A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives（8αa ＂8αh or 8βa ＂8βh） was synthesized from the important intermediates 5 by N-acylation and acidic hydrolysis.Compounds 5α and 5β wer...A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives（8αa ＂8αh or 8βa ＂8βh） was synthesized from the important intermediates 5 by N-acylation and acidic hydrolysis.Compounds 5α and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and reduction.The structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT（distortionless enhancement by polarization transfer）,HMQC（hetero-nuclear multiple quantum coherence） and NOE（nuclear overhauser effect） correlation.展开更多
The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole der...The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole derivative 4. Treatment of 4 with 2-chlorobenzoyl chloride gave diethyl 2,6-dimethyl-3,5-diyl-（1-2（chlorobenzoyl）-1H-pyrazole-3-diethyl-carboxylate） pyridine 5. Fine crystal of 5 suitable for XRD analysis was obtained form recrystalization in ethyl acetate. The crystal belongs to the triclinic system, space group P1^-, with a = 1.0342（11）, b = 1.2211（12）, c = 1.5013（15） nm, α = 82.5190（10）,β = 85.7960（10）,γ = 85.3150（10）°, V= 1.8697（3） nm^3, Dc= 1.173 g/cm^3, μ = 0.219 mm^-1, F（000） = 684, Z = 2, the final R = 0.0720 and wR = 0.2211.展开更多
The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-a...The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-acyl to N-acyl product depends upon the acylation reagents. O-acyl derivatives can be converted to the N-acyl compounds by isomerization under acidic conditions or heating.展开更多
Acylation of 5-methyl-3-hydroxyisoxazole (1) with 3-substituted cyclopropanecarboxylic chlorides (3) in the presence of triethylamine (TEA) in acetonitrile yields predominantly O-acylated products (4).The N-acyl isom... Acylation of 5-methyl-3-hydroxyisoxazole (1) with 3-substituted cyclopropanecarboxylic chlorides (3) in the presence of triethylamine (TEA) in acetonitrile yields predominantly O-acylated products (4).The N-acyl isomers (5) are afforded regiospecifically using trimethylsilyl ether of 3-hydroxyisoxazole (2).展开更多
基金Project supported by the National Natural Science Foundation of China(No.31701679)the Young Talent Fund of Association for Science and Technology in Shaanxi(No.20220609)+6 种基金the Open Sharing Platform for Scientific and Technological Resources of Shaanxi Province(No.2021PT-004)the Yan’an Science and Technology Planning Project(No.2022SLSFGG-005)the Young Talent Fund of Association for Science and Technology in Yanan(No.8)the Yan’an University Training Program of Innovation and Entrepreneurship for Undergraduates(No.D2021032)the Yan’an University Industry-University-Research Co-operative Cultivation Project(No.CXY202102)the Youth Innovation Team Project of Shaanxi Provincial Education Department(No.23JP193)the Youth Innovation Team of Shaanxi Universities。
基金Supported by the National Natural Science Foundation of China(No.20576094)
文摘A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives（8αa ＂8αh or 8βa ＂8βh） was synthesized from the important intermediates 5 by N-acylation and acidic hydrolysis.Compounds 5α and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and reduction.The structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT（distortionless enhancement by polarization transfer）,HMQC（hetero-nuclear multiple quantum coherence） and NOE（nuclear overhauser effect） correlation.
基金the Key Subject of Shanghai Municipal Education Commission(J50102)the Foundation of Education Commission of Shanghai Municipality(08zz44)
文摘The reaction of hydrazine hydrate with a new α,γ-diketone ester 3, derived from the reaction of 2,6-dimethyl-3,5-diacetyl-pyridine 2 with diethyl oxalate in the presence of sodium ethoxide, afforded the pyrazole derivative 4. Treatment of 4 with 2-chlorobenzoyl chloride gave diethyl 2,6-dimethyl-3,5-diyl-（1-2（chlorobenzoyl）-1H-pyrazole-3-diethyl-carboxylate） pyridine 5. Fine crystal of 5 suitable for XRD analysis was obtained form recrystalization in ethyl acetate. The crystal belongs to the triclinic system, space group P1^-, with a = 1.0342（11）, b = 1.2211（12）, c = 1.5013（15） nm, α = 82.5190（10）,β = 85.7960（10）,γ = 85.3150（10）°, V= 1.8697（3） nm^3, Dc= 1.173 g/cm^3, μ = 0.219 mm^-1, F（000） = 684, Z = 2, the final R = 0.0720 and wR = 0.2211.
基金Supposed by the National Natural Science Foundation of China
文摘The reactions of 5-methyl-3-hydroxyisoxazole with 2, 2-dimethyl, 3-substituted cyclopropanecarboxylic chlorides give O-acyl-5-methyl-3-hydroxyisoxazole and N-acyl-5-methylisoxazolin-3-one derivatives. The ratio of O-acyl to N-acyl product depends upon the acylation reagents. O-acyl derivatives can be converted to the N-acyl compounds by isomerization under acidic conditions or heating.
文摘 Acylation of 5-methyl-3-hydroxyisoxazole (1) with 3-substituted cyclopropanecarboxylic chlorides (3) in the presence of triethylamine (TEA) in acetonitrile yields predominantly O-acylated products (4).The N-acyl isomers (5) are afforded regiospecifically using trimethylsilyl ether of 3-hydroxyisoxazole (2).
