Synthesis of new hetrocyclic compounds derived from 2-amino-5-mercapto-1,3,4-thiadaiazole.

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: Scheme [I] Second Part: Involved synthesizing oxazole, tetrazole and thiazolidinone erivatives from the reaction of -NH2 group of the starting material with different organic reagents. Scheme [II] shows steps of the reactions: mentioned in the original abstract Scheme [II] Third Part: Involved synthesizing of benzimidazole, pyrazolone, 1,3,4-oxadiazole, dihydro-pyridazin-3,6-dione and 1,2,4- riazole derivatives from the reaction of -SH group of the starting material with different organic reagents, the following reaction steps are shown in scheme [III] : mentioned in the original abstract Scheme [III] Continued: mentioned in the original abstract Scheme [III] Fourth Part: This part deals with the study of antibacterial and antifungal activity of some of the synthesized compounds and comparing these activities with that of the starting material. These activities were determined in vitro using disc diffusion method against three pathogenic strains of bacteria (Escherichia coli, Klebsiella pneumoniae, and Proteus vulgaris), and two pathogenic strains of fungus (Candida albicans and Aspergillus niger). The results revealed that some of these compounds showed measurable activity as shown in Table (3-7).