Abstract
Herein, this article was focused on the synthesis and discussed the spectroscopic characterizations of four new scandium(III) sulfa-drug complexes. The nomenclature and symbols of these drugs were sulfadimidine (sulp-1) , sulfanilamide (sulp-2) , sulfamethoxazole (sulp-3) and sulfadiazine (sulp-4). The microanalytical and spectroscopic analyses which utilized in this study were micro-analyses, magnetic, FT-IR, UV-Vis techniques. The mid infrared spectra deduced that the four sulfa-drug chelates acts as a bidentate chelates with scandium(III) ion via two nitrogen atoms of -NH2-Ar and -NH-SO2 groups. Also, the FTIR spectra of Sc3+ complexes referred to the existed of new medium weak bands in the range of 500 similar to 400 cm(-1) due to stretching vibration bands of nu(M-N). The elemental analysis technique confirmed the 1 : 2 stoichiometry between Sc(3+ )ions and sulp ligand with molecular formula [Sc(sulp)(2)(Cl)(2)] center dot Cl. At room temperature, the results of magnetic measurements for the Sc (III) complexes indicated that all of the synthesized complexes have a diamagnetic character with octahedral configuration. The electronic spectra of the free sulfa-drug ligands shows band at 275 and 310 nm which are intraligand charge transfer band. The electronic sbsorption spectra of the Sc3+ complexes were recorded using HMSO solvent. The spectra of complexes display bands within 275-388 nm, which attributed to pi-pi* , n-pi* and charge-transfer M-L-CT electronic transitions, which strongly favors the octahedral geometry around Sc(III) metal ions. (HNMR)-H-1 spectra of complexes referred to the downfield proton shifts of the -NH2 and NHSO2 groups, which supported the place of coordination. The half maximal inhibitory concentration (IC50) of the Sc-III complexes was assessed against the human hepato cellular carcinoma (HepG-2) tumor cell line.