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Photo-Fries rearrangements and associated photoreactions of four o-cresyl acylates were investigated in cyclohexane and in unstretched and stretched polyethylene (PE) films with different degrees of crystallinity. The esters differ in the number of phenyl substituents attached to the methyl group of
Hydrophobic bonding is central to many biochemical processes, such as protein folding and association. However, a complete description of the forces underlying hydrophobic interactions is lacking. The goal of this study was to evaluate the intrinsic energetic contributions of -CH(3), >CH(2), and
The objective of this study was to investigate porous chitosan-supported metal tetra(4-carboxyphenyl)porphyrin [Me TCPP/p-CTS] as a practical model for the structure and function of the hydrophobic pocket cavity in cytochrome P-450 enzyme. Porous and non-porous chitosan-supported Me TCPPs [Me
Using a recently developed quadratic response methodology for the calculation of frequency-dependent third-order properties of molecules in solution, we investigate the Buckingham birefringence of furan, thiophene, and selenophene in cyclohexane solution. These systems are chosen since accurate
Lipophilic guanilic derivatives (lipoGs) dissolved in organic solvents can undergo different self-assembly pathways based on different H-bonded motifs, e.g., the cyclic discrete G-quartet, which forms in the presence of alkali-metal ions, and the "infinite" tape-like G-ribbon observed in the absence
Adsorption of cyclohexane in pure silica zeolites was studied experimentally and by molecular simulations. Based on the adsorption isobars obtained from the quasi-equilibrated temperature adsorption and desorption (QE-TPDA) measurements and reported adsorption isotherms for high-silica zeolites Y,
Measurements of solubility and vapor pressure indicate that the cost of making a cavity in a nonpolar solvent that is large enough to accommodate a single water molecule is just balanced by the attraction between the water molecule and the walls of the cavity. As a result of this unexpected
The A-X electronic absorption spectra of cyclopentyl, cyclohexyl, and cyclohexyl-d(11) peroxy radicals have been recorded at room temperature by cavity ringdown spectroscopy. By comparing the experimental spectra with predictions from ab initio and density functional calculations, we have assigned
Benzene hydrogenation is one of important industrial processes. The reaction is incomplete, resulting in a mixture of benzene, cyclohexane and/or cyclohexene which have to be separated before the following reactions. The currently-used extractive and azeotropic distillations are operationally
It has been noted that the work of cavity creation in water exhibits a crossover behavior, in that its cavity size dependence changes from volume dependence for small cavities to area dependence for larger cavities [Lum, K.; Chandler, D.; Weeks, J. D. J. Phys. Chem. B 1999, 103, 4570]. It is shown
Ligand affinities can be optimized by interfacial cavity filling. A hollow (Phe43 cavity) between HIV-1 surface glycoprotein (gp120) and cluster of differentiation 4 (CD4) receptor extends beyond residue phenylalanine 43 of CD4 and cannot be fully accessed by natural amino acids. To increase HIV-1
We describe here the effects of aprotic solvents on the spectroscopic characteristics of bixin. Bixin was dissolved in dimethyl sulfoxide, acetone, dichloromethane, ethyl acetate, chloroform, dimethyl carbonate, cyclohexane and hexane, separately, and its spectra in the resulting solutions were
State change is a key phenomenon in materials science. We report the first observation of vapor-responsive reversible structural liquid-to-solid and solid-to-structural liquid state changes. We observed that a macrocyclic compound, a pillar[6]arene derivative bearing 12 n-hexyl substituents, is a
We have successfully prepared biocompatible and biodegradable hollow microspheres with sizes between 2 and 5 mum using cyclohexane droplets as a template and the N-methylated chitosan (NMC) cross-linked with glutaraldehyde (GA) as the shell. The structure, morphology, and formation process of the
The 6-, 9-, 12-, 15-, 18-, 21-, 24-, and 27-membered unsaturated thiacrown ethers 1-8 were formed by reaction of cis-1,2-dichloroethylene with sodium sulfide in acetonitrile. Crystal structures of 4-8 were determined by X-ray crystallography, and it was found that all sulfur atoms of 5-8 direct to