Sir: Rubradirin'-" contains a C8H,5NO5* moiety not found in rubradirin B5). We here report that acid hydrolysis of rubradirin afforded this fragment which was found to be a nitrosugar we have named L-rubranitrose. L-Rubranitrose is shown to have structure la. It is stereoisomeric with evernitrose, 26,1), found in the unrelated antibiotics, everninomicins B and C. Anomeric Ia, b was separated fr...

Extensins are plant-derived glycoproteins that are densely modified by oligo-arabinofuranosides linked to hydroxyproline residues. These glycoproteins have been implicated in many aspects of plant growth and development. Here, we describe the chemical synthesis of a tetrameric β(1-2)-linked arabinofuranoside that is capped by an α(1-3)-arabinofuranoside and a similar trisaccharide lacking the c...

While the properties of biochar are closely related to its functional groups, it is unclear under what conditions biochar develops its properties. In this study, two-dimensional (2D) (13)C nuclear magnetic resonance (NMR) correlation spectroscopy was for the first time applied to investigate the development of functional groups and establish their relationship with biochar properties. The resul...

A versatile route for the synthesis of N-linked glycoamino acids from readily available glycals is reported. A variety of glycals possessing different carbohydrate templates (mono-, di- and trisaccharide glycals) were shown to undergo a novel iodine catalyzed stereoselective diamination reaction with chloramine-T. Taking advantage of the difference in the reactivity between the anomeric and C2 ...

In the aldohexopyranose idose, the unique presence of three axial ring hydroxyl groups causes considerable conformational flexibility, rendering it challenging to study experimentally and an excellent model for rationalizing the relationship between puckering and anomeric configuration. Puckering in methyl α- and β-L-idopyranosides was predicted from kinetically rigorous 10 μs simulations using...

objectives juvenile myoclonic epilepsy(j.m.e.) needs life-long anti-epileptic drug (aed) treatment. of various drugs tried in this condition, valproate effectively treats all types of seizures seen in j.m.e. among valproate side effects, neural tube defects (ntd) in the offspring, is a deterring factor in its use in childbearing period. to avoid ntd, most authorities advise on switching to aed ...

The anomeric specificity of D-glucose metabolism in erythrocytes has been since 1985 the matter of extensive investigations reported in about ten publications. The present report aims at providing an integrated review of the major findings on this issue.

An unexpected stereoselective anomeric substitution with carbamates promoted by HNTf2 is described here. Our experiments suggest that the observed diastereoselectivity is a result of thermodynamic equilibration of protonated N-acyl aminals.

The elaboration of a 6,6-spiroacetal scaffold to incorporate a nucleoside unit at the anomeric position is described. The novel spiroacetal-nucleoside hybrids were generated via nucleosidation of acetoxy-spiroacetal with a series of silylated nucleobases under Vorbrüggen conditions.

In the title compound, C(13)H(16)Cl(3)NO(8), the trichloro-acetimidate group is located in an axial postion on the anomeric carbon of the sugar ring.