N,N-Diacetylsialyl chloride—a novel readily accessible sialyl donor in reactions with neutral and charged nucleophiles in the absence of a promoter

Phage capsid nanoparticles with defined ligand arrangement block influenza virus entry

“…pyridine, acetic anhydride, room temperature, 14 h, 2.) acetyl chloride, N,N-diisopropylethylamine, 0°C to room temperature, 2 h. Sialic acid chloride 11 was synthesized according a published protocol using peracetylated sialic acid 7 40 : Scheme S 2: Synthesis of sialic acid chloride 11. Conditions: a) anhydrous methanol, hydrochloric acid, acetyl chloride, 0°C, 12 h.…”

Simple and Rapid Procedures for the Synthesis of 5‐Acylated 4β‐Acylamido‐ and 4β‐Acetoxyneuraminic Acid Glycals

“…The presence of an oxazoline ring was also strongly supported by an evident shielding of the doublet attributed to the H‐6 proton (shifted to δ = 3.62 ppm) and by the value of the coupling constant of the H‐3 and H‐4 ( J = 4.1 Hz) that, in respect to the FANA 4α‐epimers 6a and 6f , shows the same significant variations observed in the 1 H NMR spectrum of the oxazoline 8 and those of the corresponding compounds 5a and 5b (see the Exp. Section) 31. Finally, the presence of the oxazoline ring was unambiguously established by its easy transformation upon treatment with aqueous trifluoroacetic acid into the corresponding 4β‐hydroxy FANA glycal 16 .…”

SnCl4-catalyzed solvent-free acetolysis of 2,7-anhydrosialic acid derivatives

“…Next, acetolysis of 2,7-anhydro derivative 6 was examined with SnCl 4 as catalyst under neat conditions, which provided the expected β-ring-opened product 12 in a moderate yield ( Table 1, It is known that anomeric acetates can be transformed smoothly into thioglycoside [15,16,35] and sialyl halide [38,39] donors when treated with a thiol in the presence of triflic acid, BF 3 ⋅OEt 2 , and HCl, respectively.…”