Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807034150/lh2458sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807034150/lh2458Isup2.hkl |
CCDC reference: 657787
Key indicators
- Single-crystal X-ray study
- T = 173 K
- Mean (C-C) = 0.005 Å
- R factor = 0.042
- wR factor = 0.103
- Data-to-parameter ratio = 13.2
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT222_ALERT_3_C Large Non-Solvent H Ueq(max)/Ueq(min) ... 3.77 Ratio PLAT431_ALERT_2_C Short Inter HL..A Contact Br1 .. O4 .. 3.18 Ang.
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
For related structures, see: Shan et al. (2004); Ali et al. (2004); Yathirajan et al. (2006). For related literature, see: Varma et al. (1986); Misra et al. (1981); Agarwal et al. (1983); Singh & Dash (1988); Hodnett & Dunn (1970).
A mixture of 2-bromo-5-methoxybenzohydrazide (0.735 g, 0.003 mol) and 4-nitrobenzaldehyde (0.453 g, 0.003 mol) in 15 ml of absolute alcohol containing 2 drops of dilute sulfuric acid was refluxed for about 3 h. On cooling, the solid separated was filtered and recrystallized from ethyl acetate (m.p.: 462–464 K). Analysis for C15H12BrN3O4: Found (Calculated): C: 47.55 (47.64); H: 3.16 (3.20); N:11.06% (11.11%).
H atoms were found in a difference map, but those bonded to C were refined using a riding model with C—H = 0.95 Å and Uiso(H) = 1.2Ueq(C) [C—H = 0.98 Å and Uiso(H) = 1.5Ueq(C) for the methyl group, which was allowed to rotate but not to tip]. The H atom bonded to N was freely refined.
Schiff bases are used as substrates in the preparation of number of industrial and biologically active compounds via ring closure, cycloaddition and replacement reactions. Some Schiff base derivatives were reported to possess antimicrobial, anti-inflammatory and central nervous system activities and moreover, Schiff bases are also known to have biological activities such as antimicrobial, antifungal, antitumor, and as herbicides (Varma et al., 1986; Misra et al., 1981; Agarwal et al., 1983; Singh et al., 1988; Hodnett et al., 1970). The title compound has been synthesized and its crystal structure is reported herein.
The geometric parameters of the title molecule, C15H12BrN3O4, are in the usual ranges. The dihedral angle between the two benzene rings is 49.69 (10)°. In the crystal structure, molecules are connected by intermolecular N—H···O hydrogen bonds to form one-dimensional chain in the c axis direction.
Similar structures related to the title compound that have already been reported are 2-chloro-3,4-dimethoxybenzaldehyde (4-nitrophenyl)hydrazone (Shan et al., 2004), 1-(4-fluoro-2-hydroxyphenyl)ethanone 4-nitrobenzoylhydrazone (Ali et al., 2004) and 3-(2-bromo-5-methoxyphenyl)-5-methyl-1-(4-phenyl-1,3-thiazol-2-yl)- 1H-1,2,4-triazole (Yathirajan et al., 2006).
For related structures, see: Shan et al. (2004); Ali et al. (2004); Yathirajan et al. (2006). For related literature, see: Varma et al. (1986); Misra et al. (1981); Agarwal et al. (1983); Singh & Dash (1988); Hodnett & Dunn (1970).
Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.
Fig. 1. The molecular structure with the atom numbering; displacement ellipsoids are at the 50% probability level. | |
Fig. 2. The reaction scheme |
C15H12BrN3O4 | F(000) = 760 |
Mr = 378.19 | Dx = 1.665 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 9399 reflections |
a = 7.2604 (8) Å | θ = 3.6–25.7° |
b = 21.8931 (19) Å | µ = 2.75 mm−1 |
c = 9.5795 (12) Å | T = 173 K |
β = 97.882 (9)° | Block, light yellow |
V = 1508.3 (3) Å3 | 0.33 × 0.32 × 0.30 mm |
Z = 4 |
Stoe IPDS II two-circle diffractometer | 2818 independent reflections |
Radiation source: fine-focus sealed tube | 2368 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.060 |
ω scans | θmax = 25.7°, θmin = 3.5° |
Absorption correction: multi-scan (MULABS; Spek, 2003; Blessing, 1995) | h = −8→8 |
Tmin = 0.414, Tmax = 0.436 | k = −24→26 |
9259 measured reflections | l = −11→9 |
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)] = 0.042 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.103 | w = 1/[σ2(Fo2) + (0.0687P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max = 0.001 |
2818 reflections | Δρmax = 0.79 e Å−3 |
214 parameters | Δρmin = −1.01 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0053 (10) |
C15H12BrN3O4 | V = 1508.3 (3) Å3 |
Mr = 378.19 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.2604 (8) Å | µ = 2.75 mm−1 |
b = 21.8931 (19) Å | T = 173 K |
c = 9.5795 (12) Å | 0.33 × 0.32 × 0.30 mm |
β = 97.882 (9)° |
Stoe IPDS II two-circle diffractometer | 2818 independent reflections |
Absorption correction: multi-scan (MULABS; Spek, 2003; Blessing, 1995) | 2368 reflections with I > 2σ(I) |
Tmin = 0.414, Tmax = 0.436 | Rint = 0.060 |
9259 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.103 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.79 e Å−3 |
2818 reflections | Δρmin = −1.01 e Å−3 |
214 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 | ||
Br1 | 0.32579 (4) | 0.100500 (15) | 0.57802 (4) | 0.02733 (15) | |
O1 | 0.5025 (3) | 0.22410 (11) | 0.7115 (2) | 0.0269 (5) | |
O2 | 1.0036 (3) | 0.15890 (12) | 0.3018 (3) | 0.0331 (6) | |
O3 | 0.1301 (4) | 0.64942 (13) | 0.5891 (4) | 0.0529 (8) | |
O4 | 0.0367 (4) | 0.60609 (13) | 0.7701 (3) | 0.0408 (7) | |
N1 | 0.4881 (3) | 0.28121 (12) | 0.5111 (3) | 0.0196 (5) | |
H1 | 0.502 (4) | 0.2827 (16) | 0.425 (4) | 0.017 (8)* | |
N2 | 0.4182 (3) | 0.33185 (12) | 0.5697 (3) | 0.0204 (5) | |
N3 | 0.1128 (4) | 0.60476 (13) | 0.6635 (3) | 0.0293 (7) | |
C1 | 0.5290 (4) | 0.22977 (14) | 0.5886 (3) | 0.0184 (6) | |
C2 | 0.3788 (4) | 0.37684 (15) | 0.4844 (3) | 0.0219 (6) | |
H2 | 0.3959 | 0.3726 | 0.3883 | 0.026* | |
C11 | 0.6152 (4) | 0.18073 (14) | 0.5101 (3) | 0.0186 (6) | |
C12 | 0.5502 (4) | 0.12071 (15) | 0.5056 (3) | 0.0208 (6) | |
C13 | 0.6396 (4) | 0.07531 (16) | 0.4399 (4) | 0.0251 (7) | |
H13 | 0.5944 | 0.0346 | 0.4383 | 0.030* | |
C14 | 0.7945 (5) | 0.08914 (16) | 0.3766 (4) | 0.0261 (7) | |
H14 | 0.8587 | 0.0576 | 0.3350 | 0.031* | |
C15 | 0.8564 (4) | 0.14933 (16) | 0.3737 (3) | 0.0232 (7) | |
C16 | 0.7690 (4) | 0.19505 (15) | 0.4417 (3) | 0.0205 (6) | |
H16 | 0.8133 | 0.2359 | 0.4418 | 0.025* | |
C17 | 1.0707 (5) | 0.22025 (19) | 0.2950 (5) | 0.0428 (10) | |
H17A | 0.9718 | 0.2463 | 0.2471 | 0.064* | |
H17B | 1.1775 | 0.2208 | 0.2426 | 0.064* | |
H17C | 1.1089 | 0.2356 | 0.3907 | 0.064* | |
C21 | 0.3078 (4) | 0.43461 (14) | 0.5336 (3) | 0.0197 (6) | |
C22 | 0.2838 (4) | 0.48389 (15) | 0.4405 (3) | 0.0216 (6) | |
H22 | 0.3100 | 0.4789 | 0.3467 | 0.026* | |
C23 | 0.2223 (4) | 0.54005 (15) | 0.4830 (4) | 0.0230 (7) | |
H23 | 0.2067 | 0.5736 | 0.4197 | 0.028* | |
C24 | 0.1842 (4) | 0.54577 (14) | 0.6200 (4) | 0.0221 (7) | |
C25 | 0.2056 (4) | 0.49770 (15) | 0.7154 (3) | 0.0234 (7) | |
H25 | 0.1775 | 0.5028 | 0.8087 | 0.028* | |
C26 | 0.2688 (4) | 0.44214 (15) | 0.6716 (3) | 0.0221 (7) | |
H26 | 0.2858 | 0.4089 | 0.7358 | 0.026* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0317 (2) | 0.0242 (2) | 0.0281 (2) | −0.00598 (13) | 0.01127 (13) | 0.00084 (14) |
O1 | 0.0430 (12) | 0.0234 (12) | 0.0163 (12) | 0.0023 (10) | 0.0114 (9) | 0.0011 (9) |
O2 | 0.0347 (12) | 0.0298 (14) | 0.0395 (14) | 0.0040 (10) | 0.0224 (10) | −0.0036 (11) |
O3 | 0.077 (2) | 0.0188 (14) | 0.068 (2) | 0.0059 (13) | 0.0277 (17) | −0.0039 (15) |
O4 | 0.0419 (14) | 0.0404 (17) | 0.0426 (16) | 0.0102 (11) | 0.0143 (12) | −0.0153 (13) |
N1 | 0.0288 (12) | 0.0176 (13) | 0.0143 (13) | 0.0045 (10) | 0.0094 (10) | 0.0007 (11) |
N2 | 0.0234 (12) | 0.0165 (13) | 0.0224 (14) | 0.0013 (10) | 0.0075 (10) | −0.0029 (11) |
N3 | 0.0263 (13) | 0.0224 (16) | 0.0389 (18) | 0.0001 (11) | 0.0031 (12) | −0.0104 (14) |
C1 | 0.0185 (12) | 0.0187 (16) | 0.0184 (16) | −0.0015 (11) | 0.0041 (11) | 0.0015 (13) |
C2 | 0.0221 (13) | 0.0228 (17) | 0.0215 (16) | 0.0008 (12) | 0.0058 (12) | 0.0021 (13) |
C11 | 0.0231 (13) | 0.0178 (16) | 0.0150 (14) | 0.0038 (11) | 0.0033 (11) | 0.0017 (12) |
C12 | 0.0243 (14) | 0.0195 (16) | 0.0187 (15) | 0.0003 (12) | 0.0032 (12) | 0.0017 (13) |
C13 | 0.0329 (15) | 0.0158 (16) | 0.0265 (18) | 0.0025 (13) | 0.0039 (13) | 0.0013 (14) |
C14 | 0.0320 (16) | 0.0218 (17) | 0.0253 (17) | 0.0088 (12) | 0.0065 (13) | −0.0055 (14) |
C15 | 0.0233 (14) | 0.0283 (18) | 0.0186 (15) | 0.0050 (12) | 0.0048 (11) | 0.0002 (13) |
C16 | 0.0217 (13) | 0.0180 (15) | 0.0221 (16) | 0.0016 (11) | 0.0036 (11) | −0.0004 (13) |
C17 | 0.0408 (19) | 0.037 (2) | 0.058 (3) | −0.0026 (16) | 0.0311 (18) | −0.001 (2) |
C21 | 0.0154 (12) | 0.0183 (15) | 0.0252 (16) | −0.0023 (11) | 0.0020 (11) | −0.0018 (13) |
C22 | 0.0254 (14) | 0.0222 (17) | 0.0184 (15) | 0.0016 (12) | 0.0069 (11) | −0.0004 (13) |
C23 | 0.0226 (13) | 0.0180 (16) | 0.0280 (17) | −0.0002 (11) | 0.0026 (12) | 0.0016 (14) |
C24 | 0.0171 (12) | 0.0193 (16) | 0.0298 (17) | −0.0011 (11) | 0.0026 (12) | −0.0079 (14) |
C25 | 0.0210 (13) | 0.0267 (17) | 0.0237 (17) | −0.0014 (12) | 0.0073 (12) | −0.0025 (14) |
C26 | 0.0198 (13) | 0.0241 (17) | 0.0225 (16) | −0.0015 (11) | 0.0037 (11) | 0.0013 (13) |
Br1—C12 | 1.908 (3) | C13—H13 | 0.9500 |
O1—C1 | 1.225 (4) | C14—C15 | 1.394 (5) |
O2—C15 | 1.364 (4) | C14—H14 | 0.9500 |
O2—C17 | 1.434 (5) | C15—C16 | 1.394 (4) |
O3—N3 | 1.226 (4) | C16—H16 | 0.9500 |
O4—N3 | 1.227 (4) | C17—H17A | 0.9800 |
N1—C1 | 1.359 (4) | C17—H17B | 0.9800 |
N1—N2 | 1.371 (4) | C17—H17C | 0.9800 |
N1—H1 | 0.85 (4) | C21—C22 | 1.395 (4) |
N2—C2 | 1.287 (4) | C21—C26 | 1.400 (5) |
N3—C24 | 1.473 (4) | C22—C23 | 1.388 (5) |
C1—C11 | 1.497 (4) | C22—H22 | 0.9500 |
C2—C21 | 1.468 (5) | C23—C24 | 1.384 (5) |
C2—H2 | 0.9500 | C23—H23 | 0.9500 |
C11—C12 | 1.395 (4) | C24—C25 | 1.389 (5) |
C11—C16 | 1.405 (4) | C25—C26 | 1.385 (5) |
C12—C13 | 1.385 (5) | C25—H25 | 0.9500 |
C13—C14 | 1.382 (5) | C26—H26 | 0.9500 |
C15—O2—C17 | 117.5 (3) | C14—C15—C16 | 120.0 (3) |
C1—N1—N2 | 120.8 (3) | C15—C16—C11 | 120.0 (3) |
C1—N1—H1 | 121 (2) | C15—C16—H16 | 120.0 |
N2—N1—H1 | 118 (2) | C11—C16—H16 | 120.0 |
C2—N2—N1 | 114.9 (3) | O2—C17—H17A | 109.5 |
O3—N3—O4 | 124.0 (3) | O2—C17—H17B | 109.5 |
O3—N3—C24 | 117.8 (3) | H17A—C17—H17B | 109.5 |
O4—N3—C24 | 118.2 (3) | O2—C17—H17C | 109.5 |
O1—C1—N1 | 123.9 (3) | H17A—C17—H17C | 109.5 |
O1—C1—C11 | 122.8 (3) | H17B—C17—H17C | 109.5 |
N1—C1—C11 | 113.3 (3) | C22—C21—C26 | 119.3 (3) |
N2—C2—C21 | 120.9 (3) | C22—C21—C2 | 118.7 (3) |
N2—C2—H2 | 119.6 | C26—C21—C2 | 122.0 (3) |
C21—C2—H2 | 119.6 | C23—C22—C21 | 121.0 (3) |
C12—C11—C16 | 118.9 (3) | C23—C22—H22 | 119.5 |
C12—C11—C1 | 121.9 (3) | C21—C22—H22 | 119.5 |
C16—C11—C1 | 119.2 (3) | C24—C23—C22 | 118.2 (3) |
C13—C12—C11 | 120.8 (3) | C24—C23—H23 | 120.9 |
C13—C12—Br1 | 118.4 (2) | C22—C23—H23 | 120.9 |
C11—C12—Br1 | 120.6 (2) | C23—C24—C25 | 122.5 (3) |
C14—C13—C12 | 120.2 (3) | C23—C24—N3 | 118.1 (3) |
C14—C13—H13 | 119.9 | C25—C24—N3 | 119.4 (3) |
C12—C13—H13 | 119.9 | C26—C25—C24 | 118.5 (3) |
C13—C14—C15 | 120.0 (3) | C26—C25—H25 | 120.7 |
C13—C14—H14 | 120.0 | C24—C25—H25 | 120.7 |
C15—C14—H14 | 120.0 | C25—C26—C21 | 120.5 (3) |
O2—C15—C14 | 115.6 (3) | C25—C26—H26 | 119.7 |
O2—C15—C16 | 124.3 (3) | C21—C26—H26 | 119.7 |
C1—N1—N2—C2 | −177.6 (3) | C14—C15—C16—C11 | −1.6 (4) |
N2—N1—C1—O1 | 2.2 (4) | C12—C11—C16—C15 | −1.5 (4) |
N2—N1—C1—C11 | −176.2 (2) | C1—C11—C16—C15 | 177.0 (3) |
N1—N2—C2—C21 | −178.3 (2) | N2—C2—C21—C22 | 174.0 (3) |
O1—C1—C11—C12 | 51.0 (4) | N2—C2—C21—C26 | −4.1 (4) |
N1—C1—C11—C12 | −130.5 (3) | C26—C21—C22—C23 | 0.1 (4) |
O1—C1—C11—C16 | −127.4 (3) | C2—C21—C22—C23 | −178.1 (3) |
N1—C1—C11—C16 | 51.0 (3) | C21—C22—C23—C24 | −0.4 (4) |
C16—C11—C12—C13 | 2.6 (4) | C22—C23—C24—C25 | 0.1 (4) |
C1—C11—C12—C13 | −175.8 (3) | C22—C23—C24—N3 | −177.9 (3) |
C16—C11—C12—Br1 | −172.9 (2) | O3—N3—C24—C23 | −16.3 (4) |
C1—C11—C12—Br1 | 8.6 (4) | O4—N3—C24—C23 | 162.5 (3) |
C11—C12—C13—C14 | −0.6 (5) | O3—N3—C24—C25 | 165.6 (3) |
Br1—C12—C13—C14 | 175.1 (2) | O4—N3—C24—C25 | −15.7 (4) |
C12—C13—C14—C15 | −2.6 (5) | C23—C24—C25—C26 | 0.5 (4) |
C17—O2—C15—C14 | 179.4 (3) | N3—C24—C25—C26 | 178.5 (2) |
C17—O2—C15—C16 | −0.6 (5) | C24—C25—C26—C21 | −0.8 (4) |
C13—C14—C15—O2 | −176.3 (3) | C22—C21—C26—C25 | 0.5 (4) |
C13—C14—C15—C16 | 3.7 (5) | C2—C21—C26—C25 | 178.7 (3) |
O2—C15—C16—C11 | 178.4 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.85 (4) | 2.05 (4) | 2.889 (4) | 171 (3) |
Symmetry code: (i) x, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H12BrN3O4 |
Mr | 378.19 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 173 |
a, b, c (Å) | 7.2604 (8), 21.8931 (19), 9.5795 (12) |
β (°) | 97.882 (9) |
V (Å3) | 1508.3 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 2.75 |
Crystal size (mm) | 0.33 × 0.32 × 0.30 |
Data collection | |
Diffractometer | Stoe IPDS II two-circle |
Absorption correction | Multi-scan (MULABS; Spek, 2003; Blessing, 1995) |
Tmin, Tmax | 0.414, 0.436 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9259, 2818, 2368 |
Rint | 0.060 |
(sin θ/λ)max (Å−1) | 0.610 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.103, 1.02 |
No. of reflections | 2818 |
No. of parameters | 214 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.79, −1.01 |
Computer programs: X-AREA (Stoe & Cie, 2001), X-AREA, SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.85 (4) | 2.05 (4) | 2.889 (4) | 171 (3) |
Symmetry code: (i) x, −y+1/2, z−1/2. |
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Schiff bases are used as substrates in the preparation of number of industrial and biologically active compounds via ring closure, cycloaddition and replacement reactions. Some Schiff base derivatives were reported to possess antimicrobial, anti-inflammatory and central nervous system activities and moreover, Schiff bases are also known to have biological activities such as antimicrobial, antifungal, antitumor, and as herbicides (Varma et al., 1986; Misra et al., 1981; Agarwal et al., 1983; Singh et al., 1988; Hodnett et al., 1970). The title compound has been synthesized and its crystal structure is reported herein.
The geometric parameters of the title molecule, C15H12BrN3O4, are in the usual ranges. The dihedral angle between the two benzene rings is 49.69 (10)°. In the crystal structure, molecules are connected by intermolecular N—H···O hydrogen bonds to form one-dimensional chain in the c axis direction.
Similar structures related to the title compound that have already been reported are 2-chloro-3,4-dimethoxybenzaldehyde (4-nitrophenyl)hydrazone (Shan et al., 2004), 1-(4-fluoro-2-hydroxyphenyl)ethanone 4-nitrobenzoylhydrazone (Ali et al., 2004) and 3-(2-bromo-5-methoxyphenyl)-5-methyl-1-(4-phenyl-1,3-thiazol-2-yl)- 1H-1,2,4-triazole (Yathirajan et al., 2006).