- A metal-free route towards 1,5-disubstituted 1,2,3-triazolylmethylene linked disaccharides: Synthesis in a biodegradable hydroxyl-ammonium-based aqueous ionic liquid media
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Suitably protected carbohydrates were joined together using 1,5-disubstituted 1,2,3-triazolylmethylene (1,5-DTM) linkers. The DTM linker was built by the 1,3-dipolar cycloaddition reactions of a series of sugar azides with vinyl sulfonylmethylene-modified furanose or pyranose under metal free conditions. Three different biodegradable hydroxylammonium based ionic liquids were studied in water as the reaction media. The N,N-dimethyl ethanolammonium formate-water mixture was found to be the best reaction medium because the reaction time was shortened considerably to generate a dozen new 1,5-DTM-linked disaccharides.
- Kayet, Anirban,Pathak, Tanmaya
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- Oligosaccharides derived from ribose-ribitol-phosphate, and vaccines containing them
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The present invention relates to the field of the Medicine, in particular with the chemical synthesis of oligosaccharide mixtures derived of ribose-ribitol-phosphate, which are used as active principle in vaccines for the prevention of infections caused byHaemophilus influenzaetype b (Hib), as well as with the vaccines containing said oligosaccharide mixtures. The oligasaccharide mixtures obtained by chemical synthesis of the present invention, comprise repeating units of formulae (phosphate-ribosa-ribitol)n or (ribose-ribitol-phosphate)n of at least 5 compounds of structure A or B, which represent the repeating unit of the capsular polysaccharide ofHaemophilus influenzaetype b and differ only by n, being n a value contained between 4 and 25 (n≧4 y≦25), and wherein R1or R2is a spacer for conjugation to a carrier, with the condition of R1=spacer if R2=H, or R2=spacer if R1=H. The invention also is related with the immunogens containing such oligosaccharide mixtures, with the vaccines containing said immunogens and with the methods to prepare these oligosaccharides as mixtures. Furthermore, the invention includes the use of the vaccines, alone or combined with other vaccines, for the prevention of the infections caused byHaemophilus influenzaetype b.
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Page column 19
(2010/02/07)
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- The synthesis of two repeating units of Haemophilus influenzae type a capsular antigen.
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The repeating units 2-O-beta-D-glucopyranosyl-L-ribitol 4'- and 1-phosphate of Haemophilus influenzae type a capsular antigen have been synthesised by condensation of an alpha-D-glucopyranosyl bromide derivative with 5-O-allyl-1,2,3-tri-O-benzyl-D-ribitol followed by selective deprotection of HO-4' or HO-1, phosphorylation, and removal of the blocking groups.
- Grzeszczyk,Banaszek,Zamojski
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p. 215 - 226
(2007/10/02)
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