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Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): o552–o553.
Published online 2010 February 6. doi:  10.1107/S1600536810004101
PMCID: PMC2983712

9-Furfuryl­idene-2,3-dimethyl-6,7,8,9-tetrahydro-4H-­thieno[2′,3′:4,5]pyrimidino[1,2-a]pyridin-4-one

Abstract

The title compound, C17H16N2O2S, was obtained by condensation of 2,3-dimethyl­thieno[2′,3′:4,5]pyrimidino[1,2-a]pyridin-4-one with furfural in the presence of sodium hydroxide. One of the methyl­ene groups of the tetra­hydro­pyrido ring is disordered over two positions in a 0.87 (1):0.13 (1) ratio. The thieno[2,3-d]pyrimidin-4-one unit and the furan ring are both planar (r.m.s. deviation = 0.535 Å), and coplanar with each other, forming a dihedral angle of 5.4 (1)°. Four weak inter­molecular hydrogen bonds (C—H(...)O and C—H(...)N) are observed in the structure, which join mol­ecules into a network parallel to (101).

Related literature

For the synthesis of thieno[2,3-d]pyrimidin-4-ones and their derivatives, see: Melik-Ogandzhanyan et al. (1985 [triangle]); Csukonyi et al. (1986 [triangle]); Shvedov et al. (1975 [triangle]); Shakhidoyatov (1983 [triangle]); Gevald et al. (1966 [triangle]); Kapustina et al. (1992 [triangle]); Peet et al. (1986 [triangle]); Shodiyev et al. (1993 [triangle]); Bozorov et al. (2009 [triangle]). For the physiological activity of thieno[2,3-d]pyrimidin-4-ones and their derivatives, see: Kapustina et al. (1992 [triangle]); Blaskiewich et al. (1975 [triangle]); Wähäla et al. (2005 [triangle]); Lilienkampf et al. (2007 [triangle]); Han et al. (2007 [triangle]); Moore et al. (2006 [triangle]). For weak hydrogen bonds in alkaloids, see: Rajnikant et al. (2005 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o552-scheme1.jpg

Experimental

Crystal data

  • C17H16N2O2S
  • M r = 312.39
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o552-efi1.jpg
  • a = 16.569 (3) Å
  • b = 11.034 (2) Å
  • c = 8.2775 (17) Å
  • β = 93.12 (3)°
  • V = 1511.1 (5) Å3
  • Z = 4
  • Cu Kα radiation
  • μ = 1.98 mm−1
  • T = 295 K
  • 0.70 × 0.25 × 0.25 mm

Data collection

  • Stoe Stadi-4 four-circle diffractometer
  • Absorption correction: ψ scan (North et al., 1968 [triangle]) T min = 0.749, T max = 0.994
  • 2398 measured reflections
  • 2252 independent reflections
  • 1875 reflections with I > 2σ(I)
  • θmax = 60.0°
  • 3 standard reflections every 60 min intensity decay: 8.8%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.046
  • wR(F 2) = 0.126
  • S = 1.06
  • 2252 reflections
  • 212 parameters
  • H-atom parameters constrained
  • Δρmax = 0.21 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: STADI4 (Stoe & Cie, 1997 [triangle]); cell refinement: STADI4; data reduction: X-RED (Stoe & Cie, 1997 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: XP in SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810004101/zl2270sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810004101/zl2270Isup2.hkl

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

Acknowledgments

We thank the Academy of Sciences of the Republic of Uzbekistan for supporting this study (grant FA–F3–T047).

supplementary crystallographic information

Comment

Among heterocyclic compounds the thieno[2,3-d]pyrimidin-4-ones (Melik-Ogandzhanyan et al., 1985; Csukonyi et al., 1986; Shvedov et al., 1975; Shakhidoyatov 1983; Gevald et al., 1966; Kapustina et al., 1992; Peet et al., 1986; Shodiyev et al., 1993) make up a large group of substances that have various physiological activities (Kapustina et al., 1992; Blaskiewich et al., 1975; Wähäla et al., 2005; Lilienkampf et al., 2007; Han et al., 2007; Moore et al., 2006).

Condensation of 2,3-dimethylthieno[2',3':4,5]pyrimidino[1,2-a]pyridin-4-one with aromatic and heterocyclic aldehydes leads to the formation of new 8-aryliden derivatives. With this purpose in mind the reaction of 2,3-dimethylthieno[2',3':4,5]pyrimidino[1,2-a]pyridin-4-one with furfural was carried by boiling of equimolar amounts of the initial reagents over 4 hours in ethanol in the presence of sodium hydroxide (Bozorov et al., 2009) (Figure 1).

The structure of the synthesized compound has been investigated by 1H NMR and XRD analysis. Figure 2 shows an ortep style plot of the molecular structure of the title compound. One of the methylene groups of the tetrahydropyrido ring (C10, C10A) is disordered over two positions. Refinement of the structure yielded an occupancy ratio of the disordered atoms (i.e. two conformers) of 0.87 (1):0.13 (1).

The π-electronic system of the thiophene, furan and pyrimidinone rings participate in conjugation with the π electrons of the nitrogen atoms as can be seen from the appreciable change of the bond lengths of valence bonds C4═O1 (1.226 (3) Å), C2—C8 (1.479 (3) Å), C12—C2' (1.437 (3) Å) from their standard values (Allen et al., 1987) and from the coplanarity of the thieno[2,3-d]pyrimidin-4-one moiety with the furan ring.

In the crystal structure of the title compound weak intermolecular C—H···X hydrogen bonds (Table 1) are observed as it is often the case in alkaloids (Rajnikant et al., 2005). Of them C3'—H···O1' and C4'—H···N1 lead to the formation of infinite chains, C5A—H···O1 and C6A—H···O1 join these chains in a flat network (Figure 3. and Table 1) parallel to the (1 0 1) plane.

Experimental

0.02 g sodium hydroxide (0.5 mmole) was dissolved in 5 ml ethanol, and 0.234 g (1 mmole) of 2,3-dimethylthieno[2',3':4,5]pyrimidino[1,2-a]pyridin-4-one and 0.106 g (0.092 ml, d═1.1598 g/ml, 1.1 mmole) furfural were added (Figure 1). The mixture was heated to reflux on a water bath for 4 hours. The solvent was distilled off and the residue was recrystallized from a mixture of solvents – benzene: cyclohexane – 5:1. 0.26 g (83.4 %) of the title compound were obtained in the reaction. m.p. 449–451 K.

Yellow crystals suitable for X-ray analysis were obtained from a mixture of benzene and hexane (2:1) at room temperature.

1H NMR (400 MHz, CDCl3): 7.83 (1H, t, J═2.22 Hz, H-12), 7.48 (1H, d, J═1.98 Hz, H-3'), 6.56 (1H, d, J═3.46 Hz, H-5'), 6.45 (1H, dd, J═1.98 Hz, J═3.46 Hz, H-4'), 4.07 (2H, t, J═5.93 Hz, CH2-11), 2.97 (2H, td, J═2.22 Hz, J═6.68 Hz, CH2-9), 2.42 (3H, d, J═0.75 Hz, CH3-5), 2.32 (3H, d, J═0.75 Hz, CH3-6), 1.94-1.99 (2H, m, CH2-10).

Refinement

The H atoms bonded to C atoms were placed geometrically (with C—H distances of 0.98 Å for CH; 0.97 Å for CH2; 0.96 Å for CH3; and 0.93 Å for Car) and included in the refinement in a riding motion approximation with Uiso=1.2Ueq(C) [Uiso=1.5Ueq(C) for methyl H atoms].

Figures

Fig. 1.
Reaction scheme.
Fig. 2.
An Ortep sty;e plot of the structure and the numbering of atoms in (I) (dashed atoms indicate equivalent positions of disordeed atoms).
Fig. 3.
Packing view of the title compound showing the H-bonding networks in the crystal. Minor moiety disordered atoms are omitted for clarity.

Crystal data

C17H16N2O2SF(000) = 656
Mr = 312.39Dx = 1.373 Mg m3
Monoclinic, P21/cMelting point: 448(3) K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54184 Å
a = 16.569 (3) ÅCell parameters from 14 reflections
b = 11.034 (2) Åθ = 10–20°
c = 8.2775 (17) ŵ = 1.98 mm1
β = 93.12 (3)°T = 295 K
V = 1511.1 (5) Å3Prizmatic, yellow
Z = 40.70 × 0.25 × 0.25 mm

Data collection

Stoe Stadi-4 four-circle diffractometer1875 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.000
graphiteθmax = 60.0°, θmin = 2.7°
Scan width (ω) = 1.56 – 1.80, scan ratio 2θ:ω = 1.00 I(Net) and sigma(I) calculated according to Blessing (1987)h = 0→18
Absorption correction: ψ scan (North et al., 1968)k = −12→0
Tmin = 0.749, Tmax = 0.994l = −9→9
2398 measured reflections3 standard reflections every 60 min
2252 independent reflections intensity decay: 8.8%

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.046H-atom parameters constrained
wR(F2) = 0.126w = 1/[σ2(Fo2) + (0.0607P)2 + 0.8817P] where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.004
2252 reflectionsΔρmax = 0.21 e Å3
212 parametersΔρmin = −0.20 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0065 (6)

Special details

Experimental. ψ Scan Reflections used µ * R = 0.00 H K L, θ, χ, Imin/Imax: 2 0 0, 21.5, 84.7, 0.699
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 > 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)

xyzUiso*/UeqOcc. (<1)
O10.90729 (13)0.21420 (19)−0.1624 (3)0.0835 (8)
S70.77689 (4)0.60019 (6)−0.01745 (10)0.0595 (3)
N10.71466 (12)0.37806 (19)0.0356 (3)0.0467 (6)
C20.72119 (14)0.2591 (2)0.0249 (3)0.0418 (6)
N30.78599 (12)0.20424 (19)−0.0432 (3)0.0458 (5)
C40.85116 (15)0.2697 (3)−0.1063 (3)0.0518 (7)
C4A0.84293 (15)0.3988 (2)−0.0951 (3)0.0449 (6)
C50.89660 (15)0.4932 (2)−0.1467 (3)0.0487 (6)
C5A0.97383 (17)0.4694 (3)−0.2303 (4)0.0679 (9)
H5AA0.99860.5451−0.25620.102*
H5AB0.96180.4245−0.32800.102*
H5AC1.01020.4235−0.15990.102*
C60.86857 (16)0.6048 (3)−0.1123 (3)0.0531 (7)
C6A0.90635 (19)0.7268 (3)−0.1409 (4)0.0709 (9)
H6AA0.95400.7164−0.20050.106*
H6AB0.92070.7645−0.03880.106*
H6AC0.86840.7772−0.20160.106*
C7A0.77579 (14)0.4433 (2)−0.0239 (3)0.0450 (6)
C80.65649 (15)0.1844 (2)0.0904 (3)0.0421 (6)
C90.65812 (17)0.0487 (2)0.0699 (3)0.0538 (7)
H9A0.60360.01940.04550.065*0.867 (11)
H9B0.67820.01140.17030.065*0.867 (11)
H9C0.63730.01090.16480.065*0.133 (11)
H9D0.62290.0265−0.02280.065*0.133 (11)
C100.7120 (3)0.0122 (3)−0.0664 (6)0.0553 (13)0.867 (11)
H10A0.7188−0.0751−0.06570.066*0.867 (11)
H10B0.68570.0348−0.16960.066*0.867 (11)
C10A0.7417 (14)0.0010 (18)0.046 (5)0.059 (9)0.133 (11)
H10C0.7690−0.00870.15200.071*0.133 (11)
H10D0.7364−0.0790−0.00170.071*0.133 (11)
C110.79243 (19)0.0704 (3)−0.0502 (4)0.0619 (8)
H11A0.82350.0477−0.14140.074*0.867 (11)
H11B0.82110.04140.04760.074*0.867 (11)
H11C0.78200.0459−0.16190.074*0.133 (11)
H11D0.84790.0487−0.02000.074*0.133 (11)
C120.59817 (14)0.2425 (2)0.1664 (3)0.0462 (6)
H12A0.60220.32650.16780.055*
O1'0.48028 (12)0.28051 (16)0.3048 (3)0.0661 (6)
C2'0.53057 (15)0.1931 (2)0.2458 (3)0.0453 (6)
C3'0.50203 (17)0.0833 (2)0.2865 (3)0.0532 (7)
H3'A0.52470.00880.26250.064*
C4'0.43150 (17)0.1016 (3)0.3722 (4)0.0581 (8)
H4'A0.39890.04210.41440.070*
C5'0.42112 (18)0.2205 (3)0.3803 (4)0.0677 (9)
H5'A0.37900.25800.43090.081*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0666 (14)0.0566 (13)0.132 (2)0.0106 (11)0.0528 (14)−0.0037 (13)
S70.0568 (5)0.0387 (4)0.0861 (6)−0.0057 (3)0.0330 (4)−0.0040 (3)
N10.0458 (12)0.0368 (12)0.0594 (13)−0.0038 (9)0.0206 (10)−0.0035 (9)
C20.0426 (13)0.0371 (14)0.0465 (13)0.0011 (11)0.0084 (11)−0.0033 (11)
N30.0448 (12)0.0374 (12)0.0562 (13)0.0023 (9)0.0121 (10)−0.0027 (9)
C40.0450 (15)0.0491 (16)0.0630 (16)0.0050 (12)0.0176 (13)−0.0004 (13)
C4A0.0391 (13)0.0477 (15)0.0489 (14)0.0007 (11)0.0107 (11)−0.0012 (11)
C50.0412 (14)0.0499 (16)0.0563 (15)−0.0021 (12)0.0144 (12)0.0009 (12)
C5A0.0466 (16)0.068 (2)0.092 (2)−0.0008 (15)0.0275 (15)0.0024 (17)
C60.0466 (15)0.0526 (16)0.0615 (16)−0.0084 (13)0.0175 (13)0.0020 (13)
C6A0.068 (2)0.0541 (18)0.094 (2)−0.0126 (15)0.0291 (17)0.0071 (16)
C7A0.0421 (13)0.0398 (14)0.0543 (15)−0.0018 (11)0.0129 (11)−0.0014 (11)
C80.0442 (14)0.0357 (13)0.0467 (14)−0.0040 (11)0.0061 (11)−0.0004 (10)
C90.0596 (17)0.0386 (15)0.0645 (17)−0.0044 (13)0.0155 (14)−0.0031 (12)
C100.065 (2)0.0360 (17)0.066 (3)0.0019 (16)0.010 (2)−0.0066 (16)
C10A0.048 (13)0.032 (11)0.10 (2)0.004 (9)0.008 (13)0.013 (12)
C110.0681 (19)0.0365 (14)0.083 (2)0.0089 (14)0.0169 (16)−0.0035 (14)
C120.0472 (14)0.0337 (13)0.0587 (15)−0.0056 (11)0.0115 (12)−0.0006 (11)
O1'0.0624 (12)0.0378 (10)0.1018 (15)−0.0008 (9)0.0407 (11)0.0043 (10)
C2'0.0444 (14)0.0357 (13)0.0567 (15)−0.0030 (11)0.0110 (12)−0.0011 (11)
C3'0.0576 (16)0.0346 (14)0.0692 (18)−0.0072 (12)0.0196 (14)−0.0015 (12)
C4'0.0539 (16)0.0467 (16)0.0760 (19)−0.0121 (13)0.0236 (14)0.0027 (13)
C5'0.0569 (17)0.0501 (18)0.100 (2)−0.0057 (14)0.0384 (17)0.0024 (16)

Geometric parameters (Å, °)

O1—C41.226 (3)C9—H9A0.9700
S7—C7A1.732 (3)C9—H9B0.9700
S7—C61.748 (3)C9—H9C0.9700
N1—C21.321 (3)C9—H9D0.9700
N1—C7A1.357 (3)C10—C111.478 (5)
C2—N31.379 (3)C10—H10A0.9700
C2—C81.479 (3)C10—H10B0.9700
N3—C41.422 (3)C10A—C111.41 (2)
N3—C111.482 (3)C10A—H10C0.9700
C4—C4A1.435 (4)C10A—H10D0.9700
C4A—C7A1.377 (3)C11—H11A0.9700
C4A—C51.449 (3)C11—H11B0.9700
C5—C61.352 (4)C11—H11C0.9700
C5—C5A1.510 (4)C11—H11D0.9700
C5A—H5AA0.9600C12—C2'1.437 (3)
C5A—H5AB0.9600C12—H12A0.9300
C5A—H5AC0.9600O1'—C5'1.363 (3)
C6—C6A1.509 (4)O1'—C2'1.381 (3)
C6A—H6AA0.9600C2'—C3'1.349 (3)
C6A—H6AB0.9600C3'—C4'1.414 (4)
C6A—H6AC0.9600C3'—H3'A0.9300
C8—C121.344 (3)C4'—C5'1.325 (4)
C8—C91.506 (3)C4'—H4'A0.9300
C9—C10A1.51 (2)C5'—H5'A0.9300
C9—C101.531 (4)
C7A—S7—C691.33 (12)C8—C9—H9C109.1
C2—N1—C7A116.0 (2)C10A—C9—H9D109.1
N1—C2—N3122.1 (2)C8—C9—H9D109.1
N1—C2—C8117.8 (2)H9C—C9—H9D107.8
N3—C2—C8120.1 (2)C11—C10—C9112.2 (3)
C2—N3—C4123.4 (2)C11—C10—H10A109.2
C2—N3—C11120.8 (2)C9—C10—H10A109.2
C4—N3—C11115.7 (2)C11—C10—H10B109.2
O1—C4—N3119.5 (3)C9—C10—H10B109.2
O1—C4—C4A126.7 (2)H10A—C10—H10B107.9
N3—C4—C4A113.8 (2)C11—C10A—C9117.6 (17)
C7A—C4A—C4117.6 (2)C11—C10A—H10C107.9
C7A—C4A—C5113.2 (2)C9—C10A—H10C107.9
C4—C4A—C5129.2 (2)C11—C10A—H10D107.9
C6—C5—C4A111.6 (2)C9—C10A—H10D107.9
C6—C5—C5A124.3 (2)H10C—C10A—H10D107.2
C4A—C5—C5A124.0 (2)C10A—C11—N3118.1 (9)
C5—C5A—H5AA109.5C10—C11—N3111.7 (3)
C5—C5A—H5AB109.5C10A—C11—H11A130.9
H5AA—C5A—H5AB109.5C10—C11—H11A109.3
C5—C5A—H5AC109.5N3—C11—H11A109.3
H5AA—C5A—H5AC109.5C10—C11—H11B109.3
H5AB—C5A—H5AC109.5N3—C11—H11B109.3
C5—C6—C6A129.0 (2)H11A—C11—H11B107.9
C5—C6—S7112.7 (2)C10A—C11—H11C107.8
C6A—C6—S7118.3 (2)N3—C11—H11C107.8
C6—C6A—H6AA109.5H11B—C11—H11C139.2
C6—C6A—H6AB109.5C10A—C11—H11D107.8
H6AA—C6A—H6AB109.5C10—C11—H11D138.9
C6—C6A—H6AC109.5N3—C11—H11D107.8
H6AA—C6A—H6AC109.5H11C—C11—H11D107.1
H6AB—C6A—H6AC109.5C8—C12—C2'129.2 (2)
N1—C7A—C4A127.0 (2)C8—C12—H12A115.4
N1—C7A—S7121.74 (18)C2'—C12—H12A115.4
C4A—C7A—S7111.21 (19)C5'—O1'—C2'106.6 (2)
C12—C8—C2117.4 (2)C3'—C2'—O1'108.2 (2)
C12—C8—C9123.0 (2)C3'—C2'—C12138.3 (2)
C2—C8—C9119.6 (2)O1'—C2'—C12113.4 (2)
C10A—C9—C8112.6 (8)C2'—C3'—C4'107.9 (2)
C8—C9—C10111.1 (2)C2'—C3'—H3'A126.0
C10A—C9—H9A135.2C4'—C3'—H3'A126.0
C8—C9—H9A109.4C5'—C4'—C3'106.2 (2)
C10—C9—H9A109.4C5'—C4'—H4'A126.9
C8—C9—H9B109.4C3'—C4'—H4'A126.9
C10—C9—H9B109.4C4'—C5'—O1'111.1 (2)
H9A—C9—H9B108.0C4'—C5'—H5'A124.5
C10A—C9—H9C109.1O1'—C5'—H5'A124.5

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C3'—H3'A···O1'i0.932.583.442 (3)154
C4'—H4'A···N1i0.932.663.568 (3)166
C5A—H5AA···O1ii0.962.553.486 (4)166
C6A—H6AA···O1ii0.962.623.571 (4)171

Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+2, y+1/2, −z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: ZL2270).

References

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