Search results for "Azole"

Antibakterielle wirkstoffe. VIII . Die aminomethinylierung in der reihe der aminothiazole

1982

Aus der die Umsetzung von 2-Amino-4-antipyrinyl-5-ethylthiazol (1) mit s-Triazin (2) und Pyrrolidin beinhaltenden Dreikomponentenreaktion geht das 4-Antipyrinyl-5-ethyl-2-[(4-pyrrolidinyl)methylenamino]thiazol (5) hervor. Struktur 5 last sich durch 1H- und 13C-NMR-Spektroskopie untermauern. The three-component reaction comprising the interaction of 2-amino-4-antipyrinyl-5-ethylthiazole (1) with s-triazine (2) and pyrrolidine leads to 4-anitpyrinyl-5-ethyl-2-[(4-pyrrolidinyl)methyleneamino]thiazole (5). Structure 5 is supported by 1H- and 13C-NMR spectroscopy.

ChemInform Abstract: Functionalization of 2-(1-Naphthyl)-5-phenyl-1,3,4-oxadiazole with Alkoxysilanes.

2010

ChemInform Abstract: A New and Effective Method to Carbazoquinocin C and Related Carbazole-3,4-quinones as Biological Antioxidants: Key Reactions of …

2001

Crystal Engineering Studies of the Complexes of Ethyl Resorcinarene with Aromatic Nitrogen Heterocycles

2003

Five X-ray structures of complexes of ethyl resorcinarene with aromatic nitrogen heterocycles (imidazole, 1,2,4-triazole, pyridine, pyrazine, 2-pyridylmethanol and quinoline) show that ethyl resorcinarene spontaneously forms molecular inclusion complexes with five- and six-membered aromatic nitrogen heterocycles via π π and CH π interactions. However, with 10-membered quinoline, no molecular inclusion complex is formed. Instead, quinoline manifests crystal lattice inclusion.

ChemInform Abstract: A New Method for the Regioselective Synthesis of β-Enamino Acid Derivatives.

2010

Abstract A mild, simple and efficient route to β-enamino imidazole carbonilic derivatives 3 by reaction of ketimines with N,N′ -carbonyl diimidazole in the presence of boron triflouride as catalyst has been developed. The conversion of 3 to esters has also been explored.

Synthesis and Reactivity of New β-Enamino Acid Derivatives:  A Simple and General Approach to β-Enamino Esters and Thioesters

1998

A new strategy has been developed for the synthesis of several β-enamino acid derivatives. N,N‘-Carbonyldiimidazole has been used as C-acylating agent of methyl ketimines, providing a direct and simple route to new β-enamino carbonyl imidazole derivatives 2. These derivatives 2 were cleanly and efficiently transformed into β-enamino esters 4 (X = O) and thioesters 4 (X = S) by reaction with a great variety of alcohols and thiols, including tertiary ones. Alternative and complementary routes to compounds 4 were also investigated. In addition, β-keto esters 6 have been obtained by mild acid hydrolysis of β-enamino esters 4.

Electrochemical determination of the stability of complexes formed by proton-ionizable ligands of 3,5-disubstituted 1H-pyrazole with phenethylamine

1999

The application of two extreme models for diffusion in two-component systems to electrochemically determine equilibrium constants is discussed. The application of cyclic voltammetric, diferential pulse and rotating-disc electrode voltammetric data to elucidate the stoichiometry and formation constant of complex species by applying a generalization of the molar-ratio method is described. Molar-ratio experiments permit the distinction between the limiting diffusive regimes. The values of the equilibrium stability constants for complexation of phenethylamine and phenethylammonium ions by a 26-membered dioxotetraester crown of 3,5-disubstituted 1H-pyrazole as free ligand 1[L] and as dipyrazolat…

ChemInform Abstract: On the Reactivity of Nitrosoimidazoles with Acids (the Cusmano-Ruccia Reaction): A Continuous Source of New Ring-into-Ring Inter…

2014

Abstract An extension of the ‘Cusmano–Ruccia’ reaction is reported. 6-(4-chlorophenyl)-3-methyl-5-nitrosoimidazo[2,1- b ]oxazole by the action of hydrochloric acid gives 3-(4-chlorobenzoyl)-5-methyl-1,2,4-oxadiazole ( 13 ); presumably via ammonium ion, CO 2 and methanol elimination. The relevance of the nature of the atom of the B -ring linked to C-2 of the imidazole for the occurrence of the ring-into-ring interconversion has been once more confirmed.

Mononuclear heterocyclic rearrangement. Part 6 . Studies on base catalysis of the rearrangement of the (Z)-p-nitrophenylhydrazone of 3-benzoyl-5-phen…

1981

1,2,4-Oxadiazole rearrangements involving an NNC side-chain sequence.

2009

The thermal rearrangement of N-1,2,4-oxadiazol-3-yl-hydrazones into 1,2,4-triazole derivatives is reported. This represents the first example of a three-atom side-chain rearrangement involving an NNC sequence linked at the C(3) of the oxadiazole. The reactions carried out under solvent-free conditions produced good to high yields of the final products.