Influence of methanol and cyclodextrin cavity size on stoichiometry and binding constant of 3-[2-(9-anthryl)benzoxazol-5-yl]-alanine

Mrozek, Justyna; Guzow, Katarzyna; Szabelski, Mariusz; Karolczak, Jerzy; Wiczk, Wiesław

doi:10.1016/s1010-6030(02)00269-1

“…The equilibrium constant K corresponding to the binding process of the ruthenium complex with the tetrameric and hexameric calixarenes (see eq 1) were determined by using the Benesi−Hidelbrand equation assuming a 1:1 calixarene−substrate association: where Δ A = I λ − I o . I o and I λ denote the absorption intensity of the ruthenium complex in the absence and presence of the calixarene, respectively, and β is a constant parameter which depends on the nature of the system studied.…”

Section: Resultsmentioning

confidence: 99%

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH₃)₅pz]²⁺ + Co(C₂O₄)₃^3-

Sánchez

¹

,

González-Jiménez

²

,

Fernández

³

et al. 2007

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The reaction [Ru(NH3)5pz]2+ + Co(C2O4)33- has been studied in aqueous solutions of p-sulfonatocalix[n]arene (n = 4, 6, and 8). The results are interpreted by using the pseudophase model. Results show that the rigidity and/or flexibility of the assembled rings have a great effect on the thermodynamics of inclusion of the guest into the host and, therefore, on the kinetics of the electron transfer processes that take place in these media. The obtained results are discussed from the viewpoint of two types of interactions: electrostatic and nonelectrostatic. From surface potential measurements, the guest-host interactions have been demonstrated to be mainly due to nonelectrostatic interactions, although the species are charged. So, the nonelectrostatic contribution to the equilibrium constant in all the calixarenes studied is 1 order of magnitude higher than the electrostatic one (Knel = 144 and 884 mol-1 dm3 for p-sulfonatocalix[n]arene (n = 4 and 6, respectively) and Kel approximately 10 mol-1 dm3). Electrostatic interactions also affect the kinetic results.

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Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

Ravi

¹

,

Pathigoolla

²

,

Balan

³

et al. 2023

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There is huge demand for developing guests that bind β‐CD and can conjugate multiple cargos for cellular delivery. We synthesized trioxaadamantane derivatives, which can conjugate up to three cargos per guest. 1H NMR titration and isothermal titration calorimetry revealed these guests form 1 : 1 inclusion complexes with β‐CD with association constants in the order of 103 M−1. Co‐crystallization of β‐CD with guests yielded crystals of their 1 : 1 inclusion complexes as determined by single‐crystal X‐ray diffraction. In all cases, trioxaadamantane core is buried within the hydrophobic cavity of β‐CD and three hydroxyl groups are exposed outside. We established biocompatibility using representative candidate G4 and its inclusion complex with β‐CD (β‐CD⊂G4), by MTT assay using HeLa cells. We incubated HeLa cells with rhodamine‐conjugated G4 and established cellular cargo delivery using confocal laser scanning microscopy (CLSM) and fluorescence‐activated cell sorting (FACS) analysis. For functional assay, we incubated HeLa cells with β‐CD‐inclusion complexes of G4‐derived prodrugs G6 and G7, containing one and three units of the antitumor drug (S)‐(+)‐camptothecin, respectively. Cells incubated with β‐CD⊂G7 displayed the highest internalization and uniform distribution of camptothecin. β‐CD⊂G7 showed higher cytotoxicity than G7, camptothecin, G6 and β‐CD⊂G6, affirming the efficiency of adamantoid derivatives in high‐density loading and cargo delivery.

show abstract

Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

Ravi

¹

,

Pathigoolla

²

,

Balan

³

et al. 2023

View full text Add to dashboard Cite

There is huge demand for developing guests that bind β‐CD and can conjugate multiple cargos for cellular delivery. We synthesized trioxaadamantane derivatives, which can conjugate up to three cargos per guest. 1H NMR titration and isothermal titration calorimetry revealed these guests form 1 : 1 inclusion complexes with β‐CD with association constants in the order of 103 M−1. Co‐crystallization of β‐CD with guests yielded crystals of their 1 : 1 inclusion complexes as determined by single‐crystal X‐ray diffraction. In all cases, trioxaadamantane core is buried within the hydrophobic cavity of β‐CD and three hydroxyl groups are exposed outside. We established biocompatibility using representative candidate G4 and its inclusion complex with β‐CD (β‐CD⊂G4), by MTT assay using HeLa cells. We incubated HeLa cells with rhodamine‐conjugated G4 and established cellular cargo delivery using confocal laser scanning microscopy (CLSM) and fluorescence‐activated cell sorting (FACS) analysis. For functional assay, we incubated HeLa cells with β‐CD‐inclusion complexes of G4‐derived prodrugs G6 and G7, containing one and three units of the antitumor drug (S)‐(+)‐camptothecin, respectively. Cells incubated with β‐CD⊂G7 displayed the highest internalization and uniform distribution of camptothecin. β‐CD⊂G7 showed higher cytotoxicity than G7, camptothecin, G6 and β‐CD⊂G6, affirming the efficiency of adamantoid derivatives in high‐density loading and cargo delivery.

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Influence of methanol and cyclodextrin cavity size on stoichiometry and binding constant of 3-[2-(9-anthryl)benzoxazol-5-yl]-alanine

Cited by 21 publications

References 32 publications

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH₃)₅pz]²⁺ + Co(C₂O₄)₃^3-

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH₃)₅pz]²⁺ + Co(C₂O₄)₃^3-

Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

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Influence of methanol and cyclodextrin cavity size on stoichiometry and binding constant of 3-[2-(9-anthryl)benzoxazol-5-yl]-alanine

Cited by 21 publications

References 32 publications

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH3)5pz]2+ + Co(C2O4)33-

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH3)5pz]2+ + Co(C2O4)33-

Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

Adamantoid Scaffolds for Multiple Cargo Loading and Cellular Delivery as β‐Cyclodextrin Inclusion Complexes

Contact Info

Product

Resources

About

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH₃)₅pz]²⁺ + Co(C₂O₄)₃^3-

Rigidity and/or Flexibility of Calixarenes. Effect of the p-Sulfonatocalix[n]arenes (n = 4, 6, and 8) on the Electron Transfer Process [Ru(NH₃)₅pz]²⁺ + Co(C₂O₄)₃^3-