## 3 Experimental
### Chemistry
#### 3.1.1 Synthesis of Tetra-Substituted Pyridine Derivatives (**4a-f** and **6a-f**)
Dark yellow solid, (76% yield), mp 181-183 \({}^{\circ}\)C; IR (KBr) \(\
u_{\rm max}\) 3362, 3218 (NH\({}_{2}\)), 2213 (CN), 1712 (C=O) cm\({}^{-1}\); \({}^{1}\)H NMR (DMSO-\(d_{6}\)) \(\delta\) 1.02 (t, J = 7.2 Hz, 3H, CH\({}_{3}\)), 4.14 (q, J = 7.2 Hz, 2H, CH\({}_{2}\)), 6.98 (s, br, 2H, NH\({}_{2}\)), 7.17-7.84 (m, 14H, Ar-H), 8.17 (s, 1H, Pyridine-H5); MS \(m/z\) (%) 521 (M\({}^{+}\), 23), 519 (M\({}^{+}\), 8), 397 (32), 316(60), 191 (55), 127 (51), 85 (47), 57 (100). Anal. Calcd. for C\({}_{30}\)H\({}_{22}\)ClN\({}_{5}\)O\({}_{2}\) (519.99): C, 69.30; H, 4.26; N, 13.47. Found: C, 69.16; H, 4.18; N, 13.28%. _Ethyl 3-(6-amino-5-cyano-4-(2,4-dichlorophenyl)pyridin-2-yl)-1,5-diphenyl-\(1H\)-pyrazole-4-carboxylate_ **(4f)**. Yellow solid, (75% yield), mp 197-199 \({}^{\circ}\)C; IR (KBr) \(\
u_{\rm max}\) 3367, 3215 (NH\({}_{2}\)), 2214 (CN), 1714 (C=O) cm\({}^{-1}\); \({}^{1}\)H NMR (DMSO-\(d_{6}\)) 8 1.04 (t, \(J\) = 7.2 Hz, 3H, CH\({}_{3}\)), 4.15 (q, \(J\) = 7.2 Hz, 2H, CH\({}_{2}\)), 7.06 (s, br, 2H, NH\({}_{2}\)), 7.28-7.85 (m, 13H, Ar-H), 8.14 (s, 1H, Pyridine-H5); MS \(m/z\) (%) 554 (M\({}^{+}\), 100), 316 (77), 281 (41), 193 (71), 105 (33), 58 (72). Anal. Calcd. for C\({}_{30}\)H\({}_{21}\)Cl\({}_{2}\)N\({}_{5}\)O\({}_{2}\) (554.43): C, 64.99; H, 3.82; N, 12.63. Found: C, 64.80; H, 3.61; N, 12.44%. _Ethyl 3-(5-acetyl-6-oxo-4-phenyl-1,6-dihydropyridin-2-yl)-1,5-diphenyl-\(1H\)-pyrazole-4-carboxylate_ **(6a)**. Brown solid, (68% yield), mp 186-188 \({}^{\circ}\)C; IR (KBr) \(\
u_{\rm max}\) 3367 (NH), 1722, 1690, 1657 (3C=O) cm\({}^{-1}\); \({}^{1}\)H NMR (DMSO-\(d_{6}\)) 8 1.03 (t, \(J\) = 7.2 Hz, 3H, CH\({}_{3}\)), 2.58 (s, 3H, CH\({}_{3}\)), 4.12 (q, \(J\) = 7.2 Hz, 2H, CH\({}_{2}\)), 7.24-7.49 (m, 15H, Ar-H), 7.77 (s, 1H, Pyridine-H5), 9.63 (s, br, 1H, NH); MS \(m/z\) (%) 503 (M\({}^{+}\), 48), 458 (27), 334 (52), 232 (46), 99 (54), 57 (68), 43 (100). Anal. Calcd. for C\({}_{31}\)H\({}_{25}\)N\({}_{3}\)O\({}_{4}\) (503.56): C, 73.94; H, 5.00; N, 8.34. Found: C, 73.73; H, 4.86; N, 8.17%. _Ethyl 3-(5-acetyl-6-oxo-4-(p-tolyl)-1,6-dihydropyridin-2-yl)-1,5-diphenyl-\(1H\)-pyrazole-4-carboxylate_ **(6b)**. Brown solid, (66% yield), mp 134-136 \({}^{\circ}\)C; IR (KBr) \(\
u_{\rm max}\) 3409 (NH), 1718, 1681, 1662 (3C=O) cm\({}^{-1}\); \({}^{1}\)H NMR (DMSO-\(d_{6}\)) 8 1.02 (t, \(J\) = 7.2 Hz, 3H, CH\({}_{3}\)), 2.35 (s, 3H, CH\({}_{3}\)), 2.56 (s, 3H, CH\({}_{3}\)), 4.11 (q, \(J\) = 7.2 Hz, 2H, CH\({}_{2}\)), 7.19-7.49 (m, 14H, Ar-H), ), 7.79 (s, 1H, Pyridine-H5), 9.81 (s, br, 1H, NH); MS \(m/z\) (%) 517(M\({}^{+}\), 23), 385 (33), 294 (38), 147 (50), 120 (100), 76 (62). Anal. Calcd. for C\({}_{32}\)H\({}_{27}\)N\({}_{3}\)O\({}_{4}\) (517.59): C, 74.26; H, 5.26; N, 8.12. Found: C, 74.20; H, 5.14; N, 8.03%. _Ethyl 3-(5-acetyl-4-(4-methoxyphenylyl)-6-oxo-1,6-dihydropyridin-2-yl)-1,5-diphenyl-\(1H\)-pyrazole-4-carboxylate_ **(6c)**. Pale brown solid, (67% yield), mp 141-143 \({}^{\circ}\)C; IR (KBr) \(\
u_{\rm max}\) 3423 (NH), 1715, 1687, 1660 (3C=O) cm\({}^{-1}\); \({}^{1}\)H NMR (DMSO-\(d_{6}\)) 8 1.00 (t, \(J\) = 7.2 Hz, 3H, CH\({}_{3}\)), 2.57 (s, 3H, CH\({}_{3}\)), 3.77 (s, 3H, OCH\({}_{3}\)), 4.01 (q, \(J\) = 7.2 Hz, 2H, CH\({}_{2}\)), 7.16-7.54 (m, 14H, Ar-H), ), 7.74 (s, 1H, Pyridine-H5), 9.80 (s, br, 1H, NH); MS \(m/z\) (%) 533 (M\({}^{+}\), 14), 423 (37), 313 (51), 279 (100), 105 (36), 76 (43). Anal. Calcd. for C\({}_{32}\)H\({}_{27}\)N\({}_{3}\)O\({}_{5}\) (533.58): C, 72.03; H, 5.10; N, 7.88. Found: C, 71.85; H, 5.02; N, 7.63%. _Ethyl 3-(5-acetyl-4-(4-(dimethylamino)phenyl)-6-oxo-1,6-dihydropyridin-2-yl)-1,5-diphenyl-\(1H\)-pyrazole-4-carboxylate_ **(6d)**.