The chemistry of heterocycles. IV. 2H-pyrido[4,3-e]-1,3-oxazine-2,4(3H)-dione,its precursors and some 3-substituted derivatives.

The preparation of 2H-pyrido[4, 3-e]-1, 3-oxazine-2, 4(3H)-dione (II) and the anisoyl, benzoyl, 4-chlorobenzoyl, trans-cinnamoyl, 3, 5-dinitrobenzoyl, 2-furoyl, and 2-naphthoyl derivatives substituted at position 3 of II together with their infrared and ultraviolet spectra are described. The 3-substituted 2 and 4-(2-pyridylethyl) and hydroxymethyl derivatives of quinolinimide and cinchomeronimide were also prepared and their spectra recorded.     

3-Phenacylidene-3,4-dihydro-1H-pyrido[2,3-b]pyrazin-2-ones and 2-Phenacylidene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-ones

Condensation of 2,3-diaminopyridine ( 1 ) with ethyl o-, m- and p-substituted benzoylpyruvates 2–9 gave two isomeric products. The preferential formation of one or the other isomer has been achieved by different reaction conditions. All the products appear to exist in the enamine form as evidenced by their ¹H nmr and ir spectra.     

Reaction of 2-dimethylaminomethylene-1,3-diones with Dinucleophiles. IV. Synthesis of 5,7-dihydrothiopyrano[3,4-c]pyrazol-4(1H)-ones, 5H-Thiopyrano[4,3-d]isoxazol-4(7H)-one and 6H-Thiopyrano[3,4-d]pyrimidin-5(8H)-ones

The reaction of 2H-thiopyran-3,5(4H,6H)-dione with N,N-dimethylformamide dimethyl acetal gave in good yield 4-dimethylaminomethylene-2H-thiopyran-3,5(4H,6H)dione (II), which afforded 1-substituted 5,7-dihydrothiopyrano[3,4-c]pyrazol-4(1H)-ones with aliphatic and aromatic hydrazines, 5H-thiopyrano[4,3-d]isoxazol-4(7H)-one (IV) with hydroxylamine hydrochloride and 2-substituted 6H-thiopyrano[3,4-d]pyrimidin-5(8H)-ones with amidines and guanidines, generally in satisfactory yields. 4-(t-Butylhydrazonoformyl)-2H-thiopyran-3,5(4H,6H)-dione was isolated as an intermediate in the reaction of II with t-butylhydrazine, whereas formamidine gave with II 4-iminoformyl-2H-thiopyran-3,5(4H,6H)-dione as the sole product. The isoxazole IV isomerized easily with sodium methoxide to 3,4,5,6-tetrahydro-5,5-dihydroxy-3-oxo-2H-thiopyrano-4-carbonitrile.     

New synthesis of 6,7-dihydro[1,3]thiazolo[2,3-f]purine-2,4(1H,3H)-diones

Russian Journal of Organic Chemistry -     

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.

     

Pyrrolopyrimidines. 5. Reaction of 6-Amino-1,3-dimethylpyrrolo[3,4-d]pyrimidine-2,4(1H,3H)-diones with 1,3-Diketones

The reaction of 6-amino-1,3-dimethylpyrrolo[3,4-d]pyrimidine-2,4-dione with 1,3-diketones leads to formation of predominantly pyrimido[4',5':3,4]pyrrolo[1,2-b]pyridazine-2,4(1H,3H)-diones and, to a lesser extent, pyrimido[5',4':3,4]pyrrolo[1,2-b]pyridazine-1,3(2H,4H)-diones. The ease and direction of the cyclization reaction suggests a very -electron rich pyrrole ring in the initial state, especially in the position 7.     

QSAR Study on Some N-[5-（2-Furanyl）-2-methyl- 4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-Substituted-5-（2-furanyl）-2-methyl-3H-thieno- [2,3-d]pyrimidin-4-ones Using Three-dimensional Holographic Vector of Atomic Interaction Field

Study on the quantitative structure-activity relationship （QSAR） of 26 compounds, N-[5-（2-furanyl）-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted- 5-（2-furanyl）-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones, with three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） was carried out. SMR-PLS QSAR models have been created and good correlation coefficients and cross-validated correlation coefficients were obtained. The result shows that the models have good prediction capability and favorable stability and the 3D-HoVAIF is applicable to the molecular structural characterization and biological activity prediction.     

Heterocyclization of functionalized heterocumulenes with C,N-and C,O-binucleophiles: VI. Synthesis of carbofused 2,3-dihydro-1,3-oxazin-4-ones and 3,4-dihydro-1,3-oxazin-2-ones

Condensations of 1-phenyl-2,2,2-trifluoro-1-chloroethyl isocyanate and 1-chlorobenzyl isocyanate with cyclic 1,3-diketones yield respectively carbofused 2,3-dihydro-1,3-oxazin-4-ones and 3,4-dihydro-1,3-oxazin-2-ones.     

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.