organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

N-[2-(3-Methyl-1-oxo-1,2-di­hydro­pyrrolo­[1,2-a]pyrazin-2-yl)eth­yl]methane­sulfonamide

aPharmaceutical Research Centre, PCSIR Labs Complex, Karachi 75280, Pakistan, bDepartment of Pharmaceutical Engineering, Biotechnology College, Tianjin University of Science & Technology (TUST), Tianjin 300457, People's Republic of China, and cCrystal Materials Research Unit, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
*Correspondence e-mail: salmankhann@hotmail.com

(Received 30 June 2010; accepted 2 July 2010; online 10 July 2010)

In the title compound, C11H15N3O3S, the dihedral angle between the five- and six-membered rings is 1.13 (18)°. The ethyl­methane­sulfonamide group is in a (+)synclinal conformation. In the crystal, inter­molecular N—H⋯O and C—H⋯O hydrogen-bond inter­actions link mol­ecules into zigzag ribbons parallel to the b axis. The ribbons are further connected by C—H⋯π inter­actions.

Related literature

For the biological activity of pyrrolo­pyrazinone derivatives, see: Dubis et al. (1995[Dubis, E., Dubis, A., Nawrot, J., Winiecki, Z. & Poplawski, J. (1995). Proceedings of the 1st International Conference on Insects, Insects-Chemical, Physiological and Environmental Aspects, Ládek-Zdrój, University of Wroclaw, Poland.]); Micheli et al. (2008[Micheli, F., Bertani, B., Bozzoli, A., Crippa, L., Cavanni, P., Di Fabio, R., Donati, D., Marzorati, P., Merlo, G., Paio, A., Perugini, L. & Zarantonello, P. (2008). Bioorg. Med. Chem. Lett. 18, 1804-1809.]); Wang et al. (2004[Wang, F., Wang, J. & Zhang, S. (2004). Molecules, 9, 574-582.]); Zöllinger et al. (2007[Zöllinger, M., Kelter, G., Fiebig, H.-H. & Lindel, T. (2007). Bioorg. Med. Chem. Lett. 17, 346-349.]). For standard bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C11H15N3O3S

  • Mr = 269.33

  • Monoclinic, P 21 /c

  • a = 5.492 (1) Å

  • b = 20.631 (4) Å

  • c = 11.212 (2) Å

  • β = 99.953 (6)°

  • V = 1251.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.26 mm−1

  • T = 113 K

  • 0.18 × 0.12 × 0.10 mm

Data collection
  • Rigaku Saturn CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.954, Tmax = 0.974

  • 9267 measured reflections

  • 2969 independent reflections

  • 2499 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.105

  • S = 1.05

  • 2969 reflections

  • 169 parameters

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

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.46 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the N2/C4–C7 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H1N3⋯O1i 0.82 (2) 1.99 (2) 2.7923 (18) 168 (2)
C4—H4A⋯O3ii 0.95 2.36 3.258 (2) 157
C8—H8ACg1iii 0.99 2.96 3.5153 (19) 116
Symmetry codes: (i) -x+2, -y+1, -z+1; (ii) [x-1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) x+1, y, z.

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Pyrrolopyrazinone compounds have been found to possess antitumor activity (Zöllinger et al., 2007), antifeedant effect on storage pests (Dubis et al., 1995) and to be potent and selective non-competitive mGluR5 antagonists (Micheli et al., 2008). Due to the interesting biological activities of pyrrolopyrazinone compounds, the title compound, which may have an improved analgesic activity (Wang et al., 2004), was synthesized and its crystal structure is reported here.

In the title compound (Fig. 1), the nine non-hydrogen atoms of the pyrrolopyrazine ring system are nearly coplanar (r.m.s. deviation 0.0107 (2) Å) and the dihedral angle between the five and six membered rings is 1.13 (18)°. The ethylmethanesulfonamide group (C8–C10/N3/S1/O2–O3) is in (+)-synclinal conformation, as indicated by the C1–N1–C8–C9 torsion angle of 83.75 (16)°. The dihedral angle between the mean planes through C8/C9/C10 and N3/C9/S1 is 79.58 (19)°. The bond lengths are in normal ranges (Allen et al., 1997). In the crystal structure (Fig. 2), centrosymmetrically related molecules are linked by N—H···O hydrogen bonds (Table 1) into dimers forming fourteen-membered rings with R22(14) motifs (Bernstein et al., 1995). Adjacent dimers are linked by C—H···O hydrogen interactions into zigzag ribbons running parallel to the b axis. The crystal packing is further stabilized by inter-ribbon C—H···π interactions (Table 1; Cg1 is the centroid of the N2/C4–C7 ring).

Related literature top

For the biological activity of pyrrolopyrazinone derivatives, see: Dubis et al. (1995); Micheli et al. (2008); Wang et al. (2004); Zöllinger et al. (2007). For standard bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared by reacting 2-(2-aminoethyl)-3-hydroxy-3-methyl-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one (2.39 mmol) and methanesulfonyl chloride (4.76 mmol) in pyridine (2 ml) for 4 h. The reaction mixture was then poured into ice cold water and the solid obtained was filtered and washed thoroughly with water and then dissolved in aqueous NaHCO3 solution. Filtration and then the acidification with dilute HCl gave the title compound as precipitate, which was then filtered and dried. Colourless block-shaped single crystals of the title compound suitable for X-ray structure determination were recrystalized from a dichloromethane/methanol solution (9.5:0.5 v/v) on slow evaporation of the solvent at room temperature after several days.

Refinement top

The amide H atom was located in a difference Fourier map and refined isotropically. The remaining H atoms were placed in calculated positions with d(C—H) = 0.95 Å for aromatic, 0.99 for CH2 and 0.98 Å for CH3 atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups. The highest residual electron density peak is located at 0.64 Å from C7 and the deepest hole is located at 0.74 Å from S1.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the a axis. Hydrogen bonds are drawn as dashed lines.
N-[2-(3-Methyl-1-oxo-1,2-dihydropyrrolo[1,2-a]pyrazin-2- yl)ethyl]methanesulfonamide top
Crystal data top
C11H15N3O3SF(000) = 568
Mr = 269.33Dx = 1.430 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2969 reflections
a = 5.492 (1) Åθ = 2.0–27.9°
b = 20.631 (4) ŵ = 0.26 mm1
c = 11.212 (2) ÅT = 113 K
β = 99.953 (6)°Block, colourless
V = 1251.3 (4) Å30.18 × 0.12 × 0.10 mm
Z = 4
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2969 independent reflections
Radiation source: rotating anode2499 reflections with I > 2σ(I)
Multilayer monochromatorRint = 0.036
Detector resolution: 14.63 pixels mm-1θmax = 27.9°, θmin = 2.0°
ω and ϕ scansh = 67
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 2726
Tmin = 0.954, Tmax = 0.974l = 1414
9267 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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.058P)2 + 0.0584P]
where P = (Fo2 + 2Fc2)/3
2969 reflections(Δ/σ)max = 0.001
169 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.46 e Å3
Crystal data top
C11H15N3O3SV = 1251.3 (4) Å3
Mr = 269.33Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.492 (1) ŵ = 0.26 mm1
b = 20.631 (4) ÅT = 113 K
c = 11.212 (2) Å0.18 × 0.12 × 0.10 mm
β = 99.953 (6)°
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2969 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
2499 reflections with I > 2σ(I)
Tmin = 0.954, Tmax = 0.974Rint = 0.036
9267 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.105H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.22 e Å3
2969 reflectionsΔρmin = 0.46 e Å3
169 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 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 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
S10.99680 (7)0.594929 (18)0.15089 (3)0.02298 (13)
O10.7267 (2)0.54127 (5)0.61880 (10)0.0287 (3)
O21.2319 (2)0.57634 (7)0.12187 (11)0.0358 (3)
O30.9462 (2)0.66268 (6)0.16584 (12)0.0391 (3)
N10.7215 (2)0.63970 (6)0.52476 (11)0.0204 (3)
N20.3756 (2)0.68495 (6)0.65521 (11)0.0210 (3)
N30.9639 (3)0.55700 (7)0.27108 (13)0.0291 (3)
H1N31.063 (4)0.5283 (10)0.2942 (19)0.042 (6)*
C10.6456 (3)0.59733 (7)0.60737 (14)0.0212 (3)
C20.6279 (3)0.70370 (7)0.50739 (14)0.0211 (3)
C30.4595 (3)0.72539 (7)0.57091 (13)0.0222 (3)
H3A0.39700.76830.55870.027*
C40.2052 (3)0.69648 (8)0.72848 (15)0.0273 (4)
H4A0.11370.73530.73180.033*
C50.1905 (3)0.64143 (8)0.79670 (15)0.0305 (4)
H5A0.08720.63600.85570.037*
C60.3529 (3)0.59492 (7)0.76456 (14)0.0251 (4)
H6A0.37890.55240.79700.030*
C70.4690 (3)0.62255 (7)0.67623 (14)0.0214 (3)
C80.9055 (3)0.61459 (8)0.45521 (14)0.0230 (3)
H8A1.02420.58630.50790.028*
H8B0.99890.65120.42820.028*
C90.7814 (3)0.57612 (7)0.34506 (14)0.0240 (3)
H9A0.70180.53700.37210.029*
H9B0.65150.60290.29620.029*
C100.7647 (3)0.56615 (9)0.03536 (15)0.0304 (4)
H10A0.77390.58930.04010.046*
H10B0.60240.57350.05800.046*
H10C0.78830.51960.02370.046*
C110.7287 (3)0.74663 (8)0.41881 (14)0.0267 (4)
H11A0.63900.78790.41100.040*
H11B0.70810.72520.33970.040*
H11C0.90470.75470.44810.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0228 (2)0.0234 (2)0.0228 (2)0.00198 (15)0.00438 (15)0.00159 (14)
O10.0331 (7)0.0212 (6)0.0301 (6)0.0054 (5)0.0009 (5)0.0038 (4)
O20.0215 (6)0.0569 (8)0.0305 (7)0.0040 (6)0.0083 (5)0.0009 (6)
O30.0553 (9)0.0209 (6)0.0401 (7)0.0029 (6)0.0049 (6)0.0035 (5)
N10.0229 (7)0.0194 (6)0.0188 (6)0.0010 (5)0.0036 (5)0.0001 (5)
N20.0229 (7)0.0194 (6)0.0202 (6)0.0007 (5)0.0024 (5)0.0013 (5)
N30.0360 (9)0.0285 (7)0.0253 (7)0.0150 (7)0.0128 (6)0.0074 (6)
C10.0220 (8)0.0197 (7)0.0196 (7)0.0011 (6)0.0030 (6)0.0012 (5)
C20.0240 (8)0.0184 (7)0.0194 (7)0.0029 (6)0.0004 (6)0.0007 (5)
C30.0266 (8)0.0167 (7)0.0226 (7)0.0002 (6)0.0024 (6)0.0014 (6)
C40.0254 (9)0.0306 (8)0.0272 (8)0.0007 (7)0.0081 (7)0.0049 (7)
C50.0311 (10)0.0349 (9)0.0265 (9)0.0065 (7)0.0074 (7)0.0029 (7)
C60.0301 (9)0.0248 (8)0.0196 (8)0.0065 (7)0.0022 (6)0.0007 (6)
C70.0237 (8)0.0197 (7)0.0192 (7)0.0016 (6)0.0009 (6)0.0001 (6)
C80.0204 (8)0.0245 (7)0.0242 (8)0.0014 (6)0.0043 (6)0.0004 (6)
C90.0253 (9)0.0249 (8)0.0232 (8)0.0021 (6)0.0080 (6)0.0010 (6)
C100.0217 (9)0.0424 (10)0.0272 (9)0.0040 (7)0.0046 (7)0.0043 (7)
C110.0316 (9)0.0227 (8)0.0259 (8)0.0020 (7)0.0053 (7)0.0033 (6)
Geometric parameters (Å, º) top
S1—O21.4371 (12)C4—C51.380 (2)
S1—O31.4405 (12)C4—H4A0.9500
S1—N31.5952 (14)C5—C61.399 (2)
S1—C101.7563 (17)C5—H5A0.9500
O1—C11.2378 (17)C6—C71.389 (2)
N1—C11.3890 (19)C6—H6A0.9500
N1—C21.4179 (19)C8—C91.526 (2)
N1—C81.4731 (19)C8—H8A0.9900
N2—C41.3687 (19)C8—H8B0.9900
N2—C71.3907 (19)C9—H9A0.9900
N2—C31.3973 (19)C9—H9B0.9900
N3—C91.4616 (19)C10—H10A0.9800
N3—H1N30.82 (2)C10—H10B0.9800
C1—C71.438 (2)C10—H10C0.9800
C2—C31.338 (2)C11—H11A0.9800
C2—C111.506 (2)C11—H11B0.9800
C3—H3A0.9500C11—H11C0.9800
O2—S1—O3118.97 (8)C7—C6—C5107.08 (14)
O2—S1—N3107.32 (8)C7—C6—H6A126.5
O3—S1—N3108.98 (8)C5—C6—H6A126.5
O2—S1—C10107.98 (8)C6—C7—N2107.42 (13)
O3—S1—C10106.48 (8)C6—C7—C1132.03 (14)
N3—S1—C10106.47 (8)N2—C7—C1120.49 (13)
C1—N1—C2122.30 (13)N1—C8—C9111.09 (13)
C1—N1—C8116.35 (12)N1—C8—H8A109.4
C2—N1—C8121.35 (12)C9—C8—H8A109.4
C4—N2—C7109.25 (13)N1—C8—H8B109.4
C4—N2—C3129.93 (13)C9—C8—H8B109.4
C7—N2—C3120.82 (13)H8A—C8—H8B108.0
C9—N3—S1122.41 (12)N3—C9—C8110.19 (13)
C9—N3—H1N3120.1 (14)N3—C9—H9A109.6
S1—N3—H1N3117.2 (14)C8—C9—H9A109.6
O1—C1—N1120.88 (14)N3—C9—H9B109.6
O1—C1—C7123.13 (14)C8—C9—H9B109.6
N1—C1—C7115.99 (13)H9A—C9—H9B108.1
C3—C2—N1120.38 (13)S1—C10—H10A109.5
C3—C2—C11121.40 (14)S1—C10—H10B109.5
N1—C2—C11118.19 (13)H10A—C10—H10B109.5
C2—C3—N2119.95 (14)S1—C10—H10C109.5
C2—C3—H3A120.0H10A—C10—H10C109.5
N2—C3—H3A120.0H10B—C10—H10C109.5
N2—C4—C5107.54 (14)C2—C11—H11A109.5
N2—C4—H4A126.2C2—C11—H11B109.5
C5—C4—H4A126.2H11A—C11—H11B109.5
C4—C5—C6108.71 (15)C2—C11—H11C109.5
C4—C5—H5A125.6H11A—C11—H11C109.5
C6—C5—H5A125.6H11B—C11—H11C109.5
O2—S1—N3—C9163.37 (13)N2—C4—C5—C60.44 (19)
O3—S1—N3—C933.29 (16)C4—C5—C6—C70.49 (19)
C10—S1—N3—C981.20 (15)C5—C6—C7—N20.36 (17)
C2—N1—C1—O1178.48 (14)C5—C6—C7—C1177.60 (16)
C8—N1—C1—O11.4 (2)C4—N2—C7—C60.09 (17)
C2—N1—C1—C71.1 (2)C3—N2—C7—C6179.43 (13)
C8—N1—C1—C7179.04 (12)C4—N2—C7—C1177.72 (14)
C1—N1—C2—C30.4 (2)C3—N2—C7—C12.9 (2)
C8—N1—C2—C3179.51 (14)O1—C1—C7—C60.1 (3)
C1—N1—C2—C11177.87 (14)N1—C1—C7—C6179.63 (15)
C8—N1—C2—C112.2 (2)O1—C1—C7—N2176.85 (14)
N1—C2—C3—N20.2 (2)N1—C1—C7—N22.7 (2)
C11—C2—C3—N2177.95 (14)C1—N1—C8—C983.75 (16)
C4—N2—C3—C2179.39 (16)C2—N1—C8—C996.15 (16)
C7—N2—C3—C21.4 (2)S1—N3—C9—C8100.44 (15)
C7—N2—C4—C50.21 (18)N1—C8—C9—N3174.55 (12)
C3—N2—C4—C5179.05 (15)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the N2/C4–C7 ring.
D—H···AD—HH···AD···AD—H···A
N3—H1N3···O1i0.82 (2)1.99 (2)2.7923 (18)168 (2)
C4—H4A···O3ii0.952.363.258 (2)157
C8—H8A···Cg1iii0.992.963.5153 (19)116
Symmetry codes: (i) x+2, y+1, z+1; (ii) x1, y+3/2, z+1/2; (iii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC11H15N3O3S
Mr269.33
Crystal system, space groupMonoclinic, P21/c
Temperature (K)113
a, b, c (Å)5.492 (1), 20.631 (4), 11.212 (2)
β (°) 99.953 (6)
V3)1251.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.26
Crystal size (mm)0.18 × 0.12 × 0.10
Data collection
DiffractometerRigaku Saturn CCD area-detector
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.954, 0.974
No. of measured, independent and
observed [I > 2σ(I)] reflections
9267, 2969, 2499
Rint0.036
(sin θ/λ)max1)0.658
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.105, 1.05
No. of reflections2969
No. of parameters169
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.22, 0.46

Computer programs: CrystalClear (Rigaku, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the N2/C4–C7 ring.
D—H···AD—HH···AD···AD—H···A
N3—H1N3···O1i0.82 (2)1.99 (2)2.7923 (18)168 (2)
C4—H4A···O3ii0.952.363.258 (2)157
C8—H8A···Cg1iii0.992.963.5153 (19)116
Symmetry codes: (i) x+2, y+1, z+1; (ii) x1, y+3/2, z+1/2; (iii) x+1, y, z.
 

Footnotes

Additional correspondence author, e-mail: suchada.c@psu.ac.th. Thomson Reuters ResearcherID: A-5085-2009.

Acknowledgements

STK thanks Dr Song Haibin of The State Key Laboratory of Elemento-Organic Chemistry, Nankai University, for the data collection. PY is grateful to Tianjin University of Science & Technology for a research grant (No. 2009 0431).

References

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