Avance Bruker 600 MHz was used for nuclear magnetic resonance experiments. Carlo Erba Strumentazion-Mod-1106, Italy was used for Elemental analysis. Precoated silica gel aluminum plates (Kieselgel 60, 254, E. Merck, Germany) were utilized for thin layer chromatography. Chromatograms were visualized by UV at 254 and 365 nm. Finnigan MAT-311A, Germany, was utilized for electron impact mass spectra (EI-MS).
4.2. General Procedure for the Synthesis of (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(arylidene) Acetohydrazide Synthesis of the series of acetohyrazide was done on basis of previously described reaction procedure in published paper by our group [13]. All the derivatives were subjected to 1H NMR for structural elucidation and confirmation.
4.2.1. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(4-methylbenzylidene) Acetohydrazide (1) Yield: 170.6%. m. p. 86°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.10 (s, 1H), 8.37 (s, 1H), 7.94–7.88 (m, 2H), 7.43–7.37 (m, 2H), 3.83 (s, 2H), 2.83 (s, 3H), 2.56 (s, 3H), 2.32 (s, 3H); HR-ESI-MS: m/z calcd for C15H17N3OS, [M]+ 360.1508; Found 360.1517; 13C NMR (150 MHz, DMSO): δ 159.4, 150.4, 144.1, 140.7, 130.7, 129.1, 129.1, 126.1, 126.1, 122.5, 171.0, 36.4, 21.3, 19.6, 10.6; Anal. Calcd for C15H17N3OS, C, 62.69; H, 5.96; N, 14.62; Found C, 62.60; H, 5.88; N, 14.54.
4.2.2. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2-methylbenzylidene) Acetohydrazide (2) Yield: 83%. m. p. 206.2°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.20 (s, 1H), 8.35 (s, 1H), 7.75–7.68 (m, 2H), 7.23 (d, J = 4.0 Hz, 3H), 3.83 (s, 2H), 2.83 (s, 3H), 2.43 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C15H17N3OS, [M]+ 287.3810; Found 287.3801; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 143.3, 135.3, 131.1, 130.9, 129.0, 126.5, 125.8, 122.5, 36.4, 19.6, 18.9, 10.6; Anal. Calcd for C15H17N3OS, C, 62.69; H, 5.96; N, 14.62; Found C, 62.61; H, 5.87; N, 14.52.
4.2.3. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(3-hydroxy-4-methoxybenzylidene) Acetohydrazide (3) Yield: 82%. m. p. 187.5°C; white powder; 1H NMR (600 MHz, DMSO): δ 11.30 (s, 1H), 9.31 (s, 1H), 8.35 (s, 1H), 7.40 (dd, J = 2.1, 1.1 Hz, 1H), 7.11 (ddd, J = 7.5, 2.1, 1.1 Hz, 1H), 7.07-7.02 (m, 2H), 3.74 (s, 2H), 2.84 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C15H17N3O3S, [M]+ 319.3790; Found 319.3779; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 152.4, 150.4, 147.3, 146.8, 131.1, 122.8, 122.5, 115.9, 112.3, 56.1, 36.4, 19.6, 10.6; Anal. Calcd for C15H17N3O3S, C, 56.41; H, 5.37; N, 13.16; Found C, 56.32; H, 5.31; N, 13.09.
4.2.4. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2-hydroxy-4-methoxybenzylidene) Acetohydrazide (4) Yield: 84%. m. p. 201°C; yellow; 1H NMR (600 MHz, DMSO): δ 10.30 (s, 1H), 9.40 (s, 1H), 8.78 (d, J = 6.0 Hz, 1H), 7.75 (dd, J = 7.5, 2.0 Hz, 1H), 6.53 (dd, J = 7.5, 2.0 Hz, 1H), 6.47 (d, J = 2.1 Hz, 1H), 3.86 (m, 3H), 3.50 (s, 2H), 2.83 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C15H17N3O3S, [M]+ 319.3790; Found 319.3782; 13C NMR (150 MHz, DMSO): δ 171.0, 164.3, 162.1, 159.4, 150.4, 146.0, 133.4, 122.5, 110.8, 107.0, 103.4, 55.8, 36.4, 19.6, 10.6; Anal. Calcd for C15H17N3O3S, C, 56.41; H, 5.37; N, 13.16; Found C, 56.31; H, 5.32; N, 13.11.
4.2.5. (E)-N′-(2,5-Dihydroxybenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (5) Yield: 87%. m. p. 180°C; brown; 1H NMR (600 MHz, DMSO): δ 11.20 (s, 1H), 10.30 (s, 1H), 9.10 (s, 1H), 8.39 (s, 1H), 8.78 (d, J = 6.0 Hz, 1H), 6.78 (d, J = 6.0, 2.0 Hz, 1H), 6.77-6.69 (m, 1H), 3.85 (s, 2H), 2.86 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O3S, [M]+ 305.3520; Found 305.3512; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 153.7, 151.2, 150.4, 146.0, 122.5, 120.4, 119.9,119.6,116.3, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O3S, C, 55.07; H, 4.95; N, 13.76; Found C, 55.01; H, 4.90; N, 13.68;
4.2.6. (E)-N′-(2,3-Dihydroxybenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (6) Yield: 83%. m. p. 163°C; brown; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 10.10 (s, 1H), 9.40 (s, 1H), 8.40 (s, 1H), 8.78 (d, J = 6.0 Hz, 1H), 7.01 (d, J = 7.0 Hz, 1H), 6.83-6.76 (m, 1H), 3.83 (s, 2H), 2.84 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O3S, [M]+ 305.3520; Found 305.3508; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 151.7, 150.4, 146.1, 146.0, 124.7, 122.5, 122.8, 119.9, 119.6, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O3S, C, 55.07; H, 4.95; N, 13.76; Found C, 55.01; H, 4.90; N, 13.71.
4.2.7. (E)-N′-(2,4-Dihydroxybenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (7) Yield: 80%. m. p. 207°C; pale yellow; 1H NMR (600 MHz, DMSO): δ 10.60 (s, 2H), 10.20 (s,1H), 8.80 (s, 1H), 8.60 (d, J = 2.0 Hz, 1H), 7.70 (dd, J = 8.0, 2.0 Hz, 1H), 6.40 (dd, J = 8.0, 2.0 Hz, 1H), 3.40 (s, 2H), 2.80 (s, 3H), 2.35 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O3S, [M]+ 305.3520; Found 305.3505; 13C NMR (150 MHz, DMSO): δ 170.0, 158.4, 153.4, 151.0, 150.2, 146.2, 122.1, 120.2, 119.6, 119.3,116.0, 36.6, 19.8, 10.9; Anal. Calcd for C14H15N3O3S, C, 55.07; H, 4.95; N, 13.76; Found C, 55.00; H, 4.85; N, 13.65.
4.2.8. (E)-N′-(3,4-Dihydroxybenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (8) Yield: 79%. m. p. 216°C; brown cystals; 1H NMR (600 MHz, DMSO): δ 11.10 (s, 1H), 9.62 (s, 1H), 9.17 (s, 1H), 8.37 (s, 1H), 6.93 (d, J = 7.5 Hz, 1H), 6.88 (dd, J = 2.0 Hz, 1H), 6.82 (d, J = 7.4 Hz, 1H), 3.61 (s, 2H), 2.64 (s, 3H), 2.30 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O3S, [M]+ 305.3520; Found 305.3531; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 149.6, 146.8, 146.1, 131.3, 123.2, 122.5, 117.4, 116.3, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O3S, C, 55.07; H, 4.95; N, 13.76; Found C, 55.00; H, 4.87; N, 13.69.
4.2.9. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(3-hydroxybenzylidene) Acetohydrazide (9) Yield: 81%. m. p. 157°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 10.10 (s, 1H), 8.37 (s, 1H), 7.20 (t, J = 7.5 Hz, 1H), 7.09-7.02 (m, 1H), 6.92 (dt, J = 7.5, 1.8 Hz, 1H), 6.87 (d, J = 2.0 Hz, 1H), 3.84 (s, 2H), 2.86 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O2S, [M]+ 289.3530; Found 289.3516; 13C NMR (150 MHz, DMSO): δ171.0, 159.4, 158.6, 150.4, 146.8, 138.7, 130.2, 122.5, 121.8, 118.2, 114.9, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O2S, C, 58.11; H, 5.23; N, 14.52; Found C, 58.04; H, 5.11; N, 14.43.
4.2.10. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(4-hydroxybenzylidene) Acetohydrazide (10) Yield: 85%. m. p. 213°C; white powder; 1H NMR (600 MHz, DMSO): δ 11.10 (s, 1H), 9.89 (s, 1H), 8.37 (s, 1H), 7.37-7.31 (s, J = 7.5 Hz, 2H), 6.85-6.84 (s, J = 7.5 Hz, 2H), 3.83 (s, 2H), 2.83 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O2S, [M]+ 289.3530; Found 289.3520; 13C NMR (150 MHz, DMSO): δ171.0, 160.8, 159.4, 150.4, 144.1, 130.6, 130.6, 126.3, 122.5, 116.0, 116.0, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O2S, C, 58.11; H, 5.23; N, 14.52; Found C, 58.06; H, 5.18; N, 14.44.
4.2.11. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2,3,4-trihydroxybenzylidene) Acetohydrazide (11) Yield: 95%. m. p. 213°C; yellow crystals; 1H NMR (600 MHz, DMSO): δ 11.40 (s, 1H), 11.20 (s, 1H), 10.40 (s, 1H), 9.50 (s, 1H), 11.10 (s, 1H), 6.42 (s, 2H), 3.83 (s, 2H), 2.82 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O4S, [M]+ 321.3510; Found 321.3502; 13C NMR (150 MHz, DMSO): δ171.0, 159.4, 153.1, 152.4, 150.4, 146.8, 136.1, 126.4, 122.5, 112.5, 110.0, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O4S, C, 52.33; H, 4.71; N, 13.08; Found C, 52.24; H, 4.60; N, 13.01.
4.2.12. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2-nitrobenzylidene) Acetohydrazide (12) Yield: 76%. m. p. 167°C; yellow crystals; 1H NMR (600 MHz, DMSO): δ 11.30 (s, 1H), 10.50 (s, 1H), 8.35 (d, J = 1.0 Hz, 1H), 8.10 (ddd, J = 7.5 Hz, 1H), 7.93 (d, J = 7.5 Hz, 1H), 7.69 (d, J = 7.5 Hz, 1H), 3.51 (s, 2H), 2.84 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14N4O3S, [M]+ 318.3510; Found 318.3502; 13C NMR (150 MHz, DMSO):δ171.0, 159.4, 150.4, 147.8, 143.3, 134.9, 131.9, 130.1, 128.4, 124.0, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14N4O3S, C, 52.82; H, 4.43; N, 17.60; Found C, 52.74; H, 4.36; N, 17.51.
4.2.13. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(3-nitrobenzylidene) Acetohydrazide (13) Yield: 86%. m. p. 221°C; brown; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 9.40 (s, 1H), 8.48 (d, J = 2.0 Hz, 1H), 8.37 (d, J = 2.0 Hz, 1H), 8.09 (dd, J = 7.5 Hz, 1H), 7.72 (t, J = 7.5 Hz, 1H), 3.84 (s, 2H), 2.83 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14N4O3S, [M]+ 318.3510; Found 318.3502; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 148.0, 142.8, 134.6, 132.5, 129.7, 126.2, 121.6, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14N4O3S, C, 52.82; H, 4.43; N, 17.60; Found C, 52.74; H, 4.36; N, 17.53.
4.2.14. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(4-nitrobenzylidene) Acetohydrazide (14) Yield: 99%. m. p. 167°C; yellow powder; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 8.37 (s, 1H), 7.90 (d, J = 8.0 Hz, 2H), 6.96 (d, J = 8.0 Hz, 2H), 3.53 (s, 2H), 2.86 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14N4O3S, [M]+ 318.3510; Found 318.3501; 13C NMR (150 MHz, DMS): δ 172.0, 159.5, 150.5, 150.2, 144.1, 139.8, 124.2, 124.2, 124.0, 124.0, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14N4O3S, C, 52.82; H, 4.43; N, 17.60; Found C, 52.76; H, 4.36; N, 17.53.
4.2.15. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2-hydroxy-5-methoxybenzylidene) Acetohydrazide (15) Yield: 83%. m. p. 89°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.20 (s, 1H), 9.30 (s, 1H), 8.40 (s, 1H), 7.80 (d, J = 6.0 Hz, 1H), 7.24-7.20 (m, 1H), 6.83 (d, J = 1.0 Hz, 1H), 3.85 (s, 3H), 3.53 (s, 2H), 2.43 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C15H17N3O3S, [M]+ 319.3790; Found 319.3782; 13C NMR (150 MHz, DMSO): δ 171.1, 159.3, 153.4, 153.3, 150.4, 146.0, 122.5, 119.5, 118.0, 117.2, 113.5, 55.8, 36.4, 19.6, 10.6; Anal. Calcd for C15H17N3O3S, C, 56.41; H, 5.37; N, 13.16; Found C, 56.32; H, 5.30; N, 13.10.
4.2.16. (E)-N′-(3-Bromo-4-fluorobenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (16) Yield: 97%. m. p. 255°C; yellow powder; 1H NMR (600 MHz, DMSO): δ 10.60 (s, 1H), 8.37 (s, 1H), 7.58 (s, 1H), 7.27 (dd, J = 6.0, 7.5 Hz, 1H), 6.97 (dd, J = 6.0, 7.5 Hz, 1H), 3.51 (s, 2H), 2.84 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H13BrFN3OS, [M]+ 370.2404; Found 370.2396; 13C NMR (150 MHz, DMSO): δ 171.0, 167.7, 159.4, 150.4, 146.8, 134.3, 131.5, 129.8, 122.5,117.8, 110.2, 36.4, 19.6, 10.6; Anal. Calcd for C14H13BrFN3OS, C, 45.42; H, 3.54; N, 11.35; Found C, 45.33; H, 3.49; N, 11.31.
4.2.17. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2,4,6-trihydroxybenzylidene) Acetohydrazide (17) Yield: 96%. m. p. 141°C; yellow powder; 1H NMR (600 MHz, DMSO): δ 11.70 (s, 1H), 10.85 (s, 1H), 10.40 (s, 1H), 9.650 (s, 1H), 8.35 (s, 1H), 6.54 (s, 2H), 3.83 (s, 2H), 2.84 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H15N3O4S, [M]+ 321.3510; Found 321.3523; 13C NMR (150 MHz, DMSO): δ 171.0, 163.9, 163.9, 163.6, 159.4, 150.4, 143.3, 122.5, 106.2, 96.3, 96.3, 36.4, 19.6, 10.6; Anal. Calcd for C14H15N3O4S, C, 52.33; H, 4.71; N, 13.08; Found C, 52.25; H, 4.66; N, 13.02.
4.2.18. (E)-N′-(3-Chlorobenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (18) Yield: 77%. m. p. 141°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.80 (s, 1H), 8.35 (s, 1H), 7.92 (d, J = 2.0 Hz, 1H), 7.65 (d, J = 2.0 Hz, 1H), 7.20 (d, J = 7.5 Hz, 1H), 7.72 (d, J = 7.5 Hz, 1H), 3.53 (s, 2H), 2.86 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14ClN3OS, [M]+ 307.7960; Found 307.7948; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 146.8, 135.1, 134.4, 131.1, 130.2, 127.3, 127.1, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14ClN3OS, C, 54.63; H, 4.58; N, 13.65; Found C, 54.56; H, 4.49; N, 13.58.
4.2.19. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(pyridin-3-ylmethylene) Acetohydrazide (19) Yield: 87%. m. p. 88°C; yellow powder; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 9.08 (d, J = 2.0 Hz, 1H), 8.71 (dd, J = 5.0, 2.0 Hz, 1H), 8.42 (dt, J = 8.0, 2.0 Hz, 1H), 8.34 (s, 1H), 7.42 (dd, J = 8.0, 5.0 Hz, 1H), 3.82 (s, 2H), 2.83 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C13H14N4OS, [M]+ 274.3420; Found 274.3411; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 151.9, 150.4, 149.0, 143.3, 133.7, 130.4, 123.9, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C13H14N4OS, C, 56.92; H, 5.14; N, 20.42; Found C, 56.84; H, 5.19; N, 20.34.
4.2.20. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(pyridin-4-ylmethylene) Acetohydrazide (20) Yield: 87%. m. p. 98°C; white powder; 1H NMR (600 MHz, DMSO): δ 10.30 (s, 1H), 8.62 (s, 1H), 8.22 (d, J = 6.0 Hz, 2H), 7.57 (d, J = 6.0 Hz, 2H), 3.53 (s, 2H), 2.84 (s, 3H), 2.32 (s, 3H); HR-EI-MS: m/z calcd for C13H14N4OS, [M]+ 274.3420; Found 274.3412; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 149.4, 149.4, 146.8, 144.3, 120.4, 120.4, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C13H14N4OS, C, 56.92; H, 5.14; N, 20.42; Found C, 56.84; H, 5.10; N, 20.36.
4.2.21. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(2-fluorobenzylidene) Acetohydrazide (21) Yield: 83%. m. p. 105°C; white milky; 1H NMR (600 MHz, DMSO): δ 10.40 (s, 1H), 8.40 (s, 1H), 8.20 (d, J = 7.0 Hz, 1H), 7.53-7.46 (m, 1H), 7.28 (d, J = 7.0 Hz, 1H), 7.22 (td, J = 7.5, 2. Hz, 1H), 3.81 (s, 2H), 2.86 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14FN3OS, [M]+ 291.3444; Found 291.3436; 13C NMR (150 MHz, DMSO): δ 171.0, 159.6, 159.4, 150.4, 143.3, 132.6, 130.8, 124.4, 118.2, 115.6, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14FN3OS, C, 57.72; H, 4.84; N, 14.42; Found C, 57.65; H, 4.80; N, 14.36.
4.2.22. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(4-fluorobenzylidene) Acetohydrazide (22) Yield: 85%. m. p. 97°C; white crystals; 1H NMR (600 MHz, DMSO): δ 10.36 (s, 1H), 8.35 (s, 1H), 7.90 (t, J = 7.0 Hz, 2H), 7.08 (d, J = 7.0 Hz, 2H), 3.52 (s, 2H), 2.45 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14FN3OS, [M]+ 291.3444; Found 291.3431; 13C NMR (150 MHz, DMSO): δ 171.0, 165.2, 159.4, 150.4, 144.1, 130.8, 130.8, 129.3, 115.6, 115.6, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14FN3OS, C, 57.72; H, 4.84; N, 14.42; Found C, 57.66; H, 4.80; N, 14.38.
4.2.23. (E)-2-(2,5-Dimethylthiazol-4-yl)-N′-(3-fluorobenzylidene) Acetohydrazide (23) Yield: 84%. m. p. 97°C; white crystals; 1H NMR (600 MHz, DMSO): δ 10.20 (s, 1H), 8.38 (s, 1H), 7.59 (td, J = 7.6, 5.7 Hz, 1H), 7.48-7.39 (m, 2H), 7.19-7.13 (m, 1H), 3.54 (s, 2H), 2.52 (s, 3H), 2.30 (s, 3H); HR-EI-MS: m/z calcd for C14H14FN3OS, [M]+ 291.3444; Found 291.3436; 13C NMR (150 MHz, DMSO): δ 171.0, 165.2, 159.4, 150.4, 144.1, 130.8, 130.8, 129.3, 115.6, 115.6, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14FN3OS, C, 57.72; H, 4.84; N, 14.42; Found C, 57.67; H, 4.81; N, 14.46.
4.2.24. (E)-N′-(2-Chlorobenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (24) Yield: 75%. m. p. 127°C; white crystals; 1H NMR (600 MHz, DMSO): δ 10.20 (s, 1H), 8.35 (s, 1H), 8.20 (d, J = 2.0 Hz, 1H), 7.52-7.44 (m, 2H), 7.35 (td, J = 7.5, 2.0 Hz, 1H), 3.55 (s, 2H), 2.84 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14ClN3OS, [M]+ 307.7960; Found 307.7952; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 138.7, 134.7, 133.9, 132.4, 130.1, 127.2, 126.9, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14ClN3OS, C, 54.63; H, 4.58; N, 13.65; Found C, 54.54; H, 4.54; N, 13.60.
4.2.25. (E)-N′-(4-Chlorobenzylidene)-2-(2,5-dimethylthiazol-4-yl) Acetohydrazide (25) Yield: 95%. m. p. 120°C; yellow crystals; 1H NMR (600 MHz, DMSO): δ 11.75 (s, 1H), 8.37 (s, 1H), 7.85 (d, J = 7.5 Hz, 2H),), 7.50 (d, J = 7.5 Hz, 2H), 3.46 (s, 2H), 2.86 (s, 3H), 2.33 (s, 3H); HR-EI-MS: m/z calcd for C14H14ClN3OS, [M]+ 307.7960; Found 307.7972; 13C NMR (150 MHz, DMSO): δ 171.0, 159.4, 150.4, 144.1, 136.6, 131.8, 130.6, 130.6, 128.9, 128.9, 122.5, 36.4, 19.6, 10.6; Anal. Calcd for C14H14ClN3OS, C, 54.63; H, 4.58; N, 13.65; Found C, 54.58; H, 4.54; N, 13.60.