Synthesis of b-Lewis b to investigate binding preferences of helicobacter pylori

<none>

Programme Social programme Plenary speakers Keynote speakers 1st EuroCarb Young Researcher (ECYR) Workshop CarboMet Workshop Mini symposium: Glycobiology at the LUMC and beyond Favourites/Agenda

Social programme

Plenary speakers

Keynote speakers

1st EuroCarb Young Researcher (ECYR) Workshop

CarboMet Workshop

Mini symposium: Glycobiology at the LUMC and beyond

Favourites/Agenda

Photos

Venue & Travel Venue Accommodation City of Leiden Travel directions

Venue

Accommodation

City of Leiden

Travel directions

Committees

Home

Synthesis of b-Lewis b to investigate binding preferences of helicobacter pylori

Mark Reihill 1 , Aisling Ní Cheallaigh 1 , Stefan Oscarson 1

1 School of Chemistry, University College Dublin, Dublin, Ireland

Helicobacter pylori, a Gram-negative bacterium found in the stomach, is a major cause of gastritis, peptic ulcers and stomach cancer.[1] The bacterium uses a membrane-bound lectin, Blood-group Antigen Binding Adhesin (BabA), to bind to Lewis b structures displayed on the surfaces of host cells.[2] By varying the pH of the environment of BabA, it was possible to change its binding preferences towards Lewis b structures.[3] Multivalent presentations of the Lewis b hexasaccharide, along with A- and B-Lewis b, will allow variable pH studies to be performed and determine how the binding preferences of BabA change.

A linear synthesis of B-Lewis b will be presented. Preparation of the heptasaccharide commenced with a 3’-OH lactoside acceptor, obtained via reductive ring-opening of a 3’,4’-endo-O-benzylidene acetal. NIS/AgOTf-promoted glycosylations yielded the desired 1,2-trans linkages while Lemieux’s halide-assisted glycosylation conditions were used to install the 1,2-cis linkages.[4] Upon global deprotection by Pd-catalysed hydrogenolysis, isothiocyanate methodology was employed to facilitate conjugation of the glycan to Bovine Serum Albumin (BSA).

Figure 1 – Lewis b structures attached to an amino-propyl hydrochloride spacer.

Graham, D. Y. Gastroenterology 1989, 96, 615–625.

Sweeney, E. G.; Guillemin, K. Cell Host Microbe 2016, 19, 5–7.

Bugaytsova, J. A. et al. Cell Host Microbe 2017, 21, 376–38.

Lemieux, R. U. et al. J. Am. Chem. Soc. 1975, 97, 4056–4062.

Contact eurocarb@eurocarb2019.com for general questions about EUROCARB2019, or codee@eurocarb2019.com for scientific questions.

Leiden University / Leiden Institute of Chemistry lic.leidenuniv.nl

European Carbohydrate Organisation

Congress by Design www.congressbydesign.com