Efficient method for the preparation of peracetylated Neu5Ac2en by flash vacuum pyrolysis.

ABSTRACT

Peracetylated Neu5Ac2en methyl ester, an intermediate in the synthesis of the influenza neuraminidase inhibitor Relenza, has been synthesized in high yields from peracetylated Neu5Ac methyl ester by flash vacuum pyrolysis. Mechanistic evidence including deuterium labeled studies and DFT (B3LYP) calculations suggest this transformation proceeds via an intramolecular syn-elimination.