(Pseudo)amide-linked oligosaccharide mimetics: molecular recognition and supramolecular properties

• José L. Jiménez Blanco,
• Fernando Ortega-Caballero,
• Carmen Ortiz Mellet and
• José M. García Fernández

Beilstein J. Org. Chem. 2010, 6, No. 20, doi:10.3762/bjoc.6.20

• activities, probably due to the presence of a hydrophilic sugar substituent at the nitrogen atom of the nor-tropane ring [71][72]. Several groups have shown that disaccharide ureas and carbamates with different bridging positions as α/β-anomers are readily accessible by the coupling reaction of aminosugars

Benzyne arylation of oxathiane glycosyl donors

• Martin A. Fascione and
• W. Bruce Turnbull

Beilstein J. Org. Chem. 2010, 6, No. 19, doi:10.3762/bjoc.6.19

• occasion as a 96:4 (α:β) mixture of anomers (Scheme 4d). This slight drop in stereoselectivity is consistent with the increased reactivity of benzylated relative to acetylated thioglycoside donors [13][32], commonly attributed to greater stabilisation of the developing positive charge on an oxacarbenium

Recognition properties of receptors consisting of imidazole and indole recognition units towards carbohydrates

• Monika Mazik and
• André Hartmann

Beilstein J. Org. Chem. 2010, 6, No. 9, doi:10.3762/bjoc.6.9

• observed for 4 and 5 are quite different to those of the recently described phenanthroline/aminopyridine-based receptors 22 and 23 (see Figure 4) [27][29], which show a strong preference for α-glucoside and α-galactoside vs. the β-anomers. Thus, depending on the nature of the recognition units used as

• and 5 with these monosaccharides to be much more favorable than those with the α-anomers 7a and 9. The curve fitting of the titration data for 4 and β-glucoside 6a suggested the existence of 1:1 and 2:1 receptor–sugar complexes in CDCl3 solutions with a stronger association constant for 1:1 binding

Synthesis of phosphonate and phostone analogues of ribose-1-phosphates

• Pitak Nasomjai,
• David O'Hagan and
• Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2009, 5, No. 37, doi:10.3762/bjoc.5.37

• -phosphate is described. Preparations of both the α- and β-phosphonate anomers are reported for the ribose and 5-fluoro-5-deoxyribose series and a synthesis of the corresponding cyclic phostones of each α-ribose is also reported. These compounds have been prepared as tools to probe the details of

Methods for the synthesis of polyhydroxylated piperidines by diastereoselective dihydroxylation: Exploitation in the two-directional synthesis of aza-C-linked disaccharide derivatives

• Andrew Kennedy,
• Adam Nelson and
• Alexis Perry

Beilstein J. Org. Chem. 2005, 1, No. 2, doi:10.1186/1860-5397-1-2

• substitution under the reaction conditions. In each case, the required products (26 and 30) were obtained in moderate (30–37% i.e. 67–71% per step) yield over the three synthetic steps as 66:34 mixtures of anomers. Nevertheless, the yields were deemed acceptable because, over the three steps, significant

• highly (>95:<5) diastereoselective. Fortunately, the anomers of the bis-allylic alcohols 27, 29 and 33 were separable by careful column chromatography. The stereochemical outcome of the Luche reduction had been remarkable: although the reaction had been highly diastereoselective in both heterocyclic