Easy accessible isoxazol-5(4 H )-ones are useful precursors of heterocycles. In this context we report the ruthenium-catalyzed transformation 4-alkenyl-substituted isoxazol-5-ones to afford 1 -pyrrole derivatives. The operative conditions were proven be effective also on cyclohexane-fused isoxazolones giving 4,5,6,7-tetrahydroindoles. Reactions, which allow access tri-and tetra-substituted pyrr...

We present herein a new and efficient four-component synthesis of isoxazol-5(2H)-ones involving ring closing/Knoevenagel condensation/Michael addition sequential reactions.

A facile access to polysubstituted 3-(isoxazol-5-yl)pyrroles was developed through [3+2] cycloaddition of tosylmethyl isocyanide (TosMIC) and styrylisoxazoles. In the presence of KOH, various styrylisoxazoles reacted smoothly with tosylmethyl isocyanide and analogs to deliver a wide range of 3-(isoxazol-5-yl)pyrroles at ambient temperature. This transformation is operationally simple, high-yiel...

Die Frage, wie sich die RNA als ein Träger der genetischen Information entwickelt hat, ist von grundlegender Bedeutung für unser Verständnis des Ursprungs Lebens. Das RNA-Molekül viel zu komplex, das es in einem einzigen Evolutionsschritt hat entstehen können, was darauf hindeutet, dass Proto-RNAs (erste Vorläufer RNA) gegeben haben könnte, im Laufe Zeit heutigen haben. Hier zeigen wir, Isoxazo...

Human neutrophil elastase (HNE) is a potent serine protease belonging to the chymotrypsin family and is involved in a variety of pathologies affecting the respiratory system. Thus, compounds able to inhibit HNE proteolytic activity could represent effective therapeutics. We present here the synthesis of new thiazol-2-(3H)-ones as an elaboration of potent HNE inhibitors with an isoxazol-5-(2H)-o...

The synthesis and biological activities of a series of 3-(isoxazol-3-yl)oxymethyl cephalosporins are described. 7[2-(2-Aminothiazol-4-yl)-(Z)-2-methoxyiminoacetamido] -3[ (isoxazol-3-yl)oxymethyl]-3-cephem-4-carboxylic acid (7a) showedpotent activity against both Gram-positive and Gram-negative bacteria including some /3-lactamase producing species. Its pivaloyloxymethyl ester provided a good u...

The crystal structure of the title compound, C(16)H(16)FN(2)O(2) (+)·I(-), was determined as part of a study of the biological activity of isoxazolone derivatives as p38 mitogen-activated protein kinase (MAPK) inhibitors. The X-ray crystal structure of 4-[4-(4-fluoro-phenyl)-2-methyl-5-oxo-2,5-dihydro-isoxazol-3-yl]-1-methyl-pyridinium iodide showed the presence of the regioisomer 4-[3-(4-fluor...

1561 References Cited U.S. PATENT DOCUMENTS 3,792,423 2/1974 Becker et al. ......................... 73/620 3,979,712 9/1976 Ettenhofer et al. . 4,028,934 6/1977 Sollish ................................... 73/620 4,327,576 5/1982 Dickey et al. ................... 73/40.5 A 4,640,121 2/1987 Leuker et al. ................... 73/40.5 A 4,641,526 2/1987 Izumi et al. ........................... 73/5...