—C2—C1	120.5 (2)	N3—C15—C16	112.74 (18)
C3—C2—H2	119.7	N3—C15—H15A	109.0
C1—C2—H2	119.7	C16—C15—H15A	109.0
C2—C3—C4	120.5 (2)	N3—C15—H15B	109.0
C2—C3—H3	119.7	C16—C15—H15B	109.0
C4—C3—H3	119.7	H15A—C15—H15B	107.8
C5—C4—C3	120.4 (2)	N4—C16—C15	112.19 (17)
C5—C4—H4	119.8	N4—C16—H16A	109.2
C3—C4—H4	119.8	C15—C16—H16A	109.2
C4—C5—C6	120.6 (2)	N4—C16—H16B	109.2
C4—C5—H5	119.7	C15—C16—H16B	109.2
C6—C5—H5	119.7	H16A—C16—H16B	107.9
N2—C6—C5	118.5 (2)	O2—C17—N4	128.5 (2)
N2—C6—C1	122.53 (18)	O2—C17—O1	121.9 (2)
C5—C6—C1	118.95 (19)	N4—C17—O1	109.6 (2)
N2—C7—N3	126.0 (2)	O1—C18—C19	106.30 (19)
N2—C7—C8	124.87 (19)	O1—C18—H18A	110.5
N3—C7—C8	109.16 (18)	C19—C18—H18A	110.5
N1—C8—C7	123.16 (19)	O1—C18—H18B	110.5
N1—C8—C9	130.8 (2)	C19—C18—H18B	110.5
C7—C8—C9	106.00 (18)	H18A—C18—H18B	108.7
C10—C9—C14	119.3 (2)	N4—C19—C18	101.7 (2)
C10—C9—C8	134.1 (2)	N4—C19—H19A	111.4
C14—C9—C8	106.60 (18)	C18—C19—H19A	111.4
C11—C10—C9	119.4 (2)	N4—C19—H19B	111.4
C11—C10—H10	120.3	C18—C19—H19B	111.4
C9—C10—H10	120.3	H19A—C19—H19B	109.3

C8—N1—C1—C2	178.18 (19)	C14—C9—C10—C11	1.3 (3)
C8—N1—C1—C6	−0.5 (3)	C8—C9—C10—C11	−179.5 (2)
N1—C1—C2—C3	−178.2 (2)	C9—C10—C11—C12	0.0 (4)
C6—C1—C2—C3	0.6 (3)	C10—C11—C12—C13	−1.0 (4)
C1—C2—C3—C4	−0.3 (3)	C11—C12—C13—C14	0.6 (4)
C2—C3—C4—C5	−0.2 (4)	C12—C13—C14—N3	−178.6 (2)
C3—C4—C5—C6	0.6 (3)	C12—C13—C14—C9	0.9 (3)
C7—N2—C6—C5	−177.54 (18)	C7—N3—C14—C13	−179.2 (2)
C7—N2—C6—C1	2.3 (3)	C15—N3—C14—C13	−8.2 (4)
C4—C5—C6—N2	179.5 (2)	C7—N3—C14—C9	1.2 (2)
C4—C5—C6—C1	−0.4 (3)	C15—N3—C14—C9	172.27 (19)
N1—C1—C6—N2	−1.3 (3)	C10—C9—C14—C13	−1.8 (3)
C2—C1—C6—N2	179.99 (19)	C8—C9—C14—C13	178.8 (2)
N1—C1—C6—C5	178.46 (19)	C10—C9—C14—N3	177.76 (19)
C2—C1—C6—C5	−0.2 (3)	C8—C9—C14—N3	−1.6 (2)
C6—N2—C7—N3	178.79 (19)	C7—N3—C15—C16	87.4 (3)
C6—N2—C7—C8	−1.6 (3)	C14—N3—C15—C16	−82.2 (2)
C14—N3—C7—N2	179.42 (19)	C17—N4—C16—C15	98.1 (2)
C15—N3—C7—N2	8.3 (3)	C19—N4—C16—C15	−73.2 (3)
C14—N3—C7—C8	−0.3 (2)	N3—C15—C16—N4	−65.6 (2)
C15—N3—C7—C8	−171.34 (18)	C19—N4—C17—O2	176.5 (3)
C1—N1—C8—C7	1.2 (3)	C16—N4—C17—O2	4.4 (4)
C1—N1—C8—C9	−178.5 (2)	C19—N4—C17—O1	−4.0 (3)
N2—C7—C8—N1	−0.2 (3)	C16—N4—C17—O1	−176.09 (18)
N3—C7—C8—N1	179.50 (19)	C18—O1—C17—O2	−178.2 (2)
N2—C7—C8—C9	179.6 (2)	C18—O1—C17—N4	2.2 (3)
N3—C7—C8—C9	−0.7 (2)	C17—O1—C18—C19	0.2 (3)
N1—C8—C9—C10	1.9 (4)	C17—N4—C19—C18	3.8 (3)
C7—C8—C9—C10	−177.9 (2)	C16—N4—C19—C18	175.9 (2)
N1—C8—C9—C14	−178.8 (2)	O1—C18—C19—N4	−2.3 (3)
C7—C8—C9—C14	1.4 (2)

Experimental details

Crystal data
Chemical formula	C₁₉H₁₆N₄O₂
M_r	332.36
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	14.5565 (4), 5.8993 (2), 18.6434 (6)
β (°)	92.393 (2)
V (Å³)	1599.57 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.37 × 0.18 × 0.17

Data collection
Diffractometer	Bruker X8 APEXII
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	19296, 3216, 1897
R_int	0.054
(sin θ/λ)_max (Å⁻¹)	0.623

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.152, 0.95
No. of reflections	3216
No. of parameters	226
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.15

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Acknowledgements

We thank Université Mohammed V-Agdal and the University of Malaya for supporting this study.

References

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