Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803001302/cf6233sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803001302/cf6233Isup2.hkl |
CCDC reference: 204719
Key indicators
- Single-crystal X-ray study
- T = 150 K
- Mean (C-C) = 0.007 Å
- H-atom completeness 96%
- R factor = 0.096
- wR factor = 0.299
- Data-to-parameter ratio = 17.3
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
Alert Level C:
RFACR_01 Alert C The value of the weighted R factor is > 0.25 Weighted R factor given 0.299 RINTA_01 Alert C The value of Rint is greater than 0.10 Rint given 0.113 General Notes
FORMU_01 There is a discrepancy between the atom counts in the _chemical_formula_sum and the formula from the _atom_site* data. Atom count from _chemical_formula_sum:C15 H23 N2 O4 S1 Atom count from the _atom_site data: C15 H22 N2 O4 S1 CELLZ_01 From the CIF: _cell_formula_units_Z 8 From the CIF: _chemical_formula_sum C15 H23 N2 O4 S TEST: Compare cell contents of formula and atom_site data atom Z*formula cif sites diff C 120.00 120.00 0.00 H 184.00 176.00 8.00 N 16.00 16.00 0.00 O 32.00 32.00 0.00 S 8.00 8.00 0.00 Difference between formula and atom_site contents detected. WARNING: H atoms missing from atom site list. Is this intentional?
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
2 Alert Level C = Please check
The title compound was obtained from Key Organics Ltd and crystals were grown from iso-octane.
All H atoms were included in the refinement, at calculated positions, as riding models, with X—H set to 0.88 (N—H), 0.95 (aromatic), 0.99 (CH2) or 0.98 Å (CH3), and Uiso(H) = 1.25Ueq(X). The high Rint value is the result of weak high-angle data.
Data collection: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); cell refinement: DENZO and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON97 (Spek, 1997); software used to prepare material for publication: SHELXL97.
Fig. 1. The molecular structure and atom-numbering scheme for the title compound, showing 50% probability ellipsoids and the resolved twofold disorder. |
C15H23N2O4S | Dx = 1.257 Mg m−3 |
Mr = 327.41 | Melting point: 335-336 K K |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 19.663 (4) Å | Cell parameters from 7703 reflections |
b = 13.177 (3) Å | θ = 2.9–27.5° |
c = 13.708 (3) Å | µ = 0.21 mm−1 |
β = 103.69 (3)° | T = 150 K |
V = 3450.8 (13) Å3 | Needle, colourless |
Z = 8 | 0.34 × 0.10 × 0.08 mm |
F(000) = 1392 |
Bruker–Nonius KappaCCD area-detector diffractometer | 3916 independent reflections |
Radiation source: Bruker–Nonius FR591 rotating anode | 1830 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.113 |
Detector resolution: 9.091 pixels mm-1 | θmax = 27.5°, θmin = 3.1° |
ϕ and ω scans | h = −25→25 |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | k = −17→17 |
Tmin = 0.933, Tmax = 0.984 | l = −16→17 |
12347 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.096 | H-atom parameters constrained |
wR(F2) = 0.300 | w = 1/[σ2(Fo2) + (0.1206P)2 + 1.7968P] where P = (Fo2 + 2Fc2)/3 |
S = 1.16 | (Δ/σ)max < 0.001 |
3916 reflections | Δρmax = 0.44 e Å−3 |
226 parameters | Δρmin = −0.94 e Å−3 |
32 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0067 (16) |
C15H23N2O4S | V = 3450.8 (13) Å3 |
Mr = 327.41 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 19.663 (4) Å | µ = 0.21 mm−1 |
b = 13.177 (3) Å | T = 150 K |
c = 13.708 (3) Å | 0.34 × 0.10 × 0.08 mm |
β = 103.69 (3)° |
Bruker–Nonius KappaCCD area-detector diffractometer | 3916 independent reflections |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | 1830 reflections with I > 2σ(I) |
Tmin = 0.933, Tmax = 0.984 | Rint = 0.113 |
12347 measured reflections |
R[F2 > 2σ(F2)] = 0.096 | 32 restraints |
wR(F2) = 0.300 | H-atom parameters constrained |
S = 1.16 | Δρmax = 0.44 e Å−3 |
3916 reflections | Δρmin = −0.94 e Å−3 |
226 parameters |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
S1 | 0.24097 (9) | 0.28058 (17) | 0.25123 (11) | 0.1142 (8) | |
C2 | 0.2113 (3) | 0.4050 (6) | 0.2379 (3) | 0.106 (2) | |
N3 | 0.2571 (2) | 0.4739 (4) | 0.2616 (3) | 0.0794 (13) | |
C4 | 0.3231 (2) | 0.4311 (3) | 0.2963 (3) | 0.0542 (10) | |
C41 | 0.3839 (2) | 0.5007 (3) | 0.3288 (3) | 0.0613 (11) | |
C42 | 0.3709 (3) | 0.5699 (4) | 0.4120 (4) | 0.0876 (15) | |
H41 | 0.3279 | 0.6088 | 0.3869 | 0.109* | |
H42 | 0.4105 | 0.6166 | 0.4329 | 0.109* | |
H43 | 0.3662 | 0.5286 | 0.4695 | 0.109* | |
C43 | 0.3915 (3) | 0.5650 (4) | 0.2384 (4) | 0.0886 (16) | |
H44 | 0.4036 | 0.5209 | 0.1875 | 0.111* | |
H45 | 0.4285 | 0.6155 | 0.2604 | 0.111* | |
H46 | 0.3471 | 0.5996 | 0.2097 | 0.111* | |
C44 | 0.4510 (2) | 0.4391 (4) | 0.3677 (4) | 0.0772 (14) | |
H47 | 0.4464 | 0.3986 | 0.4258 | 0.097* | |
H48 | 0.4909 | 0.4854 | 0.3876 | 0.097* | |
H49 | 0.4586 | 0.3938 | 0.3145 | 0.097* | |
C5 | 0.3236 (2) | 0.3286 (4) | 0.2952 (3) | 0.0656 (12) | |
H5 | 0.3645 | 0.2882 | 0.3162 | 0.082* | |
N21A | 0.1424 (4) | 0.4661 (8) | 0.2026 (6) | 0.055 (2) | 0.50 |
H21A | 0.1411 | 0.5328 | 0.2054 | 0.069* | 0.50 |
N21B | 0.1382 (3) | 0.3847 (5) | 0.1981 (4) | 0.0399 (14) | 0.50 |
H21B | 0.1190 | 0.3243 | 0.1859 | 0.050* | 0.50 |
C22A | 0.0865 (4) | 0.4115 (9) | 0.1684 (6) | 0.053 (2) | 0.50 |
H22A | 0.0855 | 0.3396 | 0.1637 | 0.067* | 0.50 |
C22B | 0.1035 (5) | 0.4758 (7) | 0.1825 (6) | 0.038 (2) | 0.50 |
H22B | 0.1279 | 0.5380 | 0.1991 | 0.047* | 0.50 |
C23 | 0.0287 (3) | 0.4745 (5) | 0.1399 (3) | 0.0792 (16) | |
C24 | −0.0184 (4) | 0.3869 (5) | 0.1094 (4) | 0.094 (2) | |
O24 | 0.0001 (3) | 0.2990 (3) | 0.1145 (3) | 0.136 (2) | |
O25 | −0.08609 (18) | 0.4120 (2) | 0.0742 (2) | 0.0738 (10) | |
C26 | −0.1363 (4) | 0.3312 (4) | 0.0391 (4) | 0.0941 (19) | |
H261 | −0.1395 | 0.2856 | 0.0951 | 0.118* | |
H262 | −0.1222 | 0.2908 | −0.0138 | 0.118* | |
C27 | −0.2053 (4) | 0.3834 (4) | −0.0023 (4) | 0.0972 (19) | |
H271 | −0.2180 | 0.4237 | 0.0508 | 0.121* | |
H272 | −0.2415 | 0.3324 | −0.0270 | 0.121* | |
H273 | −0.2011 | 0.4282 | −0.0577 | 0.111 (18)* | |
C28 | 0.0096 (2) | 0.5791 (4) | 0.1345 (3) | 0.0664 (13) | |
O28 | 0.05313 (16) | 0.6464 (3) | 0.1580 (2) | 0.0939 (13) | |
O29 | −0.05840 (13) | 0.5982 (2) | 0.1018 (2) | 0.0588 (8) | |
C30 | −0.0786 (2) | 0.7033 (3) | 0.0974 (3) | 0.0608 (11) | |
H301 | −0.0563 | 0.7410 | 0.0508 | 0.076* | |
H302 | −0.0643 | 0.7348 | 0.1647 | 0.076* | |
C31 | −0.1565 (2) | 0.7051 (4) | 0.0607 (3) | 0.0674 (13) | |
H311 | −0.1697 | 0.6762 | −0.0070 | 0.084* | |
H312 | −0.1732 | 0.7753 | 0.0592 | 0.084* | |
H313 | −0.1776 | 0.6649 | 0.1060 | 0.084* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0885 (12) | 0.1802 (18) | 0.0810 (10) | −0.0665 (11) | 0.0342 (8) | −0.0454 (10) |
N3 | 0.046 (2) | 0.138 (4) | 0.056 (2) | 0.032 (2) | 0.0141 (18) | 0.027 (2) |
C4 | 0.043 (2) | 0.072 (3) | 0.047 (2) | 0.015 (2) | 0.0091 (17) | 0.0065 (19) |
C41 | 0.051 (2) | 0.062 (3) | 0.069 (3) | 0.010 (2) | 0.011 (2) | −0.003 (2) |
C42 | 0.089 (4) | 0.081 (3) | 0.091 (3) | 0.006 (3) | 0.018 (3) | −0.014 (3) |
C43 | 0.085 (4) | 0.082 (4) | 0.105 (4) | 0.005 (3) | 0.036 (3) | 0.014 (3) |
C44 | 0.039 (2) | 0.099 (4) | 0.088 (3) | −0.003 (2) | 0.003 (2) | −0.007 (3) |
C5 | 0.057 (3) | 0.085 (4) | 0.055 (2) | −0.005 (2) | 0.013 (2) | −0.007 (2) |
C24 | 0.126 (5) | 0.112 (5) | 0.061 (3) | 0.078 (4) | 0.055 (3) | 0.045 (3) |
O24 | 0.198 (5) | 0.111 (3) | 0.121 (3) | 0.090 (4) | 0.084 (3) | 0.048 (3) |
O25 | 0.091 (3) | 0.065 (2) | 0.0689 (19) | 0.0110 (19) | 0.0272 (18) | 0.0047 (15) |
C26 | 0.151 (6) | 0.063 (3) | 0.082 (3) | −0.015 (4) | 0.055 (4) | 0.001 (3) |
C27 | 0.130 (5) | 0.091 (4) | 0.069 (3) | −0.053 (4) | 0.022 (3) | 0.002 (3) |
C28 | 0.042 (3) | 0.116 (4) | 0.041 (2) | 0.019 (3) | 0.0111 (18) | 0.015 (2) |
O28 | 0.0385 (17) | 0.169 (4) | 0.070 (2) | −0.023 (2) | 0.0053 (15) | −0.004 (2) |
O29 | 0.0391 (15) | 0.073 (2) | 0.0623 (16) | 0.0056 (14) | 0.0083 (12) | 0.0036 (14) |
C30 | 0.047 (2) | 0.071 (3) | 0.062 (2) | −0.006 (2) | 0.0081 (19) | 0.001 (2) |
C31 | 0.053 (3) | 0.081 (3) | 0.068 (3) | 0.009 (2) | 0.013 (2) | 0.001 (2) |
C2 | 0.047 (3) | 0.228 (6) | 0.044 (2) | 0.000 (4) | 0.014 (2) | −0.003 (4) |
N21A | 0.043 (5) | 0.072 (7) | 0.048 (4) | 0.007 (5) | 0.004 (4) | 0.001 (4) |
N21B | 0.038 (4) | 0.029 (4) | 0.050 (3) | −0.003 (3) | 0.006 (3) | −0.002 (3) |
C22A | 0.053 (6) | 0.057 (6) | 0.050 (5) | 0.013 (6) | 0.012 (4) | 0.005 (5) |
C22B | 0.044 (6) | 0.032 (5) | 0.038 (4) | 0.001 (5) | 0.012 (5) | 0.004 (4) |
C23 | 0.060 (3) | 0.132 (5) | 0.051 (2) | 0.033 (3) | 0.023 (2) | 0.024 (3) |
S1—C5 | 1.715 (5) | N21B—C22B | 1.371 (9) |
S1—C2 | 1.736 (8) | N21B—H21B | 0.88 |
C2—N21A | 1.552 (9) | C22B—H22B | 0.95 |
N3—C2 | 1.266 (7) | C24—O24 | 1.212 (6) |
N3—C4 | 1.392 (5) | C24—O25 | 1.345 (6) |
C4—C5 | 1.352 (6) | C24—C23 | 1.478 (8) |
C4—C41 | 1.487 (6) | O25—C26 | 1.453 (6) |
C41—C42 | 1.528 (6) | C26—C27 | 1.507 (8) |
C41—C44 | 1.534 (6) | C26—H261 | 0.99 |
C41—C43 | 1.537 (6) | C26—H262 | 0.99 |
C42—H41 | 0.98 | C27—H271 | 0.98 |
C42—H42 | 0.98 | C27—H272 | 0.98 |
C42—H43 | 0.98 | C27—H273 | 0.98 |
C43—H44 | 0.98 | C28—O28 | 1.222 (6) |
C43—H45 | 0.98 | C28—O29 | 1.329 (5) |
C43—H46 | 0.98 | C28—C23 | 1.426 (7) |
C44—H47 | 0.98 | O29—C30 | 1.439 (5) |
C44—H48 | 0.98 | C30—C31 | 1.494 (5) |
C44—H49 | 0.98 | C30—H301 | 0.99 |
C5—H5 | 0.95 | C30—H302 | 0.99 |
N21A—C22A | 1.305 (11) | C31—H311 | 0.98 |
N21A—H21A | 0.88 | C31—H312 | 0.98 |
C22A—C23 | 1.386 (10) | C31—H313 | 0.98 |
C22A—H22A | 0.95 | ||
C5—S1—C2 | 87.4 (3) | O25—C26—H262 | 110.6 |
C2—N3—C4 | 110.3 (5) | C27—C26—H262 | 110.6 |
C5—C4—N3 | 114.2 (4) | H261—C26—H262 | 108.7 |
C5—C4—C41 | 127.7 (4) | C26—C27—H271 | 109.5 |
N3—C4—C41 | 118.1 (4) | C26—C27—H272 | 109.5 |
C4—C41—C42 | 109.1 (4) | H271—C27—H272 | 109.5 |
C4—C41—C44 | 110.0 (4) | C26—C27—H273 | 109.5 |
C42—C41—C44 | 109.7 (4) | H271—C27—H273 | 109.5 |
C4—C41—C43 | 108.8 (4) | H272—C27—H273 | 109.5 |
C42—C41—C43 | 109.7 (4) | O28—C28—O29 | 122.5 (5) |
C44—C41—C43 | 109.4 (4) | O28—C28—C23 | 121.9 (4) |
C41—C42—H41 | 109.5 | O29—C28—C23 | 115.6 (5) |
C41—C42—H42 | 109.5 | C28—O29—C30 | 116.2 (4) |
H41—C42—H42 | 109.5 | O29—C30—C31 | 106.3 (3) |
C41—C42—H43 | 109.5 | O29—C30—H301 | 110.5 |
H41—C42—H43 | 109.5 | C31—C30—H301 | 110.5 |
H42—C42—H43 | 109.5 | O29—C30—H302 | 110.5 |
C41—C43—H44 | 109.5 | C31—C30—H302 | 110.5 |
C41—C43—H45 | 109.5 | H301—C30—H302 | 108.7 |
H44—C43—H45 | 109.5 | C30—C31—H311 | 109.5 |
C41—C43—H46 | 109.5 | C30—C31—H312 | 109.5 |
H44—C43—H46 | 109.5 | H311—C31—H312 | 109.5 |
H45—C43—H46 | 109.5 | C30—C31—H313 | 109.5 |
C41—C44—H47 | 109.5 | H311—C31—H313 | 109.5 |
C41—C44—H48 | 109.5 | H312—C31—H313 | 109.5 |
H47—C44—H48 | 109.5 | N3—C2—N21A | 102.9 (7) |
C41—C44—H49 | 109.5 | N3—C2—S1 | 116.8 (4) |
H47—C44—H49 | 109.5 | N21A—C2—S1 | 140.3 (6) |
H48—C44—H49 | 109.5 | C22A—N21A—C2 | 115.2 (9) |
C4—C5—S1 | 111.3 (4) | C22A—N21A—H21A | 122.4 |
C4—C5—H5 | 124.3 | C2—N21A—H21A | 122.4 |
S1—C5—H5 | 124.3 | N21A—C22A—C23 | 109.6 (10) |
O24—C24—O25 | 121.0 (8) | N21A—C22A—H22A | 125.2 |
O24—C24—C23 | 124.8 (6) | C23—C22A—H22A | 125.2 |
O25—C24—C23 | 114.3 (4) | C22A—C23—C28 | 141.5 (7) |
C24—O25—C26 | 118.4 (5) | C22A—C23—C24 | 91.7 (6) |
O25—C26—C27 | 105.7 (4) | C28—C23—C24 | 126.9 (4) |
O25—C26—H261 | 110.6 | C22B—N21B—H21B | 125.9 |
C27—C26—H261 | 110.6 | N21B—C22B—H22B | 120.9 |
C2—N3—C4—C5 | 1.2 (5) | C4—N3—C2—N21A | 179.5 (4) |
C2—N3—C4—C41 | −179.4 (4) | C4—N3—C2—S1 | −1.4 (5) |
C5—C4—C41—C42 | −123.1 (4) | C5—S1—C2—N3 | 1.0 (4) |
N3—C4—C41—C42 | 57.6 (5) | C5—S1—C2—N21A | 179.7 (6) |
C5—C4—C41—C44 | −2.7 (5) | N3—C2—N21A—C22A | 176.4 (6) |
N3—C4—C41—C44 | 178.0 (3) | S1—C2—N21A—C22A | −2.4 (10) |
C5—C4—C41—C43 | 117.2 (4) | C2—N21A—C22A—C23 | 179.7 (5) |
N3—C4—C41—C43 | −62.1 (4) | N21A—C22A—C23—C28 | 0.6 (11) |
N3—C4—C5—S1 | −0.4 (4) | N21A—C22A—C23—C24 | −179.6 (6) |
C41—C4—C5—S1 | −179.8 (3) | O28—C28—C23—C22A | 2.8 (9) |
C2—S1—C5—C4 | −0.3 (3) | O29—C28—C23—C22A | −177.7 (6) |
O24—C24—O25—C26 | −2.1 (6) | O28—C28—C23—C24 | −177.0 (4) |
C23—C24—O25—C26 | 177.9 (4) | O29—C28—C23—C24 | 2.5 (6) |
C24—O25—C26—C27 | −175.8 (3) | O24—C24—C23—C22A | −0.4 (6) |
O28—C28—O29—C30 | −1.3 (5) | O25—C24—C23—C22A | 179.6 (4) |
C23—C28—O29—C30 | 179.1 (3) | O24—C24—C23—C28 | 179.4 (4) |
C28—O29—C30—C31 | −179.0 (3) | O25—C24—C23—C28 | −0.6 (6) |
D—H···A | D—H | H···A | D···A | D—H···A |
N21A—H21A···O28 | 0.88 | 2.26 | 2.931 (10) | 133 |
N21B—H21B···O24 | 0.88 | 2.33 | 2.913 (9) | 123 |
C5—H5···O28i | 0.95 | 2.44 | 3.363 (7) | 163 |
Symmetry code: (i) −x+1/2, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H23N2O4S |
Mr | 327.41 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 150 |
a, b, c (Å) | 19.663 (4), 13.177 (3), 13.708 (3) |
β (°) | 103.69 (3) |
V (Å3) | 3450.8 (13) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.21 |
Crystal size (mm) | 0.34 × 0.10 × 0.08 |
Data collection | |
Diffractometer | Bruker–Nonius KappaCCD area-detector diffractometer |
Absorption correction | Multi-scan (SORTAV; Blessing, 1995) |
Tmin, Tmax | 0.933, 0.984 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 12347, 3916, 1830 |
Rint | 0.113 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.096, 0.300, 1.16 |
No. of reflections | 3916 |
No. of parameters | 226 |
No. of restraints | 32 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.44, −0.94 |
Computer programs: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998), DENZO and COLLECT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON97 (Spek, 1997), SHELXL97.
D—H···A | D—H | H···A | D···A | D—H···A |
N21A—H21A···O28 | 0.88 | 2.26 | 2.931 (10) | 132.5 |
N21B—H21B···O24 | 0.88 | 2.33 | 2.913 (9) | 123.4 |
C5—H5···O28i | 0.95 | 2.44 | 3.363 (7) | 163.0 |
Symmetry code: (i) −x+1/2, y−1/2, −z+1/2. |
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2-Aminothiazole derivatives have a variety of pharmaceutical properties and recent experience has shown us that they are generally easy compounds to crystallize, or cocrystallize. There are currently 157 crystal structures (Cambridge Structural Database, September 2002 release; Allen, 2002) containing a 2-aminothiazole moiety. Only two of these structures have a 4-tert-butyl group, namely 4-tert-butyl-2-(N-methyl-N-phenylamino)thiazole-5-carbaldehyde (Gillon et al., 1983) and anti-5-acetyl-2-dimethylamino-4-tert-butylthiazole (Caldwell et al., 1987). The crystallographic quality of these two structures is very good, considering the potential for disorder in tert-butyl groups. Ironically, in the title compound, (I), the groups where disorder might be more likely, such as the tert-butyl and/or the ethyl esters, are relatively rigid, compared to the rest of the molecule. Large and very anisotropic displacement ellipsoids for three of the thiazole ring atoms (S1, C2 and N3) and the malonate atoms means that several atoms could be split into two positions each, but attempts to do so resulted in totally unrealistic bond distances and angles. The crystallographic results for (I) are of low precision, and a poor data set was the direct result of poor crystal quality. However, the resolvable disorder in this molecule and the probable unresolved disorder in the atoms with high displacement parameters is worth reporting. The structure of (I) comprises an essentially planar molecule, except for the tert-butyl group, with resolved disorder of the aminomethylene atoms (Fig. 1). All the molecules in the unit cell lie essentially parallel to the ab plane. The aminomethylene atoms (N21 and C22) are both equally disordered over two sites; thus, two alternative intramolecular hydrogen bonds exists from the partial amine H atoms to the adjacent carbonyl O atoms (Table 1). An additional C—H···O close contact is observed from the only thiazole ring H atom to one of the carbonyl O atoms in an adjacent molecule.