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Synthesis of Galectin Inhibitors by Regioselective 3'-O-Sulfation of Vanillin Lactosides Obtained under Phase Transfer Catalysis.

ABSTRACT: Vanillin-based lactoside derivatives were synthetized using phase-transfer catalyzed reactions from per-O-acetylated lactosyl bromide. The aldehyde group of the vanillin moiety was then modified to generate a series of related analogs having variable functionalities in the para- position of the aromatic residue. The corresponding unprotected lactosides, obtained by Zemplén transesterification, were regioselectively 3'-O-sulfated using tin chemistry activation followed by treatment with sulfur trioxide-trimethylamine complex (Men₃N-SO₃). Additional derivatives were also prepared from the vanillin's aldehyde using a Knoevenagel reaction to provide extended ?, ?-unsaturated carboxylic acid which was next reduced to the saturated counterpart.

SUBMITTER: Belkhadem K

PROVIDER: S-EPMC7795656 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Synthesis of Galectin Inhibitors by Regioselective 3'-O-Sulfation of Vanillin Lactosides Obtained under Phase Transfer Catalysis.

Belkhadem Karima K Cao Yihong Y Roy René R

Molecules (Basel, Switzerland) 20201229 1

Vanillin-based lactoside derivatives were synthetized using phase-transfer catalyzed reactions from per-O-acetylated lactosyl bromide. The aldehyde group of the vanillin moiety was then modified to generate a series of related analogs having variable functionalities in the para- position of the aromatic residue. The corresponding unprotected lactosides, obtained by Zemplén transesterification, were regioselectively 3'-O-sulfated using tin chemistry activation followed by tre ...[more]

PMID: 33383774

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