Photochirogenic nanosponges: phase-controlled enantiodifferentiating photoisomerization of (Z)-cyclooctene sensitized by pyromellitate-crosslinked linear maltodextrin

Liang, Wenting; Zhao, Meiling; Wei, Xueqin; Yan, Zhiqiang; Wu, Wanhua; Caldera, Fabrizio; Trotta, Francesco; Inoue, Yoshihisa; Su, Dan; Zhong, Zhihui; Yang, Cheng

doi:10.1039/c6ra28211c

Cited by 12 publications

(8 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…MD is in widespread use because it is nontoxic even when consumed in excessive quantities and is inexpensive. Previous studies have shown that the gelling ability of κ-CRG can be improved by cross-linking CRG with MD [14][15][16]. Hence, we opined that MD is able to modify CRG's structure to reduce the brittleness of the capsules.…”

Section: Introductionmentioning

confidence: 85%

Characterization, Disintegration, and Dissolution Analyses of Carrageenan-Based Hard-Shell Capsules Cross-Linked with Maltodextrin as a Potential Alternative Drug Delivery System

Fauzi

Pudjiastuti

Hendradi

et al. 2020

International Journal of Polymer Science

View full text Add to dashboard Cite

Hard-shell capsules commonly consist of gelatin which is not a universal material considering it is extracted from animal parts. Moreover, the mad cow disease triggered the scrutinization of the use of gelatin in pharmaceutical products. Hence, an alternative to conventional hard-shell capsules is needed. Carrageenan- (CRG-) based hard-shell capsules were successfully prepared by cross-linking CRG with maltodextrin (MD) and plasticizing with sorbitol (SOR). These CRG-MD/SOR hard-shell capsules were produced as an alternative to conventional hard-shell capsules in the oral drug delivery system (DDS). The physical properties of CRG-MD/SOR capsules were characterized using the degree of swelling, FTIR, and SEM analyses. The disintegration and dissolution profile release of paracetamol from CRG-MD/SOR hard-shell capsules was performed in an aqueous medium with three different pH levels. The degree of swelling of CRG-MD/SOR was 529.23±128.10%. The main peaks in the FTIR spectrum of CRG-MD/SOR were at 1248, 930, 847, and 805 cm−1 for ester sulfate groups, 3,6-anhydrogalactose, galactose-4-sulfate, and 3,6-anhydrogalactose-2-sulfate, respectively. The SEM analysis exhibited minuscule pores on the surface of CRG and CRG-MD/SOR at 5000 times of magnification. The CRG-MD/SOR capsules required 18.47±0.11 min on average to disintegrate. The CRG-MD/SOR dissolution was better in a weakly acidic medium (pH 4.5) than in a strongly acidic (pH 1.2) and neutral (pH 6.8) media. Based on the aforementioned results, CRG-MD/SOR capsules are the potential candidate to replace conventional hard-shell capsules.

show abstract

Section: Introductionmentioning

confidence: 85%

Characterization, Disintegration, and Dissolution Analyses of Carrageenan-Based Hard-Shell Capsules Cross-Linked with Maltodextrin as a Potential Alternative Drug Delivery System

Fauzi

Pudjiastuti

Hendradi

et al. 2020

International Journal of Polymer Science

View full text Add to dashboard Cite

show abstract

“…Cyclodextrin-based nanosponges (βCD.NS) are the groups of hyper-branched polymers which can be obtained by the reaction of cyclodextrins with crosslinking reagents such as dialdehydes, dialkyl carbonates, carbonyldiimidazoles, epichlorohydrine, urethane, citric acid, diisocyanates, etc [1][2][3][4][5][6]. The inside cavity of cyclodextrins is hydrophobic, while the outer shell is highly hydrophilic, thus cyclodextrins 1 3 are able to form stable host-guest complexes with molecules of suitable polarity and size even in aqueous solutions [7,8], thereby these compounds have various applications in several fields such as catalysis, pharmaceuticals industries, biomedical, drug carrier systems, nanoreactors, molecular recognition, waste treatment, separation, electrochemical sensors, optical and electrical devices [9][10][11][12][13][14][15][16][17].…”

Section: Introductionmentioning

confidence: 99%

Hyper-cross-linked β-cyclodextrin nanosponge: a three-dimensional, porous and biodegradable catalyst in the one-pot synthesis of kojic acid-based heterocyclic compounds

2020

View full text Add to dashboard Cite

In the present study, β-cyclodextrin-based nanosponges were prepared by reaction of β-cyclodextrin with dicarbonyl imidazole as a crosslinker agent. The synthesized polycarbonate nanosponge was characterized by FT-IR spectroscopy, thermogravimetric analysis, scanning electron microscopy and Brunauer-Emmett-Teller. The catalytic activity of β-cyclodextrin-based nanosponges was successfully tested in the one-pot three-component condensation of kojic acid, aromatic aldehydes and various aromatic amines. The superiority of this new strategy is short reaction times, high yields and utilizing of biodegradable and nontoxic nanocatalyst.

show abstract

“…Manipulating the physical properties and chemical reactivity of organic molecules through non-covalent interactions is one of the most crucial goals in current photochemistry and supramolecular chemistry. , Through the formation of a supramolecular assembly, guest molecule(s) are spatially confined, orientationally aligned, conformationally restricted, and locally concentrated in the limited space of the host cavity to alter the original properties and reactivities. Indeed, (chiral) molecular hosts, such as cyclodextrins, cavitands, cucurbiturils, coordination cages, and hydrogen-bonding templates, have been employed for controlling excited-state properties and reactivities through supramolecular assembly to achieve substantial changes in chiroptical properties and stereochemical outcomes in chirality sensing and photochirogenesis. − …”

Section: Introductionmentioning

confidence: 99%

Supramolecular Photochirogenesis Driven by Higher-Order Complexation: Enantiodifferentiating Photocyclodimerization of 2-Anthracenecarboxylate to Slipped Cyclodimers via a 2:2 Complex with β-Cyclodextrin

Wei

Matsushita

et al. 2018

J. Am. Chem. Soc.

Self Cite

View full text Add to dashboard Cite

Chiral slipped 5,8:9',10'-cyclodimers were preferentially produced over classical 9,10:9',10'-cyclodimers upon supramolecular photocyclodimerization of 2-anthracenecarboxylate (AC) mediated by β-cyclodextrin (β-CD). This photochirogenic route to the slipped cyclodimers, exclusively head-to-tail (HT) and highly enantioselective, has long been overlooked in foregoing studies but is dominant in reality and is absolutely supramolecularly activated by 2:2 complexation of AC with β-CD. The intricate structural and photophysical aspects of this higher-order complexation-triggered process have been comprehensively elucidated, while the absolute configurations of the slipped cyclodimers have been unambiguously assigned by comparing the experimental and theoretical circular dichroism spectra. In the 2:2 complex, two ACs packed in a dual β-CD capsule are not fully overlapped with each other but are only partially stacked in a slipped anti- or syn-HT manner. Hence, they do not spontaneously cyclodimerize upon photoexcitation but instead emit long-lived excimer fluorescence at wavelengths slightly longer than the monomer fluorescence, indicating that the slipped excimer is neither extremely reactive nor completely relaxed in conformation and energy. Because of the slipped conformation of the AC pair in the soft capsule, the subsequent photocyclodimerization becomes manipulable by various internal or external factors, such as temperature, pressure, added salt, and host modification, enabling us to exclusively obtain the slipped cyclodimers with high regio- and enantioselectivities. In this supramolecularly driven photochirogenesis, the dual β-CD capsule functions as a chiral organophotocatalyst to trigger and accelerate the nonclassical photochirogenic route to slipped cyclodimers by preorganizing the conformation of the encapsulated AC pair, formally mimicking a catalytic antibody.

show abstract

Photochirogenic nanosponges: phase-controlled enantiodifferentiating photoisomerization of (Z)-cyclooctene sensitized by pyromellitate-crosslinked linear maltodextrin

Abstract: The enantioselectivity of the photoisomerization of (Z)-cyclooctene sensitized by the linear maltodextrin-based nanosponges are critically dependent on the phase properties.

Cited by 12 publications

References 46 publications

Characterization, Disintegration, and Dissolution Analyses of Carrageenan-Based Hard-Shell Capsules Cross-Linked with Maltodextrin as a Potential Alternative Drug Delivery System

Characterization, Disintegration, and Dissolution Analyses of Carrageenan-Based Hard-Shell Capsules Cross-Linked with Maltodextrin as a Potential Alternative Drug Delivery System

Hyper-cross-linked β-cyclodextrin nanosponge: a three-dimensional, porous and biodegradable catalyst in the one-pot synthesis of kojic acid-based heterocyclic compounds

Supramolecular Photochirogenesis Driven by Higher-Order Complexation: Enantiodifferentiating Photocyclodimerization of 2-Anthracenecarboxylate to Slipped Cyclodimers via a 2:2 Complex with β-Cyclodextrin

Contact Info

Product

Resources

About