苦茶（Camellia assamica var. kucha）是一种特殊的野生茶树资源，它以1，3，7，9-四甲基尿酸（四甲基尿酸）为主要的嘌呤生物碱。用正交试验法对苦茶果皮中四甲基尿酸的提取工艺进行了研究，采用正交表k（3^4），以料液比、超声时间...苦茶（Camellia assamica var. kucha）是一种特殊的野生茶树资源，它以1，3，7，9-四甲基尿酸（四甲基尿酸）为主要的嘌呤生物碱。用正交试验法对苦茶果皮中四甲基尿酸的提取工艺进行了研究，采用正交表k（3^4），以料液比、超声时间、回流时间和提取次数为因素，以四甲基尿酸的含量为指标，采用高效液相色谱法进行检测，得到的最佳提取参数为：料液比1：12，超声提取20min后回流提取3次，每次1．5h。所得提取液用氯仿萃取后浓缩至干，经75％乙醇重结晶纯化，可得到纯度〉99％的四甲基尿酸。展开更多
Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyri...Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyridine. A plausible mechanism was hypothesized.展开更多
A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions o...A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.展开更多
Catalytic chemiluminescence of over twenty metallic ions in the systemof 2, 6, 7-tihydroxyl-9- (4'-chlorophenyl)-3-fluorone (Cl-PF )-H2O2 has been tested.Trace amount of Co(Ⅱ) strong1y catalysed this chemilumines...Catalytic chemiluminescence of over twenty metallic ions in the systemof 2, 6, 7-tihydroxyl-9- (4'-chlorophenyl)-3-fluorone (Cl-PF )-H2O2 has been tested.Trace amount of Co(Ⅱ) strong1y catalysed this chemiluminescence reaction, especiallyin presence of cationic surfactant cetyltrimethylammonium bromide (CTMAB), andthe chemiluminescence intensity was proportional to the concentraction of Co(Ⅱ) in therange 0. 5~6ng. ml-1 Co(Ⅱ). Two steps could be involved in the chemiluminescentreaction of C1-PF. In alkaline solution, the O2 radical ion should attack an oxygenbridge between the benzene rings of Cl-PF with break in oxygen bridge bond to produce reaction product which is excited by the energy derived from this chemical reaction. The electronic excited state emits the radiation(560 nm) on falling to the groundstate, followed by formation of polyphenol derivatives. the polyphenol derivatives arefurther oxidized to produce chemiluminescence (480 nm) which is due to emission fromsinglet oxygen.展开更多
Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa i...Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa is formed. The constitution is based on dates of spectrums 1Н and 13С NMR. At 95℃?- 97℃, mixtures of 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa and of 6,8-di-tert-butyl-3-(N-acetylamine)spiro(4,5)deca-1-oxa-5,8-dien-2,7-dione are produced. Structures are calculated by the method of Hartrii-Foka. Values of enthalpies and of entropies allow to assume dynamic isomerism.展开更多
文摘苦茶（Camellia assamica var. kucha）是一种特殊的野生茶树资源，它以1，3，7，9-四甲基尿酸（四甲基尿酸）为主要的嘌呤生物碱。用正交试验法对苦茶果皮中四甲基尿酸的提取工艺进行了研究，采用正交表k（3^4），以料液比、超声时间、回流时间和提取次数为因素，以四甲基尿酸的含量为指标，采用高效液相色谱法进行检测，得到的最佳提取参数为：料液比1：12，超声提取20min后回流提取3次，每次1．5h。所得提取液用氯仿萃取后浓缩至干，经75％乙醇重结晶纯化，可得到纯度〉99％的四甲基尿酸。
文摘Novel cyclic esters (1R, 2R, 3R, 5S, 7S, 9R, 12R)-3-(t-butyldimethylsilyl)oxy-7- methoxymethyloxy-2, 10-dimethyl-12-oxatricyclo [7.2.1.05,12] dodecane were prepared when their precursor 1 was treated with SOCl2/pyridine. A plausible mechanism was hypothesized.
文摘A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries.
文摘Catalytic chemiluminescence of over twenty metallic ions in the systemof 2, 6, 7-tihydroxyl-9- (4'-chlorophenyl)-3-fluorone (Cl-PF )-H2O2 has been tested.Trace amount of Co(Ⅱ) strong1y catalysed this chemiluminescence reaction, especiallyin presence of cationic surfactant cetyltrimethylammonium bromide (CTMAB), andthe chemiluminescence intensity was proportional to the concentraction of Co(Ⅱ) in therange 0. 5~6ng. ml-1 Co(Ⅱ). Two steps could be involved in the chemiluminescentreaction of C1-PF. In alkaline solution, the O2 radical ion should attack an oxygenbridge between the benzene rings of Cl-PF with break in oxygen bridge bond to produce reaction product which is excited by the energy derived from this chemical reaction. The electronic excited state emits the radiation(560 nm) on falling to the groundstate, followed by formation of polyphenol derivatives. the polyphenol derivatives arefurther oxidized to produce chemiluminescence (480 nm) which is due to emission fromsinglet oxygen.
文摘Results of oxidation 2-(N-acetylamine)-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid oxygen depend on temperature. At 55℃?- 60℃, 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa is formed. The constitution is based on dates of spectrums 1Н and 13С NMR. At 95℃?- 97℃, mixtures of 2,4-di-tert-butylbicyclo(4,3,1)deca-4,6-dien-8-(N-acetylamine)-3,9-dion-1-oxa and of 6,8-di-tert-butyl-3-(N-acetylamine)spiro(4,5)deca-1-oxa-5,8-dien-2,7-dione are produced. Structures are calculated by the method of Hartrii-Foka. Values of enthalpies and of entropies allow to assume dynamic isomerism.
