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Acta Cryst. (2010). E66, o2178-o2179    [ doi:10.1107/S1600536810029910 ]

4-[3-(Phenoxymethyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-3-(p-tolyl)sydnone

J. H. Goh, H.-K. Fun, Nithinchandra and B. Kalluraya

Abstract top

In the title triazolothiadiazine derivative, C20H16N6O3S {systematic name: 3-(4-methylphenyl)-4-[3-(phenoxymethyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-1,2,3-oxadiazol-3-ium-5-olate}, an S(6) ring motif is generated by an intramolecular C-H...O hydrogen bond. The 3,6-dihydro-1,3,4-thiadiazine ring adopts a twist-boat conformation. The dihedral angle between the 1,2,3-oxadiazole and 1,2,4-triazole rings is 46.45 (14)°. The 1,2,3-oxadiazole ring is inclined at dihedral angle of 59.49 (13)° with respect to the benzene ring attached to it. In the crystal structure, intermolecular C-H...O and C-H...N hydrogen bonds link neighbouring molecules into two-molecule-thick arrays parallel to the bc plane. A short S...O interaction [2.9565 (19) Å] also occurs.

Comment top

Sydnones are a novel class of mesoionic compounds consisting of 1,2,3-oxadiazole ring system. A number of sydnone derivatives have shown diverse biological activities such as anti-inflammatory, analgesic and anti-arthritic (Newton & Ramsden, 1982; Wagner & Hill, 1974) properties. Sydnones possessing heterocyclic moieties at the 4-position are also known for a wide range of biological properties (Kalluraya & Rahiman, 1997). Encouraged by these reports and in continuation of our research for biologically active nitrogen containing heterocycles, a triazolothiadiazine moiety at the 4-position of the phenylsydnone was introduced.

In the title triazolothiadiazine derivative, an intramolecular C10—H10A···O3 hydrogen bond (Table 1) generates a six-membered ring, producing an S(6) hydrogen bond ring motif (Fig. 1, Bernstein et al., 1995). The 3,6-dihydro-1,3,4-thiadiazine ring (C9-C11/N3/N4/S1) adopts twist-boat conformation, with puckering parameters of Q = 0.634 (2) Å, θ = 67.08 (18)° and φ = 322.1 (2)° (Cremer & Pople, 1975). The dihedral angle formed between these essentially planar 1,2,3-oxadiazole (C12/C13/O2/N5/N6) and 1,2,4-triazole (C8/N1/N2/C9/N3) rings is 46.45 (14)°. The C1-C6 and C14-C19 phenyl rings are inclined at dihedral angles of 77.56 (14) and 59.49 (13)°, respectively, with respect to 1,2,3-oxadiazole and 1,2,4-triazole rings. The geometric parameters are consistent to those observed in closely related structures (Goh et al., 2010a,b,c).

In the crystal structure, intermolecular C10—H10A···O3, C10—H10B···O3 and C19—H19A···N5 hydrogen bonds (Table 1) interconnect neighbouring molecules into two-molecule-thick arrays parallel to the bc plane (Fig. 2). The interesting feature of the crystal structure is the intermolecular short S1···O3 interaction [2.9565 (19) Å; symmetry code: -x, -y, -z+1], which is significantly shorter than the sum of Van der Waals radii of the relevant atoms, further stabilizing the crystal structure.

Related literature top

For general background to and applications of materials related to the title compound, see: Kalluraya & Rahiman (1997); Newton & Ramsden (1982); Wagner & Hill (1974). For graph-set descriptions of hydrogen-bond ring motifs, see: Bernstein et al. (1995). For closely related structures, see: Goh et al. (2010a,b,c). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

A solution of triazole (0.01 mol) and 4-bromoacetyl-3-tolylsydnone (0.01 mol) in absolute ethanol (20 ml) was heated under reflux for 10–12 h. The solution was concentrated, cooled to room temperature and neutrallized with 10 % sodium bicarbonate solution. The solid separated was filtered, washed with water, dried and recrystallized from ethanol. Colourless blocks of (I) were obtained from a 1:2 mixture of DMF and ethanol by slow evaporation.

Refinement top

All hydrogen atoms were placed in their calculated positions, with C—H = 0.93–0.97 Å, and refined using a riding model, with Uiso = 1.2 or 1.5 Ueq(C). The rotating group model was used for the methyl group.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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 (I), showing 50% probability displacement ellipsoids for non-H atoms. An intramolecular hydrogen bond is shown as dashed line.
[Figure 2] Fig. 2. The crystal structure of (I), viewed along the b axis, showing two-molecule-thick arrays parallel to the bc plane. Hydrogen atoms not involved in intermolecular interactions (dashed lines) have been omitted for clarity.
3-(4-methylphenyl)-4-[3-(phenoxymethyl)-7H-1,2,4- triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-1,2,3-oxadiazol-3-ium-5-olate top
Crystal data top
C20H16N6O3SF(000) = 872
Mr = 420.45Dx = 1.482 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4257 reflections
a = 20.6555 (7) Åθ = 2.7–30.6°
b = 8.1918 (3) ŵ = 0.21 mm−1
c = 11.1979 (4) ÅT = 100 K
β = 96.127 (2)°Block, colourless
V = 1883.93 (12) Å30.26 × 0.13 × 0.07 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD
diffractometer		4318 independent reflections
Radiation source: fine-focus sealed tube2829 reflections with I > 2σ(I)
graphiteRint = 0.065
φ and ω scansθmax = 27.5°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		h = −26→26
Tmin = 0.947, Tmax = 0.985k = −10→10
17653 measured reflectionsl = −14→14
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)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.133H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.060P)2 + 0.4167P]
where P = (Fo2 + 2Fc2)/3
4318 reflections(Δ/σ)max = 0.003
272 parametersΔρmax = 0.67 e Å−3
0 restraintsΔρmin = −0.53 e Å−3
Crystal data top
C20H16N6O3SV = 1883.93 (12) Å3
Mr = 420.45Z = 4
Monoclinic, P21/cMo Kα radiation
a = 20.6555 (7) ŵ = 0.21 mm−1
b = 8.1918 (3) ÅT = 100 K
c = 11.1979 (4) Å0.26 × 0.13 × 0.07 mm
β = 96.127 (2)°
Data collection top
Bruker SMART APEXII CCD
diffractometer		4318 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		2829 reflections with I > 2σ(I)
Tmin = 0.947, Tmax = 0.985Rint = 0.065
17653 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.060H-atom parameters constrained
wR(F2) = 0.133Δρmax = 0.67 e Å−3
S = 1.03Δρmin = −0.53 e Å−3
4318 reflectionsAbsolute structure: ?
272 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
S10.06014 (3)0.33229 (8)0.37690 (6)0.01451 (18)
O10.28045 (8)0.2544 (2)0.08679 (15)0.0183 (5)
O20.10735 (9)−0.3314 (2)0.48621 (15)0.0174 (4)
O30.01271 (9)−0.1961 (2)0.43267 (15)0.0168 (4)
N10.16326 (10)0.4933 (3)0.13016 (18)0.0159 (5)
N20.12096 (10)0.5222 (3)0.21876 (19)0.0159 (5)
N30.14032 (10)0.2588 (3)0.20962 (18)0.0119 (5)
N40.15133 (10)0.0982 (3)0.24765 (18)0.0134 (5)
N50.17122 (11)−0.3211 (3)0.46629 (19)0.0167 (5)
N60.17491 (10)−0.1933 (3)0.39705 (18)0.0130 (5)
C10.38786 (14)0.2084 (4)0.0490 (2)0.0226 (7)
H1A0.40120.26240.12040.027*
C20.43384 (14)0.1464 (4)−0.0207 (3)0.0282 (8)
H2A0.47790.16020.00400.034*
C30.41449 (14)0.0641 (4)−0.1269 (3)0.0263 (7)
H3A0.44530.0212−0.17300.032*
C40.34920 (14)0.0469 (4)−0.1629 (3)0.0235 (7)
H4A0.3361−0.0070−0.23450.028*
C50.30230 (14)0.1081 (4)−0.0949 (2)0.0194 (7)
H5A0.25830.0949−0.12020.023*
C60.32231 (13)0.1897 (3)0.0121 (2)0.0168 (6)
C70.21295 (12)0.2477 (3)0.0432 (2)0.0149 (6)
H7A0.19880.13480.03630.018*
H7B0.20600.2974−0.03570.018*
C80.17459 (12)0.3361 (3)0.1279 (2)0.0142 (6)
C90.10811 (12)0.3793 (3)0.2631 (2)0.0123 (6)
C100.04330 (12)0.1268 (3)0.3200 (2)0.0148 (6)
H10A0.01850.06740.37460.018*
H10B0.01750.13230.24240.018*
C110.10610 (12)0.0393 (3)0.3078 (2)0.0125 (6)
C120.11699 (12)−0.1155 (3)0.3677 (2)0.0123 (6)
C130.07074 (14)−0.2057 (3)0.4260 (2)0.0143 (6)
C140.24014 (12)−0.1537 (3)0.3708 (2)0.0137 (6)
C150.28634 (13)−0.1262 (3)0.4668 (2)0.0182 (6)
H15A0.2749−0.12660.54490.022*
C160.35008 (14)−0.0980 (4)0.4450 (3)0.0228 (7)
H16A0.3817−0.07980.50920.027*
C170.36760 (14)−0.0964 (4)0.3281 (3)0.0213 (7)
C180.31939 (13)−0.1232 (3)0.2334 (2)0.0206 (7)
H18A0.3305−0.12090.15510.025*
C190.25567 (13)−0.1529 (3)0.2528 (2)0.0178 (6)
H19A0.2240−0.17180.18890.021*
C200.43702 (14)−0.0674 (4)0.3043 (3)0.0351 (8)
H20D0.4422−0.09660.22290.053*
H20A0.4655−0.13300.35810.053*
H20B0.44760.04580.31690.053*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0213 (4)0.0098 (4)0.0135 (3)0.0003 (3)0.0064 (2)0.0003 (3)
O10.0180 (10)0.0225 (12)0.0146 (9)0.0027 (9)0.0028 (7)−0.0026 (9)
O20.0265 (11)0.0118 (11)0.0144 (9)0.0002 (9)0.0041 (8)0.0034 (9)
O30.0196 (10)0.0162 (11)0.0150 (9)−0.0027 (9)0.0040 (7)0.0016 (9)
N10.0233 (13)0.0158 (14)0.0094 (10)−0.0014 (11)0.0052 (9)0.0023 (11)
N20.0229 (13)0.0122 (13)0.0130 (11)0.0001 (11)0.0039 (9)0.0019 (11)
N30.0174 (12)0.0089 (12)0.0105 (10)−0.0002 (10)0.0059 (9)0.0032 (10)
N40.0242 (13)0.0075 (12)0.0084 (10)0.0003 (10)0.0017 (9)0.0002 (10)
N50.0247 (13)0.0109 (13)0.0148 (11)−0.0014 (11)0.0039 (9)−0.0016 (11)
N60.0238 (12)0.0072 (12)0.0079 (10)−0.0003 (10)0.0015 (9)−0.0003 (10)
C10.0280 (16)0.0200 (17)0.0193 (14)0.0012 (14)0.0003 (12)−0.0037 (14)
C20.0205 (16)0.030 (2)0.0342 (17)0.0029 (14)0.0025 (13)0.0007 (17)
C30.0305 (18)0.0229 (18)0.0278 (16)0.0045 (15)0.0143 (13)0.0008 (15)
C40.0322 (17)0.0199 (17)0.0193 (14)0.0023 (15)0.0079 (12)−0.0012 (14)
C50.0237 (15)0.0181 (17)0.0169 (14)−0.0030 (13)0.0040 (11)0.0005 (14)
C60.0217 (15)0.0133 (16)0.0161 (13)0.0035 (13)0.0058 (11)0.0055 (13)
C70.0207 (14)0.0135 (16)0.0109 (12)0.0000 (12)0.0039 (10)0.0030 (12)
C80.0195 (14)0.0126 (15)0.0107 (12)−0.0032 (13)0.0015 (10)0.0031 (13)
C90.0167 (14)0.0087 (15)0.0117 (12)−0.0004 (12)0.0020 (10)−0.0001 (12)
C100.0205 (14)0.0086 (15)0.0156 (13)−0.0019 (12)0.0025 (11)0.0021 (12)
C110.0177 (14)0.0122 (15)0.0074 (12)−0.0003 (12)0.0009 (10)−0.0039 (12)
C120.0164 (14)0.0105 (15)0.0103 (12)0.0006 (12)0.0028 (10)−0.0036 (12)
C130.0304 (16)0.0058 (15)0.0070 (12)0.0004 (13)0.0035 (11)−0.0005 (12)
C140.0172 (14)0.0087 (15)0.0154 (13)0.0023 (12)0.0023 (10)−0.0015 (13)
C150.0287 (16)0.0152 (16)0.0111 (12)0.0022 (13)0.0040 (11)0.0014 (13)
C160.0243 (16)0.0198 (17)0.0236 (15)0.0013 (14)−0.0002 (12)−0.0005 (15)
C170.0239 (16)0.0148 (16)0.0265 (16)0.0010 (13)0.0083 (12)0.0040 (14)
C180.0293 (16)0.0177 (17)0.0164 (13)0.0048 (14)0.0097 (12)0.0033 (13)
C190.0291 (16)0.0108 (16)0.0134 (13)0.0039 (13)0.0023 (11)0.0005 (13)
C200.0268 (17)0.043 (2)0.0368 (19)−0.0018 (17)0.0080 (14)0.0098 (18)
Geometric parameters (Å, °) top
S1—C91.739 (3)C4—H4A0.9300
S1—C101.820 (3)C5—C61.395 (4)
O1—C61.372 (3)C5—H5A0.9300
O1—C71.428 (3)C7—C81.487 (4)
O2—N51.364 (3)C7—H7A0.9700
O2—C131.406 (3)C7—H7B0.9700
O3—C131.212 (3)C10—C111.501 (4)
N1—C81.310 (3)C10—H10A0.9700
N1—N21.410 (3)C10—H10B0.9700
N2—C91.310 (3)C11—C121.441 (4)
N3—C91.364 (3)C12—C131.420 (4)
N3—C81.371 (3)C14—C151.378 (4)
N3—N41.395 (3)C14—C191.393 (3)
N4—C111.301 (3)C15—C161.384 (4)
N5—N61.310 (3)C15—H15A0.9300
N6—C121.364 (3)C16—C171.395 (4)
N6—C141.446 (3)C16—H16A0.9300
C1—C61.381 (4)C17—C181.392 (4)
C1—C21.388 (4)C17—C201.505 (4)
C1—H1A0.9300C18—C191.378 (4)
C2—C31.389 (4)C18—H18A0.9300
C2—H2A0.9300C19—H19A0.9300
C3—C41.373 (4)C20—H20D0.9600
C3—H3A0.9300C20—H20A0.9600
C4—C51.389 (4)C20—H20B0.9600
C9—S1—C1092.89 (12)N2—C9—S1129.0 (2)
C6—O1—C7115.64 (19)N3—C9—S1120.3 (2)
N5—O2—C13110.89 (19)C11—C10—S1109.82 (18)
C8—N1—N2107.7 (2)C11—C10—H10A109.7
C9—N2—N1106.4 (2)S1—C10—H10A109.7
C9—N3—C8105.7 (2)C11—C10—H10B109.7
C9—N3—N4128.3 (2)S1—C10—H10B109.7
C8—N3—N4124.1 (2)H10A—C10—H10B108.2
C11—N4—N3113.9 (2)N4—C11—C12118.8 (2)
N6—N5—O2105.33 (19)N4—C11—C10123.0 (2)
N5—N6—C12114.3 (2)C12—C11—C10118.1 (2)
N5—N6—C14114.4 (2)N6—C12—C13105.2 (2)
C12—N6—C14131.2 (2)N6—C12—C11127.8 (2)
C6—C1—C2120.0 (3)C13—C12—C11126.3 (2)
C6—C1—H1A120.0O3—C13—O2120.2 (2)
C2—C1—H1A120.0O3—C13—C12135.5 (3)
C1—C2—C3120.5 (3)O2—C13—C12104.3 (2)
C1—C2—H2A119.8C15—C14—C19121.9 (2)
C3—C2—H2A119.8C15—C14—N6117.5 (2)
C4—C3—C2119.0 (3)C19—C14—N6120.5 (2)
C4—C3—H3A120.5C14—C15—C16118.8 (2)
C2—C3—H3A120.5C14—C15—H15A120.6
C3—C4—C5121.5 (3)C16—C15—H15A120.6
C3—C4—H4A119.2C15—C16—C17120.9 (3)
C5—C4—H4A119.2C15—C16—H16A119.5
C4—C5—C6119.0 (3)C17—C16—H16A119.5
C4—C5—H5A120.5C18—C17—C16118.5 (3)
C6—C5—H5A120.5C18—C17—C20120.6 (3)
O1—C6—C1115.9 (2)C16—C17—C20121.0 (3)
O1—C6—C5124.1 (2)C19—C18—C17121.7 (2)
C1—C6—C5120.0 (3)C19—C18—H18A119.1
O1—C7—C8109.3 (2)C17—C18—H18A119.1
O1—C7—H7A109.8C18—C19—C14118.1 (2)
C8—C7—H7A109.8C18—C19—H19A121.0
O1—C7—H7B109.8C14—C19—H19A121.0
C8—C7—H7B109.8C17—C20—H20D109.5
H7A—C7—H7B108.3C17—C20—H20A109.5
N1—C8—N3109.6 (2)H20D—C20—H20A109.5
N1—C8—C7126.9 (2)C17—C20—H20B109.5
N3—C8—C7123.3 (2)H20D—C20—H20B109.5
N2—C9—N3110.6 (2)H20A—C20—H20B109.5
C8—N1—N2—C9−1.4 (3)C9—S1—C10—C1154.65 (19)
C9—N3—N4—C1130.0 (3)N3—N4—C11—C12−170.4 (2)
C8—N3—N4—C11−167.9 (2)N3—N4—C11—C108.3 (3)
C13—O2—N5—N60.5 (2)S1—C10—C11—N4−53.7 (3)
O2—N5—N6—C12−0.3 (3)S1—C10—C11—C12125.0 (2)
O2—N5—N6—C14176.24 (18)N5—N6—C12—C130.1 (3)
C6—C1—C2—C3−0.6 (5)C14—N6—C12—C13−175.8 (2)
C1—C2—C3—C40.9 (5)N5—N6—C12—C11170.7 (2)
C2—C3—C4—C5−0.8 (4)C14—N6—C12—C11−5.2 (4)
C3—C4—C5—C60.4 (4)N4—C11—C12—N618.5 (4)
C7—O1—C6—C1174.7 (2)C10—C11—C12—N6−160.3 (2)
C7—O1—C6—C5−5.8 (4)N4—C11—C12—C13−172.8 (2)
C2—C1—C6—O1179.8 (3)C10—C11—C12—C138.4 (4)
C2—C1—C6—C50.2 (4)N5—O2—C13—O3179.4 (2)
C4—C5—C6—O1−179.7 (3)N5—O2—C13—C12−0.4 (2)
C4—C5—C6—C1−0.1 (4)N6—C12—C13—O3−179.6 (3)
C6—O1—C7—C8−174.6 (2)C11—C12—C13—O39.6 (5)
N2—N1—C8—N31.3 (3)N6—C12—C13—O20.2 (3)
N2—N1—C8—C7175.7 (2)C11—C12—C13—O2−170.6 (2)
C9—N3—C8—N1−0.8 (3)N5—N6—C14—C15−56.8 (3)
N4—N3—C8—N1−166.3 (2)C12—N6—C14—C15119.1 (3)
C9—N3—C8—C7−175.4 (2)N5—N6—C14—C19119.8 (3)
N4—N3—C8—C719.1 (4)C12—N6—C14—C19−64.4 (4)
O1—C7—C8—N184.4 (3)C19—C14—C15—C16−0.4 (4)
O1—C7—C8—N3−101.9 (3)N6—C14—C15—C16176.1 (2)
N1—N2—C9—N30.8 (3)C14—C15—C16—C170.3 (4)
N1—N2—C9—S1178.78 (18)C15—C16—C17—C180.3 (4)
C8—N3—C9—N2−0.1 (3)C15—C16—C17—C20−179.4 (3)
N4—N3—C9—N2164.6 (2)C16—C17—C18—C19−0.9 (4)
C8—N3—C9—S1−178.20 (18)C20—C17—C18—C19178.8 (3)
N4—N3—C9—S1−13.6 (3)C17—C18—C19—C140.8 (4)
C10—S1—C9—N2154.7 (2)C15—C14—C19—C18−0.1 (4)
C10—S1—C9—N3−27.6 (2)N6—C14—C19—C18−176.5 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O30.972.263.026 (3)135
C10—H10A···O3i0.972.553.165 (3)122
C10—H10B···O3ii0.972.443.279 (3)145
C19—H19A···N5iii0.932.613.491 (3)158
Symmetry codes: (i) −x, −y, −z+1; (ii) −x, y+1/2, −z+1/2; (iii) x, −y−1/2, z−1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C10—H10A···O30.972.263.026 (3)135
C10—H10A···O3i0.972.553.165 (3)122
C10—H10B···O3ii0.972.443.279 (3)145
C19—H19A···N5iii0.932.613.491 (3)158
Symmetry codes: (i) −x, −y, −z+1; (ii) −x, y+1/2, −z+1/2; (iii) x, −y−1/2, z−1/2.
Acknowledgements top

The authors thank Universiti Sains Malaysia (USM) for the Research University Golden Goose grant (No. 1001/PFIZIK/811012). JHG also thanks USM for the award of a USM fellowship.

references
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