supplementary materials


lh5628 scheme

Acta Cryst. (2013). E69, o1262    [ doi:10.1107/S1600536813019132 ]

Methyl 5-(4-acetoxyphenyl)-2-(2-bromobenzylidine)-7-methyl-3-oxo-2,3-dihydro-5H-1,3-thiazolo[3,2-a]pyrimidine-6-carboxylate

N. Fathima, H. Nagarajaiah and N. S. Begum

Abstract top

In the title molecule, C24H19BrN2O5S, the pyrimidine ring is in a flattened half-chair conformation and the 4-acetoxyphenyl group is substituted axially to this ring. The thiazole ring is essentially planar [with a maximum deviation of 0.012 (2) Å for the N atom] and forms dihedral angles of 17.65 (13) and 88.95 (11)° with the bromo- and acetoxy-substituted benzene rings, respectively. The dihedral angle between the benzene rings is 81.84 (13) Å. In the crystal, pairs of weak C-H...O hydrogen bonds lead to the formation of inversion dimers. A weak C-H...[pi] interaction and [pi]-[pi] stacking interactions with centroid-centroid distances of 3.5903 (14) Å are observed.

Comment top

Dihydropyrimidines (DHPM) exhibit a broad range of therapeutic and pharmacological properties (Alam et al., 2010). These non-planar heterocyclic compounds have interesting multifaceted pharmacological profiles such as calcium channel modulation, antitumor, antiviral, antibacterial, anti-inflammatory and antimicrobial activities (Kappe et al., 2000; Atwal et al.. 1991). In addition, a few DHPM derivatives have even emerged as orally active antihypertensive agents (Rovnyak et al., 1992).

The molecular structure of the title compound is shown in Fig. 1. The 4-acetoxy substituted benzene ring is axially substituted to the pyrimidine ring. The central pyrimidine ring adopts a half chair conformation with deviations of 0.107 (2) and -0.200 (2) Å for N1 and C5 respectively from the remaining four ring atoms (C6/C7/C9/N2). In the crystal, pairs of weak C—H···O hydrogen bonds form inversion dimers with a graph set notation of R22(16) (Bernstein et al., 1995) as shown in Fig. 2. The crystal structure of the title compound shows different type of intermolecular interactions compared to a similar structure reported earlier (Nagarajaiah et al., 2012). In addition, there are intermolecular π···π interactions between inversion-related thiazole rings with a centroid to centroid distance of 3.5903 (14)Å. A weak C—H···π(ring) interaction is also observed (see Table 1, where Cg is the centroid of the C5/C6/C7/N2/C9/N1 ring). Another example of a related crystal structure has been published in the literature (Nagarajaiah et al., 2011).

Related literature top

For the biological activity of dihydropyrimidines, see: Alam et al. (2010); Kappe et al. (2000); Atwal et al. (1991); Rovnyak et al. (1992). For related structures, see: Nagarajaiah et al. (2011, 2012). For hydrogen-bond graph-set motifs, see: Bernstein et al. (1995).

Experimental top

The compound 2-(2-bromo-benzylidene)-4-(4-hydroxy-phenyl)6-methyl-3-oxo-2,3-dihydro-thieno[2,3-bpyridine-5-carboxylic acid (2.0 g) was mixed with acetic anhydride (10 ml) and refluxed for about 4 h. The reaction mixture was cooled and diluted by the addition of water (20 ml). The solid separated was washed with water, filtered, and dried (Yield: 2.63 g, 80% and mp 418 K). Pale yellow crystals suitable for diffraction were obtained by slow evaporation of a solution of the title compound in chloroform.

Refinement top

The H atoms were placed in calculated positions in a riding-model approximation with C—H = 0.93 Å, 0.96 Å and 0.98 Å for aryl, methyl and methyne H-atoms respectively, with Uiso(H) = 1.5Ueq(C) for methyl H atoms and Uiso(H) = 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1998); 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) and CAMERON (Watkin et al., 1996); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability ellipsoids.
[Figure 2] Fig. 2. The packing of the title compound showing weak C—H···O hydrogen bonds with dashed lines. H-atoms not involved in hydrogen bonding have been excluded.
Methyl 5-(4-acetoxyphenyl)-2-(2-bromobenzylidine)-7-methyl-3-oxo-2,3-dihydro-5H-1,3-thiazolo[3,2-a]pyrimidine-6-carboxylate top
Crystal data top
C24H19BrN2O5SZ = 2
Mr = 527.38F(000) = 536
Triclinic, P1Dx = 1.593 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.6018 (5) ÅCell parameters from 4777 reflections
b = 11.9648 (7) Åθ = 2.8–27.0°
c = 14.0877 (9) ŵ = 2.00 mm1
α = 106.425 (1)°T = 296 K
β = 104.700 (2)°Block, yellow
γ = 106.296 (1)°0.18 × 0.16 × 0.16 mm
V = 1099.75 (12) Å3
Data collection top
Bruker SMART APEX CCD detector
diffractometer
4777 independent reflections
Radiation source: fine-focus sealed tube3989 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω scansθmax = 27.0°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
h = 79
Tmin = 0.714, Tmax = 0.740k = 1515
9029 measured reflectionsl = 1716
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0443P)2 + 0.7937P]
where P = (Fo2 + 2Fc2)/3
4777 reflections(Δ/σ)max < 0.001
301 parametersΔρmax = 0.58 e Å3
0 restraintsΔρmin = 0.61 e Å3
Crystal data top
C24H19BrN2O5Sγ = 106.296 (1)°
Mr = 527.38V = 1099.75 (12) Å3
Triclinic, P1Z = 2
a = 7.6018 (5) ÅMo Kα radiation
b = 11.9648 (7) ŵ = 2.00 mm1
c = 14.0877 (9) ÅT = 296 K
α = 106.425 (1)°0.18 × 0.16 × 0.16 mm
β = 104.700 (2)°
Data collection top
Bruker SMART APEX CCD detector
diffractometer
4777 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
3989 reflections with I > 2σ(I)
Tmin = 0.714, Tmax = 0.740Rint = 0.026
9029 measured reflectionsθmax = 27.0°
Refinement top
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.096Δρmax = 0.58 e Å3
S = 1.05Δρmin = 0.61 e Å3
4777 reflectionsAbsolute structure: ?
301 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
C10.3032 (4)0.5765 (2)0.84902 (18)0.0216 (5)
H1A0.42120.60450.90930.032*
H1B0.25070.48620.81640.032*
H1C0.20830.60400.87160.032*
C20.3542 (3)0.5692 (2)0.42420 (17)0.0137 (4)
C30.4784 (3)0.6889 (2)0.51728 (17)0.0135 (4)
C40.6434 (4)0.9217 (2)1.08072 (18)0.0294 (6)
H4A0.77320.92101.10310.044*
H4B0.58110.90431.12910.044*
H4C0.65171.00301.08000.044*
C50.5037 (3)0.7934 (2)0.70450 (16)0.0125 (4)
H50.64500.83950.72540.015*
C60.4688 (3)0.7494 (2)0.79134 (17)0.0139 (4)
C70.3495 (3)0.6308 (2)0.77040 (17)0.0141 (4)
C80.5830 (3)0.8511 (2)0.89783 (17)0.0164 (5)
C90.3027 (3)0.5690 (2)0.59347 (17)0.0129 (4)
C100.2005 (3)0.8465 (2)0.67420 (17)0.0164 (5)
H100.13800.77440.68440.020*
C110.3962 (3)0.8789 (2)0.68289 (16)0.0129 (4)
C120.4888 (3)0.9866 (2)0.66788 (18)0.0169 (5)
H120.61961.00900.67370.020*
C130.3871 (4)1.0614 (2)0.64419 (18)0.0196 (5)
H130.44891.13330.63360.024*
C140.1933 (4)1.0274 (2)0.63663 (17)0.0177 (5)
C150.0973 (3)0.9204 (2)0.65043 (19)0.0190 (5)
H150.03390.89800.64400.023*
C160.0214 (4)1.1615 (2)0.6767 (2)0.0237 (5)
C170.0856 (4)1.2323 (2)0.6298 (2)0.0259 (6)
H17A0.14631.26710.67630.039*
H17B0.18481.17600.56200.039*
H17C0.00571.29910.62130.039*
C180.3621 (3)0.5584 (2)0.32793 (17)0.0145 (4)
H180.45430.62750.32660.017*
C190.2483 (3)0.4550 (2)0.22544 (18)0.0163 (5)
C200.1439 (3)0.3325 (2)0.21514 (19)0.0180 (5)
H200.14640.31600.27600.022*
C210.0370 (4)0.2353 (2)0.1167 (2)0.0244 (5)
H210.03140.15500.11210.029*
C220.0323 (4)0.2580 (3)0.0253 (2)0.0322 (6)
H220.04010.19310.04080.039*
C230.1350 (5)0.3770 (3)0.0321 (2)0.0355 (7)
H230.13310.39220.02930.043*
C240.2407 (4)0.4736 (2)0.13075 (19)0.0257 (6)
Br10.37745 (6)0.63467 (3)0.13393 (2)0.04578 (13)
N10.4376 (3)0.68110 (17)0.60657 (14)0.0122 (4)
N20.2509 (3)0.53974 (17)0.66529 (14)0.0150 (4)
O10.5953 (2)0.78204 (15)0.51788 (12)0.0176 (3)
O20.7097 (2)0.94816 (15)0.91182 (13)0.0216 (4)
O30.5290 (3)0.82642 (16)0.97517 (13)0.0251 (4)
O40.0946 (3)1.10282 (16)0.60848 (13)0.0243 (4)
O50.0390 (4)1.1543 (2)0.76119 (17)0.0451 (6)
S10.20567 (8)0.46190 (5)0.46166 (4)0.01442 (13)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0278 (13)0.0208 (12)0.0168 (11)0.0060 (10)0.0100 (10)0.0095 (9)
C20.0122 (11)0.0147 (10)0.0162 (10)0.0067 (9)0.0051 (9)0.0073 (9)
C30.0142 (11)0.0164 (11)0.0136 (10)0.0087 (9)0.0055 (8)0.0076 (9)
C40.0452 (17)0.0241 (13)0.0095 (11)0.0075 (12)0.0061 (11)0.0022 (10)
C50.0119 (10)0.0130 (10)0.0105 (9)0.0036 (8)0.0030 (8)0.0036 (8)
C60.0152 (11)0.0178 (11)0.0109 (10)0.0093 (9)0.0047 (8)0.0055 (9)
C70.0158 (11)0.0173 (11)0.0124 (10)0.0081 (9)0.0065 (9)0.0070 (9)
C80.0202 (12)0.0189 (11)0.0129 (10)0.0118 (10)0.0047 (9)0.0067 (9)
C90.0119 (10)0.0137 (10)0.0130 (10)0.0062 (9)0.0031 (8)0.0051 (8)
C100.0162 (11)0.0138 (10)0.0167 (11)0.0028 (9)0.0054 (9)0.0057 (9)
C110.0150 (11)0.0131 (10)0.0081 (9)0.0044 (9)0.0032 (8)0.0021 (8)
C120.0165 (11)0.0170 (11)0.0180 (11)0.0059 (9)0.0087 (9)0.0061 (9)
C130.0283 (13)0.0149 (11)0.0195 (11)0.0085 (10)0.0119 (10)0.0090 (9)
C140.0257 (13)0.0187 (11)0.0119 (10)0.0139 (10)0.0058 (9)0.0055 (9)
C150.0138 (11)0.0199 (11)0.0216 (11)0.0062 (9)0.0040 (9)0.0079 (9)
C160.0229 (13)0.0229 (12)0.0249 (13)0.0114 (11)0.0065 (10)0.0075 (10)
C170.0267 (14)0.0229 (13)0.0294 (13)0.0148 (11)0.0075 (11)0.0085 (11)
C180.0148 (11)0.0145 (10)0.0152 (10)0.0067 (9)0.0055 (9)0.0058 (9)
C190.0153 (11)0.0206 (11)0.0150 (10)0.0100 (10)0.0059 (9)0.0061 (9)
C200.0148 (11)0.0212 (12)0.0186 (11)0.0080 (10)0.0076 (9)0.0060 (9)
C210.0181 (12)0.0206 (12)0.0249 (13)0.0029 (10)0.0067 (10)0.0005 (10)
C220.0327 (15)0.0285 (14)0.0182 (12)0.0047 (12)0.0028 (11)0.0027 (11)
C230.0506 (18)0.0353 (16)0.0148 (12)0.0130 (14)0.0091 (12)0.0072 (11)
C240.0346 (15)0.0217 (12)0.0172 (12)0.0082 (11)0.0081 (11)0.0059 (10)
Br10.0837 (3)0.02598 (16)0.01761 (15)0.00523 (15)0.01693 (15)0.01100 (11)
N10.0133 (9)0.0127 (9)0.0109 (8)0.0053 (7)0.0046 (7)0.0046 (7)
N20.0154 (9)0.0158 (9)0.0133 (9)0.0043 (8)0.0053 (7)0.0063 (7)
O10.0202 (8)0.0156 (8)0.0158 (8)0.0038 (7)0.0076 (7)0.0063 (6)
O20.0247 (9)0.0173 (8)0.0163 (8)0.0032 (7)0.0052 (7)0.0041 (7)
O30.0368 (11)0.0193 (8)0.0110 (8)0.0030 (8)0.0080 (7)0.0027 (7)
O40.0357 (10)0.0278 (9)0.0220 (9)0.0226 (8)0.0133 (8)0.0143 (7)
O50.0676 (16)0.0675 (16)0.0336 (11)0.0522 (14)0.0300 (11)0.0293 (11)
S10.0143 (3)0.0142 (3)0.0112 (2)0.0025 (2)0.0034 (2)0.0038 (2)
Geometric parameters (Å, º) top
C1—C71.500 (3)C11—C121.385 (3)
C1—H1A0.9600C12—C131.391 (3)
C1—H1B0.9600C12—H120.9300
C1—H1C0.9600C13—C141.381 (4)
C2—C181.344 (3)C13—H130.9300
C2—C31.487 (3)C14—C151.378 (3)
C2—S11.754 (2)C14—O41.402 (3)
C3—O11.211 (3)C15—H150.9300
C3—N11.391 (3)C16—O51.195 (3)
C4—O31.448 (3)C16—O41.354 (3)
C4—H4A0.9600C16—C171.497 (3)
C4—H4B0.9600C17—H17A0.9600
C4—H4C0.9600C17—H17B0.9600
C5—N11.478 (3)C17—H17C0.9600
C5—C61.515 (3)C18—C191.456 (3)
C5—C111.525 (3)C18—H180.9300
C5—H50.9800C19—C241.403 (3)
C6—C71.352 (3)C19—C201.403 (3)
C6—C81.483 (3)C20—C211.387 (3)
C7—N21.417 (3)C20—H200.9300
C8—O21.209 (3)C21—C221.382 (4)
C8—O31.335 (3)C21—H210.9300
C9—N21.275 (3)C22—C231.381 (4)
C9—N11.370 (3)C22—H220.9300
C9—S11.750 (2)C23—C241.384 (4)
C10—C151.391 (3)C23—H230.9300
C10—C111.391 (3)C24—Br11.898 (3)
C10—H100.9300
C7—C1—H1A109.5C14—C13—H13120.4
C7—C1—H1B109.5C12—C13—H13120.4
H1A—C1—H1B109.5C15—C14—C13121.7 (2)
C7—C1—H1C109.5C15—C14—O4121.2 (2)
H1A—C1—H1C109.5C13—C14—O4117.1 (2)
H1B—C1—H1C109.5C14—C15—C10118.7 (2)
C18—C2—C3119.9 (2)C14—C15—H15120.7
C18—C2—S1129.72 (18)C10—C15—H15120.7
C3—C2—S1110.36 (16)O5—C16—O4123.4 (2)
O1—C3—N1123.4 (2)O5—C16—C17126.0 (2)
O1—C3—C2126.8 (2)O4—C16—C17110.6 (2)
N1—C3—C2109.76 (19)C16—C17—H17A109.5
O3—C4—H4A109.5C16—C17—H17B109.5
O3—C4—H4B109.5H17A—C17—H17B109.5
H4A—C4—H4B109.5C16—C17—H17C109.5
O3—C4—H4C109.5H17A—C17—H17C109.5
H4A—C4—H4C109.5H17B—C17—H17C109.5
H4B—C4—H4C109.5C2—C18—C19129.8 (2)
N1—C5—C6108.19 (17)C2—C18—H18115.1
N1—C5—C11109.45 (16)C19—C18—H18115.1
C6—C5—C11113.06 (18)C24—C19—C20116.4 (2)
N1—C5—H5108.7C24—C19—C18120.8 (2)
C6—C5—H5108.7C20—C19—C18122.8 (2)
C11—C5—H5108.7C21—C20—C19121.8 (2)
C7—C6—C8126.3 (2)C21—C20—H20119.1
C7—C6—C5122.34 (19)C19—C20—H20119.1
C8—C6—C5111.35 (19)C22—C21—C20119.9 (2)
C6—C7—N2121.6 (2)C22—C21—H21120.1
C6—C7—C1127.3 (2)C20—C21—H21120.1
N2—C7—C1111.08 (19)C23—C22—C21120.1 (2)
O2—C8—O3123.7 (2)C23—C22—H22119.9
O2—C8—C6122.5 (2)C21—C22—H22119.9
O3—C8—C6113.8 (2)C22—C23—C24119.6 (3)
N2—C9—N1126.87 (19)C22—C23—H23120.2
N2—C9—S1121.52 (17)C24—C23—H23120.2
N1—C9—S1111.59 (16)C23—C24—C19122.2 (2)
C15—C10—C11120.8 (2)C23—C24—Br1117.3 (2)
C15—C10—H10119.6C19—C24—Br1120.52 (18)
C11—C10—H10119.6C9—N1—C3116.59 (18)
C12—C11—C10119.3 (2)C9—N1—C5120.26 (18)
C12—C11—C5120.8 (2)C3—N1—C5122.05 (18)
C10—C11—C5119.8 (2)C9—N2—C7116.48 (19)
C11—C12—C13120.4 (2)C8—O3—C4115.0 (2)
C11—C12—H12119.8C16—O4—C14118.97 (19)
C13—C12—H12119.8C9—S1—C291.67 (11)
C14—C13—C12119.1 (2)
C18—C2—C3—O11.9 (4)C19—C20—C21—C220.3 (4)
S1—C2—C3—O1179.35 (19)C20—C21—C22—C230.5 (4)
C18—C2—C3—N1176.6 (2)C21—C22—C23—C240.7 (5)
S1—C2—C3—N10.9 (2)C22—C23—C24—C190.2 (5)
N1—C5—C6—C716.1 (3)C22—C23—C24—Br1179.8 (2)
C11—C5—C6—C7105.3 (2)C20—C19—C24—C230.5 (4)
N1—C5—C6—C8162.92 (17)C18—C19—C24—C23179.5 (3)
C11—C5—C6—C875.7 (2)C20—C19—C24—Br1179.49 (17)
C8—C6—C7—N2178.3 (2)C18—C19—C24—Br10.4 (3)
C5—C6—C7—N20.6 (3)N2—C9—N1—C3176.5 (2)
C8—C6—C7—C11.2 (4)S1—C9—N1—C32.1 (2)
C5—C6—C7—C1179.9 (2)N2—C9—N1—C515.3 (3)
C7—C6—C8—O2168.1 (2)S1—C9—N1—C5166.10 (15)
C5—C6—C8—O210.9 (3)O1—C3—N1—C9179.5 (2)
C7—C6—C8—O313.6 (3)C2—C3—N1—C92.0 (3)
C5—C6—C8—O3167.38 (18)O1—C3—N1—C512.5 (3)
C15—C10—C11—C120.2 (3)C2—C3—N1—C5166.05 (18)
C15—C10—C11—C5177.5 (2)C6—C5—N1—C922.8 (3)
N1—C5—C11—C12102.4 (2)C11—C5—N1—C9100.8 (2)
C6—C5—C11—C12137.0 (2)C6—C5—N1—C3169.64 (18)
N1—C5—C11—C1075.3 (2)C11—C5—N1—C366.8 (2)
C6—C5—C11—C1045.4 (3)N1—C9—N2—C72.9 (3)
C10—C11—C12—C130.1 (3)S1—C9—N2—C7175.63 (15)
C5—C11—C12—C13177.53 (19)C6—C7—N2—C910.2 (3)
C11—C12—C13—C140.5 (3)C1—C7—N2—C9169.4 (2)
C12—C13—C14—C151.0 (3)O2—C8—O3—C44.2 (3)
C12—C13—C14—O4177.54 (19)C6—C8—O3—C4177.6 (2)
C13—C14—C15—C101.0 (3)O5—C16—O4—C141.3 (4)
O4—C14—C15—C10177.5 (2)C17—C16—O4—C14177.5 (2)
C11—C10—C15—C140.6 (3)C15—C14—O4—C1663.7 (3)
C3—C2—C18—C19176.1 (2)C13—C14—O4—C16119.7 (2)
S1—C2—C18—C190.8 (4)N2—C9—S1—C2177.4 (2)
C2—C18—C19—C24163.0 (2)N1—C9—S1—C21.26 (17)
C2—C18—C19—C2018.0 (4)C18—C2—S1—C9177.3 (2)
C24—C19—C20—C210.7 (3)C3—C2—S1—C90.18 (16)
C18—C19—C20—C21179.7 (2)
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C5–C7/C9/N1/N2 ring.
D—H···AD—HH···AD···AD—H···A
C13—H13···O1i0.932.603.343 (4)138
C10—H10···Cgii0.932.613.513 (4)147
Symmetry codes: (i) x+1, y+2, z+1; (ii) x1, y1, z1.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C5–C7/C9/N1/N2 ring.
D—H···AD—HH···AD···AD—H···A
C13—H13···O1i0.9302.603.343 (4)138
C10—H10···Cgii0.9302.613.513 (4)147
Symmetry codes: (i) x+1, y+2, z+1; (ii) x1, y1, z1.
Acknowledgements top

NSB is thankful to the University Grants Commission (UGC), India, for financial assistance.

references
References top

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