The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in tric...The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in triclinic, space group P1 with a = 5.756(1), b = 10.099(1), c = 17.106(3) ? a = 80.49(1), b = 83.13(1), g = 80.07(1), V = 961.8(2) ?, Dc = 1.374 g/cm3, = 0.231 mm-1, Z = 2, F(000) = 412, the final R = 0.0369 and wR = 0.0947. In the molecule the pyran ring is of boat conformation. The intermolecular hydrogen bonds of NH…O(5)(x+2, y+1, z+1) and NH…Cl (x+1, y1, z) as well as intramolecular hydrogen bond NH…O(5) are found.展开更多
Task specific onium salt has been presented as soluble support in the synthesis of benzopyrans in this paper. This method allows for results by far superior to those reported other soluble supports and allows for very...Task specific onium salt has been presented as soluble support in the synthesis of benzopyrans in this paper. This method allows for results by far superior to those reported other soluble supports and allows for very easy purifications of reaction products.展开更多
Two new benzopyran derivatives,1-[（rel 2S,3R）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（1）,and 1-[（rel 25,35）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（2）,along with four known flavonoi...Two new benzopyran derivatives,1-[（rel 2S,3R）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（1）,and 1-[（rel 25,35）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（2）,along with four known flavonoids,prodelphinidin C,prodelphinidin B3,（-）-epi-gallocatechin and（＋）-gallocatechin,were isolated from the stems of Gouania leptostachya DC.var. tonkinensis Pitard.Their structures were determined on the basis of spectroscopic methods including HR-ESI-MS,1D and 2D NMR.Prodelphinidin C exhibited significant inhibitory activity forα-glucosidase.展开更多
Under microwave irradiation,2,2＇-alkoxy-bridging or 4,4＇-alkoxy-bridging dibenzaldehydes reacted with 4-hydroxycoumarin in DMF to give a series of 3,3＇,3″,3＇″-o-and 3,3＇,3″,3＇″-p-phenylenedimethylidinetetrak...Under microwave irradiation,2,2＇-alkoxy-bridging or 4,4＇-alkoxy-bridging dibenzaldehydes reacted with 4-hydroxycoumarin in DMF to give a series of 3,3＇,3″,3＇″-o-and 3,3＇,3″,3＇″-p-phenylenedimethylidinetetrakis-（4-hydroxy-2H-1-benzopyran-2-ones） in moderate yields.The structures of the synthetic coumarin derivatives were characterized with IR,1H NMR and MS spectroscopy as well as X-ray single crystallography.展开更多
[Objectives]Based on spectrophotometry,a method for determining the total flavonoid content in milk powder was established by optimizing sample pretreatment conditions,and method validation was performed.[Methods]Tota...[Objectives]Based on spectrophotometry,a method for determining the total flavonoid content in milk powder was established by optimizing sample pretreatment conditions,and method validation was performed.[Methods]Total flavonoids in milk powder were extracted with ethanol using 45℃ water bath ultrasonication for 60 min.Flavonoids contain a benzopyran ring structure and react with aluminum nitrate in a potassium acetate environment to form a yellow complex.The absorbance of this complex was measured at 420 nm for quantitative determination.[Results]The method exhibited a good linear relationship within the range of 0.2-1.0 mg.The limit of detection(LOD)was 0.05 g/100 g,and the limit of quantification(LOQ)was 0.3 g/100 g.When the spiked amount of total flavonoids was in the range of 0.3% to 1.0%,the spike recovery rates were 99.3% to 103.4%,and the relative standard deviations(RSD s)were less than 3.0%.[Conclusions]This method offers advantages such as rapidness,accuracy,good stability,and high sensitivity,and can be used for the detection of total flavonoid content in milk powder.展开更多
The syntheses of 4H-benzopyran derivatives were investigated using dialdehyde as a key starting material. The reaction proceeds under microwave irradiation in good yield (87%—95%) with short reaction time (5—8 min),...The syntheses of 4H-benzopyran derivatives were investigated using dialdehyde as a key starting material. The reaction proceeds under microwave irradiation in good yield (87%—95%) with short reaction time (5—8 min), therefore providing a rapid and efficient method of synthesizing a variety of compounds containing two 4H-benzopyran units.展开更多
The synthesis of 2-phenylimino-4H-chromene-3-carbonitriles 6(a-d) in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocy...The synthesis of 2-phenylimino-4H-chromene-3-carbonitriles 6(a-d) in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocyclization between 2-hydroxybenzaldehyde 1 and propanedinitrile 2 which produced 2-iminocoumarin 3 which was submitted to nitrogen/nitrogen displacement in the presence of aromatic primary amine 4. In the third step, reduction of 5 led to the desired 2-phenylimino-4H-chromene-3-carbonitriles 6. Compounds 5(a-d) and 6(a-d) were evaluated for their potential in vitro cytotoxicity against six selected tumor cell lines (Huh7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and tested for their protein kinase inhibition on eight selected protein kinases. Among them, compounds 5c and 6b exhibited inhibition on HsCK1e (5c: 44% and 6b: 42% at 1 μM) and 5c for cytotoxicity on PC3 cell lines (63% at 25 μM).展开更多
基金Supported by NNSFC (No. 20372057) NSF of Jiangsu Province (No. BK2001142) Jiangsu Education Department (No. 01KJB150008) and the Key Lab of Biotechnology for Medicinal Plants of Jiangsu Province (02AXL 14)
文摘The title compound 2-amino-3-ethoxycarbonyl-4-(4-chlorophenyl)-4H,5H-pyrano- [3,2-c]-benzopyran-5-one (C21H16ClNO5, Mr = 397.80) has been synthesized and characterized by X-ray crystallography. It crystallizes in triclinic, space group P1 with a = 5.756(1), b = 10.099(1), c = 17.106(3) ? a = 80.49(1), b = 83.13(1), g = 80.07(1), V = 961.8(2) ?, Dc = 1.374 g/cm3, = 0.231 mm-1, Z = 2, F(000) = 412, the final R = 0.0369 and wR = 0.0947. In the molecule the pyran ring is of boat conformation. The intermolecular hydrogen bonds of NH…O(5)(x+2, y+1, z+1) and NH…Cl (x+1, y1, z) as well as intramolecular hydrogen bond NH…O(5) are found.
基金Supported by the National Natural Sciences Foundation of China(No.20772026)the 2007 Excellent Mid-youth Innovative Team Project of the Education Department of Hubei Province, China(No.T200701)
文摘Task specific onium salt has been presented as soluble support in the synthesis of benzopyrans in this paper. This method allows for results by far superior to those reported other soluble supports and allows for very easy purifications of reaction products.
基金the National Science & Technology Major Project "Key New Drug Creation and Manufacturing Program",China(No.2009ZX09301-001)
文摘Two new benzopyran derivatives,1-[（rel 2S,3R）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（1）,and 1-[（rel 25,35）-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone（2）,along with four known flavonoids,prodelphinidin C,prodelphinidin B3,（-）-epi-gallocatechin and（＋）-gallocatechin,were isolated from the stems of Gouania leptostachya DC.var. tonkinensis Pitard.Their structures were determined on the basis of spectroscopic methods including HR-ESI-MS,1D and 2D NMR.Prodelphinidin C exhibited significant inhibitory activity forα-glucosidase.
基金Supported by the National Natural Science Foundation of China(No.20672091)
文摘Under microwave irradiation,2,2＇-alkoxy-bridging or 4,4＇-alkoxy-bridging dibenzaldehydes reacted with 4-hydroxycoumarin in DMF to give a series of 3,3＇,3″,3＇″-o-and 3,3＇,3″,3＇″-p-phenylenedimethylidinetetrakis-（4-hydroxy-2H-1-benzopyran-2-ones） in moderate yields.The structures of the synthetic coumarin derivatives were characterized with IR,1H NMR and MS spectroscopy as well as X-ray single crystallography.
基金Supported by Key Research and Development and Achievement Transformation Plan Project of Inner Mongolia Autonomous Region(2023YFHH0093).
文摘[Objectives]Based on spectrophotometry,a method for determining the total flavonoid content in milk powder was established by optimizing sample pretreatment conditions,and method validation was performed.[Methods]Total flavonoids in milk powder were extracted with ethanol using 45℃ water bath ultrasonication for 60 min.Flavonoids contain a benzopyran ring structure and react with aluminum nitrate in a potassium acetate environment to form a yellow complex.The absorbance of this complex was measured at 420 nm for quantitative determination.[Results]The method exhibited a good linear relationship within the range of 0.2-1.0 mg.The limit of detection(LOD)was 0.05 g/100 g,and the limit of quantification(LOQ)was 0.3 g/100 g.When the spiked amount of total flavonoids was in the range of 0.3% to 1.0%,the spike recovery rates were 99.3% to 103.4%,and the relative standard deviations(RSD s)were less than 3.0%.[Conclusions]This method offers advantages such as rapidness,accuracy,good stability,and high sensitivity,and can be used for the detection of total flavonoid content in milk powder.
基金Project supported by the Natural Science Foundation of China (No. 20372057) the Natural Science Foundation of Jiangsu Province (No. BK2001142) and the Natural Science Foundation of Jiangsu Education Department (No. 01KJB150008) the key Laboratory of
文摘The syntheses of 4H-benzopyran derivatives were investigated using dialdehyde as a key starting material. The reaction proceeds under microwave irradiation in good yield (87%—95%) with short reaction time (5—8 min), therefore providing a rapid and efficient method of synthesizing a variety of compounds containing two 4H-benzopyran units.
文摘The synthesis of 2-phenylimino-4H-chromene-3-carbonitriles 6(a-d) in good overall yields using an efficient and practical methodology in 3 steps has been implemented in this present work. The first step was a heterocyclization between 2-hydroxybenzaldehyde 1 and propanedinitrile 2 which produced 2-iminocoumarin 3 which was submitted to nitrogen/nitrogen displacement in the presence of aromatic primary amine 4. In the third step, reduction of 5 led to the desired 2-phenylimino-4H-chromene-3-carbonitriles 6. Compounds 5(a-d) and 6(a-d) were evaluated for their potential in vitro cytotoxicity against six selected tumor cell lines (Huh7-D12, Caco2, MDA-MB231, HCT 116, PC3 and NCI-H727) and tested for their protein kinase inhibition on eight selected protein kinases. Among them, compounds 5c and 6b exhibited inhibition on HsCK1e (5c: 44% and 6b: 42% at 1 μM) and 5c for cytotoxicity on PC3 cell lines (63% at 25 μM).
