Two procedures for the syntheses of labeled sialic acids and their 1,7-lactones

Synthetic phenylethanoid glycoside derivatives as potent neuroprotective agents

“…The target compound 7 was successfully prepared from intermediate 15 by the sequential removal of allyl and acetyl groups. Moreover, the target molecule 8 was prepared by the coupling reaction of compound 11 with the sialic acid derivative 21 [29] in the presence of benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBOP) and N-methylmorpholine (NMM). All compounds were characterized by their 1 H NMR, 13 C NMR, and HRMS analyses.…”

Facile Diastereoselective Entry to 4β‐Acylamidation of Neu5Ac2en Glycals Using Their N‐Perfluoroacylated Congeners as Key Tools

“…Indeed, some 2-unsaturated congeners (glycals) of Neu5Ac have shown important inhibitory activity against various bacterial and viral sialidases (neuraminidases, NA), enzymes involved in the spreading of influenza infection. [11] Continuing our interest in the chemistry of Neu5Ac and NA inhibitors, [12][13][14][15][16][17][18] we herein report a simple procedure to access 4β-acylaminoglycals sharing the structure of compounds 3a and 3b, chosen as models in the synthetic protocol. [11] Continuing our interest in the chemistry of Neu5Ac and NA inhibitors, [12][13][14][15][16][17][18] we herein report a simple procedure to access 4β-acylaminoglycals sharing the structure of compounds 3a and 3b, chosen as models in the synthetic protocol.…”

“…

An efficient protocol for the 4β-acylamidation of the N-acylated glycals of Neu5Ac by using the corresponding N-perfluoroacylated congeners as key tools has been developed 2508 and applied to the synthesis of glycals combining the features of the molecules with antiviral properties.Continuing our interest in the chemistry of Neu5Ac and NA inhibitors, [12][13][14][15][16][17][18] we herein report a simple procedure to access 4β-acylaminoglycals sharing the structure of compounds 3a and 3b, chosen as models in the synthetic protocol. This appeared an attractive goal, as only a few methods involving the use of phosphane or palladium/phosphane catalysts allow these derivatives to be synthesized.

…”

“…Continuing our interest in the chemistry of Neu5Ac and NA inhibitors, [12][13][14][15][16][17][18] we herein report a simple procedure to access 4β-acylaminoglycals sharing the structure of compounds 3a and 3b, chosen as models in the synthetic protocol. This appeared an attractive goal, as only a few methods involving the use of phosphane or palladium/phosphane catalysts allow these derivatives to be synthesized.…”

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

“…Methyl 5‐(Acetoxyacetamido)‐4,7,8,9‐tetra‐ O ‐acetyl‐3,5‐dideoxy‐2‐ O ‐methyl‐ D ‐ glycero ‐ D ‐ galcto ‐non‐2‐enonate (3e): Acetic anhydride (1.0 mL) was added dropwise to a stirred solution of 2‐ O ‐methyl‐5‐ N ‐glycolyl methyl β‐neuraminate23 (375 mg, 1.06 mmol) in anhydrous pyridine (2.0 mL) containing 4‐(dimethylamino)pyridine (ca. 1 mg) at 23 °C.…”