Carbohydrates Containing Nitrogen or Sulfur in the “Hemiacetal” Ring

Abstract

P: measured degree of polarization; PO: limiting degree of polarization for the frozen solution; T: lifetime of the excited state; 9 : viscosity of the solvent at the temperature T; V : (effective) molecular volume.In 5-amino-5-deoxy-and 5-thioaldoses, a 6-membered hemiace tal ring can be formed by incorporation of a nitrogen or sulfur atom into the ring instead of the oxygen present in pyranoses. In the case of 5-(N-acylamido)-5-deoxyaldoses, the nucleophilic strength of the amide grouping is lowered, with the result that ring closure occurs only when sterically favored, or when a side reaction with formation of furanose is not possible. On the other hand, 5-amino-5-deoxyaldoses containing a free amino group readily form 6-membered "hemiacetal" rings. The resulting piperidinoses possess properties that are unusual in sugars, since they contain the 2-hydroxypiperidine ring system. Piperidinoses are stable to alkalis and labile to acids; they rearrange in the presence of acids to give Amadori compounds, or lose three molecules of water to give derivatives of p-hydroxypyridines. Owing to the high reactivity of the mercapto group, 5-thioaldoses form only sugars with rings containing sulfur, the behavior of which resembles that of the oxygen analogues. 4-Amino-4-deoxy-and 4-thioaldoses can form 5-membered rings containing nitrogen and sulfur.

Minimal In Vivo Efficacy of Iminosugars in a Lethal Ebola Virus Guinea Pig Model

“…With this in mind, we sought to identify whether a licensed drug, Miglustat ( N -butyl deoxynojirimycin, N B-DNJ), could be of use in the treatment of EVD. N B-DNJ is an iminosugar, a class of sugar mimics in which a nitrogen atom is substituted for the endocyclic oxygen [2, 3]. As a result, many iminosugars are inhibitors of sugar utilising enzymes, such as glycosidases and glycosyltransferases [4, 5].…”

Isolation of 4‐amino‐4‐deoxy‐L‐arabinose from S and R form bacterial lipopolysaccharides

“…Although this is the first known report of the biological occurrence of a 4-amino ~entose, the chemical syntheses of 4-amino pentoses have been reported [5,6]. These reports indicate that the instability of the 4-amino-L-arabinose, (particularly in a neutral or alkaline environment) and its tendency to form a pyrrolidine ring, are in accord with results * 2-Amino-D-lyxo~e was used in our experiments; for simplicity, formula (3) shows the L-form.…”

Structure–Activity Studies of N‐Butyl‐1‐deoxynojirimycin (NB‐DNJ) Analogues: Discovery of Potent and Selective Aminocyclopentitol Inhibitors of GBA1 and GBA2

“…Found widespread in plants and microorganisms, iminosugars were first isolated and synthesized in the 1960s . They differ from monosaccharides in that the endocyclic oxygen atom is replaced by a basic nitrogen and that they lack the anomeric hydroxy group (Figure ).…”

“…Found widespread in plants and microorganisms, iminosugars were first isolated and synthesized in the1 960s. [1,2] They differ from monosaccharides in that the endocyclic oxygen atom is replaced by ab asic nitrogen and that they lack the anomeric hydroxy group (Figure 1). Iminosugars mimic carbohydrates or their hydrolysis transition state [3] [the intermediate glycosyl (oxycarbenium) cation or the protonated glycoside] and there-fore often inhibit carbohydrate-processinge nzymes such as glucosidases.…”