16932-62-0Relevant articles and documents
Sodium N-Chlorobenzenesulfonamide as a Selective Oxidant for Hexosamines in Alkaline Medium: A Kinetic and Mechanistic Study
Rangappa, Kanchugarakoppal S.,Raghavendra, Manikanahally P.,Mahadevappa, Dandinasivara S.,Channegowda, Doddegowda
, p. 531 - 536 (1998)
Oxidation of D-mannosamine (1), D-glucosamine (2), and D-galctosamine (3) by sodium N-chlorobenzenesulfonamide or chloramine-B (CAB) at 313 K is followed by a shortening of carbon chain and obeys the rate law, rate = k[CAB][sugar][HO-]x, where x is less than unity. The products are arabinonic acid, ribonic acid, and erythronic acid for 1 and 2 with smaller amounts of glyceric and hexonic acids, while lyxonic and threonic acids are predominant in the oxidation of 3 with smaller amounts of glyceric and hexonic acids. Proton inventory studies made in a H2)O-D2)O mixture point toward a single transition state. In the proposed mechanism the alkoxy anion (S-) of the hexosamine formed in a base-catalyzed reaction at C-1 carbon is subjected to an electrophilic rate-limiting attack by Cl+ of the oxidant. The hexonic acid formed is decarboxylated with loss of ammonia to form the respective pentose, which is further converted into the corresponding pentonic acid. The breaking of the bond between C-1 and C-2 carbons in pentose yields tetronic acids. The thermodynamic parameters for sugar alkoxy anion formation and activation parameters for the rate-limiting step have been evaluated.
Oxidative behaviour of some aminosugars towards chromic acid in perchloric acid medium in the absence and presence of micellar environment
Gupta, Kalyan Kali Sen,Tribedi, Partha Sarathi,Gupta, Shipra Sen,Sen, Pratik Kumar
, p. 546 - 550 (2007/10/02)
The oxidative behaviour of some aminosugars towards chromium(VI) in perchloric acid medium has been investigated.Chromium(VI) reacts with glucosamine and galactosamine by a similar mechanistic path through the intermediate formation of 1:1 complex between the reactants whereas the kinetic evidence for such 1:1 complex formation between protonated mannosamine and the reactive oxidant is insignificant.The influence of added micelle on the rate has also been studied.
