An adamantane-based disubstituted binding motif with picomolar dissociation constants for cucurbit[n]urils in water and related quaternary assemblies

Abstract

A binding motif based on 1,3-disubstituted adamantane binds cucurbit[8]uril and cucurbit[7]uril with respective values of pK = 12 and 11 to allow formation of quaternary assemblies with inverse arrangements.

Supramolecular Luminescent Sensors

“…Cyclodextrin binding affinities for small molecule guests are usually between 100 and 1000 M –1 . Cucurbiturils, by contrast, can have binding affinities as high as 10 14 or 10 15 M –1 , , which rivals the binding of avidin and biotin, which is among the strongest interactions known. , Second, cucurbiturils have a ring of carbonyls pointed at each entrance to the cavity. − These carbonyls are polarized to have negative electron charge density, and therefore cucurbiturils are much stronger cation binders than are cyclodextrins. Cucurbiturils show the strongest binding affinities in cases where they can bind molecules that are both cationic (in one portion), and hydrophobic (in a different portion), such as biogenic amines, which take full advantage of the structural features of the cucurbiturils.…”

Binding study on 1-adamantylalkyl(benz)imidazolium salts to cyclodextrins and cucurbit[n]urils

“…3-(3,5-Dimethyladamantan-1-yl)propionic acid (1.504 g, 6.36 mmol) was prepared from 1bromoadamantane according to the literature. 22,23 Subsequently, alcohol 6c was prepared according to a protocol reported by Babjaková et al 20 to get a colourless oil (1.267 g, 90 %). 1…”

“…We have reported several guests with terminal adamantane-based binding sites which were prepared via quaternisation using 1-adamantylmethyl iodide. 18,19,20 However, we faced serious synthetic difficulties, most likely related to the bulkiness of the adamantane cage, which disabled the preparation of some promising guests. Therefore, we decided to synthesise a series of model guests with an extended linker between the adamantane cage and cationic moiety.…”

Mechanism of sulfonation-induced chain scission of selectively oxidized polysaccharides

“…Besides, the C2 is known to be a preferred target for sulfonation reactions in cellulose (after C6) (Zhang, Brendler, Geissler, & Fischer, 2011). Initially, the model structure of DAC composed from twelve monomeric units in their most abundant form of intramolecular C3-O-C6 hemiacetal was optimized at B3LYP/6-31G(d,p) level of theory, which provided a good results in the past (Babjaková et al, 2016;Čablová et al, 2017). In the following step, the central unit of each structure was modified by C2-SO3H and C2-O-SO3H groups, respectively.…”