title: Synthesis, pulse radiolysis, and in vitro radioprotection studies of melatoninolipoamide, a novel conjugate of melatonin and alpha-lipoic acid.
abstract: A novel conjugate of melatonin 2 and alpha-lipoic acid 4 has been prepared using DCC mediated coupling. The conjugate named melatoninolipoamide has been assigned its structure 1 on the basis of spectral analysis (UV, IR, NMR, and EI-MS). Pulse radiolysis studies of the conjugate were carried out in aqueous solutions with both oxidizing and reducing radicals. The results indicate that the melatonin moiety of the conjugate reacts preferably with oxidizing radicals and the lipoic acid moiety exhibits preferential reaction with reducing radicals. The in vitro radioprotection ability of 1 was examined by gamma-radiation induced lipid peroxidation in liposomes and hemolysis of erythrocytes, and compared the results with those of melatonin and alpha-lipoic acid. The studies suggest that the conjugate can be explored as a probable radioprotector.
authors.affiliation: Bio-Organic Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. achat@apsara.barc.ernet.in
authors.forename: S R
authors.initials: SR
authors.lastname: Venkatachalam
authors.forename: A
authors.initials: A
authors.lastname: Salaskar
authors.forename: A
authors.initials: A
authors.lastname: Chattopadhyay
authors.forename: A
authors.initials: A
authors.lastname: Barik
authors.forename: B
authors.initials: B
authors.lastname: Mishra
authors.forename: R
authors.initials: R
authors.lastname: Gangabhagirathi
authors.forename: K I
authors.initials: KI
authors.lastname: Priyadarsini
mesh_terms: D005609:Free Radicals / Q000737:chemistry; D008550:Melatonin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011675:Pulse Radiolysis / Q000379:methods; D011837:Radiation-Protective Agents / Q000138:chemical synthesis* / Q000737:chemistry; D008063:Thioctic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D005609:Free Radicals; D011837:Radiation-Protective Agents; C514599:melatoninolipoamide; D008063:Thioctic Acid; D008550:Melatonin