SYNTHESIS OF 4-ALKOXY-N-ACETYLNEURAMINIC ACID

摘要

This invention relates to an improved process for the synthesis of 4-alkoxy-N-acetylneuraminic acids. According to the process of the invention, Nacetylneuraminic acid is first alkylated at C-1 and C-2, and then the vicinal hydroxyl groups at C-8 and C-9 are protected through the formation of a ketal. The resulting protected alkyl ester alkyl ketoside is then alkylated at the C4 position whereby the hydrogen of the C-4 hydroxyl group is replaced with an alkyl group to form an alkoxy group. Deprotection is accomplished through the removal of the ketal group at C-8 and C-9 and removal of the alkyl groups at C1 and C-2, thereby producing the 4-alkoxy-N-acetylneuraminic acid.