2,2′-[2,3,5,6-Tetra­methyl-p-phenyl­ene­bis(methyl­enethio)]bis­(pyridine N-oxide)

Abstract

Mol­ecules of the title compound, C₂₂H₂₄N₂O₂S₂, lie across centres of inversion. The two thio­pyridine N-oxide groups adopt a stepped trans configuration with respect to the benzene ring, by virtue of the symmetry. The oxopyridinium ring forms a dihedral angle of 79.9 (2)° with the benzene ring. The crystal structure is stabilized by a strong π–π inter­action between the pyridinium rings of adjacent mol­ecules [ring centroid–centroid distance = 3.464 (3) Å].

Related literature

For bond-length data, see: Allen et al. (1987 ▶). For biological activities of N-oxide derivatives, see: Bovin et al. (1992 ▶); Katsuyuki et al. (1991 ▶); Leonard et al. (1955 ▶); Lobana & Bhatia (1989 ▶); Symons & West (1985 ▶). For a related structure, see: Hartung et al. (1996 ▶).

Experimental

Crystal data

• C₂₂H₂₄N₂O₂S₂

• M _r = 412.55

• Monoclinic,

• a = 11.8431 (13) Å

• b = 9.0108 (9) Å

• c = 9.7551 (10) Å

• β = 112.611 (9)°

• V = 961.01 (17) ų

• Z = 2

• Cu Kα radiation

• μ = 2.68 mm⁻¹

• T = 193 (2) K

• 0.10 × 0.10 × 0.05 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.80, T _max = 0.87

• 1929 measured reflections

• 1813 independent reflections

• 1200 reflections with I > 2σ(I)

• R _int = 0.077

• 3 standard reflections frequency: 60 min intensity decay: 3%

Refinement

• R[F ² > 2σ(F ²)] = 0.057

• wR(F ²) = 0.170

• S = 0.99

• 1813 reflections

• 129 parameters

• H-atom parameters constrained

• Δρ_max = 0.42 e Å⁻³

• Δρ_min = −0.41 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); 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 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

N-Oxides and their derivatives show a broad spectrum of biological activity, such as antifungal, antibacterial, antimicrobial and antibiotic activities (Lobana & Bhatia, 1989; Symons et al., 1985). These compounds are also found to be involved in DNA strand scission under physiological conditions (Katsuyuki et al., 1991; Bovin et al., 1992). Pyridine N-oxides bearing a sulfur group in position 2 display significant antimicrobial activity (Leonard et al., 1955).

The asymmetric unit of the title compound consists of one half of a centrosymmetric molecule. The two thiopyridine-N-oxide groups adopt a stepped trans conformation with respect to the benzene ring, by virtue of the symmetry. The oxopyridinium ring forms a dihedral angle of 79.9 (2)° with the benzene ring. The N—O bond length is in good agreement with the mean value of 1.304 (15)Å reported in the literature for pyridine N-oxides (Allen et al., 1987). As observed in a similar structure (Hartung et al., 1996), the S atom is bent significantly towards the N-oxide O atom [N9—C8—S7 = 111.4 (3)°].

The crystal packing is stabilized by a strong π-π interaction between the pyridinium rings of adjacent molecules at (x, y, z) and (-x, 2 - y, -z), with a ring centroid to centroid distance of 3.464 (3) Å.

Experimental

A mixture of 1,4-bis(bromomethyl)durene (0.320, 1 mmol) and 1-hydroxypyridine-2-thione sodium salt (0.298,2 mmol) in water (30 ml) and methanol (30 ml) was heated at 333 K with stirring for 30 min. The compound formed was filtered off, and dried (0.34 g, 82%). The compound was recrystallized from chloroform-methanol (1:2 v/v).

Refinement

C-bound H atoms were placed in calculated positions [C—H = 0.95 Å (aromatic), 0.98 Å (methylene), and 0.99 Å (methyl)] and refined in the riding-model approximation, with U_iso(H)=1.2–1.5U_eq(C).

Figures

Fig. 1.

The molecular structure of the title compound, showing 50% probability displacement ellipsoids. Atoms labelled with the suffix a are generated by the symmetry operations (1 - x, 1 - y, 1 - z).

Crystal data

C22H24N2O2S2	F000 = 436
Mr = 412.55	Dx = 1.426 Mg m−3
Monoclinic, P21/c	Cu Kα radiation λ = 1.54178 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 11.8431 (13) Å	θ = 15–29.3º
b = 9.0108 (9) Å	µ = 2.68 mm−1
c = 9.7551 (10) Å	T = 193 (2) K
β = 112.611 (9)º	Block, colourless
V = 961.01 (17) Å3	0.10 × 0.10 × 0.05 mm
Z = 2

Data collection

Enraf–Nonius CAD-4 diffractometer	θmax = 70º
ω/2θ scans	θmin = 4.0º
Absorption correction: ψ scan(North et al., 1968)	h = −14→13
Tmin = 0.80, Tmax = 0.87	k = 0→10
1929 measured reflections	l = 0→11
1813 independent reflections	3 standard reflections
1200 reflections with I > 2σ(I)	every 60 min
Rint = 0.077	intensity decay: 3%

Refinement

Refinement on F2	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ2(Fo2) + (0.1008P)2] where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.057	(Δ/σ)max < 0.001
wR(F2) = 0.170	Δρmax = 0.42 e Å−3
S = 0.99	Δρmin = −0.41 e Å−3
1813 reflections	Extinction correction: none
129 parameters

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.4444 (3)	0.6186 (4)	0.4063 (4)	0.0220 (8)
C2	0.5351 (3)	0.6459 (4)	0.5463 (4)	0.0234 (8)
C3	0.4077 (3)	0.4715 (4)	0.3606 (4)	0.0243 (8)
C4	0.5706 (4)	0.8042 (4)	0.5965 (4)	0.0305 (9)
H4A	0.5049	0.8714	0.5374	0.046*
H4B	0.646	0.8299	0.583	0.046*
H4C	0.5838	0.8136	0.7017	0.046*
C5	0.3044 (4)	0.4452 (4)	0.2124 (4)	0.0347 (10)
H5A	0.2428	0.5233	0.1942	0.052*
H5B	0.267	0.3484	0.2132	0.052*
H5C	0.3365	0.447	0.1336	0.052*
C6	0.3835 (3)	0.7458 (4)	0.3017 (4)	0.0258 (8)
H6A	0.3528	0.7114	0.1973	0.031*
H6B	0.4429	0.827	0.3138	0.031*
S7	0.25697 (9)	0.81142 (11)	0.34802 (10)	0.0290 (3)
C8	0.1962 (3)	0.9526 (4)	0.2167 (4)	0.0254 (8)
N9	0.1042 (3)	1.0262 (4)	0.2392 (4)	0.0293 (7)
C10	0.0488 (4)	1.1435 (4)	0.1524 (5)	0.0340 (10)
H10	−0.0123	1.1969	0.1725	0.041*
C11	0.0792 (4)	1.1863 (4)	0.0363 (5)	0.0347 (9)
H11	0.0394	1.2683	−0.0242	0.042*
C12	0.1688 (4)	1.1083 (5)	0.0083 (5)	0.0358 (10)
H12	0.1889	1.1346	−0.0739	0.043*
C13	0.2287 (4)	0.9925 (4)	0.0998 (4)	0.0287 (9)
H13	0.2918	0.9405	0.0826	0.034*
O14	0.0730 (3)	0.9825 (4)	0.3471 (3)	0.0443 (8)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.032 (2)	0.0160 (17)	0.0218 (18)	0.0012 (15)	0.0144 (16)	0.0009 (14)
C2	0.0280 (19)	0.0172 (17)	0.0262 (19)	−0.0026 (14)	0.0117 (15)	−0.0053 (15)
C3	0.0294 (19)	0.0227 (19)	0.0217 (17)	−0.0043 (15)	0.0106 (15)	−0.0028 (15)
C4	0.038 (2)	0.0189 (19)	0.033 (2)	−0.0065 (17)	0.0124 (18)	−0.0023 (17)
C5	0.044 (2)	0.025 (2)	0.031 (2)	−0.0021 (19)	0.0101 (19)	−0.0028 (18)
C6	0.0303 (19)	0.0221 (17)	0.026 (2)	0.0011 (16)	0.0116 (16)	−0.0001 (16)
S7	0.0373 (5)	0.0247 (5)	0.0282 (5)	0.0039 (4)	0.0160 (4)	0.0041 (4)
C8	0.028 (2)	0.0183 (18)	0.0265 (19)	−0.0018 (15)	0.0065 (16)	−0.0063 (15)
N9	0.0308 (17)	0.0260 (17)	0.0300 (17)	0.0000 (14)	0.0102 (14)	−0.0034 (14)
C10	0.030 (2)	0.025 (2)	0.038 (2)	0.0035 (16)	0.0031 (18)	−0.0069 (18)
C11	0.035 (2)	0.0224 (19)	0.037 (2)	−0.0048 (18)	0.0027 (17)	−0.0011 (19)
C12	0.039 (2)	0.031 (2)	0.034 (2)	−0.0059 (18)	0.0102 (18)	0.0004 (18)
C13	0.035 (2)	0.0233 (19)	0.0249 (19)	−0.0011 (16)	0.0086 (17)	0.0008 (16)
O14	0.055 (2)	0.0477 (19)	0.0421 (18)	0.0125 (16)	0.0316 (16)	0.0064 (15)

Geometric parameters (Å, °)

C1—C2	1.398 (5)	C11—C12	1.384 (6)
C1—C3	1.412 (5)	C12—C13	1.379 (6)
C1—C6	1.520 (5)	C4—H4A	0.98
C2—C3i	1.389 (5)	C4—H4B	0.98
C2—C4	1.514 (5)	C4—H4C	0.98
C3—C2i	1.389 (5)	C5—H5A	0.98
C3—C5	1.511 (5)	C5—H5B	0.98
C6—S7	1.822 (4)	C5—H5C	0.98
S7—C8	1.752 (4)	C6—H6A	0.99
C8—N9	1.364 (5)	C6—H6B	0.99
C8—C13	1.384 (5)	C10—H10	0.95
N9—O14	1.303 (4)	C11—H11	0.95
N9—C10	1.355 (5)	C12—H12	0.95
C10—C11	1.369 (6)	C13—H13	0.95
C2—C1—C3	120.1 (3)	C2—C4—H4C	109
C2—C1—C6	120.8 (3)	H4A—C4—H4B	109
C3—C1—C6	119.2 (3)	H4A—C4—H4C	109
C3i—C2—C1	120.2 (3)	H4B—C4—H4C	109
C3i—C2—C4	120.1 (3)	C3—C5—H5A	109
C1—C2—C4	119.7 (3)	C3—C5—H5B	110
C2i—C3—C1	119.7 (3)	C3—C5—H5C	109
C2i—C3—C5	121.2 (3)	H5A—C5—H5B	109
C1—C3—C5	119.1 (3)	H5A—C5—H5C	109
C1—C6—S7	107.5 (2)	H5B—C5—H5C	110
C8—S7—C6	101.51 (18)	S7—C6—H6A	110
N9—C8—C13	119.9 (4)	S7—C6—H6B	110
N9—C8—S7	111.4 (3)	C1—C6—H6A	110
C13—C8—S7	128.7 (3)	C1—C6—H6B	110
O14—N9—C10	121.4 (4)	H6A—C6—H6B	108
O14—N9—C8	118.4 (3)	N9—C10—H10	119
C10—N9—C8	120.2 (4)	C11—C10—H10	119
N9—C10—C11	121.2 (4)	C10—C11—H11	120
C10—C11—C12	119.1 (4)	C12—C11—H11	120
C13—C12—C11	119.9 (4)	C11—C12—H12	120
C12—C13—C8	119.6 (4)	C13—C12—H12	120
C2—C4—H4A	109	C8—C13—H13	120
C2—C4—H4B	109	C12—C13—H13	120
C3—C1—C2—C3i	2.0 (6)	C6—S7—C8—C13	5.8 (4)
C6—C1—C2—C3i	−178.3 (3)	C13—C8—N9—O14	177.6 (3)
C3—C1—C2—C4	−177.7 (3)	S7—C8—N9—O14	−1.6 (4)
C6—C1—C2—C4	1.9 (5)	C13—C8—N9—C10	−3.5 (5)
C2—C1—C3—C2i	−2.0 (6)	S7—C8—N9—C10	177.3 (3)
C6—C1—C3—C2i	178.3 (3)	O14—N9—C10—C11	−177.9 (4)
C2—C1—C3—C5	176.5 (3)	C8—N9—C10—C11	3.2 (6)
C6—C1—C3—C5	−3.1 (5)	N9—C10—C11—C12	−0.4 (6)
C2—C1—C6—S7	−86.0 (4)	C10—C11—C12—C13	−2.1 (6)
C3—C1—C6—S7	93.6 (4)	C11—C12—C13—C8	1.8 (6)
C1—C6—S7—C8	−178.8 (2)	N9—C8—C13—C12	1.0 (6)
C6—S7—C8—N9	−175.2 (3)	S7—C8—C13—C12	−180.0 (3)

Symmetry codes: (i) −x+1, −y+1, −z+1.