51547-37-6Relevant articles and documents
Preparation method of gluconic acid
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Paragraph 0009; 0021; 0024-0059, (2019/06/05)
The invention discloses a method for preparing gluconic acid from glucose as a raw material with a catalytic oxidation means. Gluconic acid is prepared through oxidation of glucose by an aqueous phasewith air or oxygen as an oxidizing agent and a transition metal compound and nitrous acid or nitrite as a composite catalyst. The reaction is simple in operation and mild in condition, the glucose conversion rate is high, the selectivity of the gluconic acid product is good, and the method has important application prospects.
Aqueous oxidation of sugars into sugar acids using hydrotalcite-supported gold nanoparticle catalyst under atmospheric molecular oxygen
Tomar, Ravi,Sharma, Jatin,Nishimura, Shun,Ebitani, Kohki
supporting information, p. 843 - 845 (2016/07/16)
Hydrotalcite-supported gold nanoparticles show good activity as a heterogeneous catalyst for the oxidation of monosaccharides (xylose, ribose, galactose and mannose) and disaccharides (lactose and cellobiose) into the corresponding sugar acids under external base-free conditions in water solvent using atmospheric pressure of molecular oxygen. The produced sugar acids were thoroughly identified by 1H-, 13C-, and HMQC-NMR and ESI-FT-ICR MS spectroscopic techniques.
Online Investigation of Aqueous-Phase Electrochemical Reactions by Desorption Electrospray Ionization Mass Spectrometry
Lu, Mei,Liu, Yong,Helmy, Roy,Martin, Gary E.,Dewald, Howard D.,Chen, Hao
, p. 1676 - 1685 (2015/09/22)
Electrochemistry (EC) combined with mass spectrometry (MS) is a powerful tool for elucidation of electrochemical reaction mechanisms. However, direct online analysis of electrochemical reaction in aqueous phase was rarely explored. This paper presents the online investigation of several electrochemical reactions with biological relevance in the aqueous phase, such as nitrosothiol reduction, carbohydrate oxidation, and carbamazepine oxidation using desorption electrospray ionization mass spectrometry (DESI-MS). It was found that electroreduction of nitrosothiols [e.g.; nitrosylated insulin B (13-23)] leads to free thiols by loss of NO, as confirmed by online MS analysis for the first time. The characteristic mass shift of 29 Da and the reduced intensity provide a quick way to identify nitrosylated species. Equally importantly, upon collision-induced dissociation (CID), the reduced peptide ion produces more fragment ions than its nitrosylated precursor ion (presumably the backbone fragmentation cannot compete with the facile NO loss for the precursor ion), thus facilitating peptide sequencing. In the case of saccharide oxidation, it was found that glucose undergoes electro-oxidation to produce gluconic acid at alkaline pH, but not at neutral and acidic pHs. Such a pH-dependent electrochemical behavior was also observed for disaccharides such as maltose and cellobiose. Upon electrochemical oxidation, carbamazepine was found to undergo ring contraction and amide bond cleavage, which parallels the oxidative metabolism observed for this drug in leucocytes. The mechanistic information of these redox reactions revealed by EC/DESI-MS would be of value in nitroso-proteome research and carbohydrate/drug metabolic studies.
