Morita equivalence of quasi-primal algebras and sheaves

In this paper, we show that two quasi-primal algebras are Morita equivalent if and only if their inverse semigroups of inner automorphisms are isomorphic, and if they have the same one-element subalgebras. The proof of this statement uses the representation theory of algebras by sections in sheaves.Presented by H. P. Gumm.     

Synthesis of 3-thienyl-substituted isothiazolines-2 and 1,2,4-thiadiazoles based on nitrile sulfides of the thiophene series

The reaction of substituted - and -thienylcarboxamides with chlorocarbonylsulfenyl chloride gave 5-thienylsubstituted 1,3,4-oxathiazol-2-ones. Decarboxylation of the latter by heating in o-dichlorobenzene generated in situ - and -thienylnitrile sulfides, which in the presence of dipolarophiles [dimethyl fumarate, N-phenylmaleinimide, chloro(trichloro)acetonitrile] give the corresponding 3-thienyl-substituted ²-isothiazolines and 5-chloromethyl(trichloromethyl)-1,2,4-thiadiazoles.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1892–1897, August, 1992.     

Recent developments in manufacturing emulsions and particulate products using membranes

Membrane emulsification (ME) is a relatively new technique for the highly controlled production of particulates. This review focuses on the recent developments in this area, ranging from the production of simple oil-in-water (O/W) or water-in-oil (W/O) emulsions to multiple emulsions of different types, solid-in-oil-in-water (S/O/W) dispersions, coherent solids (silica particles, solid lipid microspheres, solder metal powder) and structured solids (solid lipid microcarriers, gel microbeads, polymeric microspheres, core-shell microcapsules and hollow polymeric microparticles). Other emerging technologies that extend the capabilities into different membrane materials and operation methods (such as rotating membranes, repeated membrane extrusion of coarsely pre-emulsified feeds) are introduced. The results of experimental work carried out by cited researchers in the field together with those of the current authors are presented in a tabular form in a rigorous and systematic manner. These demonstrate a wide range of products that can be manufactured using different membrane approaches. Opportunities for creation of new and novel entities are highlighted for low throughput applications (medical diagnostics, healthcare) and for large-scale productions (consumer and personal products).     

Degradation of polyhydroxyalkanoates in eutrophic reservoir

During the summers of 1999-2001 the dynamics of polyhydroxyalkanoate degradation in a small recreational eutrophic reservoir was studied experimentally. It has been shown that biodegradation of polyhydroxyalkanoates in the environment is determined by the structure and physicochemical properties of the polymer and by local weather conditions, which influence the state of the aquatic ecosystem. Species (clones) of bacteria able to utilize polyhydroxyalkanoates in the reservoir were identified using molecular phylogenetic analysis of 16S rRNA genes.     

Synthesis of 1,3,5-triazabicyclo[3.1.0]hexanes containing the fragments of α-amino acids and their esters at the N(3) atom

With 3,3-pentamethylene-1,2H-diaziridine as an example, it was shown that 3,3-dialkyl-1,2H-diaziridines can undergo cyclocondensation with -amino acids and their esters to give the corresponding N(3)-substituted 1,3,5-triazabicyclo[3.1.0]hexanes, including pure enantiomers.     

Phase equilibria up to the solidus line in the system Fe2WO6−Fe8V10W16O85

Phase equlibria in the solid state in the system Fe₂WO₆?Fe₈V₁₀W₁₆O₈₅ were studied by means of X-ray phase powder diffraction and differential thermal analysis, This system is one of the intersections of the three-component system Fe₂O₃?V₂O₅?WO₃. The investigation demonstrated that the system is not a real two-component system even below the solidus line.     

Synthesis,structure and reactions of seco-steroids containing a medium-sized ring—IX : Reactions of Δ1(10)-unsaturated 5-oxo-5,10-seco-steroids with hydroxylamine and n-methylhydroxylamine

When treated with hydroxylamine or N-methylhydroxylamine, in the presence of proton donor catalysts, trans-Δ¹⁽¹⁰⁾-unsaturated 5-oxo-5,10-seco-steroids, such as 3 (but not the corresponding diastereomeric cis-compounds), are converted stereospecifically and in good yield to isoxazolidine derivatives (e.g. 4 and 13), resulting from transannular 1,3-dipolar addition of the intermediately formed oximes and nitrones to the trans-double bond in the cyclodecene ring moiety of the seco-steroid system. Reactions are described and physical evidence is presented which establish the constitution and configuration of the isoxazolidine-containing cycloaddition products, and the mechanistic and steric course of this transannular ring closure process is discussed.     

Synthesis and Properties of 12(E)-Ethoxyimino Derivatives of 8-Aza-16-thiagona-12,17-diones

The reaction of 8-aza-16-thiagona-1,3,5(10),13-tetraene-12,17-dienes with ethoxyimine in dimethyl sulfoxide yields the corresponding 12(E)-ethoxyimino derivatives. The physicochemical properties of these compounds were studied.     

Natural Product Chemistry: From Plants to Human

Conventionally, natural product chemistry deals with the isolation, characterization, and synthesis of compounds from plants. It a broad sense, natural product chemistry may include all fields of biochemistry. Two projects are presented to illustrate the expanded definition of natural product chemistry. One deals with phosphatidylinositol (PI) and the key enzyme involved in its metabolism, PI-specific phospholipase C. The other project is on the structure-function relationship of human tumor suppressor p16.     

钩吻素子的全合成研究-具有19-C, 20-C双键、16-C氧代的蛇根精架的合成

本文报道L-色氨酸为原料, 采用我们新发展的立体专一性合成1,2,3,4-四氢-β-咔啉的方法, 通过Dieckmann反应, 合成了β-酮酯11。由11经Mn(III)/Cu(II)自由基环化反应, 首次成功地建立了具有19-C, 20-C双键、16-C氧代的蛇根骨架。