ChemInform Abstract: A SIMPLE APPROACH TO THE SYNTHESIS OF A MEMBRANE TEICHOIC ACID FRAGMENT OF STAPHYLOCOCCUS AUREUS

Exploratory N‐Protecting Group Manipulation for the Total Synthesis of Zwitterionic Shigella sonnei Oligosaccharides

“…To our satisfaction, when changing the Staudinger conditions for a Zn/AcOH‐mediated azide reduction, the two‐step sequence gave the N ‐TCP intermediate 10 in an improved 83 % yield (Scheme 2). Allyl glycosides 10 and 11 were submitted to Ir‐cat mediated allyl to propen‐1‐yl isomerization [39] . Subsequent propenyl hydrolysis promoted by iodine in the presence of sodium bicarbonate [31] furnished hemiacetal 14 in an acceptable yield.…”

A Rational Approach to Heparin-Related Fragments − Synthesis of Differently Sulfated Tetrasaccharides as Potential Ligands for Fibroblast Growth Factors

“…Disaccharide 4 also afforded glycosyl donor 8 in 84% overall yield (Scheme 2) by a two-step deallylation [isomerization of the allyl group to the propenyl group with (1,5-cyclooctadiene)bis(methyldiphenylphosphane)iridium hexafluorophosphate catalyst [12] under hydrogen, followed by treatment with iodine in moist THF] and final conversion of the sugar hemiacetal into the corresponding trichloroacetimidate [13] (trichloroacetonitrile, cat. Disaccharide 4 also afforded glycosyl donor 8 in 84% overall yield (Scheme 2) by a two-step deallylation [isomerization of the allyl group to the propenyl group with (1,5-cyclooctadiene)bis(methyldiphenylphosphane)iridium hexafluorophosphate catalyst [12] under hydrogen, followed by treatment with iodine in moist THF] and final conversion of the sugar hemiacetal into the corresponding trichloroacetimidate [13] (trichloroacetonitrile, cat.…”