title: Synthesis and antioxidant activities of transition metal complexes based 3-hydroxysalicylaldehyde-S-methylthiosemicarbazone.
abstract: The nickel(II), iron(III), oxovanadium(IV) complexes of the 3-hydroxysalicylidene-S-methyl-thiosemicarbazone (L) were obtained from the 3-hydroxysalicyldehyde-S-methylthiosemicarbazone with the R1-substituted-salicylaldehyde (R1: H, 3-OH) in the presence of Ni(II), Fe(III), VO(IV) as template ion. The ligand and its complexes were characterized by elemental analysis, electronic, UV/Vis., (1)HNMR, EPR and IR studies. The free ligand and its metal complexes have been tested for in vitro antioxidant capacity by reduction of copper(II) neocuproine (Cu(II)-Nc) using the CUPRAC method. The ligand exhibited more potent in vitro antioxidant capacity than its complexes. The obtained trolox equivalent antioxidant capacity (TEAC) value of the iron(III) complex (TEACCUPRAC=3.27) was higher than those of other complexes. Furthermore, the antioxidant activity of the free ligand and its complexes were determined by in vitro methods measuring the scavenging activity of reactive oxygen species (ROS) including hydroxyl radical (OH), superoxide anion radical (O2(-)), and hydrogen peroxide (H2O2), showing that especially the V(IV) and Fe(III) complexes had significant scavenging activity for ROS.
authors.affiliation: Department of Chemistry, Inorganic Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey. Electronic address: tulaybal@istanbul.edu.tr.
authors.forename: Tülay
authors.initials: T
authors.lastname: Bal-Demirci
authors.affiliation: Department of Chemistry, Inorganic Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey.
authors.forename: Musa
authors.initials: M
authors.lastname: Şahin
authors.affiliation: Department of Chemistry, Analytical Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey.
authors.forename: Esin
authors.initials: E
authors.lastname: Kondakçı
authors.affiliation: Department of Chemistry, Analytical Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Özyürek
authors.affiliation: Department of Chemistry, Inorganic Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey.
authors.forename: Bahri
authors.initials: B
authors.lastname: Ülküseven
authors.affiliation: Department of Chemistry, Analytical Chemistry Section, Istanbul University, 34320 Avcilar, Istanbul, Turkey.
authors.forename: Reşat
authors.initials: R
authors.lastname: Apak
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D005290:Ferric Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D013481:Superoxides; D013882:Thiosemicarbazones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D028561:Transition Elements / Q000138:chemical synthesis*; D014638:Vanadates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D056831:Coordination Complexes; D005290:Ferric Compounds; D016166:Free Radical Scavengers; D013882:Thiosemicarbazones; D028561:Transition Elements; D013481:Superoxides; D017665:Hydroxyl Radical; D014638:Vanadates; D006861:Hydrogen Peroxide
keywords: Antioxidant; Iron; Nickel; Thiosemicarbazone; Vanadium