SYNTHESIS AND SPECTROSCOPIC INVESTIGATIONS OF β-L-ASPARTYL-CYCLOHEXYLAMIDE AS POTENT LIGAND FOR TRANSITION METAL COMPLEXES

Igballe ABDIJI, Carmen SACALIS, Agim SHABANI, Ahmed JASHARI

Abstract

L-aspartic acid is a natural amino acid and a building block for peptides and proteins. Besides, a series of compounds and metallic complexes such as metalloproteins which contain acid residues have biological applications. In this course, a new route of preparation of β-L-aspartyl-cyclohexylamide was carried out by regioselective acylation of cyclohexylamine using N-phthaloyl-L-aspartic anhydride, followed by hydrolysis of phthaloyl group with hydrazine hydrate. The preparation of β-L-aspartylamide was attempted by an original method which involved 4 steps of synthesis. In the first synthetic step, N-carbethoxyphthalimide was used through a method developed in our group, managing to improve the conditions of reaction to not affect the chiral center. The second activation phase was performed in good yields, obtaining the pure product. In the third stage, the amine regioselectively attacked the β position and in the last step, the amide deprotection was achieved by hydrazinolysis. The structure of the intermediates and the final amide product was confirmed by HRMS, 1H- and 13C-NMR.

Pages: 72 - 81