organic compounds
2-[N-(4-Methoxyphenyl)acetamido]-1,3-thiazol-4-yl acetate
aDepartment of Pharmaceutical, Organic and Bioorganic Chemistry, Danylo Halytsky Lviv National Medical University, Pekarska 69, Lviv, 79010, Ukraine, bDepartment of Organic Chemistry, Poznan University of Medical Sciences, ul. Grunwaldzka 6, 60-780 Poznań, Poland, and cFaculty of Pharmacy, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, ul. A. Jurasza 2, 85-089 Bydgoszcz, Poland
*Correspondence e-mail: akgzella@ump.edu.pl
The structural analysis of the title compound, C14H14N2O4S, particularly the presence of an acetyl group at the exocyclic N atom and the C(H)—C(O2CMe)—N acetoxy group in the thiazole ring, may indicate that one of the starting materials, i.e. 2-(4-methoxyanilino)-1,3-thiazol-4(5H)-one, exists in the reaction mixture, at least partially, as a tautomer with an exocyclic amine N atom and an enol group. The acetoxy and acetyl groups deviate from the thiazole plane by 69.17 (6) and 7.25 (19)°, respectively. The thiazole and benzene rings form a dihedral angle of 73.50 (4)°. In the crystal, centrosymmetrically related molecules are connected into dimeric aggregates via C—H⋯O interactions.
Related literature
For the biological activity of 2-aryl(heteryl)aminothiazol-4-one derivatives, see: Ates et al. (2000); Eleftheriou et al. (2012); Eriksson et al. (2007); Lesyk & Zimenkovsky (2004); Lesyk et al. (2003, 2011); Rout & Mahapatra (1955); Subtel'na et al. (2010). For prototropic studies, see: Lesyk et al. (2003); Subtel'na et al. (2010). For bond-length data, see: Allen et al. (1987). For a related structural study, see: Horishny et al. (2013).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Agilent, 2011); cell CrysAlis PRO; data reduction: CrysAlis PRO; 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: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).
Supporting information
10.1107/S1600536813004236/tk5195sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813004236/tk5195Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813004236/tk5195Isup3.cml
2-(4-Methoxyanilino)thiazol-4-one in the medium of acetic anhydride was refluxed for 2 h. The obtained solution was evaporated in vacuum and the residue was recrystallized twice from benzene–hexane (1:1) mixtures.
All H atoms were located into the idealized positions and were refined within the riding model approximation: Cmethyl—H = 0.96 Å, C(sp2)—H = 0.93 Å; Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C) for methyl H. The methyl groups were refined as rigid groups which were allowed to rotate.
Data collection: CrysAlis PRO (Agilent, 2011); cell
CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); 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: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).C14H14N2O4S | Z = 2 |
Mr = 306.33 | F(000) = 320 |
Triclinic, P1 | Dx = 1.435 Mg m−3 |
Hall symbol: -P 1 | Melting point = 399–401 K |
a = 8.9445 (5) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 9.5736 (8) Å | Cell parameters from 5310 reflections |
c = 9.9078 (9) Å | θ = 2.3–29.1° |
α = 115.509 (9)° | µ = 0.25 mm−1 |
β = 93.381 (6)° | T = 130 K |
γ = 108.144 (6)° | Block, yellow |
V = 708.95 (10) Å3 | 0.50 × 0.50 × 0.10 mm |
Agilent Xcalibur Atlas diffractometer | 3445 independent reflections |
Radiation source: fine-focus sealed tube | 3075 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
Detector resolution: 10.3088 pixels mm-1 | θmax = 29.1°, θmin = 2.3° |
ω scans | h = −11→11 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011) | k = −13→12 |
Tmin = 0.860, Tmax = 1.000 | l = −12→13 |
12469 measured reflections |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.095 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.045P)2 + 0.2987P] where P = (Fo2 + 2Fc2)/3 |
3445 reflections | (Δ/σ)max < 0.001 |
193 parameters | Δρmax = 0.37 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
C14H14N2O4S | γ = 108.144 (6)° |
Mr = 306.33 | V = 708.95 (10) Å3 |
Triclinic, P1 | Z = 2 |
a = 8.9445 (5) Å | Mo Kα radiation |
b = 9.5736 (8) Å | µ = 0.25 mm−1 |
c = 9.9078 (9) Å | T = 130 K |
α = 115.509 (9)° | 0.50 × 0.50 × 0.10 mm |
β = 93.381 (6)° |
Agilent Xcalibur Atlas diffractometer | 3445 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011) | 3075 reflections with I > 2σ(I) |
Tmin = 0.860, Tmax = 1.000 | Rint = 0.022 |
12469 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.095 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.37 e Å−3 |
3445 reflections | Δρmin = −0.27 e Å−3 |
193 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 | ||
S1 | −0.09020 (4) | 0.14762 (4) | 0.45516 (4) | 0.02269 (10) | |
C2 | 0.03052 (15) | 0.08180 (16) | 0.32947 (14) | 0.0177 (2) | |
N3 | 0.16077 (13) | 0.19958 (13) | 0.34043 (12) | 0.0191 (2) | |
C4 | 0.16774 (16) | 0.34906 (16) | 0.45435 (15) | 0.0215 (3) | |
C5 | 0.04751 (17) | 0.34910 (17) | 0.52956 (16) | 0.0249 (3) | |
H5 | 0.0399 | 0.4428 | 0.6090 | 0.030* | |
N6 | −0.00495 (12) | −0.08552 (13) | 0.22511 (12) | 0.0182 (2) | |
C7 | −0.14419 (16) | −0.20995 (17) | 0.21360 (16) | 0.0233 (3) | |
O8 | −0.24272 (12) | −0.17289 (13) | 0.28765 (13) | 0.0308 (2) | |
C9 | −0.16476 (18) | −0.38706 (18) | 0.10871 (18) | 0.0305 (3) | |
H9A | −0.2535 | −0.4615 | 0.1245 | 0.046* | |
H9B | −0.0678 | −0.4040 | 0.1305 | 0.046* | |
H9C | −0.1861 | −0.4089 | 0.0040 | 0.046* | |
C10 | 0.11162 (15) | −0.12397 (15) | 0.13403 (14) | 0.0182 (2) | |
C11 | 0.25487 (16) | −0.11824 (17) | 0.20057 (15) | 0.0220 (3) | |
H11 | 0.2770 | −0.0887 | 0.3042 | 0.026* | |
C12 | 0.36650 (16) | −0.15662 (17) | 0.11261 (16) | 0.0237 (3) | |
H12 | 0.4633 | −0.1527 | 0.1569 | 0.028* | |
C13 | 0.33070 (16) | −0.20089 (16) | −0.04265 (16) | 0.0229 (3) | |
C14 | 0.18573 (17) | −0.20726 (17) | −0.10887 (15) | 0.0240 (3) | |
H14 | 0.1623 | −0.2383 | −0.2128 | 0.029* | |
C15 | 0.07619 (16) | −0.16761 (16) | −0.02071 (15) | 0.0213 (3) | |
H15 | −0.0201 | −0.1701 | −0.0645 | 0.026* | |
O16 | 0.42891 (13) | −0.24239 (14) | −0.14095 (12) | 0.0321 (2) | |
C17 | 0.57663 (19) | −0.2456 (2) | −0.0825 (2) | 0.0358 (4) | |
H17A | 0.6389 | −0.1390 | 0.0039 | 0.054* | |
H17B | 0.6368 | −0.2696 | −0.1611 | 0.054* | |
H17C | 0.5537 | −0.3304 | −0.0509 | 0.054* | |
O18 | 0.30433 (12) | 0.49009 (12) | 0.49350 (11) | 0.0263 (2) | |
C19 | 0.31110 (16) | 0.56737 (17) | 0.40442 (16) | 0.0238 (3) | |
O20 | 0.20654 (12) | 0.51567 (14) | 0.29430 (12) | 0.0311 (2) | |
C21 | 0.46079 (18) | 0.7203 (2) | 0.4657 (2) | 0.0372 (4) | |
H21A | 0.5421 | 0.6945 | 0.4116 | 0.056* | |
H21B | 0.4991 | 0.7596 | 0.5730 | 0.056* | |
H21C | 0.4376 | 0.8053 | 0.4520 | 0.056* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.02568 (18) | 0.02852 (19) | 0.02403 (18) | 0.01508 (14) | 0.01369 (13) | 0.01672 (15) |
C2 | 0.0191 (6) | 0.0226 (6) | 0.0167 (6) | 0.0101 (5) | 0.0062 (4) | 0.0118 (5) |
N3 | 0.0194 (5) | 0.0210 (5) | 0.0186 (5) | 0.0081 (4) | 0.0053 (4) | 0.0102 (4) |
C4 | 0.0252 (6) | 0.0201 (6) | 0.0195 (6) | 0.0085 (5) | 0.0027 (5) | 0.0098 (5) |
C5 | 0.0336 (7) | 0.0255 (7) | 0.0211 (6) | 0.0165 (6) | 0.0092 (5) | 0.0117 (6) |
N6 | 0.0182 (5) | 0.0195 (5) | 0.0183 (5) | 0.0067 (4) | 0.0064 (4) | 0.0100 (4) |
C7 | 0.0215 (6) | 0.0257 (7) | 0.0246 (7) | 0.0057 (5) | 0.0047 (5) | 0.0157 (6) |
O8 | 0.0236 (5) | 0.0334 (6) | 0.0390 (6) | 0.0084 (4) | 0.0141 (4) | 0.0207 (5) |
C9 | 0.0312 (7) | 0.0221 (7) | 0.0329 (8) | 0.0028 (6) | 0.0072 (6) | 0.0135 (6) |
C10 | 0.0212 (6) | 0.0159 (5) | 0.0181 (6) | 0.0069 (5) | 0.0075 (5) | 0.0084 (5) |
C11 | 0.0238 (6) | 0.0241 (6) | 0.0188 (6) | 0.0087 (5) | 0.0057 (5) | 0.0110 (5) |
C12 | 0.0208 (6) | 0.0247 (6) | 0.0258 (7) | 0.0086 (5) | 0.0051 (5) | 0.0122 (6) |
C13 | 0.0286 (7) | 0.0173 (6) | 0.0235 (7) | 0.0086 (5) | 0.0122 (5) | 0.0095 (5) |
C14 | 0.0343 (7) | 0.0217 (6) | 0.0158 (6) | 0.0108 (5) | 0.0068 (5) | 0.0084 (5) |
C15 | 0.0249 (6) | 0.0200 (6) | 0.0196 (6) | 0.0085 (5) | 0.0036 (5) | 0.0098 (5) |
O16 | 0.0367 (6) | 0.0362 (6) | 0.0288 (5) | 0.0192 (5) | 0.0182 (4) | 0.0148 (5) |
C17 | 0.0318 (8) | 0.0345 (8) | 0.0471 (10) | 0.0178 (7) | 0.0216 (7) | 0.0192 (7) |
O18 | 0.0276 (5) | 0.0202 (5) | 0.0259 (5) | 0.0053 (4) | 0.0000 (4) | 0.0097 (4) |
C19 | 0.0227 (6) | 0.0233 (6) | 0.0278 (7) | 0.0112 (5) | 0.0095 (5) | 0.0120 (6) |
O20 | 0.0288 (5) | 0.0357 (6) | 0.0291 (5) | 0.0071 (4) | 0.0047 (4) | 0.0194 (5) |
C21 | 0.0253 (7) | 0.0317 (8) | 0.0537 (10) | 0.0046 (6) | 0.0024 (7) | 0.0245 (8) |
S1—C5 | 1.7233 (15) | C11—H11 | 0.9300 |
S1—C2 | 1.7379 (12) | C12—C13 | 1.3944 (19) |
C2—N3 | 1.3046 (16) | C12—H12 | 0.9300 |
C2—N6 | 1.3979 (17) | C13—O16 | 1.3649 (16) |
N3—C4 | 1.3678 (17) | C13—C14 | 1.390 (2) |
C4—C5 | 1.3439 (19) | C14—C15 | 1.3835 (18) |
C4—O18 | 1.3899 (16) | C14—H14 | 0.9300 |
C5—H5 | 0.9300 | C15—H15 | 0.9300 |
N6—C7 | 1.3876 (16) | O16—C17 | 1.4258 (19) |
N6—C10 | 1.4494 (15) | C17—H17A | 0.9600 |
C7—O8 | 1.2196 (17) | C17—H17B | 0.9600 |
C7—C9 | 1.501 (2) | C17—H17C | 0.9600 |
C9—H9A | 0.9600 | O18—C19 | 1.3677 (17) |
C9—H9B | 0.9600 | C19—O20 | 1.1984 (17) |
C9—H9C | 0.9600 | C19—C21 | 1.491 (2) |
C10—C11 | 1.3801 (18) | C21—H21A | 0.9600 |
C10—C15 | 1.3907 (18) | C21—H21B | 0.9600 |
C11—C12 | 1.3953 (18) | C21—H21C | 0.9600 |
C5—S1—C2 | 88.70 (6) | C13—C12—C11 | 119.01 (12) |
N3—C2—N6 | 121.23 (11) | C13—C12—H12 | 120.5 |
N3—C2—S1 | 115.46 (10) | C11—C12—H12 | 120.5 |
N6—C2—S1 | 123.30 (9) | O16—C13—C14 | 114.88 (12) |
C2—N3—C4 | 108.79 (11) | O16—C13—C12 | 124.64 (13) |
C5—C4—N3 | 118.01 (12) | C14—C13—C12 | 120.48 (12) |
C5—C4—O18 | 123.64 (12) | C15—C14—C13 | 120.23 (12) |
N3—C4—O18 | 118.17 (11) | C15—C14—H14 | 119.9 |
C4—C5—S1 | 109.03 (10) | C13—C14—H14 | 119.9 |
C4—C5—H5 | 125.5 | C14—C15—C10 | 119.31 (12) |
S1—C5—H5 | 125.5 | C14—C15—H15 | 120.3 |
C7—N6—C2 | 120.87 (11) | C10—C15—H15 | 120.3 |
C7—N6—C10 | 121.59 (11) | C13—O16—C17 | 117.97 (12) |
C2—N6—C10 | 117.51 (10) | O16—C17—H17A | 109.5 |
O8—C7—N6 | 119.90 (12) | O16—C17—H17B | 109.5 |
O8—C7—C9 | 123.04 (12) | H17A—C17—H17B | 109.5 |
N6—C7—C9 | 117.05 (12) | O16—C17—H17C | 109.5 |
C7—C9—H9A | 109.5 | H17A—C17—H17C | 109.5 |
C7—C9—H9B | 109.5 | H17B—C17—H17C | 109.5 |
H9A—C9—H9B | 109.5 | C19—O18—C4 | 117.42 (10) |
C7—C9—H9C | 109.5 | O20—C19—O18 | 122.46 (12) |
H9A—C9—H9C | 109.5 | O20—C19—C21 | 126.78 (13) |
H9B—C9—H9C | 109.5 | O18—C19—C21 | 110.75 (12) |
C11—C10—C15 | 120.86 (12) | C19—C21—H21A | 109.5 |
C11—C10—N6 | 120.11 (11) | C19—C21—H21B | 109.5 |
C15—C10—N6 | 119.03 (11) | H21A—C21—H21B | 109.5 |
C10—C11—C12 | 120.11 (12) | C19—C21—H21C | 109.5 |
C10—C11—H11 | 119.9 | H21A—C21—H21C | 109.5 |
C12—C11—H11 | 119.9 | H21B—C21—H21C | 109.5 |
C5—S1—C2—N3 | −0.81 (10) | C7—N6—C10—C15 | 75.64 (16) |
C5—S1—C2—N6 | 177.79 (11) | C2—N6—C10—C15 | −106.51 (13) |
N6—C2—N3—C4 | −177.87 (11) | C15—C10—C11—C12 | −0.1 (2) |
S1—C2—N3—C4 | 0.76 (13) | N6—C10—C11—C12 | 179.45 (11) |
C2—N3—C4—C5 | −0.29 (16) | C10—C11—C12—C13 | −0.1 (2) |
C2—N3—C4—O18 | 174.95 (10) | C11—C12—C13—O16 | −179.44 (12) |
N3—C4—C5—S1 | −0.30 (15) | C11—C12—C13—C14 | −0.2 (2) |
O18—C4—C5—S1 | −175.25 (10) | O16—C13—C14—C15 | −179.91 (12) |
C2—S1—C5—C4 | 0.58 (10) | C12—C13—C14—C15 | 0.8 (2) |
N3—C2—N6—C7 | −179.65 (11) | C13—C14—C15—C10 | −1.00 (19) |
S1—C2—N6—C7 | 1.83 (17) | C11—C10—C15—C14 | 0.63 (19) |
N3—C2—N6—C10 | 2.48 (17) | N6—C10—C15—C14 | −178.89 (11) |
S1—C2—N6—C10 | −176.04 (9) | C14—C13—O16—C17 | −177.34 (12) |
C2—N6—C7—O8 | 4.96 (19) | C12—C13—O16—C17 | 1.9 (2) |
C10—N6—C7—O8 | −177.26 (12) | C5—C4—O18—C19 | −102.83 (15) |
C2—N6—C7—C9 | −174.65 (12) | N3—C4—O18—C19 | 82.22 (15) |
C10—N6—C7—C9 | 3.14 (18) | C4—O18—C19—O20 | −1.67 (19) |
C7—N6—C10—C11 | −103.88 (14) | C4—O18—C19—C21 | 177.30 (12) |
C2—N6—C10—C11 | 73.97 (15) |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O20i | 0.93 | 2.53 | 3.200 (2) | 129 |
Symmetry code: (i) −x, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C14H14N2O4S |
Mr | 306.33 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 130 |
a, b, c (Å) | 8.9445 (5), 9.5736 (8), 9.9078 (9) |
α, β, γ (°) | 115.509 (9), 93.381 (6), 108.144 (6) |
V (Å3) | 708.95 (10) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.25 |
Crystal size (mm) | 0.50 × 0.50 × 0.10 |
Data collection | |
Diffractometer | Agilent Xcalibur Atlas diffractometer |
Absorption correction | Multi-scan (CrysAlis PRO; Agilent, 2011) |
Tmin, Tmax | 0.860, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12469, 3445, 3075 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.684 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.095, 1.06 |
No. of reflections | 3445 |
No. of parameters | 193 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.37, −0.27 |
Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O20i | 0.93 | 2.53 | 3.200 (2) | 129 |
Symmetry code: (i) −x, −y+1, −z+1. |
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Subtel'na, I., Atamanyuk, D., Szymańska, E., Kieć-Kononowicz, K., Zimenkovsky, B., Vasylenko, O., Gzella, A. & Lesyk, R. (2010). Bioorg. Med. Chem. 18, 5090–5102. Web of Science CAS PubMed Google Scholar
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Significant popularity of thiazolidine scaffolds in drug design is grounded on the broad spectrum of biological activity of their derivatives. Among thiazolidine derivatives the group of 2-aryl(heteryl)aminothiazol-4-one derivatives is one of the most promising (Lesyk & Zimenkovsky, 2004; Lesyk et al., 2011). 2-Aryl(heteryl)aminothiazol-4-one activities covers antibacterial (Ates et al., 2000), antifungal (Rout & Mahapatra, 1955), anti-inflammatory (Lesyk et al., 2003; Eleftheriou et al., 2012) and anticancer activities (Subtel'na et al., 2010; Eriksson et al., 2007). Moreover, literature reports indicate existence of prototropic tautomeric forms of 3-unsubstituted 2-aryl(heteryl)aminothiazol-4-ones both in solutions and solid phase which can be of significant importance for biological activity (Lesyk et al., 2003; Subtel'na et al., 2010). Dictated by these observations, the aim of the presented work was synthesis of the compound (I) as starting substance for further design of new biologically active compounds.
The investigations on the structure of the title compound, a product of the reaction of 2-(4-methoxyanilino)-1,3-thiazol-4-one with acetyl anhydride, showed the presence of an acetoxy group at C4 and an acetyl functionality at N6 (Fig. 1). Similar observations were made for the product obtained by the identical method from 2-(2,4-dimethoxyanilino)-1,3-thiazol-4-one. The presence of the C4 acetoxy and N6 acetyl groups in the structure of compound (I) and 2-[N-(2,4-dimethoxyphenyl)acetamido]-1,3-thiazol-4-yl acetate (Horishny et al., 2013) may indicate that the starting materials, i.e. 2-(4-methoxyanilino)-1,3-thiazol-4-one and 2-(2,4-dimethoxyanilino)-1,3-thiazol-4-one, exist in the reaction mixture at least partially as tautomers with an exocyclic amine nitrogen and an enol moiety (H—)C5═C4—OH within the five-membered heterocyclic ring.
The C4 acetoxy group and N6 acetyl functionality are oriented differently in relation to the planar thiazole ring. The first one forms a dihedral angle of 79.22 (5)° with the mean plane of this ring whereas the second one is tilted only slightly [dihedral angle: 7.25 (19)°] (Fig. 1).
Both the C7═O8 carbonyl group relative to the C2—N6 bond and the C21═ O22 carbonyl group in relation to the C4—O20 bond have the same synperiplanar conformation. The torsional angles C2—N6—C7—O8 and C4—O18—C19—O20 are 4.96 (19) and -1.67 (19)°, respectively. The C13 methoxy group is approximately coplanar with the phenyl ring – the torsion angle is 1.9 (2)°. The flat phenyl and thiazole rings form a dihedral angle of 73.50 (4)°.
The bond lengths and angles in compound (I) are similar to those observed in 2-[N-(2,4-dimethoxyphenyl)acetamido]-1,3-thiazol-4-yl acetate (Horishny et al., 2013). The N6—C7 distance [1.3876 (16) Å] is longer (by about 8σ) than the normal (O═)C—N tertiary amide distance [1.346 (5) Å, Allen et al., 1987].
In the crystal structure, the molecules of (I) are connected by the C5—H5···O21i hydrogen bonds into centrosymmetric dimers (Table 1, Fig. 2).