General base-catalyzed hyrdrolysis and carbonyl-18O exchange of N-(4-nitrobenzoyl)pyrrole
Article Abstract:
Hydrolysis kinetics for N-(4-nitrobenzoyl)pyrrole when base-promoted can be measured as they relate to buffer concentration at 25 degrees Celsius at several pH values. Carbonyl-18O exchange kinetics have been determined at a single pH value as a function of 1,4-diazobicyclo(2.2.2.)octane (DABCO) concentration. When the buffer concentration is zero, the measured ratio of 18O exchange to hydrolysis is about 0.04. As the DABCO concentration goes up, that value goes up and finally levels off at about 0.23. The buffer appears to function as a general base in catalysis of the water attack to generate an anionic tetrahedral intermediate and also to catalyze the breakdown of the intermediate to deliver hydrolysis products.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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N-Glycosyl phosphonamidates: potential transition-state analogue inhibitors of glycopeptidases
Article Abstract:
Synthesis of N-glycosyl phosphonamidates was carried out using coupling of peracetylated glycosylamines with a suitable phosphonochloridate and pyridine. Glycosyl phosphonamidate esters that are produced are dealkylated with bromotrimethylsilane followed by deacetylation. The target compounds have potential to be transition-state analogue inhibitors of glycopeptidases and may be haptens that can be used for producing catalytic antibodies that have glycopeptidase properties.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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Synthesis and evaluation of a bicyclic deoxymannojirimycin derivative as a potential glycosidase inhibitor
Article Abstract:
The aza-sugar 2,6-anhydro-1-deoxymannojirimycin, synthesized from 1,5-anhydro-D-glucitol, weakly inhibits a number of glycosidases. Such inhibitors may have therapeutic value in metabolic disorders, treatment of cancer metastasis, and viral infections.
Publication Name: Canadian Journal of Chemistry
Subject: Chemistry
ISSN: 0008-4042
Year: 1998
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