College of Science

     This  thesis consists of the synthesis of new liquid crystalline compounds 2-thiobutanoyl-5-[4-(4´-methoxybenzylideneamino)phenyl]1,3,4-oxadiazole 1_e, 4-[4´-methoxyben- zylideneamion)benzoyloxy]propylbenzoate 2_d and two new homologous series derived from 2,5-bis-[4-amino phenyl]-1,3,4-oxadiazole 3_d, these are 2,5-bis-[4-(4´-alkoxybenzylideneamino)phenyl]-1,3,4-xadiazole 3_e1-3_i1 and 2,5-bis-[4-(4´-alkoxybenzanilide)phenyl]-1,3,4-oxadiazole 3_e2-3_i2.(3_{e2,f2,g2,h2, i2}

Derivatives of 1,3,4-thiadiazole ring show biological activities against different species of microbes, therefore mono- and poly-nuclear complexes of dithiocarbamate derivatives of 2-amino-5-mercapto-1,3,4-thiadiazole (AMT), have been prepared in an attempt to show the effect of introducing two centers in the structure of the ligand (NaMTD), as well as to investigate the coordination behavior of the ligand toward both transition metals and to compare the biological activity of the complexes with that of the ligand.Dithiocarbamate derivatives of AMT (NaMTD), were

The scheme of this work involves synthesis of different heterocyclic rings utilizing the two different reactive sites of 2-amino-5-mercapto-1,3,4-thiadiazole.This work is divided into four different parts:

   First Part:  Involved synthesizing two new fused rings derived from the reaction of –NH₂ group of the starting material with different organic reagents. The following reaction steps shown in scheme [I] are of a feasible strategy: