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Acta Cryst. (2012). E68, o3099    [ doi:10.1107/S1600536812041748 ]

Ethyl 7-methyl-2-((1-methyl-1H-pyrrol-2-yl)methylene)-3-oxo-5-phenyl-3,5-dihydro-2H-thiazolo[3,2-a]pyrimidine-6-carboxylate

J. Hu, X.-X. Wu, X.-Q. Shen, L.-G. Tang and X.-K. Li

Abstract top

In the structure of the title compound, C22H21N3O3S, the thiazole ring forms dihedral angles of 88.83 (7) and 9.39 (9)°, respectively, with the benzene and pyrrole rings. The dihydropyrimidine ring adopts a flattened boat conformation. The olefinic double bond is in a Z conformation.

Comment top

Thiazolinone and their derivatives have attracted continuing interest over the years because of their varied biological activities (Shah & Desai,2007), such as antifungal (Mehta et al., 2006), antibacterial (Subudhi et al., 2007), anti-tumor (Zhou et al., 2008), anti-HIV and anti-inflammatory (Srivastava et al., 2006). 3,4-Dihydropyrimidin-2(1H)-ones (DHPMs) are known for more than a century and have attracted considerable attention because of their wide spectrum of therapeutic and pharmacological properties. DHPMs have been used as antibacterial, antifungal (Ashok et al., 2007), antiviral (Hurst & Hull, 1961), anti-inflammatory (Bahekar & Shinde, 2004), antioxidative properties and noteworthy, as well as calcium channel modulators (Magerramov et al., 2006). Herein, we report in the present work based on the pharmacological principle of stacking, such biologically active groups as DHPMs was introduced to thiazolinone, with a view to get new compounds with better bioactivity.

In continuation of our studies on heterocyclic compounds, we report the crystal structure of the title compound. The fused thiazole ring has usual geometry as observed in other thiazolo[3,2-a]pyrimidine compounds (Hou, 2009; Zhao et al., 2011). The thiazole ring makes dihedral angles of 88.83 (7) and 9.39 (9)° with the benzene ring and pyrrole ring, respectively. The pyrimidine ring adopts a flattened boat conformation. The C2–C17 distance, 1.345 (2) Å, confirms this as a double bond and the molecule adopts a Z conformation with respect to this bond (Fig. 1).

Related literature top

For related structures, see: Hou (2009); Zhao et al. (2011). For background to the biological properties of fused thiazolo[3,2-a]pyrimidine derivatives, see: Ashok et al. (2007); Bahekar & Shinde (2004); Hurst & Hull (1961); Mehta et al. (2006); Shah & Desai (2007); Srivastava et al. (2006); Subudhi et al. (2007); Magerramov et al. (2006); Zhou et al. (2008).

Experimental top

In a typical procedure of one pot Biginelli reaction, sulfamic acid (0.4 mol) was added to a solution of substituted benzaldehyde (0.5 mol), ethyl acetylacetate (0.6 mol), and thiourea (0.75 mol) in ethanol and reflux at 351 K for 2 h. When the reaction was finished, the mixture was cooled to room temperature and filtered. The product ethyl 2-mercapto-4-methyl-6 -phenyl-1,6-dihydropyrimidine-5-carboxylate was washed with water, and then dried in vacuum as a white solid.

To a stirred solution of ethyl ] 2-mercapto-4-methyl-6-phenyl-1,6-dihydropyrimidine-5-carboxylate (2 mmol) and ethyl chloroacetate (2 mmol) in ethanol (10 ml) pyridine (2 mmol) was added.The reaction was heated at refluxing temperature for 4 h. Then 1-methyl-1H-pyrrole-2-carbaldehyde (2 mmol) and morpholine (2 mmol) was added to the mixture without further treatment until the reaction finished. The mixture was then cooled to room temperature, filtered and washed with water to obtain crude product. The resulting yellow solid was collected and recrystallized from acetic acid, then single crystals were grown in CH2Cl2/CH3OH mixture (2:1). Yield 45.6%.

1H NMR (DMSO-d6) δ: 1.111 (3H, m, 6–CH3), 4.030 (2H, m, 6–CH2), 2.380 (3H, s, N–CH3), 3.730 (3H, s, 7–CH3), 6.035 (H, s, 5–CH), 6.317 (1H, m, pyrrole), 6.576(1H, m, pyrrole), 7.213 (1H, m, pyrrole), 7.284–7.340 (5H, m, Ar—H), 7.625 (1H, s, =CH). ESI-MS m/z: 408.4 (M)+, 430.3 (M+Na)+, calcd for C22H21N3O3S 407.49.

Refinement top

The H atoms were positioned geometrically (C—H = 0.93 – 0.98 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 30% displacement ellipsoids for the non-hydrogen atoms. Hydrogen atoms are drawn as spheres of arbitrary radius.
Ethyl 7-methyl-2-((1-methyl-1H-pyrrol-2-yl)methylene)-3-oxo-5- phenyl-3,5-dihydro-2H-thiazolo[3,2-a]pyrimidine-6-carboxylate top
Crystal data top
C22H21N3O3SF(000) = 856
Mr = 407.48Dx = 1.371 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4867 reflections
a = 11.8187 (10) Åθ = 5.0–56.3°
b = 10.2911 (9) ŵ = 0.19 mm−1
c = 16.2290 (14) ÅT = 293 K
β = 90.584 (2)°Prismatic, red
V = 1973.8 (3) Å30.32 × 0.24 × 0.16 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		3877 independent reflections
Radiation source: fine-focus sealed tube3433 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
phi and ω scansθmax = 26.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2002)		h = −14→14
Tmin = 0.814, Tmax = 1.000k = −12→11
10415 measured reflectionsl = −20→19
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0574P)2 + 0.5784P]
where P = (Fo2 + 2Fc2)/3
3877 reflections(Δ/σ)max < 0.001
265 parametersΔρmax = 0.30 e Å−3
0 restraintsΔρmin = −0.19 e Å−3
Crystal data top
C22H21N3O3SV = 1973.8 (3) Å3
Mr = 407.48Z = 4
Monoclinic, P21/nMo Kα radiation
a = 11.8187 (10) ŵ = 0.19 mm−1
b = 10.2911 (9) ÅT = 293 K
c = 16.2290 (14) Å0.32 × 0.24 × 0.16 mm
β = 90.584 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		3877 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2002)		3433 reflections with I > 2σ(I)
Tmin = 0.814, Tmax = 1.000Rint = 0.020
10415 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.109Δρmax = 0.30 e Å−3
S = 1.05Δρmin = −0.19 e Å−3
3877 reflectionsAbsolute structure: ?
265 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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
S10.45859 (3)0.25287 (4)0.01131 (2)0.04128 (14)
N10.36364 (10)0.46192 (12)0.06560 (7)0.0318 (3)
N20.26786 (11)0.35881 (14)−0.04481 (8)0.0402 (3)
N30.76832 (11)0.15037 (14)0.18041 (8)0.0413 (3)
O10.48083 (10)0.52724 (11)0.17107 (8)0.0471 (3)
O20.05024 (13)0.69653 (15)−0.05111 (10)0.0735 (5)
O30.14144 (10)0.76092 (11)0.06154 (7)0.0473 (3)
C10.45910 (12)0.45135 (15)0.11618 (9)0.0337 (3)
C20.52334 (12)0.33419 (15)0.09404 (9)0.0343 (3)
C30.34879 (12)0.36725 (15)0.00763 (9)0.0338 (3)
C40.19135 (13)0.46391 (15)−0.04784 (9)0.0362 (3)
C50.19370 (12)0.56033 (15)0.00841 (9)0.0336 (3)
C60.27014 (12)0.55164 (14)0.08448 (9)0.0316 (3)
H60.30140.63790.09650.038*
C70.20515 (11)0.50354 (15)0.15961 (9)0.0330 (3)
C80.16948 (14)0.59098 (18)0.21843 (10)0.0446 (4)
H80.18830.67840.21380.054*
C90.10566 (17)0.5486 (2)0.28426 (11)0.0588 (5)
H90.08090.60810.32330.071*
C100.07856 (16)0.4197 (2)0.29245 (11)0.0573 (5)
H100.03600.39190.33700.069*
C110.11433 (15)0.3322 (2)0.23496 (11)0.0520 (4)
H110.09670.24460.24060.062*
C120.17686 (14)0.37389 (17)0.16826 (10)0.0422 (4)
H120.20010.31410.12890.051*
C130.11228 (15)0.45209 (19)−0.12025 (11)0.0485 (4)
H13A0.05020.5112−0.11370.073*
H13B0.08400.3648−0.12350.073*
H13C0.15200.4728−0.16990.073*
C140.12023 (13)0.67570 (16)0.00121 (10)0.0396 (4)
C150.07470 (16)0.87886 (19)0.05991 (13)0.0561 (5)
H15A−0.00340.85910.07270.067*
H15B0.07680.91730.00540.067*
C160.1209 (2)0.9705 (3)0.12081 (18)0.0907 (9)
H16A0.11360.93450.17510.136*
H16B0.07991.05090.11760.136*
H16C0.19930.98610.10960.136*
C170.61539 (12)0.29575 (16)0.13690 (10)0.0371 (3)
H170.64110.35290.17730.045*
C180.67851 (12)0.17881 (16)0.12828 (10)0.0384 (4)
C190.66600 (15)0.07268 (18)0.07624 (12)0.0503 (4)
H190.61230.06430.03430.060*
C200.74750 (17)−0.01876 (19)0.09753 (13)0.0572 (5)
H200.7581−0.09940.07290.069*
C210.80908 (15)0.03176 (18)0.16125 (12)0.0516 (4)
H210.8697−0.00910.18750.062*
C220.81581 (16)0.23339 (19)0.24420 (13)0.0548 (5)
H22A0.87050.18530.27600.082*
H22B0.75650.26280.27960.082*
H22C0.85180.30690.21920.082*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0416 (2)0.0415 (2)0.0407 (2)0.01238 (17)−0.00433 (17)−0.00727 (16)
N10.0271 (6)0.0325 (7)0.0358 (6)0.0032 (5)−0.0009 (5)−0.0010 (5)
N20.0418 (7)0.0412 (8)0.0373 (7)0.0070 (6)−0.0067 (6)−0.0036 (6)
N30.0334 (7)0.0417 (8)0.0488 (8)0.0044 (6)−0.0002 (6)0.0088 (6)
O10.0408 (6)0.0430 (7)0.0573 (7)0.0047 (5)−0.0145 (5)−0.0128 (6)
O20.0766 (10)0.0619 (9)0.0813 (10)0.0293 (8)−0.0421 (8)−0.0117 (8)
O30.0500 (7)0.0418 (7)0.0499 (7)0.0171 (5)−0.0098 (5)−0.0021 (5)
C10.0281 (7)0.0335 (8)0.0396 (8)−0.0014 (6)−0.0007 (6)0.0012 (6)
C20.0296 (7)0.0346 (8)0.0388 (8)0.0004 (6)0.0019 (6)0.0010 (6)
C30.0346 (7)0.0338 (8)0.0331 (7)0.0041 (6)0.0019 (6)0.0005 (6)
C40.0334 (7)0.0393 (8)0.0359 (7)0.0015 (6)−0.0023 (6)0.0039 (6)
C50.0289 (7)0.0357 (8)0.0363 (7)0.0019 (6)−0.0008 (6)0.0055 (6)
C60.0283 (7)0.0288 (7)0.0376 (8)0.0036 (6)−0.0016 (6)−0.0014 (6)
C70.0263 (7)0.0398 (8)0.0328 (7)0.0047 (6)−0.0051 (6)−0.0007 (6)
C80.0474 (9)0.0451 (10)0.0413 (9)0.0062 (8)−0.0028 (7)−0.0075 (7)
C90.0566 (11)0.0806 (15)0.0395 (9)0.0131 (10)0.0064 (8)−0.0122 (9)
C100.0463 (10)0.0845 (16)0.0412 (9)0.0007 (10)0.0076 (8)0.0094 (9)
C110.0436 (9)0.0572 (11)0.0554 (10)−0.0039 (8)0.0033 (8)0.0114 (9)
C120.0403 (8)0.0430 (9)0.0433 (9)0.0009 (7)0.0033 (7)−0.0006 (7)
C130.0467 (9)0.0545 (11)0.0442 (9)0.0063 (8)−0.0121 (7)−0.0035 (8)
C140.0358 (8)0.0402 (9)0.0427 (8)0.0044 (7)−0.0033 (7)0.0062 (7)
C150.0539 (11)0.0439 (10)0.0703 (12)0.0189 (8)−0.0066 (9)−0.0017 (9)
C160.0925 (18)0.0751 (17)0.1037 (19)0.0376 (14)−0.0330 (15)−0.0384 (14)
C170.0305 (7)0.0371 (8)0.0437 (8)0.0001 (6)−0.0004 (6)0.0003 (7)
C180.0294 (7)0.0393 (9)0.0465 (9)0.0029 (6)0.0007 (6)0.0054 (7)
C190.0444 (9)0.0479 (10)0.0584 (11)0.0083 (8)−0.0045 (8)−0.0052 (8)
C200.0566 (11)0.0425 (10)0.0725 (13)0.0140 (9)0.0016 (10)−0.0040 (9)
C210.0438 (9)0.0447 (10)0.0663 (12)0.0142 (8)0.0024 (8)0.0129 (9)
C220.0479 (10)0.0532 (11)0.0628 (12)0.0022 (8)−0.0167 (9)0.0072 (9)
Geometric parameters (Å, º) top
S1—C21.7515 (15)C9—H90.9300
S1—C31.7525 (15)C10—C111.367 (3)
N1—C31.3644 (19)C10—H100.9300
N1—C11.3927 (18)C11—C121.385 (2)
N1—C61.4747 (18)C11—H110.9300
N2—C31.2767 (19)C12—H120.9300
N2—C41.410 (2)C13—H13A0.9600
N3—C211.350 (2)C13—H13B0.9600
N3—C181.382 (2)C13—H13C0.9600
N3—C221.451 (2)C15—C161.467 (3)
O1—C11.2103 (18)C15—H15A0.9700
O2—C141.1986 (19)C15—H15B0.9700
O3—C141.336 (2)C16—H16A0.9600
O3—C151.448 (2)C16—H16B0.9600
C1—C21.471 (2)C16—H16C0.9600
C2—C171.345 (2)C17—C181.424 (2)
C4—C51.348 (2)C17—H170.9300
C4—C131.499 (2)C18—C191.388 (2)
C5—C141.475 (2)C19—C201.388 (3)
C5—C61.525 (2)C19—H190.9300
C6—C71.530 (2)C20—C211.362 (3)
C6—H60.9800C20—H200.9300
C7—C81.381 (2)C21—H210.9300
C7—C121.383 (2)C22—H22A0.9600
C8—C91.384 (3)C22—H22B0.9600
C8—H80.9300C22—H22C0.9600
C9—C101.371 (3)
C2—S1—C391.30 (7)C7—C12—C11120.65 (16)
C3—N1—C1116.64 (12)C7—C12—H12119.7
C3—N1—C6119.93 (12)C11—C12—H12119.7
C1—N1—C6122.05 (12)C4—C13—H13A109.5
C3—N2—C4116.54 (13)C4—C13—H13B109.5
C21—N3—C18108.92 (15)H13A—C13—H13B109.5
C21—N3—C22124.10 (15)C4—C13—H13C109.5
C18—N3—C22126.96 (14)H13A—C13—H13C109.5
C14—O3—C15116.02 (13)H13B—C13—H13C109.5
O1—C1—N1123.23 (14)O2—C14—O3121.64 (15)
O1—C1—C2127.04 (14)O2—C14—C5126.98 (16)
N1—C1—C2109.69 (12)O3—C14—C5111.37 (13)
C17—C2—C1122.10 (14)O3—C15—C16109.13 (16)
C17—C2—S1126.93 (13)O3—C15—H15A109.9
C1—C2—S1110.87 (10)C16—C15—H15A109.9
N2—C3—N1126.75 (14)O3—C15—H15B109.9
N2—C3—S1121.76 (12)C16—C15—H15B109.9
N1—C3—S1111.48 (10)H15A—C15—H15B108.3
C5—C4—N2122.14 (13)C15—C16—H16A109.5
C5—C4—C13126.79 (15)C15—C16—H16B109.5
N2—C4—C13111.07 (14)H16A—C16—H16B109.5
C4—C5—C14122.06 (14)C15—C16—H16C109.5
C4—C5—C6120.85 (13)H16A—C16—H16C109.5
C14—C5—C6117.05 (13)H16B—C16—H16C109.5
N1—C6—C5107.91 (11)C2—C17—C18128.30 (15)
N1—C6—C7110.27 (12)C2—C17—H17115.8
C5—C6—C7111.47 (11)C18—C17—H17115.8
N1—C6—H6109.0N3—C18—C19106.40 (14)
C5—C6—H6109.0N3—C18—C17121.26 (15)
C7—C6—H6109.0C19—C18—C17132.26 (15)
C8—C7—C12118.85 (15)C18—C19—C20108.23 (17)
C8—C7—C6119.96 (15)C18—C19—H19125.9
C12—C7—C6121.13 (13)C20—C19—H19125.9
C7—C8—C9120.06 (18)C21—C20—C19107.12 (17)
C7—C8—H8120.0C21—C20—H20126.4
C9—C8—H8120.0C19—C20—H20126.4
C10—C9—C8120.59 (18)N3—C21—C20109.33 (16)
C10—C9—H9119.7N3—C21—H21125.3
C8—C9—H9119.7C20—C21—H21125.3
C11—C10—C9119.81 (17)N3—C22—H22A109.5
C11—C10—H10120.1N3—C22—H22B109.5
C9—C10—H10120.1H22A—C22—H22B109.5
C10—C11—C12120.04 (19)N3—C22—H22C109.5
C10—C11—H11120.0H22A—C22—H22C109.5
C12—C11—H11120.0H22B—C22—H22C109.5
C3—N1—C1—O1−178.40 (14)C5—C6—C7—C8−101.17 (16)
C6—N1—C1—O1−11.8 (2)N1—C6—C7—C12−43.80 (18)
C3—N1—C1—C2−0.46 (18)C5—C6—C7—C1276.03 (17)
C6—N1—C1—C2166.11 (12)C12—C7—C8—C9−0.6 (2)
O1—C1—C2—C172.4 (2)C6—C7—C8—C9176.68 (15)
N1—C1—C2—C17−175.41 (14)C7—C8—C9—C100.9 (3)
O1—C1—C2—S1179.05 (14)C8—C9—C10—C11−0.3 (3)
N1—C1—C2—S11.22 (15)C9—C10—C11—C12−0.6 (3)
C3—S1—C2—C17175.15 (15)C8—C7—C12—C11−0.3 (2)
C3—S1—C2—C1−1.27 (11)C6—C7—C12—C11−177.55 (14)
C4—N2—C3—N15.9 (2)C10—C11—C12—C70.9 (3)
C4—N2—C3—S1−173.22 (11)C15—O3—C14—O20.3 (2)
C1—N1—C3—N2−179.70 (15)C15—O3—C14—C5179.36 (14)
C6—N1—C3—N213.4 (2)C4—C5—C14—O22.3 (3)
C1—N1—C3—S1−0.50 (16)C6—C5—C14—O2−175.46 (18)
C6—N1—C3—S1−167.38 (10)C4—C5—C14—O3−176.79 (14)
C2—S1—C3—N2−179.73 (14)C6—C5—C14—O35.49 (19)
C2—S1—C3—N11.03 (11)C14—O3—C15—C16−170.47 (19)
C3—N2—C4—C5−8.6 (2)C1—C2—C17—C18172.86 (15)
C3—N2—C4—C13170.92 (14)S1—C2—C17—C18−3.2 (3)
N2—C4—C5—C14174.67 (14)C21—N3—C18—C19−0.08 (18)
C13—C4—C5—C14−4.7 (2)C22—N3—C18—C19178.08 (16)
N2—C4—C5—C6−7.7 (2)C21—N3—C18—C17177.00 (14)
C13—C4—C5—C6172.92 (15)C22—N3—C18—C17−4.8 (2)
C3—N1—C6—C5−26.08 (17)C2—C17—C18—N3−176.53 (15)
C1—N1—C6—C5167.78 (13)C2—C17—C18—C19−0.3 (3)
C3—N1—C6—C795.89 (15)N3—C18—C19—C200.3 (2)
C1—N1—C6—C7−70.25 (17)C17—C18—C19—C20−176.32 (17)
C4—C5—C6—N123.55 (19)C18—C19—C20—C21−0.4 (2)
C14—C5—C6—N1−158.71 (12)C18—N3—C21—C20−0.2 (2)
C4—C5—C6—C7−97.67 (16)C22—N3—C21—C20−178.41 (17)
C14—C5—C6—C780.07 (16)C19—C20—C21—N30.4 (2)
N1—C6—C7—C8139.00 (14)
Acknowledgements top

This work was supported by the Zhejiang Provincial Natural Science Foundation of China (grants No. Y12H160033 and Y4110197) and the project of Wenzhou Sci & Tech Bureau (Y20100273). The X-ray crystallographic facility at the Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, is gratefully acknowledged.

references
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