New organic nitrates. II. Synthesis of 2H-pyrido[2,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazin-4(3H)-ones, 2H-thieno[2,3-e]-1,3-oxazin-4(3H)-ones and 2H-thieno[3,4-e]-1,3-oxazin-2,4(3H)-diones

The preparation and the physico-chemical characterization of 2H-pyrido[2,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazine-2,4(3H)-diones, 2H-pyrido[4,3-e]-1,3-oxazin-4(3H)-ones, 2H-thieno[2,3-e]-1,3-oxazin-4(3H)-ones and 2H-thieno[3,4-e]-1,3-oxazine-2,4(3H)-diones are reported.     

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.     

[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)     

Synthesis of 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-4-ones

A Darzens condensation of α-chloroacetamide with aromatic aldehydes furnished a series of 3-aryl-2,3-epoxypropionamides, which were further converted to 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-2-ones.     

Synthesis of 6H,8H-isoquino[2,3-c][1,3]benzothiazin-8-ones

6H,8H-Isoquino-1,3-benzothiazin-8-ones have been prepared by reaction of 6,7-dimethoxy-2H-1,3-benzo-thiazines with homophthalic anhydride and by photocyclization of 3-benzoyl-4-methylene-6,7-dimethoxy 2H-1,3-benzothiazine. The compounds are thia analogues of protoberberine alkaloids containing a sulfur atom at C-5 and a lactam function at C-8. The mass spectra of the title compounds are discussed.     

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.     

Novel synthesis of 5,11-dihydro-6H-pyrido[2,3-b]-[1,4]benzodiazepin-6-ones and related studies

5,11-Dihydro-6H-pyrido[2,3-6][1,4]benzodiazepin-6-one (1), a basic intermediate in the preparation of 11-α-aminoacetyl derivatives with important biological activities, has been obtained by a three-step synthesis starting from easily available isatoic anhydride and anhydro ornithine. Some model cyclisation reactions leading to 5-member ring derivatives 10 and 12 instead of 7-member ring analogues of 1 , are reported. Easy transformations of the tetrahydro congener of 1 , i.e., compound 4 into 19 , which actually represents a tetrahedral intermediate in the transformation of 5 into 4 , is noticed. Further rearrangement of 19 into spiro compound 20 , and return of the latter into 5 is described.     

Synthesis of 2-Aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones and 7-Aryl-2,3,6,7-tetrahydro-5H-imidazo[2,1-b]-1,3-thiazin-5-ones

The reaction of 2-mercaptobenzimidazole, 5-ethoxy-2-mercaptobenzimidazole, and 2-mercaptoimidazoline with cinnamoyl chloride, its derivatives, and heteroanalogs was studied. Convenient methods were found for the synthesis of 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones and 7-aryl-2,3,6,7-tetrahydro-5H-imidazo[2,1-b]-1,3-thiazin-5-ones.     

Synthesis of 2-aryl-oxazolo[4,5-c]quinoline-4(5H)-ones and 2-aryl-thiazolo[4,5-c]quinoline-4(5H)-ones

[reaction: see text] Novel and highly efficient syntheses of oxazolo[4,5-c]quinoline-4(5H)-ones (1) and thiazolo[4,5-c]quinoline-4(5H)-ones (2) from ethyl 2-chlorooxazole-4-carboxylate (4) and ethyl 2-bromo-5-chlorothiazole-4-carboxylate (13), respectively, are described.     

Novel heterocycles. I. Synthesis and reactions of 6,7-dihydro-1H,3H,5H-pyrido[3,2,l-ij] [3,1]benzoxazine-1,3-dione

6,7-Dihydro-1H,3H,5H-pyrido[3,2,l-ij][3,1 ]benzoxazine-1,3-dione ( 1b ) was synthesized by a new route and its reactions with various nueleophiles are described.     

无溶剂一锅法合成新型8-芳基-7,8-二氢-[1,3]二氧戊环并[4,5-g]喹啉-6(5H)-酮类化合物

采用微波辅助,经三组分(3,4-亚甲二氧基苯胺,2,2-二甲基-1,3-二氧六环-4,6-二酮和取代芳醛)无溶剂一锅法合成了10个新型的8-芳基-7,8-二氢-[1,3]二氧戊环并[4,5-g]喹啉-6(5H)-酮类化合物,产率75.7%~83.5%,其结构经1H NMR,FT-IR,ESI-MS和元素分析表征。     

4,5-dihydro-6h-pyrrolo[1,2,3-d,e]quinoxalin-5-ones

The synthesis of 1-R¹-2-R²-8-R³-4,5-dihydro-6H-pyrrolo[1,2,3-d,e]quinoxalin-5-one derivatives (where R¹ = CH₃, C₂H₅; R² = CH₃, COOC₂H₅; R³ = H, CH₃, C₂H₅O, Cl, Br) is described. The physicochemical properties of these derivatives were also studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 839–841, June, 1979.     

硅胶键合N-丙基氨基磺酸催化合成8-芳基-7,8-二氢-[1,3]二氧杂环戊烯并[4,5-g]苯并吡喃-6-酮类化合物

120℃、无溶剂条件下,硅胶键合N-丙基氨基磺酸可有效催化芝麻酚、芳香醛和米氏酸三组分一锅法合成8-芳基-7,8-二氢-[1,3]二氧杂环戊烯并[4,5-g]苯并吡喃-6-酮类化合物.考察了温度及催化剂用量对产率的影响.产物的结构经1H NMR,13C NMR,质谱和元素分析进行了表征.     

8-(4-取代苯基)-10,10-二甲基-6-苯基-10 H-吡啶并[1,2-a]吲哚盐的合成

2,3,3-三甲基-3H-吲哚高氯酸盐与取代查耳酮在异戊醇中反应,得到五种新的8-(4-取代苯基)-10,10-二甲基-6-苯基-10 H-吡啶并[1,2-a]吲哚盐[R=Me_2N-(3a),R=MeO-(3b);R=Br-(3c),R=H-(3d);R=O_2N-(3e)]通过元素分析和光谱测定确证了产物的结构。紫外光谱表明,λ_(max)与R有关,其次序为Me_2N—>MeO—>Br—>H—>O_2N—     

Synthesis and Crystal Structure of 5-Cyclopropyl- 10-（4-fluorophenyl）-7,7-dimethyl-7,8-dihydro-5H- indeno[1,2-b]quinoline-9,11（6H,10H）-dione

The title compound 5-cyclopropyl-10-(4-fluorophenyl)-7,7-dimethyl-7,8-dihydro- 5H-indeno[1,2-b]quinolne-9,11(6H,10H)-dione was obtained by the reaction of 4-fluorobenzal- dehyde, 2H-indene-1,3-dione and 3-(cyclopropylamino)-5,5-dimethylcyclohex-2-enone in the presence of acetic acid under microwave irradiation. Its structure was confirmed by IR and 1H- NMR spectra. The crystal is of monoclinic, space group P21/c with a = 14.138(3), b = 8.952(2), c = 17.140(3) , β = 102.253(3)o, C27H24FNO2, Mr = 413.47, Z = 4, V = 2119.9(8) 3, Dc = 1.296 g/cm3, μ(MoKα) = 0.087 mm-1, F(000) = 872, the final R = 0.0425 and wR = 0.0905 for 2336 observed reflections (I > 2σ(I)). X-ray analysis revealed that the pyridine ring adopts a boat conformation and the six-membered ring fused with it assumes a twist boat conformation.