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5′-Chloro­spiro­[1,3-dioxolane-2,3′-indolin]-2′-one: a potential anti­convulsant

aDepartment of Physics, Khalisani College, Chandannagar, Hooghly 712 138, India
*Correspondence e-mail: amitde03@yahoo.com

(Received 17 November 2007; accepted 30 January 2008; online 6 February 2008)

The title compound, C10H8ClNO3, is a significant anti­convulsant agent. The indolinone system is essentially planar, the dihedral angle between the rings being 2.24 (8)°. The dioxolane ring adopts an envelope conformation; the dihedral angle between the plane through its four coplanar atoms and the indolinone system is 89.8 (1)°. The crystal structure is stabilized by a three-dimensional network of inter­molecular N—H⋯O hydrogen bonds.

Related literature

For related literature, see: Codding et al. (1984[Codding, P. W., Lee, T. A. & Richardson, J. F. (1984). J. Med. Chem. 27, 649-654.]); De (1990[De, A. (1990). Acta Cryst. C46, 1891-1893.], 1992[De, A. (1992). Acta Cryst. C48, 660-662.]); De & Kitagawa (1991a[De, A. & Kitagawa, Y. (1991a). Acta Cryst. C47, 2179-2181.],b[De, A. & Kitagawa, Y. (1991b). Acta Cryst. C47, 2384-2386.]); De & Kusunoki (1991[De, A. & Kusunoki, M. (1991). J. Crystallogr. Spectrosc. Res. 21, 57-60.]); Dickerson & Geis (1969[Dickerson, R. E. & Geis, I. (1969). The Structure and Function of Proteins. Menlo Park, California: Benjamin.]); Itai et al. (1978[Itai, A., Iitaka, Y. & Kubo, A. (1978). Acta Cryst. B34, 3775-3777.]); James & Williams (1972[James, M. N. G. & Williams, G. J. B. (1972). Can. J. Chem. 50, 2407-2412.]); Popp (1977[Popp, F. D. (1977). In Anticonvulsants, edited by J. A. Vida. New York: Academic Press.], 1984[Popp, F. D. (1984). J. Heterocycl. Chem. 21, 1641-1643.]); Rajopadhye & Popp (1988[Rajopadhye, M. & Popp, F. D. (1988). J. Med. Chem. 31, 1001-1005.]); Chakraborty & Talapatra (1985[Chakraborty, D. K. & Talapatra, S. K. (1985). Acta Cryst. C41, 1365-1366.]); Chakraborty et al. (1985[Chakraborty, D. K., Talapatra, S. K. & Chatterjee, A. (1985). Acta Cryst. C41, 1363-1364.]).

[Scheme 1]

Experimental

Crystal data
  • C10H8ClNO3

  • Mr = 225.62

  • Monoclinic, I 2/c

  • a = 18.266 (2) Å

  • b = 7.360 (1) Å

  • c = 14.821 (1) Å

  • β = 92.855 (7)°

  • V = 1990.0 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.37 mm−1

  • T = 298 (2) K

  • 0.50 × 0.30 × 0.30 mm

Data collection
  • Rigaku AFC-4 diffractometer

  • Absorption correction: none

  • 2479 measured reflections

  • 2297 independent reflections

  • 1591 reflections with I > 2σ(I)

  • Rint = 0.042

  • 3 standard reflections every 100 reflections intensity decay: 0.2%

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.189

  • S = 0.83

  • 2297 reflections

  • 160 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.52 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.82 (3) 2.11 (3) 2.885 (4) 157.4 (3)
Symmetry code: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z].

Data collection: AFC-4 Diffractometer Control Software (Rigaku, 1997[Rigaku (1997). AFC-4 Diffractometer Control Software. Rigaku Corporation, Tokyo, Japan.]); cell refinement: AFC-4 Diffractometer Control Software; data reduction: AFC-4 Diffractometer Control Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP (Johnson, 1965[Johnson, C. K. (1965). ORTEP. Report ORNL-3794. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1983[Nardelli, M. (1983). Comput. Chem. 7, 95-97.]).

Supporting information


Comment top

Anti-epileptic drugs have diverse chemical structures and complex physiological and pharmacological actions. The search for potential drugs and their mechanism of action has been difficult because of their complexity. A series of spiro(1,3-dioxane-2,3'-indolin)-2'-one and structural analogues active against electrically and chemically induced seizures have been studied. These compounds contain both an oxoindole and a dioxolane moiety which have independently been seen in other anticonvulsants (Popp, 1977, 1984). The basic model compound, mentioned above, was used to study the effects of various electron-donating, electron withdrawing and hydrophobic groups on the activity of the molecule. A bulky hydrophobic substituent at the 1'-position (oxoindole) generally tends to decrease the activity. The present compound, a chloro analogue was found to be most potent in the MES test. Since no common target site has yet been established, X-ray analysis was undertaken to search structural information which may help in the understanding of the mechanism of action at the molecular level.

The conformation of the title compound along with the atom-numbering scheme is shown in Fig 1. The carbonyl C atom to tetrahedral C atom distance is typical of a single bond. The C(2) - C(3) bond distance is slightly shorter but closely similar to the values found in other indoline nuclie (Itai et al., 1978; Chakraborty & Talapatra, 1985; Chakraborty et al., 1985; De & Kitagawa, 1991a,b; De, 1992). The lone pair of electrons on N(1) is involved in conjugation with the carbonyl group. This is also indicated by the slight lengthening of the C=O double bond [1.220 (4) Å] and the concomitant shortening of the two N - C(sp2) single bonds [1.341 (4) Å and 1.412 (4) Å] (Codding et al., 1984). The least-squares planes through the five- and six-membered rings are inclined to one another at 2.24 (8)° and each of them are almost planar. The plane containing the atoms C(2), O(2), O(3), C(9) and C(10) is inclined to the overall plane through the indolinone group by 89.8 (1)°. The C—NH—CO—C grouping resembles a cis peptide bond. Six atoms of this group [C(8), N(1), H1,C(1),O(1),C(2)] are almost planar. The OC—N bond distance [1.341 (4) Å] is not as short as the normal peptide bond(1.325 Å) (Dickerson & Geis,1969). The packing of the molecule is shown in Fig. 2. The amide nitrogen, N(1), forms a hydrogen bond with the carbonyl oxygen O(1) [N(1) - H1] = 0.82 (3), N(1)···O(1) = 2.885 (4), H1···O(1) = 2.11 (3) Å, N(1) –H1···O(1) = 157.4 (3) °]. The molecules are thus held together by a three-dimensional network of hydrogen bonds.

Related literature top

For related literature, see: Codding et al. (1984); De (1990, 1992); De & Kitagawa (1991a,b); De & Kusunoki (1991); Dickerson & Geis (1969); Itai et al. (1978); James & Williams (1972); Popp (1977, 1984); Rajopadhye & Popp (1988); Chakraborty & Talapatra (1985); Chakraborty et al. (1985).

Experimental top

The synthesis of the compound has been described earlier (Rajopadhye & Popp, 1988). Diffraction quality crystals were obtained by slow evaporation of an ethanol solution at room temperature.

Refinement top

All the hydrogen atoms in the structure were located in a difference map except the two H-atoms on C10. They were placed at geometrically idealized positions. Geometric calculations were performed using SHELXL-97, PARST (Nardelli, 1983) programs.

Computing details top

Data collection: AFC-4 Diffractometer Control Software (Rigaku, 1997); cell refinement: AFC-4 Diffractometer Control Software (Rigaku, 1997); data reduction: AFC-4 Diffractometer Control Software (Rigaku, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP (Johnson, 1965); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PARST (Nardelli, 1983).

Figures top
[Figure 1] Fig. 1. ORTEP (Johnson, 1965) diagram of the Molecular structure with atom labels showing displacement ellipsoids at 50% probablity.
[Figure 2] Fig. 2. Packing of the molecule viewed down the b axis.
5'-Chlorospiro[1,3-dioxolane-2,3'-indolin]-2'-one top
Crystal data top
C10H8ClNO3F(000) = 928
Mr = 225.62Dx = 1.506 Mg m3
Dm = 1.498 Mg m3
Dm measured by flotation
Monoclinic, I2/cMelting point: 460 K
Hall symbol: -I 2ycMo Kα radiation, λ = 0.71073 Å
a = 18.266 (2) ÅCell parameters from 25 reflections
b = 7.360 (1) Åθ = 2.2–27.5°
c = 14.821 (1) ŵ = 0.37 mm1
β = 92.855 (7)°T = 298 K
V = 1990.0 (4) Å3Needle, colourless
Z = 80.50 × 0.30 × 0.30 mm
Data collection top
Rigaku AFC-4
diffractometer
Rint = 0.042
Radiation source: fine-focus sealed tubeθmax = 27.5°, θmin = 2.2°
Graphite monochromatorh = 2323
ω scansk = 09
2479 measured reflectionsl = 019
2297 independent reflections3 standard reflections every 100 reflections
1591 reflections with I > 2σ(I) intensity decay: 0.2%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.189H atoms treated by a mixture of independent and constrained refinement
S = 0.83 w = 1/[σ2(Fo2) + (0.1365P)2 + 2.6179P]
where P = (Fo2 + 2Fc2)/3
2297 reflections(Δ/σ)max = 0.006
160 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.52 e Å3
Crystal data top
C10H8ClNO3V = 1990.0 (4) Å3
Mr = 225.62Z = 8
Monoclinic, I2/cMo Kα radiation
a = 18.266 (2) ŵ = 0.37 mm1
b = 7.360 (1) ÅT = 298 K
c = 14.821 (1) Å0.50 × 0.30 × 0.30 mm
β = 92.855 (7)°
Data collection top
Rigaku AFC-4
diffractometer
Rint = 0.042
2479 measured reflections3 standard reflections every 100 reflections
2297 independent reflections intensity decay: 0.2%
1591 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.189H atoms treated by a mixture of independent and constrained refinement
S = 0.83Δρmax = 0.34 e Å3
2297 reflectionsΔρmin = 0.52 e Å3
160 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 on F2 for ALL reflections except for 0 with very negative F2 or flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating _R_factor_obs 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
xyzUiso*/Ueq
Cl10.40898 (6)0.00775 (11)0.43060 (5)0.0825 (4)
O10.3184 (2)0.5049 (4)0.0001 (2)0.0931 (9)
O20.37608 (10)0.5934 (2)0.18885 (12)0.0534 (5)
O30.45532 (9)0.4244 (2)0.11210 (12)0.0494 (4)
N10.28723 (12)0.2542 (4)0.0815 (2)0.0612 (6)
C10.3263 (2)0.4038 (4)0.0651 (2)0.0596 (7)
C20.38452 (12)0.4261 (3)0.1450 (2)0.0442 (5)
C30.36853 (11)0.2671 (3)0.20354 (15)0.0418 (5)
C40.40017 (12)0.2147 (3)0.2858 (2)0.0446 (5)
C50.3712 (2)0.0628 (3)0.3264 (2)0.0516 (6)
C60.3125 (2)0.0317 (4)0.2873 (2)0.0634 (8)
C70.2809 (2)0.0217 (4)0.2041 (2)0.0606 (7)
C80.31030 (12)0.1704 (3)0.1639 (2)0.0484 (5)
C90.4219 (2)0.7216 (4)0.1450 (2)0.0678 (8)
C100.4787 (2)0.6085 (4)0.1035 (3)0.0759 (9)
H40.4389 (16)0.275 (4)0.3142 (18)0.051 (7)*
H60.2955 (19)0.126 (5)0.316 (2)0.069 (9)*
H70.234 (2)0.037 (5)0.181 (2)0.077 (10)*
H10.2565 (18)0.206 (5)0.047 (2)0.062 (9)*
H910.393 (2)0.792 (6)0.102 (3)0.110 (14)*
H920.441 (2)0.808 (7)0.189 (3)0.086 (11)*
H1010.52600.62630.13510.08*
H1020.48220.64010.04030.08*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1293 (9)0.0619 (5)0.0567 (5)0.0119 (4)0.0092 (5)0.0165 (3)
O10.099 (2)0.100 (2)0.077 (2)0.0173 (14)0.0313 (13)0.0273 (14)
O20.0595 (10)0.0389 (9)0.0630 (10)0.0018 (7)0.0167 (8)0.0016 (7)
O30.0459 (8)0.0434 (9)0.0594 (10)0.0071 (7)0.0089 (7)0.0065 (7)
N10.0475 (11)0.0723 (15)0.0617 (13)0.0053 (11)0.0181 (10)0.0182 (12)
C10.0552 (13)0.065 (2)0.0573 (14)0.0149 (12)0.0140 (11)0.0000 (12)
C20.0427 (10)0.0426 (11)0.0467 (11)0.0043 (8)0.0024 (8)0.0014 (9)
C30.0367 (9)0.0384 (10)0.0500 (11)0.0013 (8)0.0004 (8)0.0026 (9)
C40.0426 (11)0.0400 (11)0.0509 (12)0.0019 (9)0.0016 (9)0.0015 (9)
C50.0677 (14)0.0371 (11)0.0514 (12)0.0043 (10)0.0157 (11)0.0016 (9)
C60.077 (2)0.0349 (11)0.081 (2)0.0119 (12)0.031 (2)0.0082 (12)
C70.0508 (13)0.0505 (14)0.081 (2)0.0119 (11)0.0094 (12)0.0206 (13)
C80.0393 (10)0.0447 (11)0.0608 (13)0.0020 (9)0.0001 (9)0.0156 (10)
C90.083 (2)0.0459 (14)0.076 (2)0.0025 (13)0.022 (2)0.0066 (14)
C100.086 (2)0.051 (2)0.095 (2)0.0020 (15)0.041 (2)0.005 (2)
Geometric parameters (Å, º) top
Cl1—C51.740 (3)C4—C51.386 (3)
O1—C11.220 (4)C4—H40.92 (3)
O2—C21.404 (3)C5—C61.381 (4)
O2—C91.438 (3)C6—C71.392 (5)
O3—C21.405 (3)C6—H60.88 (4)
O3—C101.429 (4)C7—C81.369 (4)
N1—C11.341 (4)C7—H71.01 (4)
N1—C81.412 (4)C9—C101.487 (4)
N1—H10.82 (3)C9—H910.96 (4)
C1—C21.560 (3)C9—H920.96 (4)
C2—C31.494 (3)C10—H1010.97
C3—C41.378 (3)C10—H1020.97
C3—C81.386 (3)
C2—O2—C9106.6 (2)C4—C5—Cl1118.8 (2)
C2—O3—C10107.9 (2)C5—C6—C7120.6 (2)
C1—N1—C8112.1 (2)C5—C6—H6119 (2)
C1—N1—H1127 (2)C7—C6—H6121 (2)
C8—N1—H1121 (2)C8—C7—C6117.2 (2)
O1—C1—N1127.0 (3)C8—C7—H7123 (2)
O1—C1—C2125.8 (3)C6—C7—H7119 (2)
N1—C1—C2107.3 (2)C7—C8—C3122.4 (2)
O3—C2—O2107.0 (2)C7—C8—N1128.2 (2)
O3—C2—C3113.9 (2)C3—C8—N1109.4 (2)
O2—C2—C3112.9 (2)O2—C9—C10104.7 (2)
O3—C2—C1109.8 (2)O2—C9—H91110 (3)
O2—C2—C1110.9 (2)C10—C9—H91114 (3)
C3—C2—C1102.3 (2)O2—C9—H92109 (2)
C4—C3—C8120.7 (2)C10—C9—H92115 (2)
C4—C3—C2130.3 (2)H91—C9—H92105 (4)
C8—C3—C2108.9 (2)O3—C10—C9106.0 (2)
C3—C4—C5117.2 (2)O3—C10—H101110.3
C3—C4—H4123.2 (17)C9—C10—H101111.0
C5—C4—H4119.6 (17)O3—C10—H102110.3
C6—C5—C4122.0 (3)C9—C10—H102110.3
C6—C5—Cl1119.2 (2)H101—C10—H102110.0
C9—O2—C2—O328.9 (2)O2—C2—C3—C8118.8 (2)
C9—O2—C2—C190.9 (2)O3—C2—C3—C463.6 (3)
C9—O2—C2—C3155.0 (2)O3—C2—C3—C8118.9 (2)
C2—O2—C9—C1023.5 (3)C1—C2—C3—C4177.9 (2)
C10—O3—C2—O222.6 (3)C1—C2—C3—C80.4 (2)
C10—O3—C2—C197.9 (2)C2—C3—C4—C5177.2 (2)
C10—O3—C2—C3148.1 (2)C2—C3—C8—N10.9 (3)
C2—O3—C10—C97.5 (3)C2—C3—C8—C7176.9 (2)
C8—N1—C1—O1179.1 (3)C4—C3—C8—N1178.7 (2)
C8—N1—C1—C20.8 (3)C4—C3—C8—C70.9 (4)
C1—N1—C8—C31.1 (3)C3—C4—C5—Cl1179.6 (2)
C1—N1—C8—C7176.6 (3)C3—C4—C5—C60.9 (4)
O1—C1—C2—O259.0 (4)Cl1—C5—C6—C7179.8 (2)
O1—C1—C2—O359.1 (4)C4—C5—C6—C71.0 (4)
O1—C1—C2—C3179.7 (3)C5—C6—C7—C80.2 (4)
N1—C1—C2—O2120.9 (2)C6—C7—C8—N1178.1 (3)
N1—C1—C2—O3121.0 (2)C6—C7—C8—C30.7 (4)
N1—C1—C2—C30.2 (3)O2—C9—C10—O39.7 (3)
O2—C2—C3—C458.7 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.82 (3)2.11 (3)2.885 (4)157.4 (3)
Symmetry code: (i) x+1/2, y1/2, z.

Experimental details

Crystal data
Chemical formulaC10H8ClNO3
Mr225.62
Crystal system, space groupMonoclinic, I2/c
Temperature (K)298
a, b, c (Å)18.266 (2), 7.360 (1), 14.821 (1)
β (°) 92.855 (7)
V3)1990.0 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.37
Crystal size (mm)0.50 × 0.30 × 0.30
Data collection
DiffractometerRigaku AFC-4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
2479, 2297, 1591
Rint0.042
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.189, 0.83
No. of reflections2297
No. of parameters160
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.34, 0.52

Computer programs: AFC-4 Diffractometer Control Software (Rigaku, 1997), SHELXS97 (Sheldrick, 2008), ORTEP (Johnson, 1965), SHELXL97 (Sheldrick, 2008) and PARST (Nardelli, 1983).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.82 (3)2.11 (3)2.885 (4)157.4 (3)
Symmetry code: (i) x+1/2, y1/2, z.
 

Acknowledgements

The author thanks Dr Frank D. Popp of the University of Missouri–Kansas City, for the gift of the sample used in this investigation, and the University Grants Commission, India, for financial support.

References

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