An Investigation on the Synthesis, Structure and Specific Properties of Zn(II) and Cu(II) Complexes with Tryptophan

In this work, [Zn(Tryp)(2)(H2O)(2)] and [Cu(Tryp)(2)H2O] complexes were synthesized by using Zn2+ and Cu2+ (from Zn(CH3COO)(2), Cu(CH3COO)(2)center dot H2O, respectively) as central metal ions with tryptophan (HTryp) as ligand. The compositions and structures of the synthesized [Zn(Tryp)(2)(H2O)(2)] and [Cu(Tryp)(2)H2O] complexes have been investigated by energy-dispersive X-ray spectroscopy (EDS), infrared (IR), nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), thermal analysis (TG, TGA/DTG), and electrical conductivity methods. The obtained results demonstrated that in the synthesized complexes, tryptophan is a bidentate ligand. The bonding between the tryptophan with central metal is with (O, Namino) donor sets. The coordination number of Zn2+ and Cu2+ in the complexes is 6 and 5, respectively. The stability of synthesized complexes was also confirmed via testing in simulated gastric fluid environments.