Structural Insights into the Host–Guest Complexation between β-Cyclodextrin and Bio-Conjugatable Adamantane Derivatives

Abstract

Understanding the host–guest chemistry of α-/β-/γ- cyclodextrins (CDs) and a wide range of organic species are fundamentally attractive, and are finding broad contemporary applications toward developing efficient drug delivery systems. With the widely used β-CD as the host, we herein demonstrate that its inclusion behaviors toward an array of six simple and bio-conjugatable adamantane derivatives, namely, 1-adamantanol (adm-1-OH), 2-adamantanol (adm-2-OH), adamantan-1-amine (adm-1-NH2), 1-adamantanecarboxylic acid (adm-1-COOH), 1,3-adamantanedicarboxylic acid (adm-1,3-diCOOH), and 2-[3-(carboxymethyl)-1-adamantyl]acetic acid (adm-1,3-diCH2COOH), offer inclusion adducts with diverse adamantane-to-CD ratios and spatial guest locations. In all six cases, β-CD crystallizes as a pair supported by face-to-face hydrogen bonding between hydroxyl groups on C2 and C3 and their adjacent equivalents, giving rise to a truncated-cone-shaped cavity to accommodate one, two, or three adamantane derivatives. These inclusion complexes can be terminated as (adm-1-OH)2⊂CD2 (1, 2:2), (adm-2-OH)3⊂CD2 (2, 3:2), (adm-1-NH2)3⊂CD2 (3, 3:2), (adm-1-COOH)2⊂CD2 (4, 2:2), (adm-1,3-diCOOH)⊂CD2 (5, 1:2), and (adm-1,3-diCH2COOH)⊂CD2 (6, 1:2). This work may shed light on the design of nanomedicine with hierarchical structures, mediated by delicate cyclodextrin-based hosts and adamantane-appended drugs as the guests.

Nanoscale metal-organic frameworks for the delivery of nucleic acids to cancer cells

“…The decrease in particle concentration between unlabelled and Rh-labeled nanoMOFs could possibly be explained by the fact that a tiny fraction of the smallest labeled nanoMOFs are too dim to be detected, as previously reported ( Bourguignon et al, 2021 ; Pancani et al, 2018 ). It is worth noting that Ad-Rh could efficiently self-assemble with P-CD-M by the “host-guest” interaction between “Ad” and “β-CD” ( Wang et al, 2021 ). Similarly, no significant size variation was observed for the DNA-P-CD-M-Ad-Rh-nanoMOFs composites in comparison to empty nanoMOFs, confirming that the DNA loading and surface modification did not induce aggregation and the nanoMOF particles were well labeled by fluorescent moieties allowing for further tracking in cells.…”

Application research progress of cyclodextrin and its derivatives

“…Self-assembly in solution to form a two-dimensional supramolecular organic framework with a definite structure is a hot topic in supramolecular chemistry [12,17,22] .For this reason,Jiang Fengrui of Jilin University and others have designed and synthesized a new type of three-bridged cyclodextrin and dimerized boola-type azobenzene surfactant.Through the host-guest interaction between the two in aqueous solution,the first For example,a two-dimensional supramolecular organic framework with cyclodextrin as the main body,the chirality of the cyclodextrin can be transferred to the azobenzene molecule through the host-guest interaction.They also dynamically controlled the assembly and disassembly behavior of organic frameworks through ultraviolet light and visible light.This research has enriched the building blocks of supramolecular organic frameworks and opened up a new way for the synthesis and application of two-dimensional framework materials in the future.The research will be in the material [13][14][15] .…”

Water-Based Environmentally Friendly Pesticide Formulations Based on Cyclodextrin/Pesticide Loading System

“…CDs are a series of cyclic oligosaccharides, which made up by at least six α-D-glucopyranose units and up to 12 α-D-glucopyranose units, as discovered in 1981 by Villiers from starch degradation [21,22]. At present, relevant research has focused on α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), and hydroxypropyl-β-cyclodextrin (HP-β-CD), which is the derivative of β-CD and has excellent solubility in water [23][24][25]. The cavity of CD molecules is hydrophobic, whereas the outer surface is hydrophilic [26,27].…”