Towards new nanoporous biomaterials: self-assembly of sulfopillar[5]arenes with vitamin D₃ into supramolecular polymers

Abstract

The ability of novel sulfopillar[5]arenes to form UV stable inclusion complex with cholecalciferol (vitamin D3) was shown.

Water-soluble pillar[5]arene sulfo-derivatives self-assemble into biocompatible nanosystems to stabilize therapeutic proteins

“…The introduction of thiafragments into the macrocyclic platform has been well studied for cyclodextrins, 30 calixarenes 31,32 and pillar [5]arenes. 33,20,21 However an important aspect of the reaction is overcoming the energy barrier to introduce the first and subsequent substituents. [34][35][36] It should be noted that the first stage of functionalization, to give the monosubstituted derivatives, has the greatest energy barrier.…”

“…Water-soluble macrocycle 5 was obtained by the direct thiolation method previously developed in our research group. 20 For this macrocycle 4 was introduced into a reaction with the bifunctional reagent sodium 2-mercaptoethanesulfonate in the presence of sodium hydride in dry DMF (Scheme 1). Thiolation proceeded at 90°C for 32 hours whereupon 5 was isolated in 95% yield.…”

“…The abilities of macrocycle 5, a decasulfo-substituted pillar [5]arene 6, 20 and an acyclic analog, 1,4-disulfo-substituted benzene 7, 21 to interact with therapeutic proteins was determined in buffer solutions (pH = 4.01; pH = 7.4 (physiological buffer); pH = 9.18) by UV-vis spectroscopy and dynamic light scattering (DLS) (Figure 1).…”

“…12 One class of macrocycles, the pillar [5]arenes, have been shown to fuctional as DDS components for anticancer drugs. [13][14][15][16][17] Pillar [5]arenes have a number of attractive characteristics, such as their ease of preparation and functionalization of the macrocyclic platform, 18 the controlled size of the macrocyclic cavity due to varying the length of substituents, 19 their low toxicity 20 and ability to dissolve in water. 21 The additional introduction of a fluorescent label into this platform allows them to be used as fluorescent sensors 22,23 for tumor imaging in photodynamic-photothermal therapy.…”

Cyclodextrin-pillar[n]arene hybridized macrocyclic systems

“…39 It will be very curious whether they could be combined together to construct integrated hybrid host systems and achieve enhanced functions in supramolecular chemistry or not. [40][41][42] For example, CD derivatives have inherent chiral cavities and can efficiently separate a wide range of enantiomeric organic substrates in aqueous solutions. 20,43 While pillar[n]arene just possesses a pair of enantiomeric conformers, which could rapidly interconvert in organic solution via the "oxygen-through-the-annulus" flipping of ring units (Chart 1).…”