ABSTRACT1,3,4-oxadiazole-5-thion ring(2) successfully formed at position six of 2-methylphenol and five of their thioalkyl(3a-e). Furthermore 6-(5-(Aryl)-1,3,4-oxadiazol-2-yl)-2-methylphenol (5a-i) were formed at position six by two method. The first method was from cyclization their correspondinghydrazones(4a-e) of 2-hydroxy-3-methylbenzohydrazide (1)using bromine in glacial acetic acid.The second method was from cyclization the hydrazide with aryl carboxylic acid in the presence of phosphorusoxy chloride. The newly synthesized compounds were characterized from their IR, NMR and mass spectra. The antioxidant properties of these compounds were screened by 2,2-Diphenyl-1-picrylhydrazide (DPPH) and ferric reducing antioxidant power (FRAP) assays. Compound (4d) and (5h) exhibited significant antioxidant properties in both assays, compared to ascorbic acid, while compound (4e) exhibited slightly less antioxidant properties than ascorbic acid. Antibacterial activity was tested for the twenty one compounds against eight microorganisms (gram negative and gram positive). Compound (4d)and (5d) exhibited significant antibacterial activities compared to Amoxicillin and Kanamycin as antibiotic standards.

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The compound 2,2'-(((1H-benzo(d)imidazol-2-yl)methyl)azanediyl)bis(ethan-1-ol) was reacted with benzyl bromide to afford compound (1) which used as row material to prepare a series of compounds through condensation reaction, the starting compound were reacted with tosyl chloride to protect the OH group  to afford compound 2, then reacted benzyl bromide to produce compound (2), then the compound (2) treated with three compounds ( 2-mercaptobenzthiazole, 2-mercaptobenimidazol and 2-chloromethyl benzimidazole) to form compounds 3a,b, 4a,b and 5a,b respectively. In the another step the click reaction of compound 2,2'-(((1H-benzo(d)imidazol-2-yl)methyl)azanediyl)bis(ethan-1-ol) with Propargyl bromide produce compound  6  which reacted with sodium azide or benzyl azide to afford the compounds 7 and 8. The synthesized compounds were characterized and measured the physical properties via the FT-IR, HNMR, besides to the CHN analysis. These newly compounds were screened their antibacterial and antifungal activity. Compounds 1, 2a and 8 showed significant   antibacterial activity as well these compounds exhibited either low or moderated antifungal activity.

Reducing of ethyl 4-((2-hydroxy-3-methoxybenzylidene)amino)benzoate (1) afford ethyl 4-((2-hydroxy-3-methoxybenzyl)amino)benzoate (2). Reaction of this compound with Vilsmeier reagent affords novel 2-chloro-[1,3] benzoxazine ring (3). The corresponding acid hydrazide of compound 3 was synthesized from reaction of compound (3) with hydrazine hydrate. Newly series of hydrazones (5a–i) were synthesized from reaction of acid hydrazide with various aryl aldehydes. Antibacterial activity of the hydrazones was secerned utilizing gram-negative and gram-positive bacteria. Compound (5b) and (5c) exhibited significant antibacterial ability against both gram-negative and gram-positive bacteria, while the compounds (5a) showed mild antibacterial activity. Compounds (5d–i) did not display notable activity. The molecular docking of synthesised compounds were tested inside the pocket of bacterial gyrase enzyme target site by using MOE 2015 software, which acts as Adenosine triphosphate (ATP)-binding domain bacterial gyrase enzyme pocket and novobiocin was used as reference.