The silver-catalysed reaction of simple ortho-alkynylsalicylaldehydes and alkenes gives complex benzo[de]chromenyl ketones through an unusual cascade process where the starting ortho-alkynylsalicylaldehyde behaves as a bis-diene derivative that participates in two different formal [4+2]-cycloaddition reactions.

A new glycosylation protocol employing ortho-(methyltosylaminoethynyl)benzyl glycosides as glycosyl donors and TMSOTf as the catalyst is disclosed. These donors can be readily prepared from the corresponding 'latent' ortho-iodobenzyl glycosides via a Sonogashira coupling, thus providing a new approach for the 'latent-active' synthesis of glycans.

We designed highly efficient porphyrin sensitizers with two phenyl groups at meso-positions of the macrocycle bearing two ortho-substituted long alkoxyl chains for dye-sensitized solar cells; the ortho-substituted devices exhibit significantly enhanced photovoltaic performances with the best porphyrin, LD14, showing J(SC) = 19.167 mA cm(-2), V(OC) = 0.736 V, FF = 0.711, and overall power conver...

Organocatalysis by N-heterocyclic carbenes is normally initiated the deprotonation of precursor azolium ions to form active nucleophilic species. Substituent effects on have an impact catalytic efficiency and provide insight into general mechanisms commonly used systems. Using NMR kinetic method for analysis C(3)-H/D exchange, we determined log kex–pD profiles three ortho-substituted N-aryl tri...

ortho-Quinones are produced in vivo through the oxidation of catecholic substrates by enzymes such as tyrosinase or by transition metal ions. Neuromelanin, a dark pigment present in the substantia nigra and locus coeruleus of the brain, is produced from dopamine (DA) and norepinephrine (NE) via an interaction with cysteine, but it also incorporates their alcoholic and acidic metabolites. In thi...

BACKGROUND Coadministration of oral contraceptives with protease inhibitors is complicated by drug interactions. An open-label three-period single-sequence study assessed the effect of coadministration of atazanavir (ATV)/ritonavir (RTV) with Ortho Tri-Cyclen(®) and with Ortho Tri-Cyclen(®) LO (Ortho-McNeil-Janssen Pharmaceuticals, Inc., Raritan, NJ, USA) on the pharmacokinetics (PK) of ethinyl...

A highly regioselective ruthenium-catalyzed ortho-arylation of substituted N-alkyl benzamides with aromatic boronic acids in the presence of [{RuCl(2)(p-cymene)}(2)], AgSbF(6), and Ag(2)O is described. Further, ortho-arylated N-alkyl benzamides were converted into fluorenones in the presence of trifluoroacetic anhydride and HCl.

Reactions of imidazoliums with palladacycles afforded NHC-palladacycle complexes. The reactivity of the NHC-palladacycles was explored and the results demonstrated that they could be template-directed ortho-aromatic metaloxylated in the presence of tert-butyl hydroperoxide (TBHP), affording (NHC)Pd(salicylaldimine)Cl complexes. Furthermore, the NHC-palladacycles showed efficient catalytic activ...

The synthesis, X-ray structure and electropolymerization of three new carbon-carbon linked di(2-thiophenyl)carboranes (, and ) are reported; the resulting polymers bearing icosahedral ortho-, meta- or para-carborane clusters show high thermal and electrochemical stabilities in comparison with unsubstituted polythiophene; the ortho-carborane-containing polymer has the highest conductivity of the...

The monodentate BINOL-derived phosphoramidite PipPhos is used as ligand for the iridium-catalyzed asymmetric hydrogenation of 2and 2,6-substituted quinolines. If tri-ortho-tolylphosphine and/or chloride salts are used as additives enantioselectivities are strongly enhanced up to 89%. NMR indicates that no mixed complexes are formed upon addition of tri-ortho-tolylphosphine.