Crystal structure of 1-methyl-4-methyl­sulfanyl-1H-pyrazolo­[3,4-d]pyrimidine

Abstract

In the title compound, C₇H₈N₄S, the non-H atoms of the pyrazolo­[3,4-d]pyrimidine ring system and the methyl­sulfanyl group lie on a crystallographic mirror plane. In the crystal, mol­ecules are linked via a number of π–π inter­actions [centroid–centroid distances vary from 3.452 (7) to 3.6062 (8) Å], forming a three-dimensional structure.

Related literature  

For similar compounds, see: El Fal et al. (2013 ▶, 2014a ▶,b ▶); Ouzidan et al. (2011 ▶). For pharmacological and biochemical properties of pyrazolo­[3,4-d]pyrimidine-4(5H)-thione derivatives, see: Chauhan & Kumar (2013 ▶); Venkatesan et al. (2014 ▶); Rashad et al. (2011 ▶).

Experimental  

Crystal data  

• C₇H₈N₄S

• M _r = 180.23

• Orthorhombic,

• a = 7.9309 (14) Å

• b = 15.335 (3) Å

• c = 6.7158 (12) Å

• V = 816.8 (3) ų

• Z = 4

• Mo Kα radiation

• μ = 0.34 mm⁻¹

• T = 296 K

• 0.37 × 0.28 × 0.19 mm

Data collection  

• Bruker X8 APEX diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.637, T _max = 0.746

• 2970 measured reflections

• 1227 independent reflections

• 1017 reflections with I > 2σ(I)

• R _int = 0.017

Refinement  

• R[F ² > 2σ(F ²)] = 0.042

• wR(F ²) = 0.129

• S = 1.09

• 1227 reflections

• 73 parameters

• H-atom parameters constrained

• Δρ_max = 0.44 e Å⁻³

• Δρ_min = −0.29 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; 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 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶) and publCIF (Westrip, 2010 ▶).

Supplementary Material

CCDC reference: 1034638

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

S1. Structural commentary

Synthesis of 1H-pyrazolo [3,4-d] pyrimidine-4-thiol derivatives has received considerable attention due to their biological activity especially as anti­microbial (Chauhan et al., 2013), anti­tubercular (Venkatesan et al., 2014) and anti­cancer (Rashad et al., 2011) agents. During the search for new anti­bacterial agents synthesis, some 1H-pyrazolo­[3,4-d] pyrimidine-4-thiol derivatives were prepared (El Fal et al., 2013, 2014a, 2014b; Ouzidan et al., 2011). These compounds are currently under investigation for possible biological activity.

The molecule of the title compound is build up from two fused five- and six-membered rings linked to methyl­sulfanyl group. All non hydrogen atoms of the molecule are coplanar as shown in Fig. 1. In the crystal, the molecules are linked together by a number of π–π inter­actions [centroid–centroid distances vary from 3.452 (7) to 3.6062 (8) Å], forming a three-dimensional structure.

S2. Synthesis and crystallization

To a solution of 1H-pyrazolo [3,4-d] pyrimidine-4-thiol (0.5 g, 3.28 mmol) dissolved in DMF (20 ml) was added iodo­methane (0.43 ml, 6.62 mmol), potassium carbonate (0.93 g, 7.1 mmol) and a catalytic amount of tetra-n-butyl­ammonium bromide (0.1 g, 0.4 mmol). The mixture was stirred for 48 h and monitored by thin layer chromatography. The mixture was filtered and the solvent was removed in vacuo. The solid obtained was crystallized from ethanol to give the title compound as orange crystals (yield: 65%).

S3. Refinement

The H atoms were located in a difference map and treated as riding with C—H = 0.93 Å (aromatic) and C—H = 0.96 Å (methyl), and with U_iso(H) = 1.2 U_eq (aromatic) and U_iso(H) = 1.5 U_eq (methyl).

Figures

Fig. 1.

Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.

Crystal data

C7H8N4S	F(000) = 376
Mr = 180.23	Dx = 1.466 Mg m−3
Orthorhombic, Pbcm	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2c 2b	Cell parameters from 1227 reflections
a = 7.9309 (14) Å	θ = 2.6–29.6°
b = 15.335 (3) Å	µ = 0.34 mm−1
c = 6.7158 (12) Å	T = 296 K
V = 816.8 (3) Å3	Block, orange
Z = 4	0.37 × 0.28 × 0.19 mm

Data collection

Bruker X8 APEX diffractometer	1227 independent reflections
Radiation source: fine-focus sealed tube	1017 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.017
φ and ω scans	θmax = 29.6°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −10→4
Tmin = 0.637, Tmax = 0.746	k = −21→19
2970 measured reflections	l = −3→9

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.129	H-atom parameters constrained
S = 1.09	w = 1/[σ2(Fo2) + (0.0694P)2 + 0.3181P] where P = (Fo2 + 2Fc2)/3
1227 reflections	(Δ/σ)max < 0.001
73 parameters	Δρmax = 0.44 e Å−3
0 restraints	Δρmin = −0.29 e Å−3

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.

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	0.5519 (3)	0.06804 (13)	0.2500	0.0393 (5)
H1	0.4928	0.0156	0.2500	0.047*
C2	0.5516 (3)	0.21199 (12)	0.2500	0.0279 (4)
C3	0.7675 (3)	0.30515 (13)	0.2500	0.0322 (4)
H3	0.8763	0.3277	0.2500	0.039*
C4	0.7284 (2)	0.21512 (11)	0.2500	0.0264 (4)
C5	0.8115 (3)	0.13396 (11)	0.2500	0.0285 (4)
C6	0.3247 (3)	0.32714 (15)	0.2500	0.0450 (6)
H6A	0.3121	0.3658	0.1386	0.068*
H6B	0.2414	0.2818	0.2500	0.068*
C7	1.0858 (3)	0.02097 (16)	0.2500	0.0483 (6)
H7A	0.9865	−0.0148	0.2500	0.072*
H7B	1.1499	0.0095	0.1316	0.072*
N1	0.7221 (2)	0.06053 (10)	0.2500	0.0348 (4)
N2	0.4577 (2)	0.13910 (11)	0.2500	0.0369 (4)
N3	0.4970 (2)	0.29563 (11)	0.2500	0.0323 (4)
N4	0.6289 (3)	0.35277 (10)	0.2500	0.0349 (4)
S1	1.03110 (7)	0.13414 (4)	0.2500	0.0447 (2)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0316 (10)	0.0218 (9)	0.0644 (15)	−0.0024 (7)	0.000	0.000
C2	0.0294 (9)	0.0221 (8)	0.0321 (9)	0.0016 (7)	0.000	0.000
C3	0.0301 (10)	0.0230 (8)	0.0434 (11)	−0.0032 (7)	0.000	0.000
C4	0.0280 (9)	0.0216 (8)	0.0295 (9)	−0.0008 (6)	0.000	0.000
C5	0.0295 (9)	0.0232 (9)	0.0329 (9)	0.0005 (7)	0.000	0.000
C6	0.0329 (11)	0.0330 (11)	0.0692 (16)	0.0095 (9)	0.000	0.000
C7	0.0376 (12)	0.0393 (12)	0.0680 (17)	0.0119 (10)	0.000	0.000
N1	0.0307 (9)	0.0199 (7)	0.0536 (11)	0.0005 (6)	0.000	0.000
N2	0.0290 (9)	0.0250 (9)	0.0568 (12)	−0.0015 (6)	0.000	0.000
N3	0.0318 (8)	0.0221 (7)	0.0429 (9)	0.0024 (6)	0.000	0.000
N4	0.0399 (10)	0.0211 (7)	0.0439 (10)	−0.0021 (6)	0.000	0.000
S1	0.0264 (3)	0.0316 (3)	0.0761 (5)	0.00110 (18)	0.000	0.000

Geometric parameters (Å, º)

C1—N2	1.321 (3)	C5—N1	1.331 (2)
C1—N1	1.355 (3)	C5—S1	1.741 (2)
C1—H1	0.9300	C6—N3	1.449 (3)
C2—N2	1.343 (3)	C6—H6A	0.9598
C2—N3	1.354 (2)	C6—H6B	0.9599
C2—C4	1.403 (3)	C7—S1	1.789 (3)
C3—N4	1.319 (3)	C7—H7A	0.9600
C3—C4	1.415 (2)	C7—H7B	0.9599
C3—H3	0.9300	N3—N4	1.365 (3)
C4—C5	1.408 (2)
N2—C1—N1	129.3 (2)	C4—C5—S1	117.82 (14)
N2—C1—H1	115.3	N3—C6—H6A	107.7
N1—C1—H1	115.3	N3—C6—H6B	114.1
N2—C2—N3	127.68 (18)	H6A—C6—H6B	112.1
N2—C2—C4	125.63 (18)	S1—C7—H7A	110.8
N3—C2—C4	106.69 (17)	S1—C7—H7B	107.8
N4—C3—C4	110.97 (17)	H7A—C7—H7B	109.3
N4—C3—H3	124.5	C5—N1—C1	117.33 (17)
C4—C3—H3	124.5	C1—N2—C2	111.89 (18)
C2—C4—C5	115.96 (17)	C2—N3—N4	111.29 (17)
C2—C4—C3	104.60 (16)	C2—N3—C6	128.13 (19)
C5—C4—C3	139.45 (19)	N4—N3—C6	120.59 (17)
N1—C5—C4	119.88 (19)	C3—N4—N3	106.45 (16)
N1—C5—S1	122.30 (14)	C5—S1—C7	103.95 (11)