karbala journal of pharmaceutical sciences

This paper contains the synthesis of some new bis heterocyclic compounds starting from the esters of bis carboxylic acid which then converted to its hydrazide [1-5] then to bis1,3,4-Oxadiazole derivatives [6-10] beside bis maleamic acid derivatives [11-15] and finally with bis maleimides [16-20] .
Preparing of bis ester by usual esterification of substituted bis aliphatic carboxylic acid with absolute ethanol in acidic medium , then has converted to its substituted bis aliphatic carboxylic acid hydrazide by reacting it with hydrazine hydrate . The derivatives bis-1,3,4-Oxadiazole have synthesized by cyclization of bis aliphatic carboxylic acid hydrazide with 4- amino benzoic acid in presence of phosphoric acid 85% .
So ,the bis- maleamic acids have been synthesized by the reaction of compounds [6-10] with maleic anhydride in diethyl ether. Also bis maleimides are synthesized by cyclization of bis maleamic acids derivatives by using acetic acid anhydride and anhydrous sodium acetate. The synthesized compounds were identified by spectral methods UV,FT-IR and H1- NMR beside melting point and the purity was determined by using ( TLC ) and some of its physical properties were measured . Some of these compounds are tested against four strains of bacteria ( Staph. aurease , E. coli ,Sal. thph and Ps. aeruginosa)

Some of hydrazone derivatives[2a-e] were prepared from the reaction of 2-phenyl acetic acid hydrazide[1] with different substituted benzaldehydes, then cyclization of hydrazones in glacial acetic acid and lead dioxide resulted into the formation of new 1,3,4-Oxadiazole derivatives [3a-e], Symmetrical 4-amino Triazole derivatives [5a-e] were prepared from reaction of 3,5-dibenzyl-4-amino 1,2,4-Triazole[4] with different substituted benzaldehydes to product new series of different Schiff bases [5a-e]. The prepared compounds were characterized by FT-IR, and UV spectroscopy, the melting points were determined and the purity and reaction time was checked by TLC, the biological activity was evaluated against different types of bacteria.