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Acta Cryst. (2008). E64, o1076-o1077    [ doi:10.1107/S1600536808013883 ]

3-[1-(4-Isobutylphenyl)ethyl]-6-(4-methylphenyl)-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole

H.-K. Fun, S. R. Jebas, I. A. Razak, K. V. Sujith, P. S. Patil, B. Kalluraya and S. M. Dharmaprakash

Abstract top

In the title compound, C22H24N4S, the methylphenyl and isobutylphenyl rings are inclined at an angle of 79.98 (1)° and they form dihedral angles of 4.59 (1) and 75.47 (1)°, respectively, with the triazolothiadiazole unit. An intramolecular C-H...S hydrogen bond generates an S(5) ring motif. The crystal structure is stabilized by intermolecular C-H...N hydrogen bonds and weak C-H...[pi] and [pi]-[pi] interactions [centroid-centroid distances between the thiadiazole ring and a symmetry-related phenyl ring and between the triazole ring and the phenyl ring range from 3.5680 (8) to 3.7313 (8) Å].

Comment top

Triazoles and their heterocyclic derivatives represent an interesting class of compounds possessing a wide spectrum of biological activity, such as anticancer, anticonvulsant, analgesic, antibacterial, anthelmintic, antitubercular and anti-inflammatory activities (Holla et al., 2003; Bekircan & Bektas, 2006; Zhou et al., 2007). Similarly 1, 3,4-thiadiazoles were also found to possess antitumor, anti-inflammatory, antibacterial, antifungal, anticonvulsant and antitubercular properties (Bhat et al., 2004; Mathew et al., 2007). Thus triazolothiadiazole systems may be viewed as cyclic analogues of two very important components, which often display diverse pharmacological properties. Triazolothiadiazoles obtained by fusing the biolabile 1,2,4-triazole and 1,3,4-thiadiazole rings together have been reported to possess similar biological properties (Karthikeyan et al., 2007; Chaturvedi et al., 1988; Shawali & Sayed 2006) and the crystal structure of the title triazolothiadiazole compound is reported here.

Bond lengths and angles in the title compound (Fig 1) have normal values (Allen et al., 1987). The triazolothiadiazole ring is planar with the maximum deviation of 0.016 (2)Å for atom C7. The planes through the C1—C6 and C11—C16 rings form dihedral angles of 4.59 (1)° and 75.47 (1)° respectively, with the triazolothiadiazole unit. This is also planar with a dihedral angle of 1.34 (2) ° between the two five membered rings. A weak intramolecular C—H···S hydrogen bond generates an S(5) ring motif (Bernstein et al., (1995) and contributes to the planarity of the 4-methylphenyl-triazolothiadiazole portion of the molecule.

The crystal packing is stabilized by intermolecular C—H···N hydrogen bonds and a weak C—H···π interaction involving the C11—C16 ring (centroid Cg1, Table 1). π–π interactions are observed between the thiadiazole ring (S1/C7/N1—N2/C8) and the symmetry related phenyl rings (C1—C6) and between the triazole ring and the phenyl ring (C1—C6) with centroid to centroid distances ranging from 3.5680 (8)–3.7313 (8)Å [symmetry codes:1-X,-Y,1-Z;2-X, -Y,1-Z].

Related literature top

For information on the biological activity of triazole derivatives, thiadiazoles and triazolothiadiazole compounds, see: Holla et al. (2003); Bekircan & Bektas (2006); Zhou et al. (2007); Bhat et al. (2004); Mathew et al. (2007); Karthikeyan et al. (2007); Chaturvedi et al. (1988); Shawali & Sayed (2006). For details of hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). Cg1 is the centroid of the C11–C16 ring.

For related literature, see: Tayseer et al. (2002).

Experimental top

A mixture of 4-amino-3-mercapto-5-[1-(4-isobutylphenyl)ethyl]-1, 2,4-triazole (0.01 mol), p-toluic acid (0.01 mol) and 10 ml POCl3 was refluxed on a water bath for about 9 h. Excess of POCl3 was removed under reduced pressure. The reaction mixture was cooled, poured into crushed ice, and neutralized with aqueous ammonia. The resulting solid product was filtered off, washed with water, dried, and recrystallized from a mixture of ethanol and dimethylformamide, 1/1, v/v. (Yield 61%; m.p. 134–1360 C). Analysis (%) for C22H24N4S found (calculated): C 70.16 (70.21), H 6.31 (6.38), N 14.78 (14.89).

Refinement top

H atoms were positioned geometrically [C–H = 0.93–0.98 Å] and refined using a riding model, with Uiso(H) = -1.2 to -1.5Ueq(C). A rotating-group model was used for the methyl groups.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 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, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Dashed lines indicate hydrogen bonds.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed along the c axis. Hydrogen bonds are shown as dashed lines.
3-[1-(4-Isobutylphenyl)ethyl]-6-(4-methylphenyl)-1,2,4- triazolo[3,4-b][1,3,4]thiadiazole top
Crystal data top
C22H24N4SZ = 2
Mr = 376.51F000 = 400
Triclinic, P1Dx = 1.270 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.2545 (1) ÅCell parameters from 5597 reflections
b = 8.1764 (1) Åθ = 2.6–32.0º
c = 17.6556 (3) ŵ = 0.18 mm−1
α = 97.539 (1)ºT = 100.0 (1) K
β = 96.712 (1)ºBlock, colourless
γ = 106.024 (1)º0.46 × 0.20 × 0.18 mm
V = 984.90 (2) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		5687 independent reflections
Radiation source: fine-focus sealed tube4391 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.029
T = 100.0(1) Kθmax = 30.0º
φ and ω scansθmin = 1.2º
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		h = −10→8
Tmin = 0.922, Tmax = 0.969k = −11→11
15868 measured reflectionsl = −24→24
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)] = 0.047H-atom parameters constrained
wR(F2) = 0.142  w = 1/[σ2(Fo2) + (0.0792P)2 + 0.0947P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
5687 reflectionsΔρmax = 0.45 e Å−3
248 parametersΔρmin = −0.38 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C22H24N4Sγ = 106.024 (1)º
Mr = 376.51V = 984.90 (2) Å3
Triclinic, P1Z = 2
a = 7.2545 (1) ÅMo Kα
b = 8.1764 (1) ŵ = 0.18 mm−1
c = 17.6556 (3) ÅT = 100.0 (1) K
α = 97.539 (1)º0.46 × 0.20 × 0.18 mm
β = 96.712 (1)º
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		5687 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		4391 reflections with I > 2σ(I)
Tmin = 0.922, Tmax = 0.969Rint = 0.029
15868 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.047248 parameters
wR(F2) = 0.142H-atom parameters constrained
S = 1.08Δρmax = 0.45 e Å−3
5687 reflectionsΔρmin = −0.38 e Å−3
Special details top

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

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
S10.65630 (5)0.70616 (5)0.50456 (2)0.02030 (11)
N10.77613 (18)0.91957 (15)0.40935 (7)0.0187 (3)
N20.73966 (17)0.75288 (15)0.37235 (7)0.0177 (3)
N30.6927 (2)0.50811 (16)0.29652 (7)0.0237 (3)
N40.6461 (2)0.47006 (16)0.36878 (7)0.0236 (3)
C10.8328 (2)1.23186 (19)0.51493 (8)0.0197 (3)
H1A0.86731.24040.46620.024*
C20.8563 (2)1.3798 (2)0.56768 (9)0.0218 (3)
H2A0.90891.48710.55410.026*
C30.8029 (2)1.3718 (2)0.64094 (8)0.0212 (3)
C40.7242 (2)1.2089 (2)0.65980 (9)0.0237 (3)
H4A0.68591.20040.70800.028*
C50.7022 (2)1.0597 (2)0.60774 (8)0.0222 (3)
H5A0.65050.95240.62140.027*
C60.7572 (2)1.06958 (18)0.53493 (8)0.0174 (3)
C70.7360 (2)0.91381 (18)0.47910 (8)0.0172 (3)
C80.6765 (2)0.62112 (18)0.41226 (8)0.0193 (3)
C90.7476 (2)0.67599 (19)0.29953 (8)0.0202 (3)
C100.8042 (2)0.7724 (2)0.23493 (9)0.0233 (3)
H10A0.92270.86740.25570.028*
C110.6460 (2)0.85129 (19)0.20767 (8)0.0220 (3)
C120.4859 (2)0.75782 (19)0.15229 (8)0.0228 (3)
H12A0.47510.64470.13090.027*
C130.3422 (2)0.8308 (2)0.12848 (9)0.0245 (3)
H13A0.23790.76640.09070.029*
C140.3510 (2)0.99849 (19)0.15996 (9)0.0251 (3)
C150.5107 (3)1.0916 (2)0.21594 (9)0.0289 (4)
H15A0.51971.20350.23840.035*
C160.6563 (3)1.0200 (2)0.23864 (9)0.0274 (4)
H16A0.76281.08570.27520.033*
C170.8301 (3)1.5347 (2)0.69710 (9)0.0274 (3)
H17A0.76321.50740.73970.041*
H17B0.77831.61280.67150.041*
H17C0.96611.58790.71600.041*
C180.8520 (3)0.6536 (2)0.17039 (9)0.0289 (4)
H18A0.96930.62810.18850.043*
H18B0.86940.71010.12630.043*
H18C0.74720.54810.15600.043*
C190.1932 (3)1.0768 (2)0.13430 (10)0.0296 (4)
H19A0.12901.09940.17800.036*
H19B0.09730.99280.09470.036*
C200.2641 (3)1.2447 (2)0.10233 (10)0.0312 (4)
H20A0.35291.33160.14400.037*
C210.3738 (3)1.2215 (3)0.03589 (11)0.0437 (5)
H21A0.48381.18460.05320.066*
H21B0.41761.32930.01780.066*
H21C0.28971.1360−0.00550.066*
C220.0920 (3)1.3099 (2)0.07796 (11)0.0419 (5)
H22A0.13721.41560.05840.063*
H22B0.02981.33030.12190.063*
H22C0.00081.22490.03830.063*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0225 (2)0.02041 (19)0.01790 (18)0.00448 (15)0.00473 (14)0.00591 (13)
N10.0200 (6)0.0182 (6)0.0187 (6)0.0067 (5)0.0031 (5)0.0038 (5)
N20.0192 (6)0.0172 (6)0.0168 (6)0.0051 (5)0.0027 (5)0.0044 (4)
N30.0277 (7)0.0225 (6)0.0202 (6)0.0061 (6)0.0036 (5)0.0041 (5)
N40.0282 (7)0.0208 (6)0.0214 (6)0.0052 (5)0.0053 (5)0.0059 (5)
C10.0205 (7)0.0228 (7)0.0177 (7)0.0083 (6)0.0047 (6)0.0045 (6)
C20.0218 (7)0.0214 (7)0.0231 (7)0.0077 (6)0.0035 (6)0.0047 (6)
C30.0189 (7)0.0263 (7)0.0194 (7)0.0101 (6)0.0011 (6)0.0018 (6)
C40.0258 (8)0.0294 (8)0.0172 (7)0.0096 (7)0.0051 (6)0.0039 (6)
C50.0250 (8)0.0234 (7)0.0194 (7)0.0071 (6)0.0051 (6)0.0061 (6)
C60.0153 (7)0.0208 (7)0.0169 (6)0.0073 (6)0.0012 (5)0.0031 (5)
C70.0146 (6)0.0197 (7)0.0180 (7)0.0052 (5)0.0019 (5)0.0056 (5)
C80.0185 (7)0.0195 (7)0.0201 (7)0.0043 (6)0.0035 (6)0.0064 (5)
C90.0219 (7)0.0204 (7)0.0177 (7)0.0067 (6)0.0016 (6)0.0020 (5)
C100.0273 (8)0.0236 (7)0.0187 (7)0.0064 (6)0.0051 (6)0.0040 (6)
C110.0302 (8)0.0198 (7)0.0163 (6)0.0055 (6)0.0069 (6)0.0057 (5)
C120.0314 (8)0.0183 (7)0.0189 (7)0.0062 (6)0.0071 (6)0.0032 (5)
C130.0310 (8)0.0214 (7)0.0189 (7)0.0045 (6)0.0039 (6)0.0031 (6)
C140.0357 (9)0.0217 (7)0.0201 (7)0.0095 (7)0.0065 (7)0.0072 (6)
C150.0447 (10)0.0174 (7)0.0231 (8)0.0091 (7)0.0002 (7)0.0030 (6)
C160.0370 (9)0.0202 (7)0.0205 (7)0.0032 (7)−0.0003 (7)0.0028 (6)
C170.0321 (9)0.0292 (8)0.0207 (7)0.0132 (7)0.0005 (7)−0.0020 (6)
C180.0312 (9)0.0353 (9)0.0238 (8)0.0140 (7)0.0078 (7)0.0060 (7)
C190.0377 (9)0.0277 (8)0.0259 (8)0.0134 (7)0.0049 (7)0.0053 (6)
C200.0482 (11)0.0217 (7)0.0235 (8)0.0140 (8)−0.0024 (7)0.0024 (6)
C210.0660 (14)0.0411 (11)0.0307 (9)0.0211 (10)0.0107 (9)0.0158 (8)
C220.0616 (13)0.0302 (9)0.0340 (10)0.0234 (9)−0.0081 (9)−0.0010 (7)
Geometric parameters (Å, °) top
S1—C81.7248 (15)C12—C131.388 (2)
S1—C71.7714 (14)C12—H12A0.9300
N1—C71.3018 (18)C13—C141.391 (2)
N1—N21.3716 (17)C13—H13A0.9300
N2—C81.3672 (18)C14—C151.395 (2)
N2—C91.3699 (18)C14—C191.511 (2)
N3—C91.3113 (19)C15—C161.387 (2)
N3—N41.4092 (18)C15—H15A0.9300
N4—C81.3133 (19)C16—H16A0.9300
C1—C21.383 (2)C17—H17A0.9600
C1—C61.397 (2)C17—H17B0.9600
C1—H1A0.9300C17—H17C0.9600
C2—C31.397 (2)C18—H18A0.9600
C2—H2A0.9300C18—H18B0.9600
C3—C41.397 (2)C18—H18C0.9600
C3—C171.503 (2)C19—C201.533 (2)
C4—C51.386 (2)C19—H19A0.9700
C4—H4A0.9300C19—H19B0.9700
C5—C61.395 (2)C20—C211.513 (3)
C5—H5A0.9300C20—C221.527 (3)
C6—C71.464 (2)C20—H20A0.9800
C9—C101.503 (2)C21—H21A0.9600
C10—C111.525 (2)C21—H21B0.9600
C10—C181.533 (2)C21—H21C0.9600
C10—H10A0.9800C22—H22A0.9600
C11—C121.392 (2)C22—H22B0.9600
C11—C161.394 (2)C22—H22C0.9600
C8—S1—C787.77 (7)C12—C13—H13A119.3
C7—N1—N2107.74 (12)C14—C13—H13A119.3
C8—N2—C9105.94 (12)C13—C14—C15117.59 (15)
C8—N2—N1118.63 (12)C13—C14—C19121.14 (15)
C9—N2—N1135.41 (12)C15—C14—C19121.27 (14)
C9—N3—N4109.48 (12)C16—C15—C14121.08 (14)
C8—N4—N3104.93 (12)C16—C15—H15A119.5
C2—C1—C6119.97 (13)C14—C15—H15A119.5
C2—C1—H1A120.0C15—C16—C11121.19 (15)
C6—C1—H1A120.0C15—C16—H16A119.4
C1—C2—C3121.54 (14)C11—C16—H16A119.4
C1—C2—H2A119.2C3—C17—H17A109.5
C3—C2—H2A119.2C3—C17—H17B109.5
C4—C3—C2118.01 (14)H17A—C17—H17B109.5
C4—C3—C17121.60 (14)C3—C17—H17C109.5
C2—C3—C17120.39 (14)H17A—C17—H17C109.5
C5—C4—C3120.94 (14)H17B—C17—H17C109.5
C5—C4—H4A119.5C10—C18—H18A109.5
C3—C4—H4A119.5C10—C18—H18B109.5
C4—C5—C6120.46 (14)H18A—C18—H18B109.5
C4—C5—H5A119.8C10—C18—H18C109.5
C6—C5—H5A119.8H18A—C18—H18C109.5
C5—C6—C1119.07 (13)H18B—C18—H18C109.5
C5—C6—C7121.42 (13)C14—C19—C20114.77 (15)
C1—C6—C7119.50 (12)C14—C19—H19A108.6
N1—C7—C6122.53 (13)C20—C19—H19A108.6
N1—C7—S1116.63 (11)C14—C19—H19B108.6
C6—C7—S1120.84 (10)C20—C19—H19B108.6
N4—C8—N2111.28 (13)H19A—C19—H19B107.6
N4—C8—S1139.48 (11)C21—C20—C22111.13 (15)
N2—C8—S1109.21 (10)C21—C20—C19111.68 (14)
N3—C9—N2108.36 (13)C22—C20—C19109.77 (16)
N3—C9—C10127.27 (13)C21—C20—H20A108.0
N2—C9—C10124.35 (13)C22—C20—H20A108.0
C9—C10—C11109.88 (13)C19—C20—H20A108.0
C9—C10—C18109.90 (13)C20—C21—H21A109.5
C11—C10—C18113.81 (13)C20—C21—H21B109.5
C9—C10—H10A107.7H21A—C21—H21B109.5
C11—C10—H10A107.7C20—C21—H21C109.5
C18—C10—H10A107.7H21A—C21—H21C109.5
C12—C11—C16117.76 (15)H21B—C21—H21C109.5
C12—C11—C10121.62 (13)C20—C22—H22A109.5
C16—C11—C10120.61 (14)C20—C22—H22B109.5
C13—C12—C11120.99 (14)H22A—C22—H22B109.5
C13—C12—H12A119.5C20—C22—H22C109.5
C11—C12—H12A119.5H22A—C22—H22C109.5
C12—C13—C14121.37 (15)H22B—C22—H22C109.5
C7—N1—N2—C8−1.13 (17)N4—N3—C9—N20.11 (17)
C7—N1—N2—C9177.66 (15)N4—N3—C9—C10−178.01 (14)
C9—N3—N4—C8−0.02 (17)C8—N2—C9—N3−0.16 (16)
C6—C1—C2—C3−1.1 (2)N1—N2—C9—N3−179.05 (14)
C1—C2—C3—C4−0.1 (2)C8—N2—C9—C10178.03 (14)
C1—C2—C3—C17−179.98 (13)N1—N2—C9—C10−0.9 (3)
C2—C3—C4—C50.9 (2)N3—C9—C10—C11108.16 (17)
C17—C3—C4—C5−179.20 (14)N2—C9—C10—C11−69.68 (18)
C3—C4—C5—C6−0.5 (2)N3—C9—C10—C18−17.8 (2)
C4—C5—C6—C1−0.6 (2)N2—C9—C10—C18164.34 (14)
C4—C5—C6—C7179.78 (13)C9—C10—C11—C12−85.94 (17)
C2—C1—C6—C51.4 (2)C18—C10—C11—C1237.8 (2)
C2—C1—C6—C7−178.96 (13)C9—C10—C11—C1693.15 (17)
N2—N1—C7—C6−179.59 (12)C18—C10—C11—C16−143.13 (15)
N2—N1—C7—S11.19 (15)C16—C11—C12—C130.4 (2)
C5—C6—C7—N1176.10 (14)C10—C11—C12—C13179.48 (13)
C1—C6—C7—N1−3.5 (2)C11—C12—C13—C14−1.2 (2)
C5—C6—C7—S1−4.72 (19)C12—C13—C14—C150.6 (2)
C1—C6—C7—S1175.70 (11)C12—C13—C14—C19−179.48 (14)
C8—S1—C7—N1−0.81 (12)C13—C14—C15—C160.7 (2)
C8—S1—C7—C6179.96 (12)C19—C14—C15—C16−179.20 (15)
N3—N4—C8—N2−0.09 (16)C14—C15—C16—C11−1.5 (3)
N3—N4—C8—S1178.05 (14)C12—C11—C16—C150.9 (2)
C9—N2—C8—N40.15 (17)C10—C11—C16—C15−178.18 (14)
N1—N2—C8—N4179.27 (12)C13—C14—C19—C20−122.58 (16)
C9—N2—C8—S1−178.56 (10)C15—C14—C19—C2057.3 (2)
N1—N2—C8—S10.55 (16)C14—C19—C20—C2155.9 (2)
C7—S1—C8—N4−178.04 (19)C14—C19—C20—C22179.58 (14)
C7—S1—C8—N20.12 (11)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5A···S10.932.703.1194 (16)108
C15—H15A···N3i0.932.483.343 (2)155
C4—H4A···Cg1ii0.932.623.5063160
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C5—H5A···S10.932.703.1194 (16)108
C15—H15A···N3i0.932.483.343 (2)155
C4—H4A···Cg1ii0.932.623.5063160
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y, −z+1.
Acknowledgements top

FHK and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. FHK and IAR also thank the Malaysian Government and Universiti Sains Malaysia for the FRGS grant No. 203/PFIZIK/671064. SRJ thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

references
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