The synthesis and characterization of novel N-ferrocenyl benzoyl amino acid and dipeptide derivatives

摘要

A series of novel A^ferrocenytybenzoyl ammo acid and dipeptide derivatives have been synthesized and characterized. It is intended that the incorporation of organometallic fragments onto amino acids and dipeptide moieties will lead to the development of new materials with innovative applications. In this project, a ferrocenyl benzoyl moiety has been attached to amino acid or dipeptide fragments using standard peptide chemistry. Though there are more than one potential uses for these new ammo acid derivatives, the presence of both hydrogen bond donating amide and redox active moieties would suggest that they should be cheap and effective lonophonc compounds and this may be their most financially exploitable application. In addition, investigations are ongoing to ascertain the biological activity of these compounds.ududThe synthesis of the //“(ferrocenyl)benzoyl ammo acid and dipeptide derivatives was achieved by couplmg the free N-termmus of an ammo acid ester (glycme, L-alanme, Lleucine, L-phenylalanme, p-alanine, 4-aminobutyric acid, ± 2-ammobutync acid, isobutync acid) or dipeptide esters (glycine-glycine, glycine-L-alanme, glycme-L-leucine, glycine-Lphenylalamne, L-alanme-glycme, L-alanine-L-alamne, L-alanine-L-leucine, L-alanme-Lphenylalanme, P-alanine-P-alamne) to the carboxyl group of the ortho, meta or para ferrocenyl benzoic acid by using the standard 1,3-dicyclohexylcarbodnmide (DCC), 1- hydroxybenzotnazole (HOBt) protocol.ududThese compounds were fully characterized by a range of spectroscopic techniques including, IR, UV-Vis, ‘H, 13C, DEPT 135 and HMQC NMR in addition to FAB-MS, ESI, MALDITOF and tandem MS X-ray crystal structures were also obtained m some cases. Cyclic voltammetric and NMR titration experiments were carried out in order to determine the anion sensing and/or recognition abilities of the N-(ferrocenyl)benzoyl glycme, P-alanme, glycine-glycme and p-alanine-p-alanine compounds. In the ]H NMR spectra, downfield shifts of the amide proton in order of 1 ppm were noted upon addition of H2P042" to a solution of N-(ferrocenyl)benzoyl-P-alanine-p-alanine ethyl ester. This is an indication that jV-(ferrocenyl)benzoyl amino acids and dipeptide derivatives may be applicable as effective anion sensmg compounds.