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Photoelectron-imaging spectroscopy, flowing afterglow-photoelectron spectroscopy and the flowing afterglow-selected ion flow tube technique and electronic structure calculations are used for studying the mechanism of the reaction of the hydroxide ion (H[O.sup.-]) with 1H-1,2,3-triazole. Deprotonation of 1H-1,2,3-triazole at the C5 position has initiated fragmentation of the ring structure to yield a minor product, the ketenimine anion.

The synthesis and characterization of neutral heteroleptic molecular iridium(III) complexes with (2,4-difluoro)phenylpyridine and different pyridine-1,2,4-triazole ligands are described. The studies have shown high external quantum efficiencies and color points better than the standard for blue iridium(III) bis[(4,6-difluorophenyl)pyridinato-N,[C.sup.2]]picolinate.

Byline: E. N. Shapovalova (1), O. A. Shpigun (1), L. M. Nesterova (2), M. Yu. Belov (2) Abstract: The influence of the nature of the chiral selector and the composition of the mobile phase on the enantioselectivity of the separation of two fungicides of the triazole series by high-performance liquid chromatography was studied. The optimum conditions were selected for the separation of enantiomers with the use of cellulose tris-(3,5-dimethylphenylcarbamate) as the chiral selector (Chiralcel OD column) and hexane--isopropanol mixtures as the mobile phase. Samples of technical diniconazole (China) were analyzed. Author Affiliation: (1) Department of Chemistry, Moscow State University, Vorob'evy gory, Moscow, 119992, Russia (2) ZAO Avgust, ul. Tandera 6, Moscow, 128513, Russia Article History: Registration Date: 06/10/2004

The article explains introduction of broad-spectrum triazoles and a new class of antifungals, along with the other advances that has taken place in the antifungal therapy.

The synthesis and use of 1,5-disubstituted triazoles as cis-peptide bond mimics and the incorporation of 1,5- or 1,4-disubstituted triazoles into a protein are studied. The results have shown that Xaa-1,5-triazole-Ala modules can be used as viable mimics of Xaa-cis-Pro segments in proteins.

The adsorption of benzotriazole (BTAH) on Cu2O (III) was investigated using the first-principles density functional theory calculations. The results show that BTAH can be firmly chemisorbed onto the surface, and the chemisorption is due to the combined effect of a chemical bond with surface copper cation through nitrogen sp2 lone pairs and a hydrogen bond with a surface oxygen anion through C-H or N-H protons.

A novel one-pot procedure for the regio-controlled synthesis of allyltriazoles is developed by the use of nonactivated terminal alkynes, allyl carbonate and trimethylsilyl azide. The cooperative activity of palladium and copper catalysts plays a vital role in the present transformations.

A chain of new cadmium-triazole structures is synthesized via varying the different triazole ligands and anions. These structures vary from zero to three-dimensionality.

When persistent radical 1-(4-(N-tert-butyl-N-aminoxylphenyl)-1H-1,2,4-triazole reacts with M(hfac)2 cyclic M2L2 complexes are formed. This qualitative behavior is explicated in terms of spin polarization exchange between the metal sites through the organic radicals.

The special reactivity of the cationic metallocene complexes of the tetraphenylborate anion is used for expanding diazoalkane f element chemistry. The studies have shown that diazoalkanes are viable reagents not only for the transition metals, but also for the f elements, and the special nature of the f elements has led to different reactivity patterns.

A newly developed protocol is utilized using bimetallic catalyst for the selective synthesis of the piperidine derivative, a precursor of biological active muscarinic agonist. The reaction of the alkyne afforded the expected allyltriazole as the sole product in 51 percent yield under the same conditions.

Experiments with thiocarbonyl triazole derivatives suggest that the new glycoside synthesis may not be limited to imidazoles. Initial results, which demonstrate the generality of this concept in the context of hex-5-enyl and hept-6-enyl radical cyclizations with a variety of radical acceptors, are reported.

A site-specific methylation of 1,2,4-triazolate rings in ruthenium(II) complexes using OMe(sub 3)(super +)BF(sub 4)(super -) is described. The methylation takes place preferentially at the most sterically hindered nitrogen atom of the coordinated triazole ring.