The supramolecular host-guest complexation of Vemurafenib with β-cyclodextrin and cucurbit[7]uril as drug photoprotecting systems: A DFT/TD-DFT study

Spectrofluorometric investigations on the solvent effects on the photocyclization reaction of diclofenac

The solvent effects on the photochemical conversion rate of the photosensitizing drug diclofenac (DCF) were investigated using steady-state fluorescence spectroscopy. The spectral information obtained for the photochemical reaction of DCF in a set of neat solvents demonstrates that the photoconversion reaction rate of DCF is not only medium polarity dependent but also hydrogen-bonding dependent. The solvent effects were qualitatively and quantitatively assessed employing various solvatochromic models, including multi-parameter linear regression analysis (MLRA). Interestingly, the MLRA results (R = 0.99) revealed that the photoconversion rate increases with increasing solvent polarizability (π*) and H-bond donor capability (α), whereas the rate decreases with increasing hydrogen-bond acceptor capability (β). However, predominant effect of the solvent acidity compared to basicity and polarizability was observed. A hypothesis rationalizing the effects of H-bonding and medium polarity on DCF photoconversion reaction is presented and discussed.

Experimental and theoretical investigations of the effect of bis-phenylurea-based aliphatic amine derivative as an efficient green corrosion inhibitor for carbon steel in HCl solution

A novel bis-phenylurea-based aliphatic amine (BPUA) was prepared via a facile synthetic route, and evaluated as a potential green organic corrosion inhibitor for carbon steel in 1.0 M HCl solutions. NMR spectroscopy experiments confirmed the preparation of the targeted structure. The corrosion inhibitory behavior of the prospective green compound was explored experimentally by electrochemical methods and theoretically by DFT-based quantum chemical calculations. Obtained results revealed an outstanding performance of BPUA, with efficiency of 95.1% at the inhibitor concentration of 50 mg L-1 at 25 °C. The novel compound has improved the steel resistivity and noticeably reduced the corrosion rate from 33 to 1.7 mils per year. Furthermore, the adsorption study elucidates that the mechanism of the corrosion inhibition activity obeys Langmuir isotherm with mixed physisorption/chemisorption modes for BPUA derivatives on the steel surface. Calculated Gibb's free energy of the adsorption process ranges from -35 to -37 kJ mol-1. The SEM morphology analysis validates the electrochemical measurements and substantiates the corrosion-inhibiting properties of BPUA. Additionally, the eco-toxicity assessment on human epithelial MCF-10A cells proved the environmental friendliness of the BPUA derivatives. Density functional theory (DFT) calculations correlated the inhibitor's chemical structure with the corresponding inhibitory behavior. Quantum descriptors disclosed the potentiality of BPUA adsorption onto the surface through the heteroatom-based functional groups and aromatic rings.

Three-in-one: exploration of co-encapsulation of cabazitaxel, bicalutamide and chlorin e6 in new mixed cyclodextrin-crosslinked polymers

Three-in-one: a single bCyD polymer easily prepared in water is used to co-encapsulate cabazitaxel and bicalutamide with chlorin e6 affording a nanoplatform to implement multimodal cancer therapy.

Current Status of Quantum Chemical Studies of Cyclodextrin Host-Guest Complexes

This article aims to review the application of various quantum chemical methods (semi-empirical, density functional theory (DFT), second order Møller-Plesset perturbation theory (MP2)) in the studies of cyclodextrin host-guest complexes. The details of applied approaches such as functionals, basis sets, dispersion corrections or solvent treatment methods are analyzed, pointing to the best possible options for such theoretical studies. Apart from reviewing the ways that the computations are usually performed, the reasons for such studies are presented and discussed. The successful applications of theoretical calculations are not limited to the determination of stable conformations but also include the prediction of thermodynamic properties as well as UV-Vis, IR, and NMR spectra. It has been shown that quantum chemical calculations, when applied to the studies of CD complexes, can provide results unobtainable by any other methods, both experimental and computational.