We have published an article in Chem. Sci. describing a cheap, low molecular weight glycosylation catalyst at loadings down to 0.1 mol%. Just 0.25 mg of thiouracil as catalyst was required to make 1 g of disaccharide product. The work evidences that the mechanism of activation is not through double H-bonding catalyst but rather by Brønsted acid/base catalysis. We also demonstrated application to the synthesis of glyconjugates and 1,1′-linked trehalose-type sugars (with relevance to TB studies).
Special congratulations to joint lead authors Gary and Avene; this paper contains key results from both their PhD theses and reflects a lot of hard work. Well done also to Mairead who contributed to the research as part of her final year BSc project. Ultimately a lot of hard work was put in by all the authors so well done too to Nathan and Ren, and thanks to Yannick for his work on special NMR experiments. Thanks also to our funders: SFI (SIRG and CDA awards supported Gary, Eoghan and Ren), IRC (PG Scholarship to Avene), and UCD (funding for Nathan).
The article is available as an open access article:
Chem Sci 2019, advance article. G A Bradshaw, A C Colgan, N P Allen, I Pongener, M B Boland, Y Ortin and E M McGarrigle* — Stereoselective organocatalyzed glycosylations – thiouracil, thioureas and monothiophthalimide act as Brønsted acid catalysts at low loadings. DOI: 10.1039/C8SC02788A