DIRECT DETECTION OF ANTIPYRINE METABOLITES IN RAT URINE BY 13 C LABELING AND NMR SPECTROSCOPY

This paper is available online at http://www.dmd.org ABSTRACT: Antipyrine is a useful probe to evaluate variation of in vivo activities of oxidative hepatic drug-metabolizing enzymes. Here we describe a new approach usin

STUDIES ON THE STEREOSELECTIVE INTERNAL ACYL MIGRATION OF KETOPROFEN GLUCURONIDES USING 13 C LABELING AND NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY

This paper is available online at http://www.dmd.or

Enzymatic synthesis of novel oligosaccharides from <i>N</i>-acetylsucrosamine and melibiose using <i>Aspergillus niger</i> α-galactosidase, and properties of the products

<p>Two kinds of oligosaccharides, <i>N</i>-acetylraffinosamine (RafNAc) and <i>N</i>-acetylplanteosamine (PlaNAc), were synthesized from <i>N</i>-acetylsucrosamine and melibiose using the transgalactosylation activity of <i>Aspergillus niger</i> α-galactosidase. RafNAc and PlaNAc are novel trisaccharides in which d-glucopyranose residues in raffinose (Raf) and planteose are replaced with <i>N</i>-acetyl-d-glucosamine. These trisaccharides were more stable in acidic solution than Raf. RafNAc was hydrolyzed more rapidly than Raf by α-galactosidase of green coffee bean. In contrast, RafNAc was not hydrolyzed by <i>Saccharomyces cerevisiae</i> invertase, although Raf was hydrolyzed well by this enzyme. These results indicate that the physicochemical properties and steric structure of RafNAc differ considerably from those of Raf.</p> <p>Two kinds of novel trisaccharides were synthesized from N-acetylsucrosamine and melibiose, using transgalactosylation action of <i>Aspergillus niger</i> α-galactosidase.</p