Novel isomeric fluorine-boron complexes with donor-acceptor architecture have been efficiently synthesized and well characterized. Significant features, such as strong solid and liquid fluorescence, unusual large Stokes shifts, and lower LUMO levels and higher HOMO levels, are observed in these potential multifunctional molecules.

The photocatalytic activity for CO(2) reduction and optical and electrochemical properties of two Ru(II)-Re(I) binuclear complexes [Ru(dmb)(2)LRe(CO)(3)Cl](2+) (Ru-Re and Ru=Re, dmb = 4,4'-dimethyl-2,2'-bipyridine) with 1,2-bis(4'-methyl-2,2'-bipyridyl-4-yl)ethane and 1,2-bis(4'-methyl-2,2'-bipyridyl-4-yl)ethene as bridging ligands have been investigated. The conjugation content of the bridging ligands plays an important role in the photocatalytic behavior: a saturated linkage exhibited more efficient than the conjugated.

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Vinblastine (VLB) is one of vinca alkaloids with high cytotoxicity toward cancer cells approved for clinical use. However, because of drug resistance, toxicity, and other side effects caused from the use of VLB, new vinca alkaloids with higher cytotoxicity toward cancer cells and other good qualities need to develop. One strategy is to further study and better understand the essence why VLB possesses the high cytotoxicity toward cancer cells. In present work, by using molecular simulation, molecular docking, density functional calculation, and the crystal structure of α,β-tubulin complex, we find two modes labeled in catharanthine moiety (CM) and vindoline moiety (VM) modes of VLB bound with the interface of α,β-tubulin to probe the essence why VLB has the high cytotoxicity toward cancer cells. In the CM mode, nine key residues B-Ser178, B-Asp179, B-Glu183, B-Tyr210, B-Asp226, C-Lys326, C-Asp327, C-Lys336, and C-Lys352 from the α,β-tubulin complex are determined as the active sites for the interaction of VLB with α,β-tubulin. Some of them such as B-Ser178, B-Glu183, B-Tyr210, B-Asp226, C-Lys326, C-Asp327, and C-Lys336 are newly identified as the active sites in present work. The affinity between VLB and the active pocket within the interface of α,β-tubulin is -60.8 kJ mol(-1) in the CM mode. In the VM mode, that is a new mode established in present paper, nine similar key residues B-Lys176, B-Ser178, B-Asp179, B-Glu183, B-Tyr210, B-Asp226, C-Lys326, C-Asp327, and C-Lys336 from the α,β-tubulin complex are found as the active sites for the interaction with VLB. The difference is from one key residue C-Lys352 in the CM mode changed to the key residue B-Lys176 in the VM mode. The affinity between VLB and the active pocket within the interface of α,β-tubulin is -96.3 kJ mol(-1) in the VM mode. Based on the results obtained in present work, and because VLB looks like two faces, composed of CM and VM both to have similar polar active groups, to interact with the active sites, we suggest double-faces sticking mechanism for the binding of VLB to the interface of α,β-tubulin. The double-faces sticking mechanism can be used to qualitatively explain high cytotoxicity toward cancer cells of vinca alkaloids including vinblastine, vincristine, vindestine, and vinorelbine approved for clinical use and vinflunine still in a phase III clinical trial. Furthermore, this mechanism will be applied to develop novel vinca alkaloids with much higher cytotoxicity toward cancer cells.

A pH-responsive supramolecular nanoparticles was constructed through the electrostatic interaction from anionic sulfobutyl ether-β-cyclodextrin (SBE 7β-CD) and two positively charged chitosan (CS-75% and CS-95%). The prepared nanoparticles were characterized by UV-vis absorption spectra, x-ray diffraction, dynamic light scattering, transmission electron microscopy, and zeta potential. It was found that the CS/SBE 7-β-CD nanoparticles can be disassembly by increasing pH value and reassembled by reducing to the original pH value. To explore the potential of the obtained nanoparticles as a drug delivery vehicle, a negatively charged anticardio cerebrovascular drug sodium ferulate (SF) was loaded. The result indicated that the SF could be efficiently encapsulated in its nanoparticle nucleus under simulated gastric conditions with lower pH (pH 2.0), while effective release is triggered in a simulated intestinal environment with higher pH (pH 8.5). The assembly/disassembly behavior and drug loading/release property make CS/SBE 7-β-CD nanoparticles promising candidates for pH stimulation responsive drug delivery system, which has a broad application prospect in the treatment of cardiovascular and cerebrovascular diseases, diabetes and other chronic diseases.

Paclitaxel (PTX) is used to treat various cancers, but it also causes serious side effects and resistance. To better design similar compounds with less toxicity and more activity against drug-resistant tumors, it is important to clearly understand the PTX-binding pocket formed by the key residues of active sites on β-tubulin. Using a docking method, molecular dynamics (MD) simulation and density functional theory (DFT), we identified some residues (such as Arg278, Asp26, Asp226, Glu22, Glu27, His229, Arg369, Lys218, Ser277 and Thr276) on β-tubulin that are the active sites responsible for interaction with PTX. Another two residues, Leu371 and Gly279, also likely serve as active sites. Most of these sites contact with the "southern hemisphere" of PTX; only one key residue interacts with the "northern hemisphere" of PTX. These key residues can be divided into four groups, which serve as active compositions in the formation of an active pocket for PTX binding to β-tubulin. This active binding pocket enables a very strong interaction (the strength is predicted to be in the range of -327.8 to -365.7 kJ mol(-1)) between β-tubulin and PTX, with various orientated conformations. This strong interaction means that PTX possesses a high level of activity against cancer cells, a result that is in good agreement with the clinical mechanism of PTX. The described PTX pocket and key active residues will be applied to probe the mechanism of tumor cells resistant to PTX, and to design novel analogs with superior properties.

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Docetaxel (DTX) is an effective and commonly used chemotherapeutic drug for cancer.