The present invention provides sialic acid analogs and their compositions useful for the treatment of sialic acid deficiencies.

Disclosed are new compounds of formulae:

##STR00001##

Wherein: R.sup.1 and R.sup.2 can be independently H; a C.sub.1 to C.sub.6 alkyl including methyl, ethyl, propyl, butyl; aryl including phenyl, para-methoxyphenyl; or R.sup.1,R.sup.2 together with the carbon C-6 can be a cyclopentylidene or cyclohexylidene; each of these groups being substituted or not; and R.sup.3 can be a C.sub.1 to C.sub.6 alkyl including methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl; or aryl including phenyl, methylphenyl, ethylphenyl, each of these groups being substituted or not. The invention also relates to their method of manufacture and their use for the synthesis of Ara-N.sub.3, Kdo-N.sub.3 and 4eKdo-N.sub.3.

Disclosed are new compounds of formulae:

##STR00001##

Wherein: R.sup.1 and R.sup.2 can be independently H; a C.sub.1 to C.sub.6 alkyl including methyl, ethyl, propyl, butyl; aryl including phenyl, para-methoxyphenyl; or R.sup.1,R.sup.2 together with the carbon C-6 can be a cyclopentylidene or cyclohexylidene; each of these groups being substituted or not; and R.sup.3 can be a C.sub.1 to C.sub.6 alkyl including methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl; or aryl including phenyl, methylphenyl, ethylphenyl, each of these groups being substituted or not. The invention also relates to their method of manufacture and their use for the synthesis of Ara-N.sub.3, Kdo-N.sub.3 and 4eKdo-N.sub.3.

According to the present invention, a crystal of ammonium N-acetylneuraminate anhydrate, and a process for producing a crystal of ammonium N-acetylneuraminate anhydrate, comprising adding or adding dropwise a solvent selected from the group consisting of alcohols and ketones to an aqueous N-acetylneuraminic acid solution containing an ammonium-containing compound and having a pH of 3.0 to 9.0 to precipitate a crystal of ammonium N-acetylneuraminate anhydrate, and collecting the crystal of ammonium N-acetylneuraminate anhydrate from the aqueous solution, can be provided.

The present invention provides sialic acid analogs and their compositions useful for the treatment of sialic acid deficiencies.

The present invention provides sialic acid analogs and their compositions useful for the treatment of sialic acid deficiencies.

The invention relates to methods of producing, and compositions comprising, an isolated alpha (2.fwdarw.8) or (2.fwdarw.9) oligosialic acid derivative bearing a non-reducing end enriched for one or more de-N-acetyl residues and resistant to degradation by exoneuraminidase. A representative production method involves: (i) treating an alpha (2.fwdarw.8) or (2.fwdarw.9) oligosialic acid precursor having a reducing end and a non-reducing end with sodium borohydride under conditions for de-N-acetylating the non-reducing end; and (ii) isolating alpha (2.fwdarw.8) or (2.fwdarw.9) oligosialic acid derivative having one or more de-N-acetylated residues and a non-reducing end that is resistant to degradation by exoneuraminidase. Isolated alpha (2.fwdarw.8) or (2.fwdarw.9) oligosialic acid derivatives that comprise a non-reducing end de-N-acetyl residue are provided, as well as antibodies specific for the derivatives, compositions comprising the derivatives, kits, and methods of use including protection against and detection of E. coli K1 and N. meningitidis bacterial infection, and in diagnosing and treating cancer.