Quinazolin-4-Methyl Synthesis

2-((6,8-dibromo-2-(4-chlorophenyl)quinazolin-4-yloxy)methyl)-5-methyl-1,3,4-oxadiazole (IX) :
A mixture of the hydrazide VII (0.01 mol) and acetic anhydride (30mL) was refluxed for 6h. The precipitated solid formed upon cooling, was filtered and recrystallized from ethanol, m.p. 155oC, 80% yield. Analysis calculated for C18H11Br2ClN4O2; Calcd.: %C, 42.34; H, 2.17; N, 10.97, Found: % C, 42.30; H, 2.14; N, 10.90. IR: υmax./cm-1 3000 (C-H aromatic), 1610 (C=N) and at 1600 (C=C). 1H-NMR (DMSO-d6, ppm): δ 2.6 (s, 3H, CH3), 5.4 (s, 2H, OCH2) and 7.5-8.2 (m, 6H, aromatic-H). 13C NMR (DMSO-d6): 185, 164, 162, 150, 141, 135, 133, 129, 128, 124, 123, 121, 117, 72, 21. MS: m/z = 510
N'-(2-(6,8-dibromo-2-(4-chlorophenyl)quinazolin-4-yloxy)acetyl)isonicotinohydrazide (X) :
A mixture of hydrazide VII (0.01 mol) and isonicotinoyl chloride (0.015 mol) in dimethyl formamide (25 ml) was heated
The reaction mixture was cooled, poured onto crushed (100 ml) ice . The solid was filtered, washed with water, dried and crystallized from methanol, m.p. 180oC, 80% yield. Analysis calculated for C23H14Br2Cl2N4O3; Calcd.: %C, 44.19; H, 2.26; N, 8.96, Found: % C, 44.15; H, 2.24; N, 8.64. IR: υmax./cm-1 3300 (NH), 3020 (C-H aromatic), 1760 (C=O), 1720 (C=O), 1650 (C=N) and at 1610 (C=C) . 1H-NMR (DMSO-d6, ppm): 4.5 (s, 2H, OCH2) and 7.5-8.0 (m, 10H, aromatic-H), 10.0 (1H, s, NH, exchangeable with D2O) and 10.2 (1H, s, NH, exchangeable with D2O). 13C NMR (DMSO-d6): 182,165 164,162, 152 , 141,138, 134, 132, 131, 129, 128, 124, 123, 121, 119, 68. MS: m/z = 624

2-(2-(6,8-dibromo-2-(4-chlorophenyl)quinazolin-4-yloxy)acetyl)-N-(methyl or substituted phenyl) hydrazinecarbothioamide (XIII a-c) :

General method: a mixture of hydrazide VII (0.01 mol), the