Brown HT

Journal of Thermal Analysis and Calorimetry - Thermal behavior of Brown HT food dye was studied in correlation with the physical and biological antioxidant properties. Brown HT’s structure...     

Tartrazine: physical,thermal and biophysical properties of the most widely employed synthetic yellow food-colouring azo dye

Journal of Thermal Analysis and Calorimetry - The food-colouring dye tartrazine is a significant additive and in the same time a biologically active material. Thermal behaviour of trisodium...     

Supersymmetry breaking

We review the various mechanisms of supersymmetry breaking and its transmission to the observable sector. We argue that hybrid models where gauge dominates over gravity mediation, but gravity provides the main contributions to the Higgs sector masses and the neutralino mass, are able to combine the advantages and reduce the disadvantages of the two transmission mechanisms.      

A Novel Approach for the Synthesis of 5‐Pyridylindolizine Derivatives via 2‐(2‐Pyridyl)pyridinium Ylides

New indolizine derivatives were synthesized by an efficient one‐pot three‐component procedure starting from commercially available materials such as 2,2′‐dipyridyl, substituted bromoacetophenones, and electron‐poor alkynes in 1,2‐epoxybutane as reaction solvent and acid scavenger.     

Contributions to syntheses of pyrrolo[2,1-a]phthalazines

Abstract  

Structural elucidation of the dihydro derivatives obtained as by-products in the classic salt method synthesis of pyrrolo[2,1-a]phthalazines and acetylenic dipolarophiles was achieved by X-ray diffraction analysis of a representative compound. In addition, new pyrrolo[2,1-a]phthalazines were obtained by a one-pot three-component reaction that avoids the formation of the dihydro derivative intermediates.     

Generation of pyrrolo[2,1‐a]isoquinoline derivatives from N‐ylides: Synthetic control and structural characterization

New pyrrolo[2,1‐a]isoquinolines were obtained by two one‐pot procedures via 1,3‐dipolar cycloaddition between the isoquinolinium N‐ylides and symmetrical acetylenic dipolarophiles, avoiding the formation of dihydro intermediates. For structural comparison, the dihydro derivatives obtained by a classical two‐stage reaction were characterized by NMR and X‐ray crystallography, allowing complete stereochemistry assignments. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:723–729, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/.20740     

GUT precursors and fixed points in higher-dimensional theories

Within the context of traditional logarithmic grand unification atM _GUT ≈ 10¹⁶ GeV, we show that it is nevertheless possible to observe certain GUT states such asX andY gauge bosons at lower scales, perhaps even in the TeV range. We refer to such states as ‘GUT precursors’. Such states offer an interesting alternative possibility for new physics at the TeV scale, even when the scale of gauge coupling unification remains high, and suggest that it may be possible to probe GUT physics directly even within the context of high-scale gauge coupling unification. More generally, our results also suggest that it is possible to construct self-consistent ‘hybrid’ models containing widely separated energy scales, and give rise to a Kaluza-Klein realization of non-trivial fixed points in higher-dimensional gauge theories.