supplementary materials


zq2211 scheme

Acta Cryst. (2013). E69, o1849-o1850    [ doi:10.1107/S1600536813031279 ]

(3aR,8bR)-3a,8b-Dihy­droxy-1-(4-meth­oxy­phen­yl)-2-methyl­sulfan­yl-3-nitro-1,8b-di­hydro­indeno­[1,2-b]pyrrol-4(3aH)-one

R. A. Nagalakshmi, J. Suresh, V. Jeyachandran, R. R. Kumar and P. L. N. Lakshman

Abstract top

In the title compound, C19H16N2O6S, the pyrrolidine ring adopts a twisted conformation with puckering parameters q2 = 0.088 (3) Å and [Phi]2 = 61.5 (14)°. The cyclo­pentane ring adopts a twisted conformation with puckering parameters q2 = 0.099 (2) Å and [Phi]2 = 242.8 (14)°. A weak intra­molecular O-H...O inter­action occurs. In the crystal, pairs of C-H...O inter­actions generate dimers with graph-set motif R22(24) and they are interconnected by pairs of O-H...O hydrogen bonds, which link the mol­ecules into inversion dimers with graph-set motif R22(10).

Comment top

Pyrrolidine ring system is a frequently encountered structural motif in many biologically relevant alkaloids (Cordell, 1981). Pyrrolidine derivatives possess anticonvulsant (Obniska et al., 2010), anti-angiogenic (Morais et al., 2009) and antitumor activities (Bello et al., 2010). In view of the high medicinal value of these compounds in conjunction with our research interests, prompted us to synthesize and report the X-ray studies of the title compound (Fig. 1).

In the title compound, C19H16N2O6S, the pyrrolidine ring (N1/C1/C2/C3/C4) adopts a twisted conformation with the puckering parameters q2 = 0.088 (3) Å and Φ2 = 61.5 (14) °. The cyclopentane ring (C1/C2/C6–C8) adopts a twisted conformation with the puckering parameters q2 = 0.099 (2) Å and Φ2 = 242.8 (14) °. The benzene ring of the indane ring is planar with a r.m.s deviation of 0.0113 (1) °. The methoxy benzene ring (C13–C18) is planar with a r.m.s. deviation of 0.0120 Å. The sum of the C—N—C bond angles around N1 atom (352.99 (18)°) is implying a noticeable flattening of the trigonal pyramidal geometry about N1. The conformation of the methylsulfanyl moiety is antiperiplanar, as evidenced from the torsion angles C5—S1—C4—C3 = 165.1 (2) °. The bond length C4—S1 = 1.727 (2) Å is shorter than S1—C5 = 1.804 (3) Å as found in a similar structure (Ghorbani, 2012). The methyl group of the methyl sulfanyl substituent is tilted towards the plane of the benzene ring as indicated by the angle C4—S1—C5 = 106.52 (11) °. Due to the p - π conjugation of atom O6, the bond distance of O6—C16 (1.371 (2) Å) is significantly shorter than the bond distance of O6—C19 (1.427 (3) Å) as found in a similar structure (Liu et al., 2008). The dihedral angle 68.8 (1) ° between the mean planes of the phenyl ring and of the pyrrolidine ring (C1/C3/C4/N1) indicates that the substituent at N1 is in an equatorial position. The shorter bond lengths, C4—N1 (1.352 (3) Å), C3—N2 (1.385 (3) Å) than the normal C—N (1.47 Å) indicate the electron donating effects of nitrogen atoms.

The crystal structure features a weak intramolecular O—H···O interaction and some intermolecular C—H···O and O—H···O interactions. The O3—H3···O1i (symmetry code: i = -x+2, -y, -z+1) intermolecular interaction connects, inversely related dimers generating a graph set motif R22(10) (Cremer & Pople, 1975). The C11—H11···O6 intermolecular interaction connects dimers generating a graph set motif R22(24) (Fig 2).

Related literature top

For the importance of pyrrolidine derivatives, see: Cordell (1981); Morais et al. (2009); Bello et al. (2010); Obniska et al. (2010). For related structures, see: Liu et al. (2008); Ghorbani (2012). For additional conformation analysis, see: Cremer & Pople (1975).

Experimental top

A mixture of (E)-4-methoxy-N-(1-(methylthio)-2-nitrovinyl)aniline (1 mmol) with ninhydrin (1 mmol) in presence of glacial AcOH (3–5 drops) was thoroughly ground in a pestle and mortar at room temperature for 2–10 min. The reaction progress was monitored by thin layer chromatography. After completion of the reaction, the reaction mixture was triturated with crushed ice, the resulting solid filtered off and washed with water to afford the pure product. The compound was further recrystallized from ethanol to obtain suitable crystals for X-ray analysis. Melting point 473 K - 475 K. Yield: 95%

Refinement top

H atoms were placed at calculated positions and allowed to ride on their carrier atoms with C—H = 0.93–0.98 Å and O—H = 0.82 Å. Uiso = 1.2Ueq(C) for CH2 and CH groups and Uiso = 1.5Ueq(C) for CH3 and OH groups.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 20% probability displacement ellipsoids and the atom-numbering scheme. H-atoms are omitted for clarity.
[Figure 2] Fig. 2. The partial packing diagram showing O—H···O and C—H···O interactions.
(3aR,8bR)-3a,8b-Dihydroxy-1-(4-methoxyphenyl)-2-methylsulfanyl-3-nitro-1,8b-dihydroindeno[1,2-b]pyrrol-4(3aH)-one top
Crystal data top
C19H16N2O6SF(000) = 832
Mr = 400.40Dx = 1.503 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -p 2ynCell parameters from 2000 reflections
a = 13.6601 (7) Åθ = 2–31°
b = 8.5782 (5) ŵ = 0.23 mm1
c = 15.2373 (8) ÅT = 293 K
β = 97.684 (3)°Block, yellow
V = 1769.46 (17) Å30.21 × 0.19 × 0.18 mm
Z = 4
Data collection top
Bruker Kappa APEXII
diffractometer
3311 independent reflections
Radiation source: fine-focus sealed tube2661 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
Detector resolution: 0 pixels mm-1θmax = 25.5°, θmin = 1.9°
ω and φ scansh = 1615
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 107
Tmin = 0.967, Tmax = 0.974l = 1718
13771 measured reflections
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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.155H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0989P)2 + 0.7209P]
where P = (Fo2 + 2Fc2)/3
3311 reflections(Δ/σ)max < 0.001
253 parametersΔρmax = 0.42 e Å3
0 restraintsΔρmin = 0.44 e Å3
Crystal data top
C19H16N2O6SV = 1769.46 (17) Å3
Mr = 400.40Z = 4
Monoclinic, P21/nMo Kα radiation
a = 13.6601 (7) ŵ = 0.23 mm1
b = 8.5782 (5) ÅT = 293 K
c = 15.2373 (8) Å0.21 × 0.19 × 0.18 mm
β = 97.684 (3)°
Data collection top
Bruker Kappa APEXII
diffractometer
3311 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2661 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.974Rint = 0.047
13771 measured reflectionsθmax = 25.5°
Refinement top
R[F2 > 2σ(F2)] = 0.053H-atom parameters constrained
wR(F2) = 0.155Δρmax = 0.42 e Å3
S = 1.02Δρmin = 0.44 e Å3
3311 reflectionsAbsolute structure: ?
253 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
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 F.2 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
C10.70509 (13)0.0236 (3)0.42776 (14)0.0363 (5)
C20.82032 (13)0.0315 (3)0.43000 (14)0.0375 (5)
C30.82888 (14)0.0735 (3)0.33568 (15)0.0387 (5)
C40.73865 (14)0.0682 (2)0.28246 (14)0.0361 (5)
C50.60238 (18)0.0213 (4)0.12776 (17)0.0575 (7)
H5A0.59170.02970.06440.086*
H5B0.55510.08490.15250.086*
H5C0.59480.08540.14460.086*
C60.85309 (15)0.1658 (3)0.49362 (14)0.0407 (5)
C70.76369 (15)0.2479 (3)0.51268 (14)0.0410 (5)
C80.67980 (14)0.1644 (3)0.48003 (13)0.0389 (5)
C90.58736 (16)0.2127 (3)0.49893 (14)0.0468 (6)
H90.53070.15550.47970.056*
C100.58276 (19)0.3479 (3)0.54700 (16)0.0557 (7)
H100.52180.38260.55990.067*
C110.6668 (2)0.4338 (3)0.57670 (18)0.0609 (7)
H110.66110.52600.60770.073*
C120.75837 (19)0.3837 (3)0.56070 (16)0.0540 (6)
H120.81510.43950.58160.065*
C130.56455 (13)0.0879 (2)0.31000 (13)0.0337 (5)
C140.54498 (14)0.2415 (3)0.28747 (14)0.0393 (5)
H140.59670.30940.28130.047*
C150.44902 (14)0.2942 (3)0.27415 (15)0.0413 (5)
H150.43550.39660.25650.050*
C160.37246 (13)0.1939 (3)0.28725 (14)0.0367 (5)
C170.39162 (14)0.0406 (3)0.30889 (15)0.0400 (5)
H170.34000.02680.31640.048*
C180.48858 (14)0.0138 (3)0.31960 (14)0.0377 (5)
H180.50200.11800.33310.045*
C190.20231 (15)0.1754 (3)0.30760 (19)0.0563 (7)
H19A0.14210.23400.29630.085*
H19B0.21810.15790.37010.085*
H19C0.19420.07710.27740.085*
N10.66559 (11)0.0372 (2)0.33164 (11)0.0349 (4)
N20.91927 (13)0.0968 (2)0.30602 (14)0.0452 (5)
O10.93701 (11)0.1960 (2)0.52411 (12)0.0554 (5)
O20.67032 (10)0.11114 (19)0.46335 (10)0.0443 (4)
H20.68440.18680.43460.066*
O30.86160 (10)0.11224 (19)0.45807 (11)0.0475 (4)
H30.92080.11190.45370.071*
O40.92122 (12)0.1327 (2)0.22720 (13)0.0597 (5)
O50.99515 (11)0.0817 (2)0.35945 (13)0.0621 (5)
O60.28043 (9)0.2606 (2)0.27626 (11)0.0473 (4)
S10.72558 (4)0.08679 (9)0.16864 (4)0.0526 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0206 (9)0.0434 (13)0.0459 (11)0.0030 (8)0.0079 (8)0.0032 (9)
C20.0209 (9)0.0407 (12)0.0519 (12)0.0040 (8)0.0077 (8)0.0005 (9)
C30.0242 (9)0.0430 (13)0.0514 (12)0.0010 (8)0.0143 (8)0.0048 (9)
C40.0274 (9)0.0350 (11)0.0483 (11)0.0048 (8)0.0138 (8)0.0023 (9)
C50.0478 (13)0.0747 (19)0.0499 (13)0.0045 (12)0.0060 (10)0.0085 (13)
C60.0293 (10)0.0464 (13)0.0466 (11)0.0039 (9)0.0056 (8)0.0001 (10)
C70.0343 (10)0.0467 (13)0.0424 (11)0.0065 (9)0.0067 (8)0.0003 (9)
C80.0295 (10)0.0468 (13)0.0416 (10)0.0076 (8)0.0095 (8)0.0019 (9)
C90.0335 (10)0.0617 (16)0.0482 (12)0.0097 (10)0.0158 (9)0.0032 (11)
C100.0508 (14)0.0675 (18)0.0533 (13)0.0196 (12)0.0235 (11)0.0003 (12)
C110.0675 (17)0.0617 (18)0.0571 (15)0.0136 (13)0.0216 (13)0.0126 (13)
C120.0523 (14)0.0603 (17)0.0505 (13)0.0019 (11)0.0104 (11)0.0109 (12)
C130.0189 (9)0.0404 (12)0.0426 (11)0.0019 (7)0.0074 (7)0.0010 (8)
C140.0219 (9)0.0413 (13)0.0568 (12)0.0010 (8)0.0136 (8)0.0046 (10)
C150.0272 (10)0.0400 (13)0.0583 (13)0.0042 (8)0.0118 (9)0.0090 (10)
C160.0200 (9)0.0449 (13)0.0457 (11)0.0024 (8)0.0068 (7)0.0011 (9)
C170.0218 (9)0.0444 (13)0.0547 (12)0.0044 (8)0.0086 (8)0.0008 (10)
C180.0273 (9)0.0364 (12)0.0504 (12)0.0003 (8)0.0085 (8)0.0018 (9)
C190.0245 (10)0.0686 (17)0.0778 (17)0.0003 (10)0.0140 (10)0.0083 (14)
N10.0186 (7)0.0440 (11)0.0436 (9)0.0031 (6)0.0094 (6)0.0022 (8)
N20.0292 (9)0.0450 (12)0.0653 (13)0.0016 (7)0.0203 (8)0.0069 (9)
O10.0299 (8)0.0645 (12)0.0697 (11)0.0010 (7)0.0008 (7)0.0141 (9)
O20.0334 (8)0.0465 (10)0.0547 (9)0.0002 (6)0.0126 (6)0.0093 (7)
O30.0247 (7)0.0448 (10)0.0719 (11)0.0070 (6)0.0022 (7)0.0016 (8)
O40.0439 (9)0.0645 (12)0.0767 (12)0.0021 (8)0.0300 (8)0.0084 (10)
O50.0217 (8)0.0881 (14)0.0779 (12)0.0032 (7)0.0118 (8)0.0144 (10)
O60.0194 (6)0.0518 (10)0.0723 (10)0.0048 (6)0.0117 (6)0.0072 (8)
S10.0402 (3)0.0725 (5)0.0474 (4)0.0029 (3)0.0146 (3)0.0101 (3)
Geometric parameters (Å, º) top
C1—O21.387 (3)C11—C121.375 (4)
C1—N11.496 (3)C11—H110.9300
C1—C81.512 (3)C12—H120.9300
C1—C21.571 (2)C13—C141.378 (3)
C2—O31.399 (3)C13—C181.379 (3)
C2—C31.501 (3)C13—N11.443 (2)
C2—C61.533 (3)C14—C151.376 (3)
C3—C41.383 (3)C14—H140.9300
C3—N21.385 (3)C15—C161.389 (3)
C4—N11.352 (3)C15—H150.9300
C4—S11.727 (2)C16—O61.371 (2)
C5—S11.804 (3)C16—C171.372 (3)
C5—H5A0.9600C17—C181.393 (3)
C5—H5B0.9600C17—H170.9300
C5—H5C0.9600C18—H180.9300
C6—O11.206 (3)C19—O61.427 (3)
C6—C71.472 (3)C19—H19A0.9600
C7—C121.383 (3)C19—H19B0.9600
C7—C81.386 (3)C19—H19C0.9600
C8—C91.395 (3)N2—O51.236 (3)
C9—C101.378 (4)N2—O41.244 (3)
C9—H90.9300O2—H20.8200
C10—C111.388 (4)O3—H30.8200
C10—H100.9300
O2—C1—N1110.51 (17)C12—C11—H11119.7
O2—C1—C8110.19 (16)C10—C11—H11119.7
N1—C1—C8112.04 (17)C11—C12—C7118.1 (2)
O2—C1—C2114.95 (16)C11—C12—H12121.0
N1—C1—C2104.30 (15)C7—C12—H12121.0
C8—C1—C2104.65 (16)C14—C13—C18120.52 (18)
O3—C2—C3115.10 (17)C14—C13—N1119.52 (17)
O3—C2—C6113.41 (17)C18—C13—N1119.71 (19)
C3—C2—C6111.82 (18)C15—C14—C13120.01 (19)
O3—C2—C1109.29 (17)C15—C14—H14120.0
C3—C2—C1101.28 (15)C13—C14—H14120.0
C6—C2—C1104.66 (16)C14—C15—C16119.7 (2)
C4—C3—N2125.2 (2)C14—C15—H15120.1
C4—C3—C2112.11 (17)C16—C15—H15120.1
N2—C3—C2122.27 (18)O6—C16—C17124.89 (18)
N1—C4—C3110.34 (18)O6—C16—C15114.77 (19)
N1—C4—S1126.15 (16)C17—C16—C15120.34 (18)
C3—C4—S1123.39 (15)C16—C17—C18119.81 (19)
S1—C5—H5A109.5C16—C17—H17120.1
S1—C5—H5B109.5C18—C17—H17120.1
H5A—C5—H5B109.5C13—C18—C17119.5 (2)
S1—C5—H5C109.5C13—C18—H18120.2
H5A—C5—H5C109.5C17—C18—H18120.2
H5B—C5—H5C109.5O6—C19—H19A109.5
O1—C6—C7126.3 (2)O6—C19—H19B109.5
O1—C6—C2125.94 (19)H19A—C19—H19B109.5
C7—C6—C2107.72 (17)O6—C19—H19C109.5
C12—C7—C8121.7 (2)H19A—C19—H19C109.5
C12—C7—C6127.7 (2)H19B—C19—H19C109.5
C8—C7—C6110.5 (2)C4—N1—C13124.66 (17)
C7—C8—C9120.0 (2)C4—N1—C1111.19 (15)
C7—C8—C1111.45 (17)C13—N1—C1117.14 (15)
C9—C8—C1128.5 (2)O5—N2—O4122.52 (18)
C10—C9—C8117.8 (2)O5—N2—C3118.4 (2)
C10—C9—H9121.1O4—N2—C3119.08 (19)
C8—C9—H9121.1C1—O2—H2109.5
C9—C10—C11121.7 (2)C2—O3—H3109.5
C9—C10—H10119.1C16—O6—C19117.35 (18)
C11—C10—H10119.1C4—S1—C5106.52 (11)
C12—C11—C10120.6 (3)
O2—C1—C2—O37.7 (2)C7—C8—C9—C102.8 (3)
N1—C1—C2—O3113.49 (18)C1—C8—C9—C10178.9 (2)
C8—C1—C2—O3128.67 (18)C8—C9—C10—C110.5 (4)
O2—C1—C2—C3129.54 (19)C9—C10—C11—C121.6 (4)
N1—C1—C2—C38.4 (2)C10—C11—C12—C71.4 (4)
C8—C1—C2—C3109.45 (18)C8—C7—C12—C110.9 (4)
O2—C1—C2—C6114.1 (2)C6—C7—C12—C11174.7 (2)
N1—C1—C2—C6124.73 (18)C18—C13—C14—C150.2 (3)
C8—C1—C2—C66.9 (2)N1—C13—C14—C15174.4 (2)
O3—C2—C3—C4109.7 (2)C13—C14—C15—C162.8 (3)
C6—C2—C3—C4119.03 (19)C14—C15—C16—O6177.0 (2)
C1—C2—C3—C48.1 (2)C14—C15—C16—C173.4 (3)
O3—C2—C3—N263.6 (3)O6—C16—C17—C18179.1 (2)
C6—C2—C3—N267.7 (3)C15—C16—C17—C181.4 (3)
C1—C2—C3—N2178.6 (2)C14—C13—C18—C171.9 (3)
N2—C3—C4—N1177.5 (2)N1—C13—C18—C17172.37 (19)
C2—C3—C4—N14.4 (3)C16—C17—C18—C131.3 (3)
N2—C3—C4—S11.3 (3)C3—C4—N1—C13151.4 (2)
C2—C3—C4—S1171.80 (15)S1—C4—N1—C1332.5 (3)
O3—C2—C6—O149.2 (3)C3—C4—N1—C11.8 (2)
C3—C2—C6—O182.9 (3)S1—C4—N1—C1177.84 (15)
C1—C2—C6—O1168.3 (2)C14—C13—N1—C448.6 (3)
O3—C2—C6—C7129.12 (18)C18—C13—N1—C4137.1 (2)
C3—C2—C6—C798.72 (19)C14—C13—N1—C199.4 (2)
C1—C2—C6—C710.1 (2)C18—C13—N1—C174.9 (3)
O1—C6—C7—C127.6 (4)O2—C1—N1—C4130.78 (17)
C2—C6—C7—C12174.1 (2)C8—C1—N1—C4105.92 (19)
O1—C6—C7—C8168.5 (2)C2—C1—N1—C46.7 (2)
C2—C6—C7—C89.9 (3)O2—C1—N1—C1377.1 (2)
C12—C7—C8—C93.1 (3)C8—C1—N1—C1346.2 (2)
C6—C7—C8—C9173.2 (2)C2—C1—N1—C13158.86 (17)
C12—C7—C8—C1178.3 (2)C4—C3—N2—O5172.1 (2)
C6—C7—C8—C15.3 (3)C2—C3—N2—O50.3 (3)
O2—C1—C8—C7122.85 (19)C4—C3—N2—O48.2 (3)
N1—C1—C8—C7113.67 (19)C2—C3—N2—O4179.4 (2)
C2—C1—C8—C71.3 (2)C17—C16—O6—C1914.1 (3)
O2—C1—C8—C955.6 (3)C15—C16—O6—C19166.3 (2)
N1—C1—C8—C967.9 (3)N1—C4—S1—C510.5 (2)
C2—C1—C8—C9179.7 (2)C3—C4—S1—C5165.1 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O50.822.503.014 (3)122
O3—H3···O1i0.822.062.821 (2)155
C11—H11···O6ii0.932.603.461 (3)155
Symmetry codes: (i) x+2, y, z+1; (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3···O50.822.503.014 (3)122.0
O3—H3···O1i0.822.062.821 (2)154.8
C11—H11···O6ii0.932.603.461 (3)155.1
Symmetry codes: (i) x+2, y, z+1; (ii) x+1, y+1, z+1.
Acknowledgements top

JS and RAN thank the management of the Madura College for their encouragement and support. RRK thanks the DST, New Delhi, for funds under the fast-track scheme (No. SR/FT/CS-073/2009)

references
References top

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