A simple synthesis of N-perfluoroacylated and N-acylated glycals of neuraminic acid with a cyclic aminic substituent at the 4\u3b1 position as possible inhibitors of sialidases

A simple protocol for the synthesis of N-perfluoroacylated and N-acylated glycals of neuraminic acid, having a secondary cyclic amines (morpholine or piperidine) at the 4\u3b1 position, has been set-up, starting from peracetylated N-acetylneuraminic acid methyl ester that undergoes, sequencially to its direct N-transacylation followed by a C-4 amination, a \u3b2-elimination, and a selective hydrolysis of the ester functions, without affecting the sensitive perfluorinated amid