The natural all d- and/or unnatural all l-1,4- and 1,6-oligosaccharides were synthesized from furan alcohols using a palladium-catalyzed glycosylation reaction. The 1,4- and 1,6-alpha-manno-disaccharides were achieved in seven total steps starting from chiral furan alcohols. Similarly, 1,4- and 1,6-alpha-manno-trisaccharides were also synthesized in nine total steps. Key to the overall efficiency of this process was the use of highly diastereoselective palladium-catalyzed glycosylations, reductions, and dihydroxylations.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/ja039400n | DOI Listing |
Org Lett
January 2025
Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, Chemical Biology Research Center, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, People's Republic of China.
We present a versatile palladium-catalyzed glycosylation platform that enables facile access to structurally diverse N-O-linked glycosides with constantly excellent regio- and stereoselectivities. Importantly, this approach offers a broad substrate scope, low catalyst loadings, and outstanding chemoselectivity, allowing for the selective reaction of oximes/hydroximic acids over hydroxyl groups that would otherwise pose challenges in conventional glycosylation methods. The synthetic utility of this method is further exemplified through a range of synthetic transformations and late-stage modification of bioactive molecules.
View Article and Find Full Text PDFAdv Carbohydr Chem Biochem
November 2024
Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts, USA.
The various methods for the de novo asymmetric synthesis of the pyranose sugars are surveyed in this update of the 2013 Advances in Carbohydrate Chemistry and Biochemistry review. The survey begins with a general overview of the various de novo approaches to carbohydrates and defines the use of asymmetric catalysis for the de novo asymmetric synthesis of pyranoses. Next the application to pyranose-containing oligosaccharides is introduced via the use of a palladium-mediated glycosylation.
View Article and Find Full Text PDFChem Commun (Camb)
November 2024
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Herein we developed a palladium-catalyzed coupling of 2,3-enopyranose with arylboronic acid using a removable oxyacetamide directing group, which provides an efficient method for the synthesis of C-2 aryl sugars. The synthesized products were subsequently utilized as glycosyl donors in / glycosylation, enabling regio- and stereoselective production of 1,2-disubstituted branched sugars.
View Article and Find Full Text PDFJ Org Chem
November 2024
Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram Extension, Sitapur Road, P.O. Box 173, Lucknow 226031, India.
Herein, we describe a stereoretentive palladium-catalyzed cross-coupling between the in situ-generated glycosyl thiolate anion and diverse (hetero)aryl iodides at room temperature for creating the library of (hetero)aryl thioglycosides. The key to success is the judicious pairing of bis-electrophilic-nucleophilic partners with a variety of thioesters in an atom-economical way in which both the glycosyl thiolate anion and the acylium cation are incorporated into the final analogue. The advantage of this method is the acyl transfer on various nucleophilic partners, including a hydroxyl, a primary or secondary amine, an amino acid, and the biologically active hSGLT1 inhibitor.
View Article and Find Full Text PDFOrg Lett
August 2024
Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, Chemical Biology Research Center, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P. R. China.
An efficient and practical glycosylation platform for synthesizing -glycosides by leveraging palladium catalysis is disclosed. This approach enables facile access to diverse heterocyclic -glycosides with excellent regio- and stereoselectivities and high site selectivity of multiple N atoms. The reaction exhibits a broad substrate scope (65 examples), high functional group tolerance, and easy scalability.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!