Development of Urea Functionalised Synthetic Lectins

  • Claire S Webster

Student thesis: Doctoral ThesisDoctor of Philosophy (PhD)


Cellulose is the most abundant organic molecule on the planet, and is a key renewable resource, yet cannot be fully exploited due to its extreme insolubility in water. Whilst there are several synthetic lectins that can bind monosaccharides in water with good affinities, synthetic lectins for longer carbohydrate guests are rare. Recently, a synthetic lectin containing urea moieties has been reported to show excellent affinities and selectivity for all-equatorial guests and additionally, provide an increased cavity size which is favourable for longer guests. Therefore, these urea moieties have been incorporated into several receptor designs utilising tetraoxapentacene and pyrene surfaces, with the aim of binding cellulose derived polysaccharides. Five receptors were synthesised but unfortunately, only one (pyrene-TEB) was able to bind cellobiose, likely due to partially or fully closed cavities in water. However, the pyrene-pyrene receptors were repurposed and found to bind caffeine and other methylated xanthines with good affinities, and provided a ratiometric fluorescence response on binding. The main findings of this thesis highlight the requirement for sufficient steric bulk in the surface component to prevent free rotation of the urea groups leading to a collapsed cavity and thus low or no binding.
Date of Award25 Jan 2022
Original languageEnglish
Awarding Institution
  • The University of Bristol
SupervisorAnthony P Davis (Supervisor) & Craig P Butts (Supervisor)

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