No abstract

in more extensive overlap of the 5 wave functions. As already mentioned, the crowding due to postdeposited Au atoms displaces CO molecules from their stable adsorption sites, which results in weakening of CO-metal bonds. This also contributes to the downward shift of the CO-induced peaks, since weakening of adsorption bonds reduces the relaxation energy, i.e., the energy due to the screening of produced holes by metal electrons.

Transmission infrared spectroscopy has been utilized to study the adsorption and thermal decomposition of (CF2H)20 on A1203. At 150 K the fluoro ether is adsorbed molecularly and reversibly via hydrogen bonding to isolated surface hydroxyl groups. The monolayer capacity was estimated to be ~3 X 10u molecules/cm1 2 judged by saturation effects in the IR spectra and correlation to an adsorption isotherm. The characteristic shape of the isotherm is indicative of associative interactions within the adlayer. The (CF2H)20 adsorbed at 150 K desorbs molecularly at higher temperatures, with the majority of the molecules desorbing by 250 K. As desorption progresses the isolated OH groups are regenerated on the surface; the original IR intensity of the isolated OH groups is regained only after heating to 500 K. Concomitant with the desorption process CA. P.B. is grateful for a supported educational leave from Alcoa.

When used in combination with azole antifungal drugs, cyclooxygenase (COX) inhibitors such as ibuprofen improve antifungal efficacy. We report the conjugation of a chiral antifungal azole pharmacophore to COX inhibitors and the evaluation of activity of 24 hybrids. Hybrids derived from ibuprofen and flurbiprofen were considerably more potent than fluconazole and comparable to voriconazole against a panel of Candida species. The potencies of hybrids composed of an S -configured azole pharmacophore were higher than those with an R -configured pharmacophore. Tolerance, defined as the ability of a subpopulation of cells to grow in the presence of the drug, to the hybrids was lower than to fluconazole and voriconazole. The hybrids were active against a mutant lacking CYP51, the target of azole drugs, indicating that these agents act via a dual mode of action. This study established that azole-COX inhibitor hybrids are a novel class of potent antifungals with clinical potential.

A ruthenium–carbon nanotube nanohybrid was employed as a catalyst in the tandem transformation of nitrochalcones into quinoline N‐oxides. Partial reduction of the nitro group to a hydroxylamine, followed by in situ intramolecular condensation to the carbonyl afforded the quinoline‐N‐oxides in satisfactory to good yields. Reduction of the nitro group was selective and independent of changes in the reaction conditions. Highlights of this method include a very low catalyst loading relative to that required for conventional methods for the synthesis of quinoline N‐oxides and mild reaction conditions.

An unprecedented reactivity of 3-sulfonylphthalide with 2-hydroxyaryl-p-quinone methides (HQMs) is reported here. A cascade of reactions starting with 1,6-addition and Dieckmann cyclization produced a diverse array of indenofurans and benzofurans...

[3+3] annulation of 1,3-binucleophilic indolin-2-thione with 1,3-bielectrophilic nitroallylic acetate via an SN2-reaction-6-endo-trig cyclization takes place with high regio- and stereoselectivity to afford tetrahydrothiopyranoindoles.

A supramolecular heterogeneous catalyst was developed by assembly and stabilization of gold nanoparticles on the surface of carbon nanotubes. A layer-by-layer assembly strategy was used and the resulting nanohybrid was involved in the catalytic oxidation of hydroxylamines under mild conditions. The nanohybrid demonstrated high efficiency and selectivity on hydroxylamine substrates.