Synthèse d'acétyl-6 et benzoyl-6 indoles

The synthesis of 6-acetyl and 6-benzoylindoles has been carried out via the Hemetsberger reaction. Some aspects of their chemical reactivity were investigated.     

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 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 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.     

Synthèse de flavones et de xanthones dans la série du benzo[4,5]thiophène

We describe the first synthesis of 2-arylbenzo[4,5]thieno-[2,3-b]pyran-4-one and of 2-arylbenzo [4,5] thieno [3,2-b] pyran-4-one, from benzo [4,5] thiophene and we have extended these cyclizations to obtain the heterocyclic analogs of the xanthones.     

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 de nouveaux alkyl-2 et -3 tétrahydrofurannes et -pyrannes

New 2- and 3-alkyltetrahydrofurans or -pyrans were synthesized by various methods which can be extended to a larger series. These compounds include tertiary and quaternary α carbon substituted heterocycles, a very few of which were already known.     

Synthèse en monocristaux et structure du monouranate de sodium β-Na2UO4

β-Na₂UO₄ single crystals were synthesized from a melt with U, Nb, and Na ions. They are orthorhombic Fmmm with a = 5.802(2), B = 5.969(2), and c = 11.699(3) Å, and Z = 4. The structure was refined to R = 0.075 and R_w = 0.096 for 603 independent reflexions with I ≥ 3σ(I). The study shows that Na and O atoms are delocalized and that the structure results from the juxtaposition of four P2₁/b domains.     

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 de quelques alcoxy-2 et aryloxy-2 dioxolannes-1,3

2-Methoxy, 2-ethoxy, and 2,2-diethoxy-1,3-dioxolanes, substituted in the 4,5 and in the 2 position by methyl or phenyl groups were obtained by an uncatalyzed reaction between a vicinal diol and an orthoester. An acid catalyst (p-toluene sulfonic acid) was necessary in order to obtain the 2-phenyl-2-methoxydioxolanes. 2-Phenoxydioxolanes were prepared by an exchange reaction between phenol and the corresponding 2-ethoxydioxolane.     

Sur la synthèse d'alkoxy-2 nitro-3 2H-chroménes

2-Alkoxy-3-nitro-2H-chromenes have been obtained by the reaction of β-nitroacetaldehyde dialkyl acetals with some salicylic aldehydes in the presence of triethylamine p-toluene sulfonate.