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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 8| August 2011| Pages o1967-o1968
doi:10.1107/S1600536811026237

Ethyl 2-[(carbamo­thioyl­amino)­imino]­propano­ate

Charlane C. Corrêa,a* José Eugênio J.C. Graúdo,a Luiz Fernando C. de Oliveira,a Mauro V. de Almeidab and Renata Diniza

aNúcleo de Espectroscopia e Estrutura Molecular (NEEM), Department of Chemistry, Federal University of Juiz de Fora, Minas Gerais 36036-900, Brazil, and bDepartment of Chemistry, Federal University of Juiz de Fora, Minas Gerais 36036-900, Brazil
*Correspondence e-mail: charcorrea@gmail.com

(Received 7 June 2011; accepted 1 July 2011; online 9 July 2011)

The title compound, C6H11N3O2S, consists of a roughly planar mol­ecule (r.m.s deviation from planarity = 0.077 Å for the non-H atoms) and has the S atom in an anti position to the imine N atom. This N atom is the acceptor of a strongly bent inter­nal N—H⋯N hydrogen bond donated by the amino group. In the crystal, mol­ecules are arranged in undulating layers parallel to (010). The mol­ecules are linked via inter­molecular amino–carboxyl N—H⋯O hydrogen bonds, forming chains parallel to [001]. The chains are cross-linked by Ncarbazone—H⋯S and C—H⋯S inter­actions, forming infinite sheets.

Related literature

For the synthesis of thio­semicarbazones, see: Gupta & Narayana (1997[Gupta, R. P. & Narayana, N. L. (1997). Pharm. Acta Helv. 72, 43-45.]); Li et al. (1998[Li, J., Chen, S., Li, X., Niu, C. & Doyle, T. W. (1998). Tetrahedron, 54, 393-400.]); Tarasconi et al. (2000[Tarasconi, P., Capacchi, S., Pelosi, G., Cornia, M., Albertini, R., Bonati, A., Dall'Aglio, P. P., Lunghi, P. & Pinelli, S. (2000). Bioorg. Med. Chem. 8, 157-162.]); Holla et al. (2003[Holla, B. S., Malini, K. V., Rao, B. S., Sarojini, B. K. & Kumari, N. S. (2003). Eur. J. Med. Chem. 38, 313-318.]); Shailendra et al. (2003[Shailendra, N. B., Naqvi, F. & Azam, A. (2003). Bioorg. Med. Chem. Lett. 13, 689-692.]). For the synthesis, crystal structures and applications of thio­semicarbazones, see: West et al. (1993[West, D. X., Liberta, A., Padhye, S. B., Chikate, R. C., Sonawane, P. B., Kumbhar, A. S. & Yerande, R. G. (1993). Coord. Chem. Rev. 123, 49-71.]); Casas et al. (2000[Casas, J. S., Tasende, M. S. G. & Sordo, J. (2000). Coord. Chem. Rev. 209, 197-261.]); Beraldo (2004[Beraldo, H. (2004). Quím. Nova, 27, 461-471.]); Tenório et al. (2005[Tenório, R. P., Góes, A. J. S., de Lima, A. J. S., de Faria, A. R., Alves, A. J. & de Aquino, T. M. (2005). Quím. Nova, 28, 1030-1037.]). For graph-set notation, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]).

[Scheme 1]

Experimental

Crystal data

  • C6H11N3O2S

  • Mr = 189.24

  • Monoclinic, C 2/c

  • a = 16.682 (3) Å

  • b = 7.2558 (15) Å

  • c = 17.317 (4) Å

  • β = 116.63 (3)°

  • V = 1873.8 (7) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 297 K

  • 0.56 × 0.27 × 0.12 mm
Data collection

  • Bruker–Nonius KappaCCD diffractometer

  • 15270 measured reflections

  • 2133 independent reflections

  • 1785 reflections with I > 2σ(I)

  • Rint = 0.021
Refinement

  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.092

  • S = 1.08

  • 2133 reflections

  • 123 parameters

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

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1N⋯N3 0.84 (2) 2.24 (2) 2.610 (2) 107 (2)
N1—H2N⋯O2i 0.88 (3) 2.08 (3) 2.954 (2) 172 (2)
N2—H3N⋯S1ii 0.85 (2) 2.78 (2) 3.623 (2) 172 (2)
C3—H3C⋯S1ii 0.96 2.82 3.611 (2) 141
Symmetry codes: (i) [x, -y+1, z-{\script{1\over 2}}]; (ii) [-x, y, -z+{\script{1\over 2}}].

Data collection: COLLECT (Hooft, 1999[Hooft, R. W. (1999). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]) and SCALEPACK; 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-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811026237/qk2014sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811026237/qk2014Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811026237/qk2014Isup3.cml

checkCIF report


Comment top

Thiosemicarbazones are a class of substances known for their biological and chemical properties, such as antiviral, antibacterial, antiprotozoal and antitumor activity (West et al., 1993). The enzyme ribonucleoside diphosphate reductase (RDR) (Beraldo, 2004) is an object of attack by thiosemicarbazones, which relates to their tumor control properties. One background for the biological activity of thiosemicarbazones is certainly their ability to form chelates with transition metal ions. The synthesis of thiosemicarbazones is described in several works in the literature (Gupta & Narayana, 1997; Li et al., 1998; Tarasconi et al., 2000; Holla et al., 2003; Shailendra et al., 2003). In context with potential biological activity the crystal structure determination of the title compound, ethyl pyruvate thiosemicarbazone (scheme 1), was of interest. The compound may also be interesting as ligand in coordination chemistry.

Figure 1 shows the ORTEP representation of the asymmetric unit of the title compound. The compound features a fairly planar molecule with a r.m.s deviation from planarity 0.077 Å for the non-hydrogen atoms. The sulfur atom is in anti position to the imine nitrogen N3. The bond lengths in the N—C(S)—N fragment indicate delocalization of the π electrons due to the fact that the C—N and C—S bonds are shorter than tipycal single bonds (around 1.47 and 1.73 Å, respectively) and bigger than corresponding double bonds (around 1.29 and 1.55 Å, respectively) (Casas et al., 2000; Tenório et al., 2005). The molecule is stabilized by the strongly bent intramolecular hydrogen N1—H1n···N3, N1···N3 = 2.610 (2) Å (Table 1).

In the crystal lattice the molecules are arranged in undulating layers parallel to (010). Via the intermolecular hydrogen bond N1—H2n···O2i the molecules are linked to form continuous chains parallel to [001], as visualized in Figure 2. The graph-set representation for this arrangement is N = C(8), (Etter et al., 1990). Each two of these chains are mutually crosslinked by the weak interactions N2—H3n···S1ii, N2···S1ii = 3.623 (2) Å, and C3—H3c···S1ii, C3···S1ii = 3.611 (2) Å, to form infinite ribbons along the c axis, see Table 1 and Fig. 2.

Related literature top

For the synthesis of thiosemicarbazones, see: Gupta & Narayana (1997); Li et al. (1998); Tarasconi et al. (2000); Holla et al. (2003); Shailendra et al. (2003). For the synthesis, crystal structures and applications of thiosemicarbazones, see: West et al. (1993); Casas et al. (2000); Beraldo (2004); Tenório et al. (2005). For graph-set notation, see: Etter et al. (1990).

Experimental top

For preparation of the title compound, 0.188 g of ethyl pyruvate (1.62 mmol) was added to 15 ml of a water-methanol solution (1:2) of thiosemicarbazide hydrochloride (1.48 g, 1.62 mmol) and the mixture was heated at 80 °C for 3 h. After few days, colorless crystals formed at room temperature and were isolated. M.p.: 145 °C. Elemental analysis gave the following results: Calcd. for C6H11O2N3S: C 38.08, H 5.86, N 22.21%; found: C 39.69; H 6.62; N 22.93%.

IR spectral data were obtained with a Bomem MB-102 spectrometer fitted with a CsI beam splitter, using KBr disks and a spectral resolution of 4 cm-1. The main absorption bands are (cm-1): 3442–3204 (νNH); 1709 (νCO); 1600 (νNH + νCN + νCC); 1498 (νCOasym); 1370 (νCN); 1173 (νCOsym); 1119, 1024 (νCS) ; 1105 (νCOC).

Refinement top

C-bound H atoms were included in the riding model approximation with C—H = 0.96 Å and Uiso(H) = 1.5×Uequ(C) for CH3, and 0.97 Å Uiso(H) = 1.2×Uequ(C) for CH2. H atoms of nitrogen atoms were located from an electron density map and were refined unrestrained in x,y,z, and Uiso.

Computing details top

Data collection: COLLECT (Hooft, 1999); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of ethyl pyruvate thiosemicarbazone showing 50% displacement ellipsoids.
[Figure 2] Fig. 2. View of a ribbon of hydrogen bonded molecules in the crystal structure of ethyl pyruvate thiosemicarbazone.
Ethyl 2-[(carbamothioylamino)imino]propanoate top
Crystal data top
C6H11N3O2SF(000) = 800
Mr = 189.24Dx = 1.342 Mg m−3
Monoclinic, C2/cMelting point: 418 K
Hall symbol: -C 2ycMo Kα radiation, λ = 0.71073 Å
a = 16.682 (3) ÅCell parameters from 106 reflections
b = 7.2558 (15) Åθ = 4.7–22.6°
c = 17.317 (4) ŵ = 0.31 mm−1
β = 116.63 (3)°T = 297 K
V = 1873.8 (7) Å3Prism, colourless
Z = 80.56 × 0.27 × 0.12 mm
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1785 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.021
Horizonally mounted graphite crystal monochromatorθmax = 27.5°, θmin = 5.3°
Detector resolution: 9 pixels mm-1h = −21→21
ω and ϕ scansk = −9→9
15270 measured reflectionsl = −22→22
2133 independent reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.092 w = 1/[σ2(Fo2) + (0.0423P)2 + 1.1077P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
2133 reflectionsΔρmax = 0.21 e Å−3
123 parametersΔρmin = −0.26 e Å−3
Crystal data top
C6H11N3O2SV = 1873.8 (7) Å3
Mr = 189.24Z = 8
Monoclinic, C2/cMo Kα radiation
a = 16.682 (3) ŵ = 0.31 mm−1
b = 7.2558 (15) ÅT = 297 K
c = 17.317 (4) Å0.56 × 0.27 × 0.12 mm
β = 116.63 (3)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer		1785 reflections with I > 2σ(I)
15270 measured reflectionsRint = 0.021
2133 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0330 restraints
wR(F2) = 0.092H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.21 e Å−3
2133 reflectionsΔρmin = −0.26 e Å−3
123 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
S10.07816 (2)0.66899 (7)0.18273 (2)0.05007 (15)
O10.36286 (7)0.42826 (16)0.55879 (6)0.0453 (3)
O20.29362 (8)0.4511 (2)0.64308 (7)0.0599 (4)
N30.21829 (8)0.52146 (17)0.42323 (7)0.0363 (3)
N20.14791 (8)0.57872 (18)0.34827 (7)0.0394 (3)
N10.23628 (9)0.5179 (2)0.28107 (9)0.0541 (4)
C20.21056 (9)0.5244 (2)0.49384 (9)0.0365 (3)
C10.15936 (9)0.5823 (2)0.27447 (9)0.0368 (3)
C40.29221 (9)0.4639 (2)0.57299 (9)0.0378 (3)
C30.13145 (10)0.5866 (3)0.50629 (11)0.0507 (4)
H3A0.12980.71890.50690.076*
H3B0.13650.53980.56010.076*
H3C0.07730.54100.45980.076*
C60.51684 (12)0.3513 (3)0.60556 (14)0.0644 (5)
H6A0.49770.25880.56130.097*
H6B0.57130.31220.65370.097*
H6C0.52720.46500.58310.097*
C50.44536 (10)0.3796 (3)0.63469 (11)0.0503 (4)
H5A0.43680.26770.66070.060*
H5B0.46260.47770.67720.060*
H1N0.2740 (14)0.476 (3)0.3288 (14)0.061 (6)*
H3N0.0969 (12)0.612 (2)0.3430 (11)0.045 (4)*
H2N0.2477 (13)0.525 (3)0.2361 (14)0.060 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0402 (2)0.0741 (3)0.0365 (2)0.00740 (18)0.01775 (16)0.01065 (17)
O10.0387 (5)0.0663 (7)0.0337 (5)0.0055 (5)0.0186 (4)0.0026 (5)
O20.0558 (7)0.0988 (10)0.0322 (5)0.0012 (6)0.0260 (5)−0.0006 (6)
N30.0358 (6)0.0444 (6)0.0318 (5)−0.0029 (5)0.0179 (5)−0.0016 (5)
N20.0344 (6)0.0552 (8)0.0339 (6)0.0028 (5)0.0200 (5)0.0027 (5)
N10.0421 (7)0.0910 (12)0.0369 (7)0.0153 (7)0.0246 (6)0.0118 (7)
C20.0385 (7)0.0425 (7)0.0343 (6)−0.0052 (6)0.0213 (6)−0.0043 (6)
C10.0352 (6)0.0456 (8)0.0333 (6)−0.0042 (6)0.0185 (5)−0.0004 (6)
C40.0415 (7)0.0440 (8)0.0334 (7)−0.0053 (6)0.0216 (6)−0.0056 (6)
C30.0431 (8)0.0733 (11)0.0454 (8)0.0025 (8)0.0284 (7)−0.0012 (8)
C60.0447 (9)0.0665 (12)0.0798 (13)0.0050 (8)0.0259 (9)−0.0007 (10)
C50.0430 (8)0.0574 (10)0.0432 (8)0.0009 (7)0.0128 (7)0.0070 (7)
Geometric parameters (Å, º) top
S1—C11.6808 (16)N1—H1N0.84 (2)
O1—C41.3325 (17)N1—H2N0.88 (2)
O1—C51.4577 (19)N2—H3N0.85 (2)
O2—C41.2069 (17)C3—H3A0.9600
N3—C21.2860 (17)C3—H3B0.9600
N3—N21.3675 (17)C3—H3C0.9600
N2—C11.3745 (17)C5—H5A0.9700
N1—C11.3217 (19)C5—H5B0.9700
C2—C31.4989 (19)C6—H6A0.9600
C2—C41.501 (2)C6—H6B0.9600
C6—C51.503 (2)C6—H6C0.9600
C4—O1—C5115.86 (11)C2—C3—H3A109.00
C2—N3—N2119.23 (12)C2—C3—H3B109.00
N3—N2—C1118.06 (11)C2—C3—H3C109.00
N3—C2—C3127.72 (14)H3A—C3—H3B109.00
N3—C2—C4115.25 (12)H3A—C3—H3C109.00
C3—C2—C4117.00 (12)H3B—C3—H3C109.00
N1—C1—N2116.55 (13)O1—C5—H5A110.00
N1—C1—S1123.64 (11)O1—C5—H5B110.00
N2—C1—S1119.80 (11)C6—C5—H5A110.00
O2—C4—O1123.40 (14)C6—C5—H5B110.00
O2—C4—C2122.77 (13)H5A—C5—H5B108.00
O1—C4—C2113.83 (11)C5—C6—H6A109.00
O1—C5—C6107.52 (14)C5—C6—H6B109.00
C1—N1—H1N118.9 (17)C5—C6—H6C109.00
C1—N1—H2N119.2 (15)H6A—C6—H6B109.00
H1N—N1—H2N122 (2)H6A—C6—H6C109.00
C1—N2—H3N116.4 (12)H6B—C6—H6C109.00
N3—N2—H3N125.5 (12)
C5—O1—C4—O2−2.7 (2)N2—N3—C2—C3−0.6 (2)
C5—O1—C4—C2176.48 (14)N2—N3—C2—C4−178.40 (13)
C4—O1—C5—C6−178.14 (15)N3—C2—C4—O14.43 (19)
C1—N2—N3—C2177.04 (14)N3—C2—C4—O2−176.40 (15)
N3—N2—C1—S1−174.66 (11)C3—C2—C4—O1−173.59 (15)
N3—N2—C1—N14.4 (2)C3—C2—C4—O25.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···N30.84 (2)2.24 (2)2.610 (2)107 (2)
N1—H2N···O2i0.88 (3)2.08 (3)2.954 (2)172 (2)
N2—H3N···S1ii0.85 (2)2.78 (2)3.623 (2)172 (2)
C3—H3C···S1ii0.962.823.611 (2)141
Symmetry codes: (i) x, −y+1, z−1/2; (ii) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formulaC6H11N3O2S
Mr189.24
Crystal system, space groupMonoclinic, C2/c
Temperature (K)297
a, b, c (Å)16.682 (3), 7.2558 (15), 17.317 (4)
β (°) 116.63 (3)
V (Å3)1873.8 (7)
Z8
Radiation typeMo Kα
µ (mm−1)0.31
Crystal size (mm)0.56 × 0.27 × 0.12
Data collection
DiffractometerBruker–Nonius KappaCCD
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		15270, 2133, 1785
Rint0.021
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.092, 1.08
No. of reflections2133
No. of parameters123
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.21, −0.26

Computer programs: COLLECT (Hooft, 1999), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···N30.84 (2)2.24 (2)2.610 (2)107 (2)
N1—H2N···O2i0.88 (3)2.08 (3)2.954 (2)172 (2)
N2—H3N···S1ii0.85 (2)2.78 (2)3.623 (2)172 (2)
C3—H3C···S1ii0.962.823.611 (2)141
Symmetry codes: (i) x, −y+1, z−1/2; (ii) −x, y, −z+1/2.
 

Acknowledgements

The authors thank CNPq, CAPES, and FAPEMIG (Brazilian agencies) for financial support and also R. G. Bastos (LDRX-IF/UFF) for the X-ray diffraction facilities.

References

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ISSN: 2056-9890
Volume 67| Part 8| August 2011| Pages o1967-o1968
doi:10.1107/S1600536811026237
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