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A rapid and simple method to access unnatural 2-substituted 5-thio oxazolines has been developed. This methodology is based on a Pummerer reaction followed by an intramolecular nucleophilic substitution, which changes the paradigm for the normal use of a base in Pummerer chemistry. We also provide a useful two-step method for the synthesis of the starting material and a mechanistic proposal based on experimental observations, which contests the previously proposed reaction pathway. The reaction proved to be general, and different substituents, such as alkyl, aryl, alkenyl and functionalized groups, can be used without a significant decrease in efficiency.

A simple method to access unnatural 2-substituted 5-thio oxazolines (II) from sulfoxides (I) is described.

1. The impacts of nutrients (phosphorus and nitrogen) and planktivorous fish on phytoplankton composition and biomass were studied in six shallow, macrophyte-dominated lakes across Europe using mesocosm experiments. 2. Phytoplankton biomass was more influenced by nutrients than by densities of planktivorous fish. Nutrient addition resulted in increased algal biomass at all locations. In some experiments, a decrease was noted at the highest nutrient loadings, corresponding to added concentrations of 1 mg L1 P and 10 mg L1 N. 3. Chlorophyll a was a more precise parameter to quantify phytoplankton biomass than algal biovolume, with lower within-treatment variability. 4. Higher densities of planktivorous fish shifted phytoplankton composition toward smaller algae (GALD

New amphiphilic graft copolymers were synthesized by means of a cationic ring-opening polymerization of 2-methyl-2-oxazoline initiated with a statistical copolymer of methyl methacrylate and chloromethylstyrene. The synthesis was carried out in benzonitrile at 110°C. The grafting reaction was quantitative and the yield of grafting was more than 90%percent;. The graft copolymers were characterized by means of NMR, FT-IR, and UV-VIS spectroscopy, as well as elemental analysis and viscosity measurements of their aqueous solutions. The graft copolymers revealed amphiphilic properties and evidence for the formation of micelles and molecular aggregates in aqueous solution. Graft copolymers with relatively short lateral chains are soluble in methanol but insoluble in water, while the copolymers with longer lateral chains are soluble in both methanol and water.

The graft copolymers poly[(isobutene-co-(m,p)-chloromethylstyrene)-g-ethyleneimine)] HPG1 and poly((m,p)-chloromethylstyrene-g-ethyleneimine) HPG2 were obtained through the alkaline hydrolysis of the amphiphilic graft copolymers poly[(isobutene-co-(m,p)-chloromethylstyrene)-g-2-methyl-2-oxazoline] and poly((m,p)chloromethylstyrene-g-2-methyl-2-oxazoline), respectively. The subsequent quaternization of HPG1 and HPG2 with methyl iodide resulted in new polyelectrolyte graft copolymers which are soluble in water despite of the hydrophobic backbone.

poly[isobutene-co-(p,m-chloromethylstyrene)]-graft-poly(2-methyl-2-oxazoline) graft copolymers (GP) were prepared by the “grafting from” method throught the cationic polymerization of 2-methyl-2-oxazoline (MeOXA) initiated by a statistical copolymer is isobutene and chloromethylstyrene. The unusual viscosity behavior in chloroform solution of these polymers, the dynamic laser light scattering analysis in aqueous solution, as well as the solubility in polar solvents like water and methanol demonstrate the amphiphilic character of the graft copolymers and indicate the formation of aggregates in solution.

Introduction and objectives. The routine medical check-up provides a good opportunity for screening workers early for cardiovascular risk factors. The aim of the present study was to investigate the prevalence of cardiovascular risk factors in the Spanish working population. Methods. The study included 216 914 working people (mean age 36.4 years, range 16-74 years, 73.1% male) undergoing routine medical check-up, which involved a structured questionnaire, physical examination, and standard serum biochemical analysis. Results. Cardiovascular disease had been diagnosed previously in 0.7% of workers, hypertension in 6.2%, diabetes in 1.2%, and dyslipidemia in 8.9%. Routine check-up showed that 49.3% (51.3% of males and 43.8% of females) were smokers, 22.1% (27.0% of males and 8.8% of females) had high blood pressure (≥140/90 mm Hg), 15.5% (18.3% of males and 13.3% of females) were obese (body mass index ≥30), 6.2% (7.8% of males and 1.9% of females) were hyperglycemic (blood glucose >110 mg/dL), and 64.2% had dyslipidemia (total cholesterol ≥200 mg/dL, LDL cholesterol ≥160 mg/dL, triglycerides ≥200 mg/dL, or HDL cholesterol

Fue sintetizado un macromonómero (M1) de 2-ciclopropil-2-oxazolina (Cicloxa) mediante la polimerización catiónica por apertura de anillo de la 2-ciclopropil-2-oxazolina iniciada por el clorometilestireno y en presencia de ioduro de sodio como catalizador. La reacción se llevó a cabo a 78°C en acetonitrilo. El macromonómero, homopolímero de ciclopropiloxazolina con un grupo vinilo en el extremo de la cadena polimérica, tuvo un grado de polimerización de 25 unidades monoméricas y un peso molecular de 2,912. El macromonómero tuvo sensibilidad a la temperatura teniendo un cambio conformacional (LCST) a los 18°C cuando esta disuelto en agua. El macromonómero permitirá, a través de su copolimerización con otros monómeros, la elaboración de nuevos polímeros sensibles a la temperatura del tipo copolímeros injertados e hidrogeles.