Synthesis of some new Thiazolidine and 1,3,4-Oxadiazole Derived from L-cysteine and Study of Their Biological Activity as Antioxidant and Breast Cancer

The study firstly included the synthesis of aldehyde derivatives by reacting p-hydroxy benzaldehyde with ethyl chloroacetate to prepare compound (A), then producing the thiazolidine derivatives by condensing compound (A) with cysteine to obtain (AT). Thiazolidines possess two types of isomers (diastereomers) that are difficult to separate ( cis-(2R,4R) and trans-(2S,2R)). Due to the presence of chiral atoms, an isomer cis/ trans percentages were powerfully dependent on a solvent. The compound (AT) reacts with acetic anhydride for the synthesis of the compound (ATA), then it reacts with hydrazine hydrate to prepare the 3-acetyl-2-[4-(2-hydrazinyl-2-oxoethoxy) phenyl]thiazolidine-4-carboxylic acid (ATAH), which is the basic unit in the synthesis of 1,3,4-oxadiazoes, as the compound (ATAH) reacts with carboxylic acid derivatives in the presence of phosphoryl chloride to synthesis 1,3,4-oxadiazole derivatives (ATAO1-4) and interact a compound (ATAH) with potassium hydroxide and carbon disulfide to prepare a compound 3-acetyl-2-{4-[2-(5-mercapto-1,3,4-oxadiazol-2-yl)- 2-oxoethoxy] phenyl} thiazolidine-4-carboxylic acid (ATASO). All synthesis compounds were identified using Mass-EI, FT-IR, and (1H, 13C) NMR Spectra. Antibacterial activity of synthesis compounds was studied against two kinds of bacteria (E.coil and S.aureus) and studied as an antioxidant, as well the study of the compound with high efficacy in the direction of oxidation anticancer (MCF7) and determine an IC50.