Synthèse de nouveaux hétérocyeles indoliques

In this work we present a new aproch for the synthesis of tri aned tetracyclic heterocycles in the indole series.     

Synthèse de (3-aminopropyl)arylsilanes,comportant un ou deux motifs hétérocycliques,fongicides potentials

Synthesis of (3-Aminopropyl)arylsilanes, Including One or Two Heterocyclic Patterns, Potential Fungicides Flusilazole is an effective silylated fungicide used on a large scale for plant protection. We synthesized several flusilazole analogs and also copied the tebuconazole design, an other very efficient fungicide, which has four atoms between the aromatic group and the heterocyclic moiety. In contrast to flusilazole, we obtained dissymetric structures around the Si-atom by using successively two different Grignard reagents. In another way, the 1H-1,2,4-triazole moiety was exchanged in several cases by other N-heterocycles such as 1H-imidazole, piperidine, and 2,6-dimethylmorpholine, already present in other fungicidal compounds. Finally, several compounds having two N-heterocycles of the same or different nature were prepared.     

Synthèse photochimique de biaryles et hétérobiaryles à partir d'aryl-et hétéroarylamines,d'un nitrite d'alkyle et d'un substrat aromatique ou hétéroaromatique

Photochemical synthesis of biaryls and heterobiaryls from aryl and heteroarylamines, alkylnitrite and aromatic or heteromatic substrates The photochemical reaction of aromatic and heteroaromatic amines with excess t-butyl nitrite in aromatic solvents (benzene, p-xylene, mesitylene) and in hetero-aromatic solvents (furan, thiophene) leads to biaryls or heterobiaryls. t-Butyl nitrite is more convenient than isopentyl nitrite which gives by-products. This new method has been used to synthesize 28 compounds in 17 to 60% yield.     

Composés hétérocycliques à partir (testers cyaniques. 4. Synthèse de nouvelles aroxy-2 quinazolinones-4

The cyclisation of ethyl anthranilate and ethyl N-methyl-anthranilate with aryl cyanates, catalyzed by benzoic acid, provides a simple and general method in high yields for the synthesis of 2-aroxy-4-quinazolinones and 2-aroxy-l-methyl-4-quinazolinones.     

Un nouvel hétérocycle telluré: le benzisotellurazole-1,2. I. Synthèse et propriétés

Two different synthetic methods for 1,2-benzisotellurazole are described. The properties of this new heterocyclic system are compared with the analogous sulfur and selenium heterocycles.     

Synthèse de nouveaux composés hétérocycliques: Les diaza-4,5 pyrène,diaza-4,5 pyrène-4 N-oxyde et diaza-4,9 pyrène-4,9 di N-oxyde

4,5-Diazapyrene is prepared by electrochemical cyclization of 4,5-dinitrophenanthrene, which was obtained by cyclization of 2,2′-dinitrobiphenyl-6,6 -dicarboxaldehyde. The electrochemical cyclization of the latter compound leads to 4,9-diazapyrene 4,9-dioxide.     

Sur les orthoamino formyl quinoléines,nouveaux synthons hétérocycliques

The four o-aminoformylquinolines substituted on the pyridine ring were synthesized from the corresponding aminoquinoline-carboxylic acids. This convenient method was to used to prepare the four isomers and among them the 2-formyl-3-aminoquinoline which is not very stable. These new compounds provide new nitrogen-containing heterocyles having potential pharmaceutical properties.     

Synthèse d'acides acyl-3 ylidéne-5 tétroniques

A general synthetic route to new 3-acyl-5-ylidenetetronic acids by rearrangement in the presence of bases of 4-carbethoxy-2-ylidene[2H]-3-furanones 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 du tétraéthoxycarbonyl-1,1,6,6-cyclodécadiyne-3,8

A cyclisation of 1-bromo-5,5,10,10-tetraethoxycarbonyl-2,7-decadiyne ( 9b ) using NaH in dilute solution gives 1,1,6,6-tetraethoxycarbonyl-cyclodeca-3,8-diyne ( 8 ) in 17,6% yield. 9b is prepared by condensation of 1,1,6,6-tetraethoxycarbonyl-3-hexyne with 1,4-dibromo-2-butyne.     

Synthèse d'hétérocycles en catalyse par transfert de phase

A general study of the chemical behavior of heterocyclic anions, dianions and dianionic reagents under phase transfer catalysis conditions allowed us to synthesize various heterocyclic compounds such as imidazo[2,1-b]thiazole and derivatives; imidazo[2,1-b]thiazine and imidazo[2,1-b]benzothiazepine. Reaction conditions e.g., catalyst, solvent, temperature, etc., are indicated.     

Synthèse d'hétérocycles dérivés du (+)-camphre

Diamines react with 3-dimercaptomethylenecamphor giving either a bis-oxothioamide or a heterocyclic compound via in oxoaminothioamide intermediate. In this last reaction, there is cleavage of both C? S bonds. Similarly, diamines react with β-oxothioamides to produce the same heterocyclic derivatives. In these reactions, a transamination is involved and the carbonyl group of camphor is preserved. A distinctly different reaction occurs when the same camphor derivatives are treated with hydrazine; thioxo- alcoylamino- or arylaminoindazoles are then obtained. Ring closure occurs on the carbonyl carbon of the camphor molecule.     

Synthèse de systèmes comportant deux cycles thiophéniques orthocondensés à un hétérocycle à sept chainons

The reduction of the carbonyl group of bithienyls carrying on each thiophene ring a formyl group bonded to the carbon atom next to the intercyclic bond leads to the expected primary di-alcohols. These dialcohols can give the corresponding bis-halogeno-methylated bithienyls. The dehydration of the alcohols and the action of sodium sulfide or amines upon the obtained halides leads respectively to the dihydrodithieno[c,e] oxepines, thiepines and azepines. The tetramethyl derivatives of the previous oxepines have been obtained from diacetylbithienyls.     

Synthèse, à partir du (+) — camphre,d'hétérocycles dérives des tétrahydroxanthone,tétrahydroacridone,tétrahydroacridine et octahydroacridine

Derivatives of acridine, acridone and xanthone were prepared from (+)-camphor, 3-Arylidene, 3-arylmehtyl or 3-aroylcamphors with an halogen in the ortho position and dibornanonylarylmethanes may be uased aas precursors. Ring closure may be induced by ammonia, armoatic amines or potassium hydroxide with or without a catalyst. Good yaields were obtained. In come casaes, the reaction goes with an aromatisation of the heterocyclic moiety.     

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 d'hydroxyspirocétals insaturés et hétérocyclisation en méthyl-5 trioxa-2,6,11 tricyclo[5.3.1.01.5]undécane

The photochemical irradiation of unsaturated ketoacetals 4 gives unsaturated hydroxyspirocetals 6 . The mixture of these stereoisomers yields by thermal or ionic treatment a trioxatri-cyclo compound 7 .     

Synthèse de l'ériodermine

Synthesis of Eriodermin The total synthesis of eriodermin (=2,7-dichloro-4-formyl 3-hydroxy-8-methoxy-1,6-dimethyl-11H-dibenzo[b,e] [1,4]dioxepin-11-one) is described.     

Synthèse de céphalosporine-lactones

Condensation of azetidinones 2a and 2b with mercaptan 3 gave respectively compound 10 or a 1:1 mixture of 17 and 17 ′. Bromination of 10 , afforded cis and trans-bromohydrins 13a and of 17 and 17 ′ cis and trans-bromohydrins 18a . Acetylation and reduction with zinc and acetic acid of these bromohydrins gave cephems 4a or 4b and 4b ′ respectively.