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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 69| Part 3| March 2013| Page o434
doi:10.1107/S1600536813004881

2-Methyl­sulfanyl-1,2,4-triazolo[1,5-a]quinazoline-5(4H)-thione

Rashad Al-Salahi,a Mohamed Marzouk,a Mohamed A. Al-Omar,a Abd El-Galil E. Amr,b,c‡ Seik Weng Ngd,e and Edward R. T. Tiekinkd*

aDepartment of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, bDrug Exploration & Development Chair (DEDC), College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia, cApplied Organic Chemistry Department, National Research Center, Dokki 12622, Cairo, Egypt, dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and eChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 19 February 2013; accepted 19 February 2013; online 23 February 2013)

In the title compound, C10H8N4S2, comprising fused six-, six- and five-membered rings, the mol­ecule is close to being planar (r.m.s. deviation of the non-H atoms = 0.041 Å). The S-bound methyl group is folded away from the single N atom of the triazole ring and the NH group of the six-membered ring, allowing for the formation of centrosymmetric eight-membered {⋯HNCN}2 synthons in the crystal. The resulting inversion dimers are connected into supra­molecular stacks aligned along the b-axis direction by π–π inter­actions [centroid–centroid distances = 3.6531 (12) and 3.7182 (12) Å].

Related literature

For background to the biological activity of triazoloquinazolines, see: Pierce et al. (2004[Pierce, A. C., Arnost, M., Davies, R. J., Forster, C. J., Galullo, V., Grey, R., Ledeboer, M., Tian, S.-K., Xu, J., Binch, H., Ledford, B., Messersmith, D., Nanthakumar, S. & Jayaraj, A. (2004). Chem. Abstr. 141, 23537.]); Al-Salahi & Geffken (2010[Al-Salahi, R. & Geffken, D. (2010). Molecules, 15, 7016-7034.], 2011[Al-Salahi, R. & Geffken, D. (2011). Synth. Commun. 41, 3512-3523.]); Al-Salahi et al. (2011[Al-Salahi, R., Geffken, D. & Koellner, M. (2011). Chem. Pharm. Bull. 59, 730-733.], 2013[Al-Salahi, R., Gamal-Eldeen, A. M., Alanazi, A. M., Al-Omar, M. A., Marzouk, M. A. & Fouda, M. M. G. (2013). Molecules, 18, 1434-1446.]).

[Scheme 1]

Experimental

Crystal data

  • C10H8N4S2

  • Mr = 248.32

  • Monoclinic, P 21 /c

  • a = 10.5414 (11) Å

  • b = 4.9335 (6) Å

  • c = 20.0943 (19) Å

  • β = 99.127 (10)°

  • V = 1031.79 (19) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.49 mm−1

  • T = 295 K

  • 0.30 × 0.15 × 0.05 mm
Data collection

  • Agilent SuperNova Dual diffractometer with an Atlas detector

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]) Tmin = 0.864, Tmax = 1.000

  • 5096 measured reflections

  • 2389 independent reflections

  • 1667 reflections with I > 2σ(I)

  • Rint = 0.035
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.098

  • S = 0.93

  • 2389 reflections

  • 149 parameters

  • 1 restraint

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

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯N4i 0.87 (1) 2.07 (1) 2.931 (2) 171 (2)
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813004881/hb7045sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813004881/hb7045Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813004881/hb7045Isup3.cml

checkCIF report


Comment top

A series of triazoloquinazolines, which originated from N-cyanoimidocarbonates as synthons, has been shown to exhibit diverse biological activities. For example, 2-aminoalkyl(aryl)-[1,2,4]triazolo[1,5-a]quinazolin-5-ones were found to be potent proteinkinase inhibitors (Pierce et al., 2004), the 2,5-dialkoxy-[1,2,4]triazolo[1,5-a]quinazolines have shown activity as adenosine antagonists (Al-Salahi & Geffken, 2010; Al-Salahi & Geffken, 2011; Al-Salahi et al., 2011) whereas the related alkylated 1,2,4-triazolo[1,5-a]quinazolin-5-ones have been proven to be cytotoxic and to possess anti-inflammatory activity (Al-Salahi et al., 2013). In view of the aforementioned biological activities of diverse triazoloquinazolines and in continuation of our ongoing studies dealing with the chemistry of N-cyanoimidocarbonates and their precursors, we report herein the results of our study of thionation of 2-methylsulfanyl-4H-[1,2,4]triazolo[1,5-a]quinazolin-5-one to obtain (I). Herein, the crystal and molecular structure of the title compound is described.

The molecular structure of (I), Fig. 1, comprises fused six-, six- and five membered rings that are co-planar with the r.m.s. deviation of the 13 non-hydrogen atoms being 0.028 Å. Indeed, the entire molecule is close to planar (r.m.s. = 0.041 Å) with the maximum deviations from the least-squares plane being 0.047 (2) Å for atom N4 and -0.072 (2) for methyl-C10. The S-bound methyl group is orientated towards the N3 atom and may be regarded as anti to the thione-S2 atom.

The most prominent feature of the crystal packing is the formation of centrosymmetric eight-membered {···HNCN}2 synthons, Table 1. These are connected into stacks along the b axis by π—π interactions whereby the triazole ring straddles the benzene [inter-centroid distance = 3.6531 (12) Å, angle of inclination = 3.04 (11)°] and pyrimidine [3.7182 (12) Å, 1.90 (10)°] rings of translationally related molecules, Fig. 2 (symmetry operation x, -1 + y, z]. There are no specific intermolecular interactions between stacks, Fig. 3.

Related literature top

For background to the biological activity of triazoloquinazolines, see: Pierce et al. (2004); Al-Salahi & Geffken (2010, 2011); Al-Salahi et al. (2011, 2013).

Experimental top

2-Methylsulfanyl-4H-[1,2,4]triazolo[1,5-a]quinazolin-5-one (1 mmol) was refluxed with phosphorous pentasulfide (1 mmol) in absolute pyridine (5 ml) for 2 h. After cooling the reaction mixture, it was poured into ice/water. The yellow precipitate that separated was filtered off and washed thoroughly with water. Recrystallization as yellow prisms was from a mixture of toluene and DMF (8:2 v/v).

Refinement top

The C-bound H atoms were geometrically placed (C—H = 0.93–0.96 Å) and refined as riding with Uiso(H) = 1.2–1.5Ueq(C). The N-bound-H atom was refined with the distance retsraint N—H = 0.88±0.01 Å and free Uiso.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); 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, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 35% probability level.
[Figure 2] Fig. 2. A view of the supramolecular chain along the b axis in (I) sustained by N—H···N and π—π interactions, shown as blue and purple dashed lines, respectively.
[Figure 3] Fig. 3. view in projection down the b axis of the crystal packing in (I). The N—H···N and π—π interactions are shown as blue and purple dashed lines, respectively.
2-Methylsulfanyl-1,2,4-triazolo[1,5-a]quinazoline-5(4H)-thione top
Crystal data top
C10H8N4S2F(000) = 512
Mr = 248.32Dx = 1.599 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1314 reflections
a = 10.5414 (11) Åθ = 3.1–27.5°
b = 4.9335 (6) ŵ = 0.49 mm−1
c = 20.0943 (19) ÅT = 295 K
β = 99.127 (10)°Prism, yellow
V = 1031.79 (19) Å30.30 × 0.15 × 0.05 mm
Z = 4
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector		2389 independent reflections
Radiation source: SuperNova (Mo) X-ray Source1667 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.035
Detector resolution: 10.4041 pixels mm-1θmax = 27.6°, θmin = 3.1°
ω scanh = −13→12
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)		k = −5→6
Tmin = 0.864, Tmax = 1.000l = −22→26
5096 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) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 0.93 w = 1/[σ2(Fo2) + (0.0452P)2]
where P = (Fo2 + 2Fc2)/3
2389 reflections(Δ/σ)max = 0.001
149 parametersΔρmax = 0.28 e Å−3
1 restraintΔρmin = −0.29 e Å−3
Crystal data top
C10H8N4S2V = 1031.79 (19) Å3
Mr = 248.32Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.5414 (11) ŵ = 0.49 mm−1
b = 4.9335 (6) ÅT = 295 K
c = 20.0943 (19) Å0.30 × 0.15 × 0.05 mm
β = 99.127 (10)°
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector		2389 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)		1667 reflections with I > 2σ(I)
Tmin = 0.864, Tmax = 1.000Rint = 0.035
5096 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0401 restraint
wR(F2) = 0.098H atoms treated by a mixture of independent and constrained refinement
S = 0.93Δρmax = 0.28 e Å−3
2389 reflectionsΔρmin = −0.29 e Å−3
149 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
S10.57415 (5)0.09061 (12)0.69579 (3)0.03633 (18)
S20.69330 (6)1.14441 (14)0.43364 (3)0.0455 (2)
N10.63890 (16)0.7597 (4)0.51388 (8)0.0334 (4)
H10.5735 (15)0.728 (5)0.4828 (9)0.052 (7)*
N20.75333 (14)0.6491 (3)0.61961 (8)0.0288 (4)
N30.74549 (16)0.4772 (3)0.67308 (8)0.0309 (4)
N40.57690 (15)0.4139 (4)0.58757 (8)0.0325 (4)
C10.72154 (19)0.9632 (4)0.50311 (10)0.0316 (5)
C20.83231 (19)1.0021 (4)0.55680 (10)0.0306 (5)
C30.92564 (19)1.1992 (5)0.55164 (11)0.0363 (5)
H30.91691.31020.51380.044*
C41.0296 (2)1.2317 (5)0.60125 (11)0.0403 (6)
H41.09061.36400.59700.048*
C51.04387 (19)1.0665 (5)0.65804 (11)0.0385 (5)
H51.11511.08830.69140.046*
C60.95443 (19)0.8723 (4)0.66552 (10)0.0358 (5)
H60.96440.76260.70360.043*
C70.84829 (18)0.8415 (4)0.61517 (10)0.0292 (5)
C80.65228 (18)0.6076 (4)0.57102 (9)0.0294 (5)
C90.63785 (18)0.3432 (4)0.65066 (10)0.0296 (5)
C100.6908 (2)0.0885 (5)0.77103 (11)0.0474 (6)
H10A0.6676−0.04560.80160.071*
H10B0.69350.26370.79200.071*
H10C0.77380.04610.75990.071*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0370 (3)0.0390 (4)0.0320 (3)−0.0018 (3)0.0023 (2)0.0034 (3)
S20.0496 (4)0.0525 (4)0.0330 (3)−0.0007 (3)0.0019 (3)0.0110 (3)
N10.0337 (9)0.0388 (11)0.0247 (9)−0.0014 (9)−0.0046 (8)0.0023 (8)
N20.0291 (8)0.0321 (10)0.0237 (8)0.0019 (8)−0.0006 (7)0.0006 (8)
N30.0339 (9)0.0321 (10)0.0256 (9)0.0011 (8)0.0015 (7)0.0028 (8)
N40.0328 (9)0.0369 (11)0.0266 (9)0.0011 (9)0.0007 (7)0.0016 (8)
C10.0351 (11)0.0320 (12)0.0285 (11)0.0054 (10)0.0070 (9)−0.0012 (9)
C20.0329 (10)0.0314 (12)0.0282 (11)0.0062 (10)0.0069 (9)−0.0035 (9)
C30.0380 (11)0.0367 (13)0.0354 (12)−0.0001 (11)0.0091 (10)−0.0006 (10)
C40.0366 (12)0.0394 (14)0.0457 (13)−0.0061 (11)0.0090 (10)−0.0064 (12)
C50.0306 (11)0.0436 (14)0.0387 (12)0.0001 (11)−0.0024 (10)−0.0089 (11)
C60.0363 (11)0.0380 (13)0.0313 (11)0.0050 (10)−0.0007 (9)−0.0009 (10)
C70.0287 (10)0.0304 (11)0.0283 (11)0.0020 (9)0.0044 (8)−0.0040 (9)
C80.0316 (10)0.0316 (12)0.0234 (10)0.0038 (10)−0.0007 (8)−0.0027 (9)
C90.0310 (10)0.0302 (12)0.0270 (10)0.0044 (10)0.0029 (9)−0.0020 (9)
C100.0511 (14)0.0587 (17)0.0299 (12)−0.0044 (13)−0.0007 (10)0.0097 (12)
Geometric parameters (Å, º) top
S1—C91.738 (2)C2—C31.399 (3)
S1—C101.791 (2)C2—C71.403 (3)
S2—C11.645 (2)C3—C41.369 (3)
N1—C81.360 (2)C3—H30.9300
N1—C11.369 (3)C4—C51.391 (3)
N1—H10.868 (10)C4—H40.9300
N2—C81.342 (2)C5—C61.369 (3)
N2—N31.381 (2)C5—H50.9300
N2—C71.392 (2)C6—C71.393 (3)
N3—C91.329 (2)C6—H60.9300
N4—C81.319 (3)C10—H10A0.9600
N4—C91.372 (2)C10—H10B0.9600
C1—C21.471 (3)C10—H10C0.9600
C9—S1—C10100.05 (10)C6—C5—C4120.89 (19)
C8—N1—C1123.68 (17)C6—C5—H5119.6
C8—N1—H1118.3 (16)C4—C5—H5119.6
C1—N1—H1118.0 (16)C5—C6—C7119.0 (2)
C8—N2—N3109.51 (16)C5—C6—H6120.5
C8—N2—C7123.58 (17)C7—C6—H6120.5
N3—N2—C7126.91 (15)C6—C7—N2122.05 (19)
C9—N3—N2101.24 (15)C6—C7—C2121.4 (2)
C8—N4—C9101.80 (16)N2—C7—C2116.50 (17)
N1—C1—C2115.51 (18)N4—C8—N2111.57 (18)
N1—C1—S2119.93 (15)N4—C8—N1128.80 (17)
C2—C1—S2124.56 (17)N2—C8—N1119.63 (19)
C3—C2—C7117.51 (18)N3—C9—N4115.88 (18)
C3—C2—C1121.46 (19)N3—C9—S1124.04 (15)
C7—C2—C1121.0 (2)N4—C9—S1120.09 (15)
C4—C3—C2121.2 (2)S1—C10—H10A109.5
C4—C3—H3119.4S1—C10—H10B109.5
C2—C3—H3119.4H10A—C10—H10B109.5
C3—C4—C5119.9 (2)S1—C10—H10C109.5
C3—C4—H4120.0H10A—C10—H10C109.5
C5—C4—H4120.0H10B—C10—H10C109.5
C8—N2—N3—C90.5 (2)C3—C2—C7—C6−1.4 (3)
C7—N2—N3—C9179.49 (18)C1—C2—C7—C6178.41 (19)
C8—N1—C1—C22.8 (3)C3—C2—C7—N2179.17 (17)
C8—N1—C1—S2−177.27 (16)C1—C2—C7—N2−1.0 (3)
N1—C1—C2—C3178.67 (19)C9—N4—C8—N21.2 (2)
S2—C1—C2—C3−1.3 (3)C9—N4—C8—N1−178.6 (2)
N1—C1—C2—C7−1.2 (3)N3—N2—C8—N4−1.2 (2)
S2—C1—C2—C7178.89 (16)C7—N2—C8—N4179.82 (17)
C7—C2—C3—C40.9 (3)N3—N2—C8—N1178.65 (17)
C1—C2—C3—C4−178.9 (2)C7—N2—C8—N1−0.4 (3)
C2—C3—C4—C50.1 (3)C1—N1—C8—N4177.7 (2)
C3—C4—C5—C6−0.6 (3)C1—N1—C8—N2−2.1 (3)
C4—C5—C6—C70.1 (3)N2—N3—C9—N40.3 (2)
C5—C6—C7—N2−179.68 (19)N2—N3—C9—S1179.79 (14)
C5—C6—C7—C21.0 (3)C8—N4—C9—N3−0.9 (2)
C8—N2—C7—C6−177.57 (19)C8—N4—C9—S1179.53 (15)
N3—N2—C7—C63.6 (3)C10—S1—C9—N30.4 (2)
C8—N2—C7—C21.8 (3)C10—S1—C9—N4179.93 (17)
N3—N2—C7—C2−177.02 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N4i0.87 (1)2.07 (1)2.931 (2)171 (2)
Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formulaC10H8N4S2
Mr248.32
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)10.5414 (11), 4.9335 (6), 20.0943 (19)
β (°) 99.127 (10)
V (Å3)1031.79 (19)
Z4
Radiation typeMo Kα
µ (mm−1)0.49
Crystal size (mm)0.30 × 0.15 × 0.05
Data collection
DiffractometerAgilent SuperNova Dual
diffractometer with an Atlas detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2011)
Tmin, Tmax0.864, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections		5096, 2389, 1667
Rint0.035
(sin θ/λ)max (Å−1)0.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.098, 0.93
No. of reflections2389
No. of parameters149
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.28, −0.29

Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N4i0.868 (10)2.072 (11)2.931 (2)171 (2)
Symmetry code: (i) −x+1, −y+1, −z+1.
 

Footnotes

‡Additional correspondence author, e-mail: aamr1963@yahoo.com.

Acknowledgements

The authors are grateful for the sponsorship of the Research Center, College of Pharmacy and the Deanship of Scientific Research, King Saud University. We also thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR-MOHE/SC/12).

References

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 First citationAl-Salahi, R. & Geffken, D. (2010). Molecules, 15, 7016–7034.  CAS Google Scholar
 First citationAl-Salahi, R. & Geffken, D. (2011). Synth. Commun. 41, 3512–3523.  CAS Google Scholar
 First citationAl-Salahi, R., Geffken, D. & Koellner, M. (2011). Chem. Pharm. Bull. 59, 730–733.  Web of Science CAS PubMed Google Scholar
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ISSN: 2056-9890
Volume 69| Part 3| March 2013| Page o434
doi:10.1107/S1600536813004881
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