Monosaccharide composition and glycosidic linkages analysis by ultra high performance liquid chromatography-triple quadrupole tandem mass spectrometry-Case study of plant polysaccharides.

Monosaccharide composition and glycosidic linkages analysis are essential for the structural characterization and biological activity research of polysaccharides. To simplify the analysis steps and improve detection efficiency, this study developed monosaccharide compositions and glycosidic linkages detection methods based on UPLC-QqQ-MS/MS, and established a plant polysaccharide glycosidic linkages library. Furthermore, the detailed analysis process of monosaccharide compositions and glycosidic linkages was presented through a plant polysaccharide (Chinese bayberry wine polysaccharide, CPW) example.

Rh(II)-catalyzed reaction of alpha-diazocarbonyl compounds bearing beta-trichloroacetylamino substituent: C-H insertion versus 1,2-H shift.

The Rh(II)-carbene reaction is dramatically affected by the neighboring substituents. If the neighboring substituent is an OH group, a1,2-H shift is the exclusive pathway. If it is an OAc group, a 1,2-acetoxy migration is observed.