Search results for "saccharide"

Saccharide modified silica particles by enzymatic grafting

1997

The surface of silica particles has been chemically modified with oligo- or poly-(α,1→4)-D-glucopyranose (amylose) chains of various length by covalently attaching maltoheptaose derivatives to the solid support and enzymatic polymerization of glucose-1-phosphate with a potato phosphorylase as catalyst. The characterization of the products by solid-state NMR spectroscopy showed an interesting dependence of the linewidth with the grafting density of the glucan chains. The modified silica particles showed chiral discrimination in liquid chromatography.

Dextran-Based Polycations: Thermodynamic Interaction with Water as Compared With Unsubstituted Dextran, 2 - Flory/Huggins Interaction Parameter

2011

Increased Stability of Polysaccharide/Silica Hybrid Sub‐Millicarriers for Retarded Release of Hydrophilic Substances

2021

Membrane oligo- and polysialic acids

2011

AbstractPolysialic acid (polySia) and oligosialic acid (oligoSia) chains are linear polysaccharides composed of sialic acid monomers. The majority of biological poly/oligoSia chains are bound to membranes. There is a large diversity of membrane poly/oligoSia in terms of chain length, occurrence, biological function, and the mode of membrane attachment. Poly/oligoSia can be anchored to a membrane via a phospholipid (polySia in bacteria), a glycosphingolipid (oligoSia in gangliosides), an integral membrane glycoprotein, or a glycoprotein attached to a membrane via glycosylphosphatidylinositol. In eukaryotic cells, the attachment of a poly/oligoSia chain to the membrane anchor is usually throu…

New macrolactones from the defensive salivary secretion of soldiers of the african termite Pseudacanthotermes spiniger

1999

The salivary defensive secretion of large soldier termites of the species Pseudacanthotermes spiniger contains two novel macrocyclic lactones [22-keto-hexacosanolide (2) and 2-hydroxy-24-keto-octacosanolide (3)] together with the already known macrolactone hexacosanolide (1). In addition, the secretion contains important amounts of a polysaccharide based mainly upon β-glucopyranose, β-glucosamine and N-acetyl-β-glucosamine in equal amount.

ChemInform Abstract: New Macrolactones from the Defensive Salivary Secretion of Soldiers of the African Termite Pseudacanthotermes spiniger.

2010

The salivary defensive secretion of large soldier termites of the species Pseudacanthotermes spiniger contains two novel macrocyclic lactones [22-keto-hexacosanolide (2) and 2-hydroxy-24-keto-octacosanolide (3)] together with the already known macrolactone hexacosanolide (1). In addition, the secretion contains important amounts of a polysaccharide based mainly upon β-glucopyranose, β-glucosamine and N-acetyl-β-glucosamine in equal amount.

Behavior of carbohydrate-based material in black liquor during heating

2004

One industrial softwood Kraft black liquor was heat-treated (at 175 ?C and 190 ?C for 15-60 min) together with laboratory-made soda-AQ (wheat straw and reed canary grass) and Kraft (reed canary grass) black liquors (at 190 ?C for 30 min). The feedstock black liquors were characterized with respect to their polysaccharide (mainly xylem) and aliphatic carboxylic acid contents before and after the heat treatments. It was noted that, due to the higher amount of polysaccharides in the non-wood black liquors (8.2-16.6% of d.s) compared to that in the softwood black liquor (1.4% of d.s), the heat treatment in the former case resulted in a 5-30% increase in the amount of aliphatic acids formed by v…

d-Glucose as a multivalent chiral scaffold for combinatorial chemistry

2002

Due to their high density of functional groups and their availability in a variety of diastereomeric forms, monosaccharides are considered attractive scaffolds for combinatorial chemistry that allow the attachment and defined spatial alignment of up to five different pharmacophoric groups. For their application in combinatorial syntheses on solid phase, a set of selectively removable hydroxy protecting groups in combination with a cleavable anchor is required. Herein, we report on the construction and use of a versatile multivalent glucose building block for parallel synthesis on the solid phase.

On the Importance of Carbohydrate-Aromatic Interactions for the Molecular Recognition of Oligosaccharides by Proteins: NMR Studies of the Structure a…

2005

The specific interaction of a variety of modified hevein domains to chitooligosaccharides has been studied by NMR spectroscopy in order to assess the importance of aromatic-carbohydrate interactions for the molecular recognition of neutral sugars. These mutant AcAMP2-like peptides, which have 4-fluoro-phenylalanine, tryptophan, or 2-naphthylalanine at the key interacting positions, have been prepared by solid-phase synthesis. Their three-dimensional structures, when bound to the chitin-derived trisaccharide, have been deduced by NMR spectroscopy. By using DYANA and restrained molecular dynamics simulations with the AMBER 5.0 force field, the three-dimensional structures of the protein-sugar…

ChemInform Abstract: Glycoside Synthesis via Electrophile-Induced Activation of N-Allyl Carbamates.

2010

Abstract O-Benzyl-, O-acyl-, N-acyl- and isopropylidene-protected glycosyl N-allylcarbamates, obtained from anomerically unprotected monosaccharides and allyl isocyanate, are activated by an electrophile-induced cyclisation and react with hydroxyl compounds to form the corresponding glycosides.