Synthesis of 2,7-disubstituted-5,6-dimethylpyrrolo-[2,3-d]-1,3-oxazin-4-ones as antifungal agents

A series of novel 5,6-dimethylpyrrolo[2,3-d]-1,3-oxazin-4-ones were synthesized from 2-amino-3-tert-butoxy-carbonyl-4,5-dimethylpyrroles. Two methods were used, cyclodehydration of 2-acylamino-3-carboxypyrroles with acetic anhydride and direct conversion of the 5,6-dimethylpyrrolo[2,3-d]-1,3-oxazin-2,4-diones to the title compounds with an anhydride directly providing the 2 substituent. Molecular modeling techniques revealed that these pyrrolo[2,3-d]oxazinones were rigid analogues of the allylamine antifungals. The compounds were tested for in vitro activity against Tricophyton and Scopulariopsis sp.     

Pyrano[4,3-d]pyrimidinium salts 4. Transformations of 5,7-diaryl-1,3-dimethyl-2,4-dioxo-1H,3H-pyrano[4,3-d]pyrimidinium bromides under the action of phenylhydrazines and aromatic acid hydrazides

Reactions of 5,7-diaryl-1,3-dimethyl-2,4-dioxo-1H,3H-pyrano[4,3-d]pyrimidinium bromides with phenylhydrazines and aromatic acid hydrazides have been studied. The reaction of the salts indicated with phenylhydrazine at ∼20 °C results in the pyrylium ring opening, whereas elevated temperature leads to recyclization products, i.e., 1,3-dimethylpyrido[4,3-d]pyrimidine-2,4(1H,3H)-diones. The reactions of the starting bromides with m-carboxyphenylhydrazine and aromatic acid hydrazides lead to 6-(R-amino)-1,3-dimethyl-2,4-dioxo-1H,3H-pyrido[4,3-d]-pyrimidinium salts.     

Electron ionization mass spectra of some 4β-phenyl-substituted cycloalkane-cis-fused 1,3-oxazin-2(3H)-ones, -2(3H)-thiones and 1,4-oxazepin-3(4H)-ones

The 70 eV mass spectra of 4β-phenyl-substituted cyclopentane- and cyclohexane cis-fused 1,3-oxazin-2(3H)-ones, the two related 2-thiones, 6,7-cis-trimethylene-5β-phenyl-1,4-oxazepin-3(4H)-one and its 2β-methyl derivative were recorded and their fragmentations examined by means of metastable ion analysis, collision induced dissociation technique and exact mass measurement. The fragmentation patterns of the 1,3-oxazin-2(3H)-ones were relatively simple: the favored formation of cycloalkene ions implied that a considerable proportion of the molecular ions might possess an enol structure. Changes in the size of the fused cycloalkane ring had little or no effect on the fragmentations. Instead, small changes in the heterocyclic part of the molecule caused remarkable effects on the fragmentation behavior. Compared to 1,3-oxazin-2(3H)-ones studied, both 1,3-oxazine-2(3H)-thiones and 1,4-oxazepin-3(4H)-ones showed much more complicated fragmentation patterns.     

Über die Synthese von substituierten 5-Phenyl-1H-thieno[2,3-e]1,4-diazepin-2(3H)-onen

Zusammenfassung Es wird die Synthese von in Stellung 6 und 7 mono- und dimethylsubstituierten 5-Phenyl-1H-thieno[2,3-e]1,4-diazepin-2(3H)-onen und ihre Methylierung in Stellung 1 beschrieben. Das Thienodiazepin5 b wurde außerdem in Stellung 7 chloriert, bromiert und nitriert.

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Synthesis of substituted 5-phenyl-1H-thieno[2.3-e]1.4-diazepin-2(3H)-ones

The preparation of in position 6 and 7 mono- and dimethylsubstituted 5-phenyl-1H-thieno[2.3-e]1.4-diazepin-2(3H)-ones and their methylation in position 1 are described. The thienodiazepine5 b was furthermore chlorinated, brominated and nitrated in position 7.

     

Über die Synthese von 5-Phenyl-1H-thieno[2,3-e]-1,4-diazepin-2(3H)-onen

Zusammenfassung Es wird die Synthese des 5-Phenyl-1H-thieno[2,3-e]-1,4-diazepin-2(3H)-ons (5), seine Alkylierung in Stellung 1, seine Chlorierung und Nitrierung in Stellung 7 und die N-Oxid-Bildung (in Stellung 4) beschrieben.

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Synthesis of 5-phenyl-1H-thieno[2.3-e]1.4-diazepin-2(3H)-ones

The preparation of 5-phenyl-1H-thieno[2.3-e]1.4-diazepin-2(3H)-one (5), its alkylation in position 1, its chlorination and nitration in position 7 and the N-oxide formation (in position 4) are described.

     

Synthesis of novel 1,3-oxazino[6,5-b]indole-2,4-(3H,9H)-dione and 2H-1,3,5-oxadiazino[3,2-a]indole-2,4-(3H)-dione from oxindoles

Two novel tricyclic ring systems were designed as serine protease inhibitors and synthesized from oxindoles; the first series, 1,3-oxazino[6,5-b]indole-2,4-(3H,9H)-diones, were prepared from 2,3-dihydro-2-oxo-(1H)-indole-3-carboxamides and phosgene in tetrahydrofuran with triethylamine. The second, a 2H-1,3,5-oxadiazino[3,2-a]indole-2,4-(3H)-dione was made using a similar cyclization on 2,3-dihydro-2-oxo-N-phenyl-(1H)-indole-1-carboxamide.     

Synthesis of 6-substituted 7-aryl-5,6-dihydropyrido[2,3-d]pyrimidine(1H,3H)-2,4-diones using the Vilsmeier reaction

The reaction of 6-amino-1,3-dimethyluracil with equimolar amounts of arylalkanone Mannich bases under optimized reaction conditions leads to 7-aryl-5,6-dihydropyrido[2,3-d]pyrimidines in a yield of 50-80%. Functionalization of these dihydropyridopyrimidine(1H,3H)-2,4-diones with the Vilsmeier reagent affords, depending on the reaction conditions, either 6-dimethylaminomethylidene substituted 5H-pyrido[2,3-d]pyrimidine(1H,3H)-2,4-diones or the corresponding pyridopyrimidine(1H,3H)-2,4-diones bearing a carboxaldehyde function in position 6 of the heterocycle. Some further transformations of the aldehyde function demonstrate the synthetic potential of the synthesized structures, introducing pharmacologically relevant basic substituents into the side chain of these pyrido[2,3-d]pyrimidine derivatives.     

[1,3]Dioxolo[5,6][1]benzothieno[2,3-c]-quinolin-6(5H)-ones

Summary The reaction of 3,4-methylenedioxycinnamic acid (1) with thionyl chloride resulted in the formation of 7-chlorothieno[2,3-f]-1,3-benzodioxole-6-carbonyl chloride (2) and cinnamoyl chloride (3). Subsequent reaction of the former withp-substituted anilines led to the formation of 7-chloro-N-(p-substituted phenyl)-thieno[2,3-f]-1,3-benzodioxole-6-carboxamides (4a–c) which on photocyclization afforded 2-substituted [1,3]dioxolo[5,6][1]benzothieno[2,3-c]quinolin-6(5H)-ones (5a–c) in fairly good yields and high purity. The structures have been confirmed by IR,¹H NMR, and analytical methods.Accepted for presentation at the Hong Kong International Symposium on Heterocyclic Chemistry (August 13–16, 1995)     

New [f]-fused xanthines: Synthesis of 1,3-dipropyl-1H,3H-pyrazino,pyrido, pyrimido and pyrrolo[2, 1-f]purine-2,4-diones

Synthesis of 1,3-dipropyl-1H,3H-pyrazino, pyrido, pyrimido and pyrrolo[2,1-f]purine-2,4-diones, starting from 5,6-diamino-1,3-dipropylpyrimidine-2,4-dione 1 and 6-chloro-1,3-dipropylpyrimidine-2,4-dione 14 is described. A new synthetic approach to 1,3-dipropyl-1H,3H-pyrido(or pyrazino)[1′,2′-1,2]pyrimido[4,5-d]pyrimidine-2,4,5-triones 19 e, f, h has been also developed.     

Synthesis of 3-alkoxycarbonylaminomethylcarbonylamino-4-benzoyl-1,2-dihydropyridines and their cyclization to 5-phenyl-1,3,8,9-tetrahydro-2H-pyrido[3,4-e]-1,4-diazepin-2-ones

The regiospecific reaction of 3-benzyloxycarbonylaminomethylcarbonylamino-4-benzoylpyridine (6a) , or 3-t-butoxycarbonylaminomethylcarbonylamino-4-benzoylpyridine (6b) , with either acetyl chloride or ethyl chloroformate, and either n-butylmagnesium chloride or phenylmagnesium bromide afforded the respective 1-acetyl (or ethoxycarbonyl)-2-n-butyl (or phenyl)-3-benzyloxy (or t-butoxy) carbonylaminomethylcarbonylami-no-4-benzoyl-1,2-dihydropyridines 7 in 60-75% yield. Reaction of 1-acetyl (or ethoxycarbonyl)-2-n-butyl (or phenyl)-3-t-butoxycarbonylaminomethylcarbonyl-4-benzoyl-1,2-dihydropyridines 7b, 7f, 7d, 7h with trifluoroacetic acid gave the corresponding 5-phenyl-8-acetyl (or ethoxycarbonyl)-9-n-butyl (or phenyl)-1,3,8,9-tetrahydro-2H-pyrido[3,4-e]-1,4-diazepin-2-ones 8a, 8b, 8c, 8d respectively in 45–63% yield. N¹-Methylation of 5-phenyl-8-acetyl-9-n-butyl (or phenyl)-1,3,8,9-tetrahydro-2H-pyrido[3,4-e]-1,4-diazepin-2-ones 8a, 8b using sodium hydride and iodomethane yielded the corresponding N¹-methyl derivatives 9a (48%) and 9b (54%). Oxidation of 5,9-diphenyl-8-ethoxycarbonyl-1,3,8,9-tetrahydro-2H-pyrido[3,4-e]-1,4-diazepin-2-one (8d) using p-chloranil afforded 1,3-dihydro-5,9-diphenyl-2H-pyrido[3,4-e]-1,4-diazepin-2-one (10) . 5-Phenyl-8-acetyl-9-n-butyl-1,3,8,9-tetrahydro-2H-pyrido[3,4-e]-1,4-diazepin-2-one (8a) and the corresponding 8-ethoxycarbonyl analog 8c exhibited weak anticonvulsant activity indicating that 8a and 8c may be acting at the same site as the 7-halo-1,4-benzodiazepin-2-one class of compounds.     

One-pot synthesis of chromeno[2,3-b]isoindolo[1,2-e]pyrrole-12,13-dione derivatives by sequential reaction of ninhydrin, 2-aminochromen-4-ones and arylamines

Stirring an equimolar mixture of ninhydrin 1 and 2-aminochromen-4-ones 2 in CH₃COOH at room temperature produced 6a,11a-dihydroxy-6H-chromeno[2,3-b]indeno[2,1-d]pyrrole-11,12(6aH,11aH)-diones 3, which on heating with aromatic amines 6 in acetic acid produced 11b-hydroxy-7-N-arylimino-6H-chromeno[2,3-b]isoindolo[1,2-e]pyrrole-12,13(11bH)-diones 7.     

Synthesis of 1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide

The reaction of methyl 2-bromo-6-(trifluoromethyl)-3-pyridinecarboxylate ( 1 ) with methanesulfonamide gave methyl 2-[(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridine-carboxylate ( 2 ). Alkylation of compound 2 with methyl iodide followed by cyclization of the resulting methyl 2-[methyl(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridinecarboxylate ( 3 ) yielded 1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 4 ). The reaction of compound 4 with α,2,4-trichlorotoluene, methyl bromopropionate, methyl iodide, 3-trifluoromethylphenyl isocyanate, phenyl isocyanate and 2,4-dichloro-5-(2-propynyloxy)phenyl isothiocyanate gave, respectively, 4-[(2,4-dichlorophenyl)methoxy]-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazine 2,2-dioxide ( 5 ), methyl 2-[[1-methyl-2,2-dioxido-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4-yl]oxy]propanoate ( 6 ), 1,3,3-trimethyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 7 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-[3-(trifluoromethyl)phenyl]-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 8 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-phenyl-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 9 ) and N-[2,4-dichloro-5-(2-propynyloxy)phenyl]-4-hydroxy-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2] thiazine-3-carboxamide 2,2-dioxide ( 10 ).     

Synthesis and anticonvulsant activities of 5-(2-Chlorophenyl)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepines

A group of 5-(2-chlorophenyl)-10-(substituted)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepines 7a-c were synthesized by the acid catalyzed reaction of 5-(2-chlorophenyl)-2-hydrazino-3H-pyrido[3,4-e]-[1,4]diazepine ( 6 ) with either trimethyl orthoformate, triethyl orthoacetate or triethyl orthobenzoate, respectively. 5-(2-Chlorophenyl)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7a ) and 5-(2-chlo-rophenyl)-10-methyl-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7b ) exhibited good anticonvulsant activity in the subcutaneous metrazol anticonvulsant screen which serves as a model for absence (petit mal) epilepsy.     

Five-membered 2,3-dioxoheterocycles: LXXXIV. [4+2]-Cycloaddition of styrene to 4,5-diaroyl-1H-pyrrole-2,3-diones. Crystal and molecular structures of 7a-(2,5-dimethylbenzoyl)-4-(2,5-dimethylphenyl)-1-(4-methoxyphenyl)-6-phenyl-7,7a-dihydropyrano[4,3-b]-pyrrole-2,3(1H,6H)-dione

1-Aryl-4,5-diaroyl-1H-pyrrole-2,3-diones react with styrene to form substituted 7,7a-dihydropyrano[4,3-b] pyrrole-2,3(1H,6H)-diones whose structure was confirmed by XRD analysis. The crystal and molecular structure of 7a-(2,5-dimethylbenzoyl)-4-(2,5-dimethyl-phenyl)-1-(4-methoxyphenyl)-6-phenyl-7,7a-dihydropyrano[4,3-b] pyrrole-2,3(1H,6H)dione was examined.     

One-Step Synthesis of Furo[2,3-d]Pyrimidine-2,4(1H,3H)-Diones Using the Can-Mediated Furan Ring Formation

The reaction of 1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione with various alkenes or terminal alkynes in the presence of cerium(IV) ammonium nitrate (CAN) afforded the corresponding 5,6-dihydrofuro[2,3-d]pyrimidine-2,4(1H,3H)-diones or furo[2,3-d]pyrimidine-2,4(1H,3H)-diones in moderate to good yields.     

Synthesis of 6-amino-2-aryl-1,2-dihydro-3H-pyrido[2,3-d]pyrimidin-4-one derivatives

This paper reports the synthesis of new pyrido[2,3-d]pyrimidin-4-one derivatives as diuretic agents. Starting with 1,2-dihydro-5-nitro-2-oxo-3-pyridinecarboxylic acid 1 , ethyl 2-ethoxy-5-nitro-3-pyridincarboxylate 4 was obtained. Compound 4 reacts with ammonia, methylamine or S-methylpseudothiourea to give the respective 2-amino-5-nitro-3-pyridinecarboxamide derivatives 5 and 6 or 2-methylthio-6-nitro-3H-pyrido[2,3-d]pyrimidin-4-one 8. Treating carboxamide 5 with arylaldehydes and zinc dichloride, new 2-aryl-1,2-dihydro-6-nitro-3H-pyrido[2,3-d]pyrimidin-4-ones 9 were synthetised. These compounds reduced with iron(II) hydroxide gave 6-amino-2-aryl-1,2-dihydro-3H-pyrido[2,3-d]pyrimidin-4-ones 10 as expected.     

Unambiguously confirmed structure of 2-phenacylidene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one and 3-phenacylidene-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-one

To determine the structures of two isomeric products, 2-phenacylidene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one (2) and 3-phenacylidene-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-one (3) obtained by condensation of 2,3-diaminopyridine (1) with ethyl benzoylpyruvate [1–3], these compounds were hydrolyzed to give 2-methyl-4H-pyrido[2,3-b]pyrazin-3-one (4) and 3-methyl-1H-pyrido[2,3-b]pyrazin-2-one (5) , respectively [4,5]. Both hydrolysates 4 and 5 were hydrogenated to afford 2-methyl-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one (6) and 3-methyl-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-one (7) . The latter compound was identical with an unequivocally synthesized compound providing proof for the structures of all these compounds.     

Über die Synthese von 7-Methoxycarbonyl-5-phenyl-1H-thieno[2,3-e]1,4-diazepin-2(3H)-on

The preparation of 7-methoxycarbonyl-5-phenyl-1H-thieno[2,3-e]1,4-diazepin-2(3H)-one (8) and its 1-methyl-derivative (10) is described. Hydrolysation of these two products yielded neither of the two possible acids3 respectively13.     

Synthesis of new imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-one derivatives by iodocyclization of 6-alkenyl(alkynyl)-aminopyrazolo[3,4-d]pyrimidin-4(5H)-ones

6-Allyl(diallyl, prop-2-yn-1-yl)amino-1-R-pyrazolo[3,4-d]pyrimidin-4(5H)-ones reacted with iodine to give angularly fused 8-iodomethyl-7,8-dihydro-1-R-imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-ones which were treated with sodium acetate to obtain 8-methylidene-1-R-7,8-dihydroimidazo[1,2-a]pyrazolo-[4,3-e]pyrimidin-4(6H)-ones as a result of elimination of hydrogen iodide. 8-Methylidene-1-R-7,8-dihydroimidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-ones were converted into 8-methyl-1-R-imidazo[1,2-a]pyrazolo-[4,3-e]pyrimidin-4(5H)-ones on heating to the melting point. 8-Methylidene-1-phenyl-7,8-dihydroimidazo-[1,2-a]pyrazolo[4,3-e]pyrimidin-4(6H)-one underwent isomerization into linearly fused 6-methyl-1-phenyl-1,8-dihydro-4H-imidazo[1,2-a]pyrazolo[3,4-d]pyrimidin-4-one on heating in sulfuric acid.     

Condensed as-triazines. Synthesis of 7-aryl-8H-[1,4]thiazino[2,3-e]-1,2,4-triazin-3(2H)-one

Ring closure of 6-amino-3-oxo-as-triazine-5-thione with α-haloketones provides the thiazino[2,3-e]-1,2,4-triazines which dehydrate via an unusual pathway to give 7-aryl-8H[1,4]thiazino[2,3-e]-1,2,4-triazin-3(2H)-ones.