Fmoc-protected disglycosylated serine building blocks—the engine for glycopeptide chemical synthesis 878483-09-1

At the forefront of glycoscience and glycodrug research and development, chemists continue to seek key tools that can simplify the construction of complex molecules and improve synthesis efficiency. Among them, a class of carefully designed and highly functional amino acid derivatives are playing an irreplaceable role. L-Serine,O-[4,6-di-O-acetyl-2-(acetylamino)-2-deoxy-3-O-[3,4,6-tri-O-acetyl-2-(acetylamino)-2-deoxy-β-D-glucopyranosyl ]-α-D-galactopyranosyl]-N-[(9H-fluoren-9-ylmethoxy)carbonyl]-is such an advanced intermediate for the synthesis of complex glycopeptides. It provides a strong chemical basis for exploring the biological functions of glycosylation and developing the next generation of biotherapeutics.

Chemical Information

Chemical name: L-Serine, O-[4,6-di-O-acetyl-2-(acetylamino)-2-deoxy-3-O-[3,4,6-tri-O-acetyl-2-(acetylamino)-2-deoxy-β-D-glucopyranosyl]-α-D-galactopyranosyl]-N-[(9H-fluoren-9-ylmethoxy)carbonyl]-

Common name: Fmoc-Ser(Ac₃GalNAcβ1-3Ac₃GlcNAcα)-OH (abbreviation based on sugar structure)

Chemical formula: C₄₄H₅₃N₃O₂₀

Molecular weight: 943.9 g/mol

CAS number: 878483-09-1

Category: Glycopeptides

Structural features

The design of this molecule contains the ingenious logic of synthetic chemistry, and its structural characteristics directly determine its excellent performance in solid-phase synthesis of glycopeptides:

Pre-assembled disaccharide module: The core of the molecule is a well-defined disaccharide unit (GalNAcβ1-3GlcNAc) connected to the oxygen atom of the serine side chain through an α-glycosidic bond. This preformed glycosylation structure with a specific stereoconfiguration (β1-3 linkage) eliminates the complex steps of glycosylation reaction directly on the peptide chain and avoids the problems of regioselectivity and stereoselectivity control.

Comprehensive protecting group strategy: All hydroxyl groups on the sugar ring (except the linking site) are protected by acetyl groups (Ac), and the amino groups are also acetylated. This comprehensive protection ensures that during the subsequent polypeptide chain elongation process, the sugar moiety remains inert to various chemical conditions used (such as acidic and alkaline environments) and no side reactions occur, thus ensuring the structural integrity of the final product.

Synthetic compatibility conferred by Fmoc protection: The α-amino group of serine is protected by 9-fluorenylmethoxycarbonyl (Fmoc). This is one of the most commonly used temporary protecting groups in solid-phase peptide synthesis. It can be efficiently and reversibly removed under mild alkaline conditions (such as piperidine). It is fully compatible with standard Fmoc solid-phase synthesis strategies, allowing this building block to be seamlessly embedded into the growing peptide chain sequence.

Main applications and advantages

Key intermediates in the synthesis of complex glycopeptides and glycoprotein mimetics

In glycobiology research, it is crucial to obtain glycopeptides with well-defined and uniform structures. The compound serves as a "ready-to-use" disglycosylated amino acid building block that can be directly used in automated solid-phase peptide synthesizers. Researchers can precisely introduce them into specific positions of the peptide chain just like assembling ordinary amino acids, thereby efficiently and reproducibly constructing glycopeptides containing specific O-linked glycoforms (here, the core structure derived from the Tn antigen). This greatly accelerates the preparation of glycopeptide probes for structure-function relationship studies, antibody production, or molecular interaction analysis.

A powerful tool for sugar vaccine and sugar drug discovery

Many important biological processes, such as cell recognition, immune response, and disease development, rely on glycosylation modifications. Vaccines based on specific tumor-associated carbohydrate antigens (such as Tn, sTn antigens) are a research hotspot in cancer immunotherapy. The disaccharide structure carried by this molecule is the core component of the relevant antigen. It can be used to quickly synthesize a series of structurally precise glycopeptide libraries carrying the sugar structure, which can be used to evaluate their immunogenicity, screen epitopes that can stimulate specific immune responses, and provide lead compounds for the design of new sugar vaccines or sugar-targeted drugs.

Standardized unit for studying the effects of glycosylation on peptide conformation and stability

Glycosylation can significantly change the physical and chemical properties and three-dimensional conformation of the parent peptide, thereby affecting its stability, receptor binding affinity and biological activity. By systematically introducing this structurally precise building block into different positions of the peptide chain, scientists can study the quantitative impact of glycosylation (especially specific disaccharide structures) on peptide backbone conformation, protease resistance, and biological function in a modular manner, providing fundamental data for the rational design of glycopeptide therapeutics with optimized properties.

Conclusion

L-Serine,O-[4,6-di-O-acetyl-2-(acetylamino)-2-deoxy-3-O-[3,4,6-tri-O-acetyl-2-(acetylamino)-2-deox y-β-D-glucopyranosyl]-α-D-galactopyranosyl]-N-[(9H-fluoren-9-ylmethoxy)carbonyl]- represents a sophisticated tool in glycopeptide synthetic chemistry. It transforms the challenging glycosylation problem into a tractable amino acid assembly problem, building an efficient and reliable chemical bridge across the gap from basic glycobiology research to the development of innovative glycodrugs. As glycoscience becomes increasingly important in the fields of life, health and disease treatment, the value of such well-designed synthetic building blocks will surely be further demonstrated.

The above information is provided by the editor of KASONS and is for scientific research only.