A PASE-based approach towards 12-(1H-1,2,3-triazol-1-yl)-indolo[2,1-a]isoquinolines via the reaction of 3-(isoquinolin-1-yl)-1,2,4-triazines with benzyne

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Homotopy theory of associative rings

A kind of unstable homotopy theory on the category of associative rings (without unit) is developed. There are the notions of fibrations, homotopy (in the sense of Karoubi), path spaces, Puppe sequences, etc. One introduces the notion of a quasi-isomorphism (or weak equivalence) for rings and shows that—similar to spaces—the derived category obtained by inverting the quasi-isomorphisms is naturally left triangulated. Also, homology theories on rings are studied. These must be homotopy invariant in the algebraic sense, meet the Mayer-Vietoris property and plus some minor natural axioms. To any functor X from rings to pointed simplicial sets a homology theory is associated in a natural way. If X=GL and fibrations are the GL-fibrations, one recovers Karoubi-Villamayor's functors KVi, i>0. If X is Quillen's K-theory functor and fibrations are the surjective homomorphisms, one recovers the (non-negative) homotopy K-theory in the sense of Weibel. Technical tools we use are the homotopy information for the category of simplicial functors on rings and the Bousfield localization theory for model categories. The machinery developed in the paper also allows to give another definition for the triangulated category kk constructed by Cortiñas and Thom [G. Cortiñas, A. Thom, Bivariant algebraic K-theory, preprint, math.KT/0603531]. The latter category is an algebraic analog for triangulated structures on operator algebras used in Kasparov's KK-theory.     

2-Azaanthracene (microreview)

Chemistry of Heterocyclic Compounds - Microreview focuses on the main modern synthetic approaches toward 2-azaanthracene and its derivatives. These approaches are: inverse electron-demand...     

Design and Synthesis of Some New Benzimidazole Containing Pyrazoles and Pyrazolyl Thiazoles as Potential Antimicrobial Agents

A new class of bis heterocycles‐benzimidazolyl pyrazoles were prepared from the Michael acceptor (E)‐3‐(1H‐benzimidazol‐2‐yl)‐1‐aryl‐prop‐2‐en‐1‐one. The thiamide group was exploited to develop thiazole ring on treatment with p‐fluorophenacyl bromide to get tris heterocycles. All the lead compounds were tested for antimicrobial activity. The compound 7d having nitro substituent on the aromatic ring showed greater antimicrobial activity particularly against Pseudomonas aeruginosa and Penicillium chrysogenum.     

Parallelization of the algorithm of asymptotic partial domain decomposition in thin tube structures

The method of asymptotic partial domain decomposition for thin tube structures (finite unions of thin cylinders) is revisited. Its application to the Newtonian and non-Newtonian flows in great systems of vessels is considered. The possibility of a parallelization of its algorithm is discussed for linear and non-linear models.     

Thermo-diffusion in inertially confined plasmas

In a plasma of multiple ion species, thermodynamic forces such as pressure and temperature gradients can drive ion species separation via inter-species diffusion. Unlike its neutral mix counterpart, plasma thermo-diffusion is found comparable to, or even much larger than, baro-diffusion. It is shown that such a strong effect is due to the long-range nature of the Coulomb potential, as opposed to short-range interactions in neutral gases. A special composition of the tritium and ³He fuel is identified to have vanishing net diffusion during adiabatic compression, and hence provides an experimental test in which yield degradation is minimized during ICF implosions.     

Constructions of almost secure frameproof codes with applications to fingerprinting schemes

This paper presents explicit constructions of fingerprinting codes. The proposed constructions use a class of codes called almost secure frameproof codes. An almost secure frameproof code is a relaxed version of a secure frameproof code, which in turn is the same as a separating code. This relaxed version is the object of our interest because it gives rise to fingerprinting codes of higher rate than fingerprinting codes derived from separating codes. The construction of almost secure frameproof codes discussed here is based on weakly biased arrays, a class of combinatorial objects tightly related to weakly dependent random variables.