## 3 Experimental Section
### Synthesis of 1-(2-[N-(4-methoxybenzylidene)-hydrazino]-4-methylthiazol-5-yl]-ethanone
230-232 \({}^{\circ}\)C; \(\delta_{\rm H}\)(DMSO-\(d_{6}\)): 2.35, 2.40, 2.48, 2.57 (4s, 12H, 4 CH\({}_{3}\)), 3.79 (s, 3H, OCH\({}_{3}\)), 7.02-7.06 (d, 2H, \(J\) = 16 Hz, Ar-H), 7.65-7.69 (d, 2H, \(J\) = 16 Hz, Ar-H), 8.08 (s, 1H, N=CH), 8.19, 9.27 (2 brs, 2H, 2 NH) ppm; \"a \({}^{13}\)C NMR spectrum could not be obtained due to insolubility; IR (KBr): \(v\) 3412, 3237 (2 NH), 3036, 2939 (C-H), 1703  
**Compound 16:**  
Yellow solid, 72% yield; m.p. 228-230 \({}^{\circ}\)C; \(\delta_{\rm H}\)(DMSO-\(d_{6}\)): 2.51, 2.66 (2s, 6H, 2 CH\({}_{3}\)), 3.81 (s, 3H, OCH\({}_{3}\)), 7.04 (s, 1H, thiazole- H5), 7.06-8.36 (m, 9H, Ar-H), 8.50 (s, 1H, N=CH), 9.65, 10.76 (2 brs, 2H, 2 NH) ppm; \(\delta_{\rm C}\) (DMSO-\(d_{6}\)): 14.4, 20.7 (CH\({}_{3}\)), 56.8 (OCH\({}_{3}\)), 102.9, 113.3, 115.0, 118.9, 123.9, 130.0, 131.8, 138.8, 140.8, 145.0, 152.0, 152.5, 159.8, 163.4, 168.7 (Ar-C or C=N) ppm; IR (KBr): \(v\) 3433, 3239 (2 NH), 3001, 2938 (C-H), 1613 (C=N), 1512, 1257, 1172, 1026 cm\({}^{-1}\); MS \(m/z\) (%): 462 (M\({}^{+}\)), 287, 246, 176, 134 (100), 120, 91, 77, 67. Anal. Calcd for C\({}_{23}\)H\({}_{22}\)N\({}_{6}\)OS\({}_{2}\) (462.59): C, 59.72; H, 4.79; N, 18.17. Found: C, 59.79; H, 4.58; N, 18.03%. **Synthesis of thiazole derivative 18:**  
Anhydroous sodium acetate (0.33 g, 4 mmol) was added to a mixture of compound **7** (0.362 g, 1 mmol) and ethyl chloroacetate **17** (0.122 g, 1 mmol) in AcOH (20 mL). The mixture was refluxed for 4h, then the solid product was recrystallized from EtOH to afford the thiazole derivative **18** as yellow solid, 69% yield; m.p. 235-237 \({}^{\circ}\)C \(\delta_{\rm H}\)(DMSO-\(d_{6}\)): 2.41 (s, 3H, CH\({}_{3}\)), 2.48 (s, 3H, CH\({}_{3}\)), 3.81 (s, 3H, OCH\({}_{3}\)), 4.14 (s, 2H, CH\({}_{2}\)), 6.97-7.00 (d, 2H, \(J\) = 12 Hz, Ar-H),7.65-7.68 (d, 2H, \(J\) = 12 Hz, Ar-H), 8.16 (s, 1H, N=CH), 9.18, 10.38 (2 brs, 2H, 2 NH) ppm; \(\delta_{\rm C}\) (DMSO-\(d_{6}\)): 10.9, 14.5 (CH\({}_{3}\)), 36.8 (CH\({}_{2}\)), 56.9 (OCH\({}_{3}\)), 103.3, 114.4, 116.4, 123.2, 130.5, 131.4, 136.8, 1459, 147.0, 159.5 (Ar-C or C=N), 176.7 (C=O) ppm; IR (KBr): \(v\) 3417, 3222 (2 NH), 3026, 2918 (C-H), 1692 (C=O), 1606 (C=N), 1530, 1248, 1148, 1029 cm\({}^{-1}\); MS \(m/z\) (%): 402 (M\({}^{+}\)), 312 (100), 215, 138, 78, 63. Anal. Calcd for C\({}_{17}\)H\({}_{18}\)N\({}_{6}\)O\({}_{2}\)S\({}_{2}\) (402.49): C, 50.73; H, 4.51; N, 20.88. Found: C, 50.62; H, 4.44; N, 20.63%. **Synthesis of thiazole derivative 20. **  
A mixture of dimethyl acetylene dicarboxylate **19** (0.142 g, 1 mmol) and compound **7** (0.362 g, 1 mmol) in dry methanol (20 mL) was refluxed for 2h the formed product was recrystallized from ethanol to give pure product **20** as yellow solid, 70% yield; m.p. 270-272 \({}^{\circ}\)C (DMF); \(\delta_{\rm H}\)(DMSO-\(d_{6}\)): 2.42 (s, 3H, CH\({}_{3}\)), 2.45 (s, 3H, CH\({}_{3}\)), 3.75 (s, 3H, COOCH\({}_{3}\)), 3.80 (s, 3H, OCH\({}_{3}\)), 6.63 (s, 1H, =CH-COOCH\({}_{3}\)), 7.0-7.03 (d, 2H, \(J\) = 12 Hz, Ar-H), 7.61-7.64 (d, 2H, \(J\) =12 Hz, Ar-H), 8.12 (s, 1H, N=CH), 8.29, 9.98 (2 brs, 2H, 2 NH) ppm; \(\delta_{\rm C}\) (DMSO-\(d_{6}\)): 9.0, 25.2 (CH\({}_{3}\)), 46.1, 56.8 (OCH\({}_{3}\)), 115.5, 117.5, 118.7, 119.8, 124.6, 129.3, 129.8, 135.3, 138.1, 153.0, 154.0, 162.7 (Ar-C or C=N), 169.2, 173.1 (C=O) ppm; IR (KBr): \(v\) 3433, 3194 (2 NH), 3055, 2900 (C-H), 1705, 1691 (2C=O), 1600 (C=N), 1504, 1311, 1242, 1165 cm\({}^{-1}\); MS \(m/z\) (%): 472 (M\({}^{+}\)), 339, 256, 153, 133 (100), 103, 91, 77, 59. Anal. Calcd for C\({}_{20}\)H\({}_{20}\)N\({}_{6}\)O\({}_{4}\)S\({}_{2}\) (472.54): C, 50.83; H, 4.27; N, 17.78. Found: C, 50.64; H, 4.36; N, 17.61%.