title: Further evidence for detection of short-lived transient hypomanganate(V) and manganate(VI) intermediates during oxidation of some sulfated polysaccharides by alkaline permanganate using conventional spectrophotometric techniques.
abstract: Spectrophotometric evidence for the formation of hypomanganate(V), [CAR-Mn(V)O43-], and manganate(VI), [CAR-Mn(VI)O42-], intermediate complexes has been confirmed during the oxidation of iota- and lambda-carrageenan-sulfated polysaccharides (CAR) by alkaline permanganate at pHs 12 using a conventional spectrophotometer. These short-lived intermediate complexes were identified and characterized. A reaction mechanism in good consistence with the experimental results is suggested.
authors.affiliation: Chemistry Department, Faculty of Applied Sciences, Umm Al-Qura University, Makkah Al-Mukarramah, Saudi Arabia.
authors.forename: Ishaq A
authors.initials: IA
authors.lastname: Zaafarany
authors.forename: Abd Alla S N
authors.initials: AA
authors.lastname: AlArifi
authors.forename: Ahmed
authors.initials: A
authors.lastname: Fawzy
authors.forename: Gamal A
authors.initials: GA
authors.lastname: Ahmed
authors.forename: Said A
authors.initials: SA
authors.lastname: Ibrahim
authors.forename: Refat M
authors.initials: RM
authors.lastname: Hassan
authors.forename: Hideo D
authors.initials: HD
authors.lastname: Takagi
mesh_terms: D000042:Absorption; D002351:Carrageenan / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D017895:Manganese Compounds / Q000032:analysis* / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000032:analysis* / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D013053:Spectrophotometry; D013464:Sulfuric Acids / Q000737:chemistry*
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D011134:Polysaccharides; D013464:Sulfuric Acids; C048856:permanganic acid; D002351:Carrageenan; C033158:sulfuric acid