Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807034976/rz2158sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807034976/rz2158Isup2.hkl |
CCDC reference: 657828
To a stirred solution of 6-(2,6-dichlorobenzyl)-5-ethyl-2,3-dihydro-2-thioxopyrimidin-4(1H)-one (1 g, 3.17 mmol) in anhydrous DMF (18 ml) was added K2CO3 (0.53 g, 3.84 mmol) under a nitrogen atmosphere. The mixture was stirred at 298 K for 20 min, then 1-(bromomethyl)-4-methoxybenzene (0.60 g, 3.83 mmol) was added, and the reaction mixture was stirred at 298 K for 28 h. The reaction mixture was poured into cold H2O (100 ml), the resulting precipitate was collected by filtration, washed with water and recrystallized from butan-2-one (yield: 46%; m.p. 504.2–504.5 K). Single cystals of the title compound suitable for X-ray diffraction were grown by slow evaporation of a DMF solution. The product was characterized by IR, MS, 1H NMR and 13C NMR.
The H atom bound to N1 was located in a difference Fourier map and refined with a distance restraint of 0.86 (1) Å. All other H atoms were placed in geometrically idealized position and constrained to ride on their parent atoms, with C—H distances in the range 0.93–0.98 Å, and with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for other H atoms. Methyl groups were allowed to rotate freely about the C—C bond.
As part of an ongoing research work aimed at developing potent HIV-1 inhibitors, we have recently focused our attention on the structural modifications of dihydroalkoxybenzyloxopyrimidines (DABOs), one of the most interesting and representative classes of non-nucleoside reverse transcriptase inhibitors (NNRTIs). We have synthesized a series of 2-arylalkylsulfur-substituted DABOs analogues, including the title compound, (I), as potential HIV-1 inhibitors. According to the possible delocalization of the C═N double bond in the pyrimidine ring, compound (I) could theoretically exist in three different tautomeric forms: the 1H-, the 3H-, and the aromatic form (Fig. 1). While NMR spectroscopy strongly indicated that the title compound adopted the 3H-tautomeric form, confirmations was sought using X-ray crystallography.
In the structure of (I), the carbonyl C—O bond length is 1.245 (4) Å, which is not significantly different from the value of 1.242 (3) Å found in 2-(cyclopentylsulfanyl)-6-(1-naphthoyl)-pyrimidin-4(3H)-one (Ji et al., 2006). Meanwhile, the lengths of C9—N1 and C9—N2 bonds are 1.344 (4) Å and 1.299 (4) Å, respectively. These values confirm that the title compound adopts the 3H-tautomeric form in the solid state (Fig. 2).
In the crystal structure, centrosymmetric dimers are formed by pairs of N1—H1···O2ii hydrogen bonds [symmetry code: (ii) -x, -y + 2, -z]. These dimers are further linked by weak C—H···O interactions (Table 1, Fig. 3).
For the crystal structure of a related pyrimidin-4(3H)-one, see: Ji et al. (2006).
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL.
C21H20Cl2N2O2S | F(000) = 904 |
Mr = 435.35 | Dx = 1.334 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 946 reflections |
a = 10.037 (3) Å | θ = 2.4–19.2° |
b = 17.264 (5) Å | µ = 0.42 mm−1 |
c = 13.006 (4) Å | T = 293 K |
β = 105.901 (5)° | Block, colourless |
V = 2167.4 (12) Å3 | 0.20 × 0.20 × 0.15 mm |
Z = 4 |
Bruker SMART APEX CCD area-detector diffractometer | 4733 independent reflections |
Radiation source: fine-focus sealed tube | 2050 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.050 |
φ and ω scans | θmax = 27.2°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −12→12 |
Tmin = 0.922, Tmax = 0.940 | k = −21→21 |
10682 measured reflections | l = −14→16 |
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)] = 0.069 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.222 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.87 | w = 1/[σ2(Fo2) + (0.1246P)2] where P = (Fo2 + 2Fc2)/3 |
4733 reflections | (Δ/σ)max < 0.001 |
259 parameters | Δρmax = 0.79 e Å−3 |
1 restraint | Δρmin = −0.36 e Å−3 |
C21H20Cl2N2O2S | V = 2167.4 (12) Å3 |
Mr = 435.35 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.037 (3) Å | µ = 0.42 mm−1 |
b = 17.264 (5) Å | T = 293 K |
c = 13.006 (4) Å | 0.20 × 0.20 × 0.15 mm |
β = 105.901 (5)° |
Bruker SMART APEX CCD area-detector diffractometer | 4733 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2050 reflections with I > 2σ(I) |
Tmin = 0.922, Tmax = 0.940 | Rint = 0.050 |
10682 measured reflections |
R[F2 > 2σ(F2)] = 0.069 | 1 restraint |
wR(F2) = 0.222 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.87 | Δρmax = 0.79 e Å−3 |
4733 reflections | Δρmin = −0.36 e Å−3 |
259 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.4124 (2) | 0.63842 (15) | −0.0284 (2) | 0.2158 (13) | |
Cl2 | 0.1444 (2) | 0.68614 (13) | 0.26805 (15) | 0.1606 (8) | |
N1 | 0.1198 (3) | 0.92035 (15) | 0.0294 (2) | 0.0535 (7) | |
N2 | 0.2527 (3) | 0.80811 (15) | 0.0714 (2) | 0.0565 (7) | |
O1 | 1.0343 (3) | 1.00550 (19) | 0.3657 (2) | 0.0954 (10) | |
O2 | −0.1101 (2) | 0.92001 (13) | −0.05248 (19) | 0.0621 (7) | |
S1 | 0.38515 (10) | 0.94244 (5) | 0.11803 (10) | 0.0775 (4) | |
C1 | 1.1372 (5) | 1.0113 (4) | 0.3105 (4) | 0.145 (3) | |
H1A | 1.1553 | 0.9609 | 0.2861 | 0.217* | |
H1B | 1.2207 | 1.0318 | 0.3576 | 0.217* | |
H1C | 1.1055 | 1.0452 | 0.2502 | 0.217* | |
C2 | 0.9086 (4) | 0.9743 (2) | 0.3126 (3) | 0.0639 (10) | |
C3 | 0.8719 (4) | 0.9551 (3) | 0.2074 (3) | 0.0863 (13) | |
H3 | 0.9330 | 0.9639 | 0.1662 | 0.104* | |
C4 | 0.7439 (4) | 0.9227 (3) | 0.1616 (3) | 0.0837 (13) | |
H4 | 0.7197 | 0.9098 | 0.0894 | 0.100* | |
C5 | 0.6523 (4) | 0.9091 (2) | 0.2194 (3) | 0.0645 (10) | |
C6 | 0.6893 (4) | 0.9330 (2) | 0.3243 (3) | 0.0652 (10) | |
H6 | 0.6264 | 0.9274 | 0.3646 | 0.078* | |
C7 | 0.8158 (4) | 0.9646 (2) | 0.3704 (3) | 0.0649 (10) | |
H7 | 0.8387 | 0.9796 | 0.4418 | 0.078* | |
C8 | 0.5162 (4) | 0.8701 (2) | 0.1694 (4) | 0.0775 (12) | |
H8A | 0.4898 | 0.8385 | 0.2222 | 0.093* | |
H8B | 0.5250 | 0.8366 | 0.1117 | 0.093* | |
C9 | 0.2405 (3) | 0.88306 (18) | 0.0689 (3) | 0.0545 (9) | |
C10 | −0.0018 (3) | 0.88240 (18) | −0.0153 (3) | 0.0519 (8) | |
C11 | 0.0061 (3) | 0.79882 (18) | −0.0140 (3) | 0.0529 (8) | |
C12 | 0.1330 (4) | 0.76667 (18) | 0.0313 (3) | 0.0523 (8) | |
C13 | −0.1228 (4) | 0.7540 (2) | −0.0637 (4) | 0.0788 (12) | |
H13A | −0.1796 | 0.7836 | −0.1230 | 0.095* | |
H13B | −0.0974 | 0.7061 | −0.0925 | 0.095* | |
C14 | −0.2057 (6) | 0.7353 (4) | 0.0102 (6) | 0.149 (3) | |
H14A | −0.1524 | 0.7031 | 0.0669 | 0.223* | |
H14B | −0.2881 | 0.7082 | −0.0277 | 0.223* | |
H14C | −0.2307 | 0.7823 | 0.0397 | 0.223* | |
C15 | 0.1547 (4) | 0.67980 (19) | 0.0402 (3) | 0.0621 (10) | |
H15A | 0.0758 | 0.6558 | 0.0569 | 0.074* | |
H15B | 0.1605 | 0.6595 | −0.0280 | 0.074* | |
C16 | 0.2846 (4) | 0.65926 (18) | 0.1253 (4) | 0.0668 (11) | |
C17 | 0.4062 (5) | 0.6412 (3) | 0.1025 (6) | 0.111 (2) | |
C18 | 0.5284 (9) | 0.6259 (5) | 0.1810 (11) | 0.179 (5) | |
H18 | 0.6096 | 0.6135 | 0.1633 | 0.215* | |
C19 | 0.5249 (13) | 0.6295 (5) | 0.2816 (12) | 0.202 (7) | |
H19 | 0.6067 | 0.6211 | 0.3350 | 0.242* | |
C20 | 0.4118 (10) | 0.6443 (4) | 0.3100 (7) | 0.168 (4) | |
H20 | 0.4137 | 0.6429 | 0.3818 | 0.202* | |
C21 | 0.2899 (6) | 0.6619 (3) | 0.2338 (5) | 0.1020 (16) | |
H1 | 0.112 (3) | 0.9696 (6) | 0.034 (2) | 0.052 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.178 (2) | 0.227 (2) | 0.307 (3) | −0.0219 (17) | 0.177 (2) | −0.089 (2) |
Cl2 | 0.1943 (19) | 0.1909 (17) | 0.1253 (14) | −0.0393 (15) | 0.0923 (13) | −0.0251 (12) |
N1 | 0.0436 (17) | 0.0386 (15) | 0.072 (2) | −0.0006 (12) | 0.0052 (14) | −0.0033 (14) |
N2 | 0.0438 (16) | 0.0430 (15) | 0.076 (2) | −0.0018 (12) | 0.0059 (14) | 0.0002 (14) |
O1 | 0.0632 (18) | 0.143 (3) | 0.0700 (18) | −0.0409 (18) | 0.0010 (14) | 0.0038 (18) |
O2 | 0.0438 (14) | 0.0544 (14) | 0.0789 (17) | 0.0035 (11) | 0.0011 (12) | −0.0029 (12) |
S1 | 0.0474 (6) | 0.0494 (5) | 0.1179 (9) | −0.0064 (4) | −0.0075 (5) | −0.0015 (5) |
C1 | 0.068 (3) | 0.265 (8) | 0.099 (4) | −0.071 (4) | 0.019 (3) | 0.014 (5) |
C2 | 0.050 (2) | 0.080 (2) | 0.054 (2) | −0.0116 (19) | 0.0014 (17) | 0.0017 (19) |
C3 | 0.063 (3) | 0.133 (4) | 0.063 (3) | −0.020 (3) | 0.019 (2) | −0.011 (3) |
C4 | 0.063 (3) | 0.124 (4) | 0.057 (2) | −0.011 (3) | 0.003 (2) | −0.022 (2) |
C5 | 0.043 (2) | 0.061 (2) | 0.081 (3) | −0.0001 (16) | 0.0021 (19) | −0.002 (2) |
C6 | 0.050 (2) | 0.072 (2) | 0.072 (3) | 0.0005 (18) | 0.0140 (19) | 0.009 (2) |
C7 | 0.063 (2) | 0.074 (2) | 0.053 (2) | −0.0082 (19) | 0.0096 (19) | −0.0013 (19) |
C8 | 0.046 (2) | 0.060 (2) | 0.109 (3) | 0.0023 (18) | −0.008 (2) | 0.000 (2) |
C9 | 0.045 (2) | 0.0464 (19) | 0.067 (2) | −0.0030 (15) | 0.0074 (16) | −0.0016 (16) |
C10 | 0.043 (2) | 0.0508 (19) | 0.059 (2) | −0.0008 (16) | 0.0085 (16) | −0.0040 (16) |
C11 | 0.0436 (19) | 0.0478 (18) | 0.064 (2) | −0.0055 (15) | 0.0087 (16) | −0.0037 (16) |
C12 | 0.052 (2) | 0.0465 (17) | 0.059 (2) | −0.0032 (15) | 0.0162 (17) | −0.0041 (16) |
C13 | 0.046 (2) | 0.057 (2) | 0.126 (4) | −0.0074 (18) | 0.010 (2) | −0.005 (2) |
C14 | 0.100 (5) | 0.131 (5) | 0.224 (8) | −0.029 (4) | 0.060 (5) | −0.040 (5) |
C15 | 0.061 (2) | 0.0440 (18) | 0.080 (3) | −0.0027 (16) | 0.019 (2) | −0.0100 (18) |
C16 | 0.054 (2) | 0.0361 (17) | 0.106 (3) | 0.0002 (16) | 0.014 (2) | 0.003 (2) |
C17 | 0.061 (3) | 0.065 (3) | 0.212 (7) | 0.006 (2) | 0.045 (4) | −0.005 (3) |
C18 | 0.072 (5) | 0.086 (4) | 0.365 (16) | 0.023 (3) | 0.038 (9) | 0.009 (8) |
C19 | 0.123 (8) | 0.083 (5) | 0.333 (17) | −0.010 (5) | −0.050 (12) | 0.077 (9) |
C20 | 0.168 (7) | 0.129 (6) | 0.151 (6) | −0.046 (6) | −0.050 (7) | 0.068 (5) |
C21 | 0.117 (4) | 0.079 (3) | 0.094 (4) | −0.025 (3) | 0.000 (3) | 0.022 (3) |
Cl1—C17 | 1.720 (7) | C7—H7 | 0.9300 |
Cl2—C21 | 1.692 (6) | C8—H8A | 0.9700 |
N1—C9 | 1.344 (4) | C8—H8B | 0.9700 |
N1—C10 | 1.366 (4) | C10—C11 | 1.445 (4) |
N1—H1 | 0.858 (10) | C11—C12 | 1.367 (5) |
N2—C9 | 1.299 (4) | C11—C13 | 1.494 (5) |
N2—C12 | 1.372 (4) | C12—C15 | 1.515 (5) |
O1—C2 | 1.372 (4) | C13—C14 | 1.470 (7) |
O1—C1 | 1.414 (5) | C13—H13A | 0.9700 |
O2—C10 | 1.245 (4) | C13—H13B | 0.9700 |
S1—C9 | 1.749 (3) | C14—H14A | 0.9600 |
S1—C8 | 1.804 (4) | C14—H14B | 0.9600 |
C1—H1A | 0.9600 | C14—H14C | 0.9600 |
C1—H1B | 0.9600 | C15—C16 | 1.504 (5) |
C1—H1C | 0.9600 | C15—H15A | 0.9700 |
C2—C3 | 1.357 (5) | C15—H15B | 0.9700 |
C2—C7 | 1.358 (5) | C16—C17 | 1.369 (6) |
C3—C4 | 1.378 (5) | C16—C21 | 1.398 (6) |
C3—H3 | 0.9300 | C17—C18 | 1.390 (11) |
C4—C5 | 1.358 (5) | C18—C19 | 1.320 (15) |
C4—H4 | 0.9300 | C18—H18 | 0.9300 |
C5—C6 | 1.375 (5) | C19—C20 | 1.311 (13) |
C5—C8 | 1.501 (5) | C19—H19 | 0.9300 |
C6—C7 | 1.361 (5) | C20—C21 | 1.381 (9) |
C6—H6 | 0.9300 | C20—H20 | 0.9300 |
C9—N1—C10 | 122.6 (3) | C12—C11—C10 | 116.9 (3) |
C9—N1—H1 | 123 (2) | C12—C11—C13 | 124.8 (3) |
C10—N1—H1 | 115 (2) | C10—C11—C13 | 118.3 (3) |
C9—N2—C12 | 116.3 (3) | C11—C12—N2 | 124.6 (3) |
C2—O1—C1 | 118.1 (3) | C11—C12—C15 | 122.1 (3) |
C9—S1—C8 | 100.25 (17) | N2—C12—C15 | 113.3 (3) |
O1—C1—H1A | 109.5 | C14—C13—C11 | 114.1 (4) |
O1—C1—H1B | 109.5 | C14—C13—H13A | 108.7 |
H1A—C1—H1B | 109.5 | C11—C13—H13A | 108.7 |
O1—C1—H1C | 109.5 | C14—C13—H13B | 108.7 |
H1A—C1—H1C | 109.5 | C11—C13—H13B | 108.7 |
H1B—C1—H1C | 109.5 | H13A—C13—H13B | 107.6 |
C3—C2—C7 | 119.4 (4) | C13—C14—H14A | 109.5 |
C3—C2—O1 | 124.1 (3) | C13—C14—H14B | 109.5 |
C7—C2—O1 | 116.5 (3) | H14A—C14—H14B | 109.5 |
C2—C3—C4 | 119.8 (4) | C13—C14—H14C | 109.5 |
C2—C3—H3 | 120.1 | H14A—C14—H14C | 109.5 |
C4—C3—H3 | 120.1 | H14B—C14—H14C | 109.5 |
C5—C4—C3 | 121.6 (4) | C16—C15—C12 | 111.5 (3) |
C5—C4—H4 | 119.2 | C16—C15—H15A | 109.3 |
C3—C4—H4 | 119.2 | C12—C15—H15A | 109.3 |
C4—C5—C6 | 117.2 (3) | C16—C15—H15B | 109.3 |
C4—C5—C8 | 120.7 (4) | C12—C15—H15B | 109.3 |
C6—C5—C8 | 122.1 (4) | H15A—C15—H15B | 108.0 |
C7—C6—C5 | 121.6 (3) | C17—C16—C21 | 115.9 (5) |
C7—C6—H6 | 119.2 | C17—C16—C15 | 122.6 (5) |
C5—C6—H6 | 119.2 | C21—C16—C15 | 121.4 (4) |
C2—C7—C6 | 120.3 (4) | C16—C17—C18 | 122.9 (7) |
C2—C7—H7 | 119.9 | C16—C17—Cl1 | 119.8 (5) |
C6—C7—H7 | 119.9 | C18—C17—Cl1 | 117.2 (6) |
C5—C8—S1 | 109.6 (3) | C19—C18—C17 | 117.5 (11) |
C5—C8—H8A | 109.8 | C19—C18—H18 | 121.3 |
S1—C8—H8A | 109.8 | C17—C18—H18 | 121.3 |
C5—C8—H8B | 109.8 | C20—C19—C18 | 123.2 (13) |
S1—C8—H8B | 109.8 | C20—C19—H19 | 118.4 |
H8A—C8—H8B | 108.2 | C18—C19—H19 | 118.4 |
N2—C9—N1 | 123.8 (3) | C19—C20—C21 | 120.5 (11) |
N2—C9—S1 | 120.7 (3) | C19—C20—H20 | 119.8 |
N1—C9—S1 | 115.5 (2) | C21—C20—H20 | 119.8 |
O2—C10—N1 | 119.9 (3) | C20—C21—C16 | 119.8 (7) |
O2—C10—C11 | 124.4 (3) | C20—C21—Cl2 | 121.7 (6) |
N1—C10—C11 | 115.7 (3) | C16—C21—Cl2 | 118.5 (4) |
C1—O1—C2—C3 | −6.3 (7) | C10—C11—C12—N2 | −2.6 (5) |
C1—O1—C2—C7 | 175.5 (5) | C13—C11—C12—N2 | 176.1 (3) |
C7—C2—C3—C4 | −3.1 (7) | C10—C11—C12—C15 | 178.5 (3) |
O1—C2—C3—C4 | 178.7 (4) | C13—C11—C12—C15 | −2.9 (5) |
C2—C3—C4—C5 | −0.1 (7) | C9—N2—C12—C11 | 2.8 (5) |
C3—C4—C5—C6 | 3.6 (7) | C9—N2—C12—C15 | −178.1 (3) |
C3—C4—C5—C8 | −177.0 (4) | C12—C11—C13—C14 | 91.8 (5) |
C4—C5—C6—C7 | −4.0 (6) | C10—C11—C13—C14 | −89.6 (5) |
C8—C5—C6—C7 | 176.6 (3) | C11—C12—C15—C16 | −159.2 (3) |
C3—C2—C7—C6 | 2.7 (6) | N2—C12—C15—C16 | 21.7 (4) |
O1—C2—C7—C6 | −179.0 (3) | C12—C15—C16—C17 | −99.4 (4) |
C5—C6—C7—C2 | 1.0 (6) | C12—C15—C16—C21 | 76.8 (4) |
C4—C5—C8—S1 | −92.8 (4) | C21—C16—C17—C18 | 0.4 (7) |
C6—C5—C8—S1 | 86.6 (4) | C15—C16—C17—C18 | 176.8 (5) |
C9—S1—C8—C5 | −178.5 (3) | C21—C16—C17—Cl1 | −178.6 (3) |
C12—N2—C9—N1 | −0.4 (5) | C15—C16—C17—Cl1 | −2.2 (5) |
C12—N2—C9—S1 | 179.8 (2) | C16—C17—C18—C19 | −0.3 (13) |
C10—N1—C9—N2 | −2.2 (5) | Cl1—C17—C18—C19 | 178.6 (8) |
C10—N1—C9—S1 | 177.7 (3) | C17—C18—C19—C20 | 2.2 (17) |
C8—S1—C9—N2 | −3.9 (4) | C18—C19—C20—C21 | −4.1 (16) |
C8—S1—C9—N1 | 176.2 (3) | C19—C20—C21—C16 | 4.0 (10) |
C9—N1—C10—O2 | −178.6 (3) | C19—C20—C21—Cl2 | −176.6 (7) |
C9—N1—C10—C11 | 2.3 (5) | C17—C16—C21—C20 | −2.2 (6) |
O2—C10—C11—C12 | −179.1 (3) | C15—C16—C21—C20 | −178.6 (4) |
N1—C10—C11—C12 | 0.0 (5) | C17—C16—C21—Cl2 | 178.4 (3) |
O2—C10—C11—C13 | 2.1 (5) | C15—C16—C21—Cl2 | 2.0 (5) |
N1—C10—C11—C13 | −178.8 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C15—H15B···Cl1 | 0.97 | 2.56 | 3.043 (4) | 111 |
C7—H7···O1i | 0.93 | 2.49 | 3.389 (5) | 162 |
N1—H1···O2ii | 0.86 (1) | 1.92 (1) | 2.777 (4) | 175 (3) |
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) −x, −y+2, −z. |
Experimental details
Crystal data | |
Chemical formula | C21H20Cl2N2O2S |
Mr | 435.35 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 10.037 (3), 17.264 (5), 13.006 (4) |
β (°) | 105.901 (5) |
V (Å3) | 2167.4 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.42 |
Crystal size (mm) | 0.20 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.922, 0.940 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10682, 4733, 2050 |
Rint | 0.050 |
(sin θ/λ)max (Å−1) | 0.642 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.069, 0.222, 0.87 |
No. of reflections | 4733 |
No. of parameters | 259 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.79, −0.36 |
Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2000), SHELXTL.
D—H···A | D—H | H···A | D···A | D—H···A |
C15—H15B···Cl1 | 0.97 | 2.56 | 3.043 (4) | 111.1 |
C7—H7···O1i | 0.93 | 2.49 | 3.389 (5) | 161.9 |
N1—H1···O2ii | 0.858 (10) | 1.921 (11) | 2.777 (4) | 175 (3) |
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) −x, −y+2, −z. |
As part of an ongoing research work aimed at developing potent HIV-1 inhibitors, we have recently focused our attention on the structural modifications of dihydroalkoxybenzyloxopyrimidines (DABOs), one of the most interesting and representative classes of non-nucleoside reverse transcriptase inhibitors (NNRTIs). We have synthesized a series of 2-arylalkylsulfur-substituted DABOs analogues, including the title compound, (I), as potential HIV-1 inhibitors. According to the possible delocalization of the C═N double bond in the pyrimidine ring, compound (I) could theoretically exist in three different tautomeric forms: the 1H-, the 3H-, and the aromatic form (Fig. 1). While NMR spectroscopy strongly indicated that the title compound adopted the 3H-tautomeric form, confirmations was sought using X-ray crystallography.
In the structure of (I), the carbonyl C—O bond length is 1.245 (4) Å, which is not significantly different from the value of 1.242 (3) Å found in 2-(cyclopentylsulfanyl)-6-(1-naphthoyl)-pyrimidin-4(3H)-one (Ji et al., 2006). Meanwhile, the lengths of C9—N1 and C9—N2 bonds are 1.344 (4) Å and 1.299 (4) Å, respectively. These values confirm that the title compound adopts the 3H-tautomeric form in the solid state (Fig. 2).
In the crystal structure, centrosymmetric dimers are formed by pairs of N1—H1···O2ii hydrogen bonds [symmetry code: (ii) -x, -y + 2, -z]. These dimers are further linked by weak C—H···O interactions (Table 1, Fig. 3).