Synthèse univoque du nitro-2 methoxy-3 benzofuranne et des naphtofurannes correspondants

3-Methoxyarenofurans were obtained from 3-counmaranone, from ts three corresponding isomeric naphtofuranones and from 7-methoxynaphtho[2,1-b]furan-1-one in good overall yields by carboxymethylation followed by saponification and subsequent decarboxylation, Their regioselective nitration in the 2-position was performed by successive treatment with t-butyllithium, trimethyltin chloride and tetranitromethane.     

Synthèse du benzoyl-3 chromanol-4 et du benzoyl-3 2H-chromène

Reaction between phenylvinylketone and salicylaldehyde under basic conditions gave a mixture of 3-benzoyl-4-chromanol and 3-benzoyl-2H-chromene. Their structures were determined on the basis of analytical and spectroscopic data.     

Synthèse et transformations de pyridopyrimidopyrimidines

A convenient one-step synthesis of a pyridoprimidopyrimidine system by means of the chloride of 1,3-dimethy1-4amino-5-amino-5-(N,N-dimethyliminiumchloromethine)uracil and substituted pyridines is studied and the title compounds are described.     

Synthèse du virensate de méthyle

Synthesis of Methyl Virensate The synthesis of methyl virensate (=methyl 4-formyl-3,8-dihydroxy-1,6,9-trimethyl-11-oxo-11H-dibenzo-[b, e][1,4]dioxepin-7-carboxylate; 18 ) by the condensation of the substituted β-orcinol and orcinol units 9 and 10 followed by formylation and demethylation of the depsidone 13 is described.     

Synthèse d'analogues furannique et nitro-2 furannique du benzo[e]pyrène

Pyreno[4,5-b]furan, a heterocyclic analogue of benzo[e]pyrene, and its 10-nitro derivative were prepared in six steps staring from 5-formyl-4-hydroxypyrene. These isomers of the previously described pyreno[1,2-b]-furan, pyreno[2,1-b]furan, 10-nitopyreno[1,2-b]furan and 10-nitropyreno-[2,1-b]furan are of particular interest due to their mutagenic activities.     

Synthèse d'analogues furanniques et nitro-2 furanniques du diméthyl-7,12 benzanthracène

A route to 1-formyl-2-hydroxy-9-methylanthracene and 1-formy 1-2-hydroxy-9,10-dimethylanthracene is desribed. These two aldehydes were further converted into mono- or dimethylanthra[2,1-b]furans, besides the corresponding acids and esters, by condensation with ethyl bromoacetate. The related mono- or dimethyl-2-nitroanthra[2,1-b]furans were also prepared by reaction between the above aldehydes and bromonitromethane, followaed by heating in toluene in the presence of p-toluene-sulfonic acid.     

Synthèse d'iodopyrroles

This article reports the synthesis of di- and triiodopyrroles by reduction of tetraiodopyrrole. A new synthesis of 4-iodo-3- formylpyrrole is described.     

Synthèse et propriétés des aroylhydrazones du benzoate d'éthyle. Synthèses d'hétéroscycles azotes

The aroylhydrazones of ethyl benzoate have been prepared in fair yield by the action of aroylhydrazines on ethyl benzimidate hydrochloride. These products give rise, quantitatively, at their melting point, to 5-aryl-2-phenyl-1,3,4-oxadiazoles, and, in the presence of hydrazine hydrate, in boiling 1-propanol to 4-amino-5-aryl-3-phenyl(4H)-1,2,4-triazoles (Yields 50%). The addition of methylmagnesium iodide to these products give aroylhydrazones of acetophenone.     

Synthèse et caractérisation du phosphate de hafnium comme échangeur d'ions

The preparation, crystalline structure, properties and behaviour of the hafnium bis (monohydrogen phosphate) monohydrate as a cationic exchanger have been studied. The crystalline product has been characterized by elemental analysis, X-ray Powder patterns, thermal analysis, photoelectron spectrometry and infra red spectroscopy. A layered structure in which the hafnium and phosphorus atoms are disposed in such a way as to form zeolitic-type cavities is suggested. The reversibility of the exchange with respect to sodium ions is discussed and can be related to the water content of the exchanger.     

Synthèse et structure de benzopyranno-1 triazines-1,2,4

Under basic conditions 2,2,6-trimethyl-3,4-chromanedione is cy8clised nto I-benzopyranno[4,3-e]triazin-3-one. In acetic meduum, semicarbazide hydrochloride and diketone provide the I-benzopyranno[4,3-e] and [3,4-e]triazin-3-ones. However, under the same conditions, the thiosemi-carbazide leads exclusively to the I-benzopyranno[4,3-e]triazine-3-thione. The structure of these compounds is in agreement with the ¹³C nmr spectra.     

Synthèse d'analogues furanniques du benzo[a]pyrène

We describe here the synthesis of 2-furan analogues of benzo[a]pyrene from 1-bromo-kpyrene, i.e., pyreno[1,2-b]furan and pyreno[2,1-b]furan, as well as that of their derivatives bearing a nitro group on the heterocycles.