13028-54-1Relevant articles and documents
Carrier-Free Delivery of Precise Drug–Chemogene Conjugates for Synergistic Treatment of Drug-Resistant Cancer
Guo, Yuanyuan,Li, Yuehua,Qian, Qiuhui,Yan, Deyue,Zhang, Chuan,Zhu, Lijuan,Zhu, Xinyuan
, p. 17944 - 17950 (2020)
Combinatorial antitumor therapies using different combinations of drugs and genes are emerging as promising ways to overcome drug resistance, which is a major cause for the failure of cancer treatment. However, dramatic pharmacokinetic differences of drug
Very contracted to extended co -conformations with or without oscillations in two- and three-station ['2]daisy chains
Romuald, Camille,Busseron, Eric,Coutrot, Frederic
, p. 6516 - 6531 (2010)
The syntheses of various two- and three-station mannosyl [c2]daisy chains, based on a dibenzo-24-crown-8 macrocyclic moiety and an ammonium, a triazolium, and a mono- or disubstituted pyridinium amide station, are reported. The ability of these molecules to act as molecular machine based mimetics has been further studied by 1H NMR studies. In all the protonated ammonium states, the interwoven rotaxane dimers adopt an extended co-conformation. However, carbamoylation of the ammonium station led to many different other [c2]daisy chain co-conformations, depending on the other molecular stations belonging to the axle. In the two-station [c2]daisy chains containing an ammonium and a mono- or disubstituted pyridinium amide station, two large-amplitude relative movements of the interwoven components were noticed and afforded either an extended and a contracted or very contracted state with, in the latter case, an impressive chairlike conformational flipping of the mannopyranose from 1C4 to 4C1. In the case of the three-station-based [c2]daisy chains containing an ammonium, a triazolium, and disubstituted pyridinium amide, an extended and a half-contracted molecular state could be obtained because of the stronger affinity of the dibenzo-24-crown-8 part for, respectively, the ammonium, the triazolium, and the disubstituted pyridinium amide. Eventually, with axles comprising an ammonium, a triazolium, and a monosubstituted pyridinium amide, an extended conformation was noticed in the protonated state whereas a continuous oscillation between half-contracted and contracted states, in fast-exchange on the NMR time scale, was triggered by carbamoylation. Variations of the solvent or the temperature allow the modification of the population of each co-conformer. Thermodynamic data provided a small free Gibbs energy δG of 2.1 kJ·mol -1 between the two translational isomers at 298 K.
Controlling the chair conformation of a mannopyranose in a large-amplitude [2]rotaxane molecular machine
Coutrot, Frederic,Busseron, Eric
, p. 5186 - 5190 (2009)
Large-amplitude mannosyl [2]rotaxane molecular machines based on an anilinium and mono- or disubstituted pyridinium amide stations were synthesized. Dibenzo[24]crown-8 (DB24C8) initially resides around the anilinium station in both the cases. The mannosyl [2]rotaxane molecular machines 3a,b were successfully obtained from the initially prepared mannoside azide 1a,b containing a pyridinium amide moiety and the alkyne ammonium 2, by using the copper(I)-catalyzed Huisgen alkyne-azide 1,3-dipolar cycloaddition, also called CuAAC click chemistry. The interlocked architecture of glycorotaxanes 3a,b and 4a,b and the localization of the macrocycle at different pH were studied by 1H NMR spectroscopy. It was observed that the DB24C8 moved toward the pyridinium amide station upon deprotonation. However, with the disubstituted amide, DB24C8 forms hydrogen bonds with the pyridinium H7 atoms, which are located near the cationic nitrogen atom, and interacts by ion dipole contacts with the cationic charge.
A glutathione-responsive photosensitizer with fluorescence resonance energy transfer characteristics for imaging-guided targeting photodynamic therapy
Cao, Jing-Jing,Li, Xiao-Qiang,Liu, Jian-Yong,Xu, Gan,Yang, De-Chao,Zhang, Ming-Shan
, (2020)
Here, we have synthesized and characterized a novel activatable photosensitizer (PS) 8a in which two well-designed boron dipyrromethene (BODIPY) derivatives are utilized as the photosensitizing fluorophore and quencher respectively, which are connected by a disulfide linker via two successive Cu (?) catalyzed click reactions. The fluorescence emission and singlet oxygen production of 8a are suppressed via intramolecular fluorescence resonance energy transfer (FRET) from the excited BODIPY-based PS part to quencher unit, but both of them can be simultaneously switched on by cancer-related biothiol glutathione (GSH) in phosphate buffered saline (PBS) solution with 0.05% Tween 80 as a result of cleavage of disulfide. Also, 8a exhibits a bright fluorescence image and a substantial ROS production in A549 human lung adenocarcinoma, HeLa human cervical carcinoma and H22 mouse hepatoma cells having a relatively high concentration of GSH, thereby leading to a significant photocytotoxicity, with IC50 values as low as 0.44 μM, 0.67 μM and 0.48 μM, respectively. In addition, the photosensitizer can be effectively activated and imaged in H22 transplanted hepatoma tumors of mice and shows a strong inhibition on tumor growth. All these results suggest that such a GSH-responsive photosensitizer based on FRET mechanism may provide a new strategy for tumor-targeted and fluorescence imaging-guided cancer therapy.
Electron-Equivalent Valency through Molecularly Well-Defined Multivalent DNA
Cheng, Ho Fung,Wang, Shunzhi,Mirkin, Chad A.
supporting information, p. 1752 - 1757 (2021/02/06)
Oligonucleotide-functionalized nanoparticles (NPs), also known as "programmable atom equivalents"(PAEs), have emerged as a class of versatile building blocks for generating colloidal crystals with tailorable structures and properties. Recent studies have shown that, at small size and low DNA grafting density, PAEs can also behave as "electron equivalents"(EEs), roaming through and stabilizing a complementary PAE sublattice. However, it has been challenging to obtain a detailed understanding of EE-PAE interactions and the underlying colloidal metallicity because there is inherent polydispersity in the number of DNA strands on the surfaces of these NPs; thus, the structural uniformity and tailorability of NP-based EEs are somewhat limited. Herein, we report a strategy for synthesizing colloidal crystals where the EEs are templated by small molecules, instead of NPs, and functionalized with a precise number of DNA strands. When these molecularly precise EEs are assembled with complementary NP-based PAEs, X-ray scattering and electron microscopy reveal the formation of three distinct "metallic"phases. Importantly, we show that the thermal stability of these crystals is dependent on the number of sticky ends per EE, while lattice symmetry is controlled by the number and orientation of EE sticky ends on the PAEs. Taken together, this work introduces the notion that, unlike conventional electrons, EEs that are molecular in origin can have a defined valency that can be used to influence and guide specific phase formation.
MONOMER AND MULTIMERIC ANTI-HBV AGENTS
-
Page/Page column 143; 185-186, (2020/05/15)
The present invention is directed to compounds, compositions and methods for preventing, treating or curing hepatitis B (HBV) infection in human subjects or other animal hosts. The compounds are as also pharmaceutically acceptable, salts, prodrugs, and other derivatives thereof as pharmaceutical compositions and methods for treatment, prevention or eradication of HBV infection.
