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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 64| Part 4| April 2008| Page o730
doi:10.1107/S1600536808007150

7-Nitro-5H-1-benzo­thio­pyrano[2,3-b]pyridin-5-one

Muhammad Naeem Khan,a,b M. Nawaz Tahir,c* Misbahul Ain Khan,a Islam Ullah Khand and Muhammad Nadeem Arshadd

aDepartment of Chemistry, Islamia University, Bahawalpur, Pakistan, bApplied Chemistry Research Center, PCSIR Laboratories Complex, Lahore 54600, Pakistan, cUniversity of Sargodha, Department of Physics, Sagrodha, Pakistan, and dGovernment College University, Department of Chemistry, Lahore, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 8 March 2008; accepted 15 March 2008; online 20 March 2008)

In the mol­ecule of the title compound, C12H6N2O3S, the central heterocyclic ring is oriented at dihedral angles of 3.25 (6) and 2.28 (7)° with respect to the benzene and pyridine rings, respectively. The dihedral angle between the benzene and pyridine rings is 5.53 (7)°. In the crystal structure, inter­molecular C—H⋯O hydrogen bonds link the mol­ecules into chains.

Related literature

For general background, see: Acheson et al. (1976[Acheson, M. (1976). An Introduction to the Chemistry of Heterocyclic Compounds, 3rd ed. New York: John Wiley & Sons Inc.]); Lesher et al. (1962[Lesher, G. Y., Froelich, E. J., Gruett, M. D., Bailey, J. H. & Brundage, R. P. (1962). J. Med. Chem. 5, 1063-1065.]); Archer et al. (1982[Archer, S., Miller, K. J., Rej, R., Periana, C. & Fricker, L. (1982). J. Med. Chem. 25, 220-227.], 1988[Archer, S., Pica-Mattoccia, L., Cioli, D., Seyed-Mozaffari, A. & Zayed, A. H. (1988). J. Med. Chem. 31, 254-260.]); Showalter et al. (1988[Showalter, H. D. H., Angelo, M. M., Berman, E. M., Kanter, G. D., Ortwine, D. F., Ross-Kesten, S. G., Sercel, A. D., Turner, W. R., Werbel, L. M., Worth, D. F., Elslager, E. F., Leopold, W. R. & Shillis, J. L. (1988). J. Med. Chem. 31, 1527-1539.]). For related structures, see: Atkinson et al. (2006[Atkinson, P., Findlay, K. S., Kielar, F., Pal, R., Parker, D., Poole, R. A., Puschmann, H., Richardson, S. L., Stenson, P. A., Thompson, A. L. & Yu, J. (2006). Org. Biomol. Chem. 4, 1707-1722.]). For related literature, see: Mann & Reid (1952[Mann, F. G. & Reid, J. A. (1952). J. Chem. Soc. pp. 2057-2062.]); Hidetoshi (1997[Hidetoshi, F. (1997). Heterocycles, 45, 119-127.]); Kurger & Mann (1955[Kurger, S. & Mann, F. G. (1955). J. Chem. Soc. pp. 2755-2763.]). For details of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

[Scheme 1]

Experimental

Crystal data

  • C12H6N2O3S

  • Mr = 258.25

  • Orthorhombic, P c a 21

  • a = 24.822 (2) Å

  • b = 3.8884 (2) Å

  • c = 10.8505 (7) Å

  • V = 1047.28 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 296 (2) K

  • 0.25 × 0.12 × 0.08 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]) Tmin = 0.927, Tmax = 0.976

  • 6571 measured reflections

  • 2491 independent reflections

  • 2038 reflections with I > 2σ(I)

  • Rint = 0.031
Refinement

  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.083

  • S = 1.02

  • 2491 reflections

  • 163 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.21 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1047 Friedel pairs

  • Flack parameter: 0.03 (8)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C3—H3⋯O3i 0.93 2.41 3.275 (3) 155
Symmetry code: (i) [-x+{\script{1\over 2}}, y+1, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc. Madison, Wisconsin, USA.]); 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 PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808007150/hk2433sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808007150/hk2433Isup2.hkl

checkCIF report


Comment top

Pyridine containing compounds are widely distributed in nature. Drugs, dyes, alkoloids (Acheson et al., 1976), nalidixic acid and quinoline (Lesher et al., 1962), which are antibacterial, also contain pyridine rings in their structures. Heteroaromatic antitumor compounds have been prepared in recent years with the hope of increasing pharmacological effects. DNA intercalating agents, which are an important class of antitumor drugs, usually posses planar aromatic and heteroaromatic polycyclic system. Some thioxanthones have also shown effectiveness against tumor (Archer et al., 1982; Archer et al., 1988; Showalter et al., 1988). Heterocyclic compounds having S-atom in their ring can also be used as antioxidative agents.

The title compound, (I), is a member of azathioxanthone. It contains three planar six-membered rings; A (C1—C6), B (S1/C1/C6—C8/C12) and C (N2/C8—C12), in which they are oriented at dihedral angles of A/B = 3.25 (6), A/C = 5.53 (7) and B/C = 2.28 (7) °. So, they are also nearly coplanar. The CCDC search (Allen, 2002) showed that the crystal structure containing a similar skeleton [2-methyl-1-azathioxanthone, (II), (Atkinson et al., 2006)], has been reported, thus it is the only potential candidate for comparison of the bond lengths and angles in (I).

In (I), the S—C bonds are in the range of [1.731 (2)–1.746 (2) Å], while they are between [1.741 (3)–1.743 (3) Å], in (II).

In the crystal structure, intermolecular C—H···O hydrogen bonds (Table 1) link the molecules into chains (Fig. 2). These H-bonds seem to play an effective role in the stabilization of the structure.

Related literature top

For general background, see: Acheson et al. (1976); Lesher et al. (1962); Archer et al. (1982, 1988); Showalter et al. (1988). For related structures, see: Atkinson et al. (2006). For related literature, see: Mann & Reid (1952); Hidetoshi (1997); Kurger & Mann (1955). For details of the Cambridge Structural Database, see: Allen (2002).

Experimental top

A mixture of 2-chloronicotinic acid (1.57 g, 10 mmol) and thiophenol (2 ml) was heated under reflux for 2 h to produce 2-(phenylsulfanyl)pyridine-3- carboxylic acid (Mann & Reid, 1952). The polyphosphoric acid (PPA) (Hidetoshi, 1997) was used to cyclize the produced acid, and 5H-thiochromeno[2,3-b]pyridin- 5-one was obtained. The cyclized product was nitrated using KNO3 and H2SO4 (Kurger & Mann, 1955). Two isomers, 7-nitro-5H-thiochromeno[2,3-b]- pyridin-5-one, (I), and 9-nitro-5H-thiochromeno[2,3-b]pyridin-5-one, (III), were obtained, and they were separated using acetic acid and ethanol, respectively. Crystals suitable for X-ray diffraction were obtained by cooling the saturated solution of (I) in glacial acetic acid.

Refinement top

H atoms were positioned geometrically, with C—H = 0.93 Å for aromatic H and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A partial packing diagram of (I). Hydrogen bonds are shown as dashed lines
7-Nitro-5H-1-benzothiopyrano[2,3-b]pyridin-5-one top
Crystal data top
C12H6N2O3SF(000) = 528
Mr = 258.25Dx = 1.638 Mg m−3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 1444 reflections
a = 24.822 (2) Åθ = 1.7–29.2°
b = 3.8884 (2) ŵ = 0.31 mm−1
c = 10.8505 (7) ÅT = 296 K
V = 1047.28 (12) Å3Prismatic, light yellow
Z = 40.25 × 0.12 × 0.08 mm
Data collection top
Bruker KappaAPEXII CCD
diffractometer		2491 independent reflections
Radiation source: fine-focus sealed tube2038 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
Detector resolution: 7.5 pixels mm-1θmax = 29.1°, θmin = 2.5°
ω scansh = −31→32
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		k = −5→5
Tmin = 0.927, Tmax = 0.976l = −14→13
6571 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.083 w = 1/[σ2(Fo2) + (0.0408P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max < 0.001
2491 reflectionsΔρmax = 0.21 e Å−3
163 parametersΔρmin = −0.21 e Å−3
1 restraintAbsolute structure: Flack (1983), 1047 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.03 (8)
Crystal data top
C12H6N2O3SV = 1047.28 (12) Å3
Mr = 258.25Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 24.822 (2) ŵ = 0.31 mm−1
b = 3.8884 (2) ÅT = 296 K
c = 10.8505 (7) Å0.25 × 0.12 × 0.08 mm
Data collection top
Bruker KappaAPEXII CCD
diffractometer		2491 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		2038 reflections with I > 2σ(I)
Tmin = 0.927, Tmax = 0.976Rint = 0.031
6571 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.083Δρmax = 0.21 e Å−3
S = 1.02Δρmin = −0.21 e Å−3
2491 reflectionsAbsolute structure: Flack (1983), 1047 Friedel pairs
163 parametersAbsolute structure parameter: 0.03 (8)
1 restraint
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
S10.39024 (2)0.42115 (12)0.39781 (5)0.03676 (14)
O10.12993 (7)0.2278 (5)0.3058 (2)0.0694 (6)
O20.15811 (8)−0.0812 (6)0.1535 (2)0.0660 (6)
O30.34609 (7)−0.1679 (5)0.06332 (15)0.0491 (5)
N10.16584 (8)0.1026 (5)0.2436 (2)0.0433 (5)
N20.48349 (8)0.3607 (5)0.3026 (2)0.0452 (5)
C10.32646 (8)0.3151 (5)0.34578 (19)0.0285 (4)
C20.28373 (9)0.4190 (5)0.4212 (2)0.0353 (5)
H20.29100.53380.49460.042*
C30.23123 (8)0.3542 (5)0.3888 (2)0.0354 (5)
H30.20290.42640.43840.042*
C40.22173 (9)0.1777 (5)0.2796 (2)0.0336 (5)
C50.26260 (9)0.0689 (5)0.2047 (2)0.0321 (5)
H50.2547−0.05170.13290.039*
C60.31604 (8)0.1380 (5)0.23549 (19)0.0282 (4)
C70.35825 (9)0.0152 (5)0.1503 (2)0.0314 (5)
C80.41454 (9)0.1140 (5)0.17226 (19)0.0313 (4)
C90.45386 (10)0.0293 (6)0.0858 (2)0.0440 (6)
H90.4444−0.08170.01300.053*
C100.50665 (11)0.1111 (6)0.1089 (3)0.0522 (7)
H100.53340.05780.05190.063*
C110.51950 (10)0.2730 (7)0.2176 (3)0.0528 (7)
H110.55550.32430.23260.063*
C120.43215 (9)0.2827 (5)0.27847 (19)0.0333 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0323 (3)0.0429 (3)0.0350 (3)−0.0032 (2)−0.0032 (3)−0.0060 (3)
O10.0317 (10)0.0938 (13)0.0825 (15)0.0109 (11)0.0082 (11)−0.0090 (13)
O20.0366 (11)0.0929 (15)0.0685 (14)−0.0117 (10)−0.0072 (11)−0.0173 (12)
O30.0395 (10)0.0618 (11)0.0458 (10)−0.0038 (8)0.0042 (8)−0.0236 (9)
N10.0265 (11)0.0552 (13)0.0481 (12)0.0024 (10)0.0022 (9)0.0093 (11)
N20.0309 (10)0.0479 (11)0.0569 (13)−0.0041 (9)−0.0028 (10)0.0007 (10)
C10.0267 (10)0.0267 (9)0.0322 (10)−0.0001 (8)−0.0014 (9)0.0027 (8)
C20.0412 (13)0.0361 (10)0.0285 (13)0.0011 (9)0.0020 (10)−0.0011 (9)
C30.0311 (10)0.0384 (10)0.0366 (12)0.0055 (8)0.0114 (10)0.0004 (12)
C40.0261 (11)0.0352 (10)0.0395 (12)0.0001 (9)−0.0012 (9)0.0088 (10)
C50.0308 (12)0.0350 (10)0.0305 (10)−0.0006 (9)−0.0009 (9)0.0020 (9)
C60.0282 (12)0.0273 (9)0.0290 (10)−0.0011 (8)−0.0007 (9)0.0035 (8)
C70.0307 (12)0.0349 (10)0.0285 (11)−0.0004 (9)0.0023 (10)0.0008 (9)
C80.0295 (11)0.0308 (10)0.0337 (11)0.0023 (9)0.0017 (10)0.0027 (9)
C90.0391 (14)0.0458 (12)0.0471 (14)0.0004 (11)0.0097 (11)0.0000 (11)
C100.0334 (15)0.0552 (15)0.0681 (18)−0.0003 (11)0.0193 (13)−0.0021 (14)
C110.0279 (13)0.0528 (14)0.078 (2)−0.0015 (11)0.0018 (14)0.0024 (15)
C120.0284 (12)0.0301 (10)0.0414 (12)−0.0003 (9)−0.0018 (10)0.0033 (9)
Geometric parameters (Å, º) top
S1—C11.731 (2)C5—C61.394 (3)
S1—C121.746 (2)C5—H50.9300
N1—O11.219 (3)C7—O31.220 (3)
N1—O21.226 (3)C7—C81.469 (3)
N1—C41.471 (3)C7—C61.476 (3)
N2—C111.329 (3)C8—C91.393 (3)
C1—C21.400 (3)C9—C101.372 (4)
C1—C61.405 (3)C9—H90.9300
C2—C31.373 (3)C10—C111.374 (4)
C2—H20.9300C10—H100.9300
C3—H30.9300C11—H110.9300
C4—C31.389 (3)C12—N21.336 (3)
C5—C41.367 (3)C12—C81.396 (3)
C1—S1—C12103.27 (10)C5—C6—C7117.57 (19)
O1—N1—O2124.0 (2)C1—C6—C7124.14 (18)
O1—N1—C4117.6 (2)O3—C7—C8120.90 (19)
O2—N1—C4118.4 (2)O3—C7—C6119.84 (19)
C11—N2—C12116.6 (2)C8—C7—C6119.27 (18)
C2—C1—C6120.01 (19)C9—C8—C12116.6 (2)
C2—C1—S1115.70 (16)C9—C8—C7119.7 (2)
C6—C1—S1124.28 (16)C12—C8—C7123.69 (19)
C3—C2—C1121.1 (2)C10—C9—C8119.4 (2)
C3—C2—H2119.5C10—C9—H9120.3
C1—C2—H2119.5C8—C9—H9120.3
C2—C3—C4118.1 (2)C9—C10—C11119.0 (2)
C2—C3—H3121.0C9—C10—H10120.5
C4—C3—H3121.0C11—C10—H10120.5
C5—C4—C3122.3 (2)N2—C11—C10123.8 (2)
C5—C4—N1118.7 (2)N2—C11—H11118.1
C3—C4—N1119.0 (2)C10—C11—H11118.1
C4—C5—C6120.3 (2)N2—C12—C8124.5 (2)
C4—C5—H5119.9N2—C12—S1110.68 (17)
C6—C5—H5119.9C8—C12—S1124.79 (17)
C5—C6—C1118.29 (19)
C12—S1—C1—C2−175.98 (15)C4—C5—C6—C11.2 (3)
C12—S1—C1—C63.75 (19)C4—C5—C6—C7−179.64 (18)
C1—S1—C12—N2177.32 (15)O3—C7—C6—C5−6.9 (3)
C1—S1—C12—C8−2.6 (2)C8—C7—C6—C5173.52 (18)
O1—N1—C4—C5−173.6 (2)O3—C7—C6—C1172.23 (19)
O2—N1—C4—C56.4 (3)C8—C7—C6—C1−7.3 (3)
O1—N1—C4—C36.8 (3)O3—C7—C8—C97.0 (3)
O2—N1—C4—C3−173.2 (2)C6—C7—C8—C9−173.5 (2)
C12—N2—C11—C100.2 (4)O3—C7—C8—C12−171.0 (2)
C6—C1—C2—C3−0.7 (3)C6—C7—C8—C128.6 (3)
S1—C1—C2—C3179.00 (16)C7—C8—C9—C10−177.6 (2)
S1—C1—C6—C5179.95 (15)C12—C8—C9—C100.5 (3)
C2—C1—C6—C5−0.3 (3)C8—C9—C10—C110.4 (4)
S1—C1—C6—C70.8 (3)C9—C10—C11—N2−0.8 (4)
C2—C1—C6—C7−179.47 (18)S1—C12—N2—C11−179.05 (18)
C1—C2—C3—C41.0 (3)C8—C12—N2—C110.8 (3)
C5—C4—C3—C2−0.1 (3)N2—C12—C8—C9−1.2 (3)
N1—C4—C3—C2179.43 (19)S1—C12—C8—C9178.70 (16)
C6—C5—C4—C3−1.0 (3)N2—C12—C8—C7176.82 (19)
C6—C5—C4—N1179.49 (18)S1—C12—C8—C7−3.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.932.413.275 (3)155
Symmetry code: (i) −x+1/2, y+1, z+1/2.

Experimental details

Crystal data
Chemical formulaC12H6N2O3S
Mr258.25
Crystal system, space groupOrthorhombic, Pca21
Temperature (K)296
a, b, c (Å)24.822 (2), 3.8884 (2), 10.8505 (7)
V (Å3)1047.28 (12)
Z4
Radiation typeMo Kα
µ (mm−1)0.31
Crystal size (mm)0.25 × 0.12 × 0.08
Data collection
DiffractometerBruker KappaAPEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.927, 0.976
No. of measured, independent and
observed [I > 2σ(I)] reflections		6571, 2491, 2038
Rint0.031
(sin θ/λ)max (Å−1)0.684
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.083, 1.02
No. of reflections2491
No. of parameters163
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.21, −0.21
Absolute structureFlack (1983), 1047 Friedel pairs
Absolute structure parameter0.03 (8)

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O3i0.932.4103.275 (3)155.00
Symmetry code: (i) −x+1/2, y+1, z+1/2.
 

Acknowledgements

The authors acknowledge the Higher Education Com­mision, Islamabad, Pakistan, for funding the purchase of the diffractometer.

References

First citationAcheson, M. (1976). An Introduction to the Chemistry of Heterocyclic Compounds, 3rd ed. New York: John Wiley & Sons Inc.  Google Scholar
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ISSN: 2056-9890
Volume 64| Part 4| April 2008| Page o730
doi:10.1107/S1600536808007150
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