In this research work new heterocyclic derivatives containing triazolidine have been prepared. The most available (mesalazine) has been used with benzaldehyde to get the starting material to prepare the alkyl triazolidine. All the synthesized compounds have been identified using FT-IR and 1H-NMR spectrum. (Scheme 1) shows that, from simple and available material mesalazine with benzaldehyde in basic media compound (H1) containing Schiff base prepared. A ring closer reaction has been made to compound W using ethylene glycol and hydrazine to get (H2) compound. The nitrogen atom of compound (H2) also alkylated by chloroacetic acid to give (H4) compound then H4 compound reacted with thionyl chloride to get acetyl chloride (H5compound). Compound H5 treated with amino acid (glycine) to get (H6) compound. (H7) Compound has been synthesis by reacting (H6) compound with aromatic aldehyde in the presence of acetic anhydride to get Oxazole ring (H7 compound). Also, (H2) compound reacted with malic anhydride to prepare triazolidine diacetic acid derivative H3 compound. These synthesized compounds had also been assessed by (DPPH) method, the compounds (H1-H7) evaluated for their antimicrobial activity and antioxidant activity, the compounds have strong antioxidant activity comparable to that of the well known (ascorbic acid) (IC50=31.95 μg/mL) used.