Ethyl 3,4-di-O-benzoyl-2-O-benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside

Ethyl 3,4-di-O-benzoyl-2-O-benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside Ethyl 3,4-di-O-benzoyl-2-O-benzyl-6-O-levulinoyl-1-thio-β-D-galactopyranoside is a synthetic thioglycoside designed for controlled reactivity in carbohydrate synthesis. Its structure combines orthogonal protecting groups to enable sequential deprotection during oligosaccharide assembly. Structural Features Core : β-D-galactopyranoside backbone with an ethyl thio-group at the anomeric position (C1). Protection pattern : Benzyl ether at O-2 (base-stable). Benzoyl esters at O-3 and O-4 (acid-labile). Levulinoyl ester at O-6 (acid-sensitive, selectively removable). Synthesis Strategy Based on analogous methods in the search results: Selective benzylation at O-2 using benzyl bromide and a tin-based catalyst (e.g., di- n -butyltin oxide). Benzoylation at O-3 and O-4 with benzoyl chloride under mild basic conditions. Levulinoylation at O-6 via levulinic acid activation. Final purification by column chromatography (hexanes:EtOAc gradients). Physicochemical Properties Molecular formula : Estimated as C₃₄H₃₆O₉S (derived from substituent analysis). Appearance : White crystalline solid (common for similar thioglycosides). Solubility : Compatible with DCM , DMF , and chloroform . Storage : Stable at −20°C under inert atmosphere. Applications Glycosylation intermediate : The levulinoyl group allows selective deprotection (e.g., using hydrazine acetate ) to activate O-6 for further glycosylation. Orthogonal reactivity : Benzoyl (base-stable) and benzyl (acid-stable) groups enable sequential modifications in glycan synthesis. Key Advantages Regioselective control : Strategic protection simplifies access to branched oligosaccharides. Compatibility : Stable under glycosylation conditions (e.g., N -iodosuccinimide/triflic acid). This compound exemplifies advanced strategies in carbohydrate chemistry, balancing protective group orthogonality for precision in glycoconjugate synthesis. Citations: https://www.rsc.org/suppdata/d1/sc/d1sc06063e/d1sc06063e1.pdf https://www.rsc.org/suppdata/d1/ob/d1ob00093d/d1ob00093d1.pdf https://pubmed.ncbi.nlm.nih.gov/11028776/ https://synthose.com/products/EG773 https://www.glentham.com/en/products/product/GC7887/ https://www.bocsci.com/ethyl-3-4-di-o-benzyl-2-o-levulinoyl-b-d-thioglucuronide-benzyl-ester-item-1469.html https://synthose.com/products/EG124 https://www.bocsci.com/product/ethyl-4-o-allyl-3-6-di-o-benzyl-2-o-levulinoyl-cas-2904756-10-9-96362.html