4-Methylphenyl 2-O-benzoyl-3-O-(9-fluorenylmethoxycarbonyl)-4-O-Benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside

4-Methylphenyl 2-O-benzoyl-3-O-(9-fluorenylmethoxycarbonyl)-4-O-Benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside

4-Methylphenyl 2-O-benzoyl-3-O-(9-fluorenylmethoxycarbonyl)-4-O-Benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside is a complex thioglycoside derivative utilized in carbohydrate chemistry, particularly in the synthesis of oligosaccharides and glycoconjugates. This compound features a β-D-galactopyranoside core with multiple protective groups that enhance its reactivity and facilitate selective transformations during glycosylation processes.

Structural Features

• Core Structure: The backbone consists of a β-D-galactopyranoside unit with a thio group at the anomeric position (C1), which enhances its reactivity as a glycosyl donor.
• Protective Groups:
  • Benzoyl group at O-2, providing acid-labile protection that can be selectively removed under acidic conditions.
  • Benzyl group at O-4, which is stable under basic conditions and allows for controlled reactions without interfering with other functional groups.
  • 9-Fluorenylmethoxycarbonyl (Fmoc) at O-3, which is base-labile and can be selectively removed to activate the hydroxyl for further reactions.
  • Levulinoyl group at O-6, offering acid-sensitive protection that can be removed to expose the hydroxyl for subsequent glycosylation.

Synthesis Strategy

The synthesis typically involves several key steps:

1. Benzoylation: The hydroxyl group at O-2 is protected by benzoylation using benzoyl chloride in the presence of a base.
2. Benzylation: The O-4 position is then benzylated using benzyl bromide and a suitable base.
3. Fmoc Protection: The hydroxyl group at O-3 is protected with Fmoc, which can be selectively removed later for further glycosylation reactions.
4. Levulinoylation: The O-6 position is modified with levulinic acid to introduce the levulinoyl group.

Physicochemical Properties

• Molecular Formula: Estimated as C₃₆H₄₀O₉S based on the substituent analysis.
• Appearance: Typically appears as a white crystalline solid, common for similar compounds in carbohydrate chemistry.
• Solubility: Soluble in polar aprotic solvents such as DMSO, DMF, and dichloromethane (DCM).
• Storage Conditions: Recommended to be stored at low temperatures (−20°C) under inert atmosphere to maintain stability.

Applications

• This compound serves as an important intermediate in synthesizing glycoconjugates and oligosaccharides due to its orthogonal protecting groups that allow for selective deprotection and further functionalization.
• It can also be utilized in studies related to glycan biology, facilitating the exploration of glycan interactions and functions in various biological systems.

Safety and Handling

• Generally considered non-hazardous but standard laboratory precautions should be observed when handling organic compounds.
• Use gloves and work in a well-ventilated area or fume hood to minimize exposure.

This compound exemplifies advanced strategies in carbohydrate synthesis, showcasing how protective group chemistry can be leveraged to achieve complex glycosidic structures efficiently.

Citations:

1. https://www.beilstein-journals.org/bjoc/articles/21/27
2. https://pmc.ncbi.nlm.nih.gov/articles/PMC6259426/
3. https://application.wiley-vch.de/books/sample/3527340106_c01.pdf
4. https://pubs.acs.org/doi/10.1021/ed074p1297
5. https://pmc.ncbi.nlm.nih.gov/articles/PMC8423405/
6. https://pubs.rsc.org/en/content/articlelanding/2017/ob/c6ob02278b
7. https://pubs.acs.org/doi/10.1021/ol401166x