New β-keto ester substituted stilbene derivatives have been synthesized and cyclized with selenium electrophiles in the presence of Lewis acids. This now allows access to 1,2,3,4-tetrasubstituted naphthalene derivatives as cyclization and rearrangement products.

Oxidation of substituted imidazoles with modified Fenton's reagent (Fe(II), ascorbic acid, EDTA and H2O2) in aqueous solution at pH 5 -7 in the presence of inorganic orthophosphate gives high yields of an unknown bound phosphate, in the case of 2-methylimidazole up to 3 5 % based on inorganic phosphate. The dependence of the yields on reaction parameters and the hydrolytic behaviour of the comp...

The preparation and synthetic uses of a number of bifunctional reagents (5-chloro-2-trimethylstannyl-2-pentene and related substances, (~)-1-bromo-4-methyl-3-trimethylstannyl-2-pentene, and alkyl (z)and (~)-2,3-bis(trimethylstannyl)-2-alkenoates) are described. In this work a number of useful annulation methods were developed and these annulation sequences played key roles in effecting total sy...

[structure: see text]. Increased efficiency for ring-closing metathesis to form tetrasubstituted olefins using N-heterocyclic carbene ligated ruthenium catalysts was achieved by reducing the size of the substituents at the ortho positions of the N-bound aryl rings.

The three imidazole antimycotics clotrimazole, miconazole, and ketoconazole all inhibit the demethylation of lanosterol to ergosterol, resulting in inhibition of growth of Saccharomyces cerevisiae; this is a fungistatic action. At higher concentrations clotrimazole and miconazole are fungicidal, whereas ketoconazole is not. The fungicidal action reflects direct membrane damage by the imidazoles...

A short and efficient synthesis of 1,4-disubstituted imidazoles has been developed which provides the desired products with complete regioselectivity. This protocol allows preparation of compounds which are challenging to prepare by current literature methods in a regioselective fashion, a sterically and electronically diverse range of N-substituents being accessible. The sequence involves an u...

C3-Symmetric chiral trisimidazolines with m-chloroperbenzoic acid promoted the organocatalytic oxidation of N-sulfonyl ketimine. The present imidazoline catalysis produced oxaziridines bearing a tetrasubstituted carbon stereogenic center in high yields with up to 87% ee.

Enlarged tetrasubstituted alkenes with high fluorescent efficiency and good thermal stability are constructed. They exhibit luminance up to 35,160 cd m(-2) and efficiency of 16 cd A(-1) in OLEDs.

Elastin, a fibrous protein found in connective tissue is a hydrophobic, highly crosslinked insoluble protein. The study of its primary structure has been greatly hindered because no specific enzymatic or chemical method is known which would release a finite number of homogeneous peptides. Since the major crosslinks are tetrasubstituted pyridinium compounds, the (iso)desmosines [l] (1, fig.1) we...