Preparation, characterization and biological activity study of some new thiazolidine derivatives

Abstract EN

Thiazolidine-4-carboxylic acid is a cyclic sulfur amino acid, analogous in its structure to proline, a condensation product of cysteine and formaldehyde.

Thiazolidine and N-acetyl derivative were reported to possess biological activity and both compounds that also tested for clinical use.

The study included synthesis of some thiazolidine derivatives [1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h] which were prepared from reaction of cysteine with benzaldehyde and its derivatives under private conditions.

This reaction produces a mixture of isomers , Cis- (2S, 4S) and Trans- ( 2R, 4S), which could not be Separated, An equilibrium resulting from epimerization at C(2) occurs between two isomers, The Cis/Trans ratios were strongly dependent on the nature of the solvent.

These compounds above react with acetic anhydride to prepare the compounds [2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h] and which represents reaction protection for an amine group, Then these latter compounds react with the amine (2-amino-6-ethoxy benzothiazole) to form compounds thiazolidine-4-carboxylic amide [3a, 3b, 3c, 3d, 3e, 3f, 3g, 3h] .

The new synthesized compounds were identified by melting points and FT-IR, 1HNMR, 13CNMR and mass spectrum.

The biological activities of some preparation compounds were studied against two types of bacteria one of them were gram negative (Klebsiella Pneumonia) and other were gram positive (Staphylococcus aueruse).