Two new 1,3-oxazin derivatives, C22H24N2O5 (3I) and C19H16N2O5(3II), have been synthesized via an unusual cascade reaction. The attractive aspect of this cascade reaction is that the novel construction of 1,3-oxaz...Two new 1,3-oxazin derivatives, C22H24N2O5 (3I) and C19H16N2O5(3II), have been synthesized via an unusual cascade reaction. The attractive aspect of this cascade reaction is that the novel construction of 1,3-oxazine and the direct C-N bond formation from C-C bond can be easily achieved via pyridine-mediated acylation in a one-pot operation. Both compounds have been synthesized and characterized by elemental analysis, IR, NMR spectra and X-ray single-crystal diffraction. Compound 3I crystallizes in monoclinic, space group P21/n with α = 16.282(4), b = 7.4117(18), c = 17.256(5) A, β = 103.193(9)°, V = 2027.4(9) A3, Mr = 396.43, Z = 4, Dc= 1.299 g/cm3, F(000) = 840, MoKa radiation (λ = 0.71073 A), the final R = 0.0771 and wR = 0.1582 for 3662 were observed reflections with I 〉 2σ(I). Compound 3II crystallizes in triclinic, space group Pī with α = 7.1265(9), b = 10.1071(13), c = 23.529(3) A, α = 97.463(9), β = 96.981(9), γ = 94.345(9)°, V = 1600.5(4) A3, Z = 4, Dc = 1.409 g/cm3, F(000) = 736, CuKa radiation (λ = 1.54186 A), the final R = 0.0515 and wR = 0.1241 for 4920 observed reflections with I 〉 2σ(I). The preliminary antibacterial activities of 2 and 3 against E. coli and S. aureuswere investigated. The results showed that the inhibiting effect of 3 was higher than that of 2.展开更多
Herein, we report a novel synthesis of 1,3-oxazin-6-ones from enamides with CO2 through C--H carboxylation and one-pot cyclization. This transition-metal-free and redox-neutral process features broad substrate scope, ...Herein, we report a novel synthesis of 1,3-oxazin-6-ones from enamides with CO2 through C--H carboxylation and one-pot cyclization. This transition-metal-free and redox-neutral process features broad substrate scope, good functional group tolerance and facile product derivatization. The nucleophilic attack to CO2 from the electron-rich alkene is demonstrated for this reaction.展开更多
Flavonoids exhibit a wide range of biological activities including anti-inflammatory activity, while some 1,3-benzoxazine derivatives show anti-inflammatory activity. In order to explore the novel anti-inflammatory ag...Flavonoids exhibit a wide range of biological activities including anti-inflammatory activity, while some 1,3-benzoxazine derivatives show anti-inflammatory activity. In order to explore the novel anti-inflammatory agents, based on the principles of bioisosterism and hybridization, ten novel ehromeno[8,7-e][1,3]oxazin-4-ones were syn- thesized and characterized with IR, ^1H NMR, MS and elemental analyses. The anti-inflammatory activities of the target compounds were evaluated via the croton oil-induced ear oedema test in Swiss mice. According to screened resuits, some target compounds show potent anti-inflammatory activity.展开更多
A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequen...A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent dou-ble substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.展开更多
A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been ...A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been developed from a-hydroxy andβ-carbonyl amides and various Vilsmeier salts.A wide range of heterocyclic compounds were obtained in excellent yields(up to 97%),which will provide promising candidates lor chemical biology and drug discovery.展开更多
基金supported by the National Natural Science Foundation of China(No.81071144)Natural Science Foundation of Guangdong Province(No.9451806001002961)
文摘Two new 1,3-oxazin derivatives, C22H24N2O5 (3I) and C19H16N2O5(3II), have been synthesized via an unusual cascade reaction. The attractive aspect of this cascade reaction is that the novel construction of 1,3-oxazine and the direct C-N bond formation from C-C bond can be easily achieved via pyridine-mediated acylation in a one-pot operation. Both compounds have been synthesized and characterized by elemental analysis, IR, NMR spectra and X-ray single-crystal diffraction. Compound 3I crystallizes in monoclinic, space group P21/n with α = 16.282(4), b = 7.4117(18), c = 17.256(5) A, β = 103.193(9)°, V = 2027.4(9) A3, Mr = 396.43, Z = 4, Dc= 1.299 g/cm3, F(000) = 840, MoKa radiation (λ = 0.71073 A), the final R = 0.0771 and wR = 0.1582 for 3662 were observed reflections with I 〉 2σ(I). Compound 3II crystallizes in triclinic, space group Pī with α = 7.1265(9), b = 10.1071(13), c = 23.529(3) A, α = 97.463(9), β = 96.981(9), γ = 94.345(9)°, V = 1600.5(4) A3, Z = 4, Dc = 1.409 g/cm3, F(000) = 736, CuKa radiation (λ = 1.54186 A), the final R = 0.0515 and wR = 0.1241 for 4920 observed reflections with I 〉 2σ(I). The preliminary antibacterial activities of 2 and 3 against E. coli and S. aureuswere investigated. The results showed that the inhibiting effect of 3 was higher than that of 2.
文摘Herein, we report a novel synthesis of 1,3-oxazin-6-ones from enamides with CO2 through C--H carboxylation and one-pot cyclization. This transition-metal-free and redox-neutral process features broad substrate scope, good functional group tolerance and facile product derivatization. The nucleophilic attack to CO2 from the electron-rich alkene is demonstrated for this reaction.
基金Supported by the National Natural Science Foundation of China(No.40724053)
文摘Flavonoids exhibit a wide range of biological activities including anti-inflammatory activity, while some 1,3-benzoxazine derivatives show anti-inflammatory activity. In order to explore the novel anti-inflammatory agents, based on the principles of bioisosterism and hybridization, ten novel ehromeno[8,7-e][1,3]oxazin-4-ones were syn- thesized and characterized with IR, ^1H NMR, MS and elemental analyses. The anti-inflammatory activities of the target compounds were evaluated via the croton oil-induced ear oedema test in Swiss mice. According to screened resuits, some target compounds show potent anti-inflammatory activity.
基金Project supported by the National Natural Science Foundation of China (No. 20072032).
文摘A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent dou-ble substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.
基金the National Natural Science Foundation of China(No.51373067).
文摘A straiglitforward and efficient synthetic method of 2′-(dialkylammo)-l-alkyl-4′H-spiro[indoline-3,5′-oxazole]-2,4′-diones and 2-(dialkylamino)-5,6-dihydro-4H-naphtho[2,1-e][1,3]oxazin-4-one-derivatives have been developed from a-hydroxy andβ-carbonyl amides and various Vilsmeier salts.A wide range of heterocyclic compounds were obtained in excellent yields(up to 97%),which will provide promising candidates lor chemical biology and drug discovery.