150718-07-3

Upstream product

• 489-46-3 sialic acid 
• 6813-81-6 N-acetyl neuraminic acid 
• 6931-68-6 methyl (5-acetamido-2,4,7,8,9-penta-O-acetyl-3,5-dideoxy-D-glycero-α-D-galacto-2-nonulopyranosid)onate 
• 67670-69-3 N-acetyl-4,7,8,9-tetra-O-acetyl-2-chloro-2-deoxyneuraminic acid methyl ester 
• 73208-80-7 methyl [methyl 4,7,8,9-tetra-O-acetyl-5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-non-2-ulopyranoside]onate 
• 72-87-7 N-acetyl-D-mannosamine 
• 67-56-1 methanol 
• 24967-27-9 2,3-dehydro-2-deoxy-N-acetylneuraminic acid 
• 18409-13-7 3'-sialyllactose 
• 6730-26-3 methyl (methyl 5-acetamido-3,5-dideoxy-D-glycero-α-D-galacto-2-nonulopyranosid)onate 

Relevant academic research and scientific papers

(13)C-N.M.R.-SPECTRAL STUDY OF THE MODE OF BINDING OF Mn2+ AND Gd3+ TO N-ACETYL-α-NEURAMINIC ACID

Natural-abundance, (13)C-n.m.r. spectroscopy was used to study the binding of Gd3+ and Mn2+ to N-acetyl-2-O-methyl-α-neuraminic acid (2) and to methyl N-acetyl-2-O-methyl-α-neuraminate (3).The results showed that Gd3+ , and Mn2+ bind in the region of the glycerol-1-yl side-chain and the 5-acetamido group of compound 3.When the α-NeuAc derivative contains a carboxylate anion, as in compound 2, multiple, metal-ion-binding sites occur, involving the head (the carboxyl end) and the tail (the glycerol-1-yl and 5-acetamido groups) of the molecule.

Molecular recognition of sialic acid end groups by phenylboronates

A multinuclear NMR study of the interaction between phenylboronic acid (PBA) and sialic acid (Neu5 Ac) has been performed. The latter compound is known to be over-expressed on the cell surface of tumor cells. The results of this investigation suggest that the binding of PBA to sialic acid is pH dependent. 17O NMR experiments with glycolic acid as the model compound prove that an interaction at the α-hydroxycarboxylate occurs at pH 9, while a study with threonic and erythronic acids shows that the PBA group interacts selectively with the vicinal diol functions at higher pH. Similarly, Neu5 Ac binds PBA through its α-hydroxycarboxylate at low pH ( 9) and through its glycerol side chain at higher pH values. The conditional stability constant of the phenylboronate ester at pH 7.4 is 11.4. On cell surfaces, sialic acid is connected to the neighboring sugar unit through the 2-hydroxy group. To mimic this the 2-α-O-methyl derivative of Neu5 Ac was included in this study. The erythro configuration of the hydroxy substituants prevents stable-complex formation at positions C7 and C8 and, consequently, the strongest interaction is observed at positions C8 and C9, leading to a five-membered 2-boron-1,3-dioxalate. In addition, a relatively small amount of the C7-C9 six-membered complex was observed. Molecular modeling studies confirm that the C8-C9 boronate complex has the lowest energy.

Differential recognition of diet-derived Neu5Gc-Neoantigens on glycan microarrays by carbohydrate-specific pooled human IgG and IgA antibodies

Sialic acids (Sias) cover vertebrate cell surface glycans. N-Acetylneuraminic acid (Neu5Ac) and its hydroxylated form N-glycolylneuraminic acid (Neu5Gc) are common Sia in mammals. Humans cannot synthesize Neu5Gc but accumulate it on cells through red-meat rich diets, generating numerous immunogenic Neu5Gc-neoantigens. Consequently, humans have diverse anti-Neu5Gc antibodies affecting xenotransplantation, cancer, atherosclerosis, and infertility. Anti-Neu5Gc antibodies circulate as IgG, IgM, and IgA isotypes; however, repertoires of the different isotypes in a large population have not been studied yet. Here, we used glycan microarrays to investigate anti-Neu5Gc IgGs and IgAs in intravenous immunoglobulin (IVIG) or pooled human IgA, respectively. Binding patterns on microarrays fabricated with Neu5Gc- and Neu5Ac-glycans, together with inhibition assays, revealed that different IVIG preparations have highly specific anti-Neu5Gc IgG reactivity with closely related repertoires, while IgAs show cross-reactivity against several Neu5Ac-glycans. Such different anti-Neu5Gc IgG/IgA repertoires in individuals could possibly mediate distinctive effects on human diseases.

SIALIDASE INHIBITORS AND PREPARATION THEREOF

New 2-deoxy-2,3-dehydro-sialic acids and 2,7-anhydro-sialic acids, which are useful as sialidase inhibitors, and enzymatic methods for preparing them are disclosed. The methods include forming a reaction mixture comprising a glycoside acceptor, a sialic acid donor, and a sialyltransferase; maintaining the reaction mixture under conditions sufficient to form a sialoside; and contacting the sialoside with a Streptococcus pneumoniae sialidase to form the sialic acid product. Methods for the inhibition and sialidases and the treatment of cancer and infectious diseases are also disclosed.

Synthesis of potential inhibitors of hemagglutination by influenza virus: Chemoenzymic preparation of N-5 analogs of N-acetylneuraminic acid

A chemoenzymic route to neuraminic acid 2 is described. This method is based on conversion of N-carbobenzoxymannosamine (ManCBz) 3 to N-carbobenzoxyneuraminic acid (Neu5CBz) 4, catalyzed by Neu5Ac aldolase. The Neu5CBz 4 was converted to the α-methyl glyc