975 resultados para Aryl Hydrocarbon Hydroxylases


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本文对禄春安息香(Styrax macranthus)种子和攀援孔药花(Porandra scandens)全草的化学成分进行了研究,共获得30个化合物,其中2个为新化合物。 从禄春安息香种子95%乙醇提取物中分离并鉴定了12个化合物,其中2个新化合物鉴定为3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl] propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzofuran-5-yl] propanoate (1) 和去甲氧基-egonol-龙胆双糖甙 (2);已知化合物分别为2-(3,4-二氧亚甲基苯基)-5-甲酰基-7-甲氧基-苯并呋喃 (3)、egonol (4)、去甲氧基-egonol (5)、去甲基-egonol (6)、egonol-葡萄糖甙 (7)、egonol-龙胆双糖甙 (8)、egonol-龙胆三糖甙 (9)、豆甾醇 (10)、二十四烷酸 1-甘油酯 (11) 和胡萝卜甙 (12)。生物活性测试发现,化合物2具有促进雌激素E2合成的作用。 从攀援孔药花全草95%乙醇提取物中分离并鉴定了19个化合物:(2S,3S,4R)-2-[(2R)-2-羟基-二十一烷酰基氨基]-二十一烷-1,3,4-三醇 (13)、(2S,3S,4R)–2–二十四烷酰基氨基-十八烷-1,3,4-三醇 (14)、胡萝卜甙 (12)、β-谷甾醇 (15)、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇 (16)、6β-羟基-豆甾-4-烯-3-酮 (17)、十六烷酸 1-甘油酯 (18)、桦木酸 (19)、大黄素 (20)、二十二烷酸 1-甘油酯 (21)、对羟基苯甲醛 (22)、十七烷酸 1-甘油酯 (23)、金色酰胺醇乙酸酯(24)、十九烷酸 1-甘油酯 (25)、棕榈酸 (26)、(E)-p-香豆酸 (27)、(22E,24S)-24-麦角甾醇-7,22-二烯-3β,5α,6β-三醇 (28)、2-去氧-β-蜕皮激素 (29)和auranamide (30)。 综述了近十年来发现的2-芳基苯并呋喃类新木脂素的结构特征、来源、生物活性和化学全合成。 Phytochemical investigation on the seeds of Styrax macranthus and the whole plants of Porandra scandens led to the isolation of thirty compounds, two of which were new ones. Two new 2-aryl benzofuran derivatives, 3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl]propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzo furan-5-yl]propanoate (1) and demethoxy egonol gentiobioside (2), were isolated from the 95% aqueous ethanolic extract of the seeds of Styrax macranthus, together with 7-methoxy-2-(3,4-methylenedioxyphenyl) benzofuran-5-carbaldehyde (3), egonol (4), demethoxy egonol (5), demethyl egonol (6), egonol glucoside (7), egonol gentiobioside (8), egonol gentiotrioside (9), stigmasterol (10), 2,3-dihydroxypropyl tetracosoate (11), and daucosterol (12). In vitro test, compound 2 promote the synthesis of estrogen E2. Nineteen compounds were isolated from the 95% aqueous ethanolic extract of the whole plant of Porandra scandens for the first time. Their structures were identified as (2S,3S,4R)-2-[(2R)-2-hydroxy-heneicosanoylamino]-1,3,4- heneicosanetriol (13), (2S,3S,4R)-2-tetracosanoylamino-1,3,4-octadecanetriol (14), daucosterol (15), β-sitosterol (12), (20S,22E,24R)-5α,8α-epidioxy-ergosta-6,22-diene- 3β-ol (16), 6β-hydroxylstigmast-4-en-3-one (17), 1-glycerol-1-hexadecoate (18), betulinic acid (19), emodin (20), 1-glycerol-1-docosoate (21), p-hydroxybenzaldehyde (22), 1-glycerol-1-heptadecoate (23), aurantiamide acetate (24), 1-glycerol-1- nonadecoate (25), palmatic acid (26), (E)-p-coumaric acid (27), (22E,24S)- 24-metbylcbolesta-7,22-diene-3β,5α,6β-triol (28), 2-deoxycrustecdysone (29), and auranamide (30). The characteristic, natural resource, bioactivity, and the total synthesis of 2-aryl benzofurans were reviewed.

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1-甲基-2-甲氧羰基-3, 6, 8-三羟基-7-甲氧基蒽醌是从唐菖蒲干球茎中分离到的具有环氧化酶-2选择性抑制活性的多取代蒽醌类化合物。本文试图合成该化合物,实现了其类似物的合成,同时发现了几个未见报道的反应。 1.通过Diels-Alder 反应合成了关键中间体——3-甲基-5-羟基-1, 2, 4-苯三甲酸三甲酯,1-COOMe选择性水解产物与1, 2, 3-三甲氧基苯进行分子间Friedel-Crafts反应的产物再进行分子内Friedel-Crafts反应得到了目标产物的类似物1-甲基-2-甲氧羰基-3-羟基-6,7,8-三甲氧基蒽醌(路线1)。目标产物及其它类似物的合成正在进行中。 2.以乙酰乙酸甲酯和巴豆醛为原料,经过Michael加成、分子内的Aldol反应、芳香化、选择性甲酰化和还原反应,得到关键中间体2-甲基-3-羟甲基-6-甲氧基苯甲酸甲酯及其衍生物。通过该化合物与3,4,5-三甲氧基苯甲酸甲酯进行Friedel-Crafts烷基化反应得到了多取代的二苯基甲烷衍生物,拟进一步关环合成目标化合物(路线2)。 3.发现邻甲氧基苯甲酸甲酯中酯甲基可以被正丁基锂和仲丁基锂中烷基交换生成相应的酯,反应的机理不明确。当使用叔丁基锂时,得到的是邻甲氧基苯基叔丁酮,这个方法可以用来合成芳基叔丁酮类化合物。 4.以2-苄氧基-6-甲基苯甲酸甲酯为原料进行氯甲基化反应时,以苯和二氯乙烷作溶剂,发生了苄基的迁移和芳环的偶联,分别得到2,2'-二甲基-3,3'-二甲氧羰基-4,4'-二羟基联苯和2,2'-二甲基-3,3'-二甲氧羰基-4,4'-二羟基-5,5'-二苄基联苯。这是对称联苯合成的新方法。 5.水杨酸羟基邻对位的选择性甲酰化可以分别通过水杨酸和水杨酸甲酯用HMTA/CF3COOH来实现。 6.Lewis酸催化3,4,5-三甲氧基苄醇环化成1, 2, 3, 6, 7, 8, 11, 12, 13-nonamethoxyl-10,15-dihydro-5H-trbibenzo [a, d, g] cyclononene (NDTC),产率(54%)高于已有方法(12%)。 Methyl 3,6,8-trihydroxy-7-methoxy-1-methylanthraquinone-2-carboxylate is a new COX-2 selective inhibitor isolated from Gladiolus gandavensis. Two strategies were investigated to synthesis this compound, in which some important reactions were discovered. 1. The key intermediate 5-hydroxy-3-methylbenzene-1,2,4-tricarboxylic acid 2,4-dimethyl ester was prepared via Diels-Alder reaction followed by selective hydrolysis of 1-COOMe. This compound was coupled with 1,2,3-trimethoxybenzene and the product undergo intramolecular Friedel-Crafts reaction to give methyl 3-hydroxy-5,6,7-trimethoxy-1-methylanthraquinone-2-carboxylate (1st route). The target compound and other analogues are being prepared with the same procedure. 2. The key intermediates methyl 3-hydroxymethyl-6-methoxy-2-methylbenzoate and its derivatives were prepared starting from crotonaldehyde and methyl acetoacetate via Michael addition, intramolecular aldol reaction, aromatization, formylation and reduction. The intermediates were coupled respectively with derivatives of gallic acid to give polysubstituted diphenylmethane. However, attempts to cyclize these compounds to the target compounds and analogues were not successful (2nd route). 3. In the process for ortho-lithiation of methyl 2-methoxybenzoate, the substrate converted respectively to n-butyl 2-methoxybenzoate and sec-butyl 2-methoxybenzoate when n-BuLi and sec-BuLi were used. However, tert-BuLi reacted with methyl 2-methoxybenzoate afford 2-methoxyphenyl tert-butyl ketone, which could be used to synthesize aryl tert-butyl ketones. 4. The transformtion of methyl 2-benzoxy-6-methylbenzoate to dimethyl 4,4'-dihydroxy-2,2'-dimethylbiphenyl-3,3'-dicarboxylate in benzene, and dimethyl 5,5'-dibenzyl-4,4'-dihydroxy-2,2'-dimethylbiphenyl-3,3'-dicarboxylate in 1,2-dichloroethane in the presence of ZnCl2 provides a new method for the synthesis of symmetric biphenyl. 5. The formylation of salicylic acid at C-5 and methyl 2-hydroxybenzoate at C-3 could be regioselectively realized by using HMTA/CF3COOH. 6. Racemic 1, 2, 3, 6, 7, 8, 11, 12, 13-nonamethoxyl-10, 15-dihydro-5H-trbibenzo [a, d, g] cyclononene was prepared via Lewis acids catalyzed trimerization of 3, 4, 5-trimethoxylbenzyl alcohol with yield (54%) higher than the reported procesure (12%).

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手性胺是合成天然产物和手性药物的重要中间体,亚胺的不对称催化还原是制备光学活性手性胺的最直接有效的方法之一。但是,由于C=N双键的反应活性较弱以及容易发生E/Z异构等问题,亚胺的不对称催化还原具有很大的挑战性,既具有高对映选择性又具有宽广底物普适性的催化剂很少。 本文分别由手性脯氨酸、哌啶酸、哌嗪酸以及氨基醇出发,设计和合成了一系列结构新颖、合成简便、性能优良的酰胺类有机小分子路易斯碱催化剂,以廉价的三氯氢硅为氢源,用这些催化剂催化亚胺不对称还原,得到了非常优良的收率、对映选择性和前所未有的底物普适性。 文献研究认为,除N-甲酰基外,分子内含有芳香酰胺是能催化亚胺还原的有机小分子路易斯碱催化剂具有较高对映选择性的必要条件,我们研究发现N-甲酰脯氨酸非芳香酰胺类催化剂(包括结构简单的C2-对称型脯氨酰胺类催化剂),对N-芳基酮亚胺的还原可获得达86%的对映选择性,远高于同类芳香酰胺催化剂,证明N-甲酰非芳香酰胺类路易斯碱催化剂在亚胺还原中也能得到高的对映选择性。 在进一步研究中,我们以手性六元哌啶酸为模板,分别设计合成了N-甲酰哌啶酸芳香酰胺和N-甲酰哌啶酸非芳香酰胺两类催化剂,其中芳香酰胺催化剂(S)-N-(甲酰基)哌啶-2-酸-1-萘基酰胺(28)和非芳香酰胺催化剂(2S,1'S,2'S)-N-(甲酰基)-哌啶-2-酸(1',2'-二苯基-2'-乙酰氧基-乙基)酰胺(30)显示出非常优良的催化活性和对映选择性,对于N-芳基芳香酮亚胺的还原,无论是缺电子体系还是富电子体系,绝大部分都能得到很高的收率(达98%)和对映选择性(达96% ee)。特别值得一提的是30对一些脂肪族亚胺和α,β-不饱和亚胺的还原,虽然底物为E/Z混合物,也能得到很高的收率(达93%)和对映选择性(达95% ee),这样的底物普适性在过渡金属催化体系中也是前所未有的。 现有的催化亚胺还原的高对映选择性催化体系大多仅适用于甲基酮亚胺底物,对位阻较大的非甲基酮亚胺很难获得好的结果。我们以L-哌嗪酸为模板设计和合成出的(S)-N-(甲酰基)-哌嗪-2-酸-4-对叔丁基苯磺酰基-苯基酰胺不但对N-芳基甲基酮亚胺有很好的对映选择性(达90% ee),而且对于大位阻的N-芳基非甲基酮亚胺有更好的对映选择性(达97% ee)。该催化剂与30在底物普适性方面具有很好的互补性。 我们还设计了基于1,2-二苯基氨基醇为模板的新型N-甲酰路易斯碱有机小分子催化剂,首次发现结构简单的N-甲酰(1S,2R)二苯基氨基醇能较好的催化N-芳基酮亚胺,最高可以得到82%的对映选择性。 针对我们设计合成的结构新颖、性能优良的催化剂,我们对催化机理进行了探讨和解释,提出了几个假想的机理模型。 Catalytic enantioselective reduction of imines represents one of the most straightforward and efficient methods for the preparation of chiral amines, an important intermediate for the synthesis of natural products and chiral drugs. However, asymmetric reduction of imines remains a big challenge and highly enantioselective catalysts with a satisfactorily broad substrate scope remain elusive. Factors contributing to the difficulty of this transformation include the weak reactivity of the C=N bond and the existence of inseparable mixtures of E/Z isomers. Starting from chiral proline, pipecolinic acid, piperazine-2-carboxylic acid and 1,2-diphenyl amino alcohol, a series of structurally simple and easily prepared amides were developed as highly effective Lewis basic organocatalysts for the asymmetric reduction of imines with trichlorosilane as the reducing agent, which promoted the reduction of N-aryl imines with high yields and excellent enantioselectivities with an unprecedented substrate spectrum. In the literature, it has been believed that besides the N-formyl group, the existence of an arylamido group in the structure of Lewis basic organocatalysts is a prerequisite for obtaining high enantioselectivity in the catalytic reduction of imines. However, we found that the N-formyl-L-prolinamides bearing non-arylamido groups, including structurally simple C2-symmetric tetraamides, could also work as effective Lewis basic catalysts to promote the asymmetric reduction of ketimines with high enantioselectivities (up to 86% ee), which are even more enantioselective than the analogues with arylamido groups. In further studies, we developed novel N-formamides with arylamido groups and non-arylmido groups as Lewis basic catalysts using the commercially available L-pipecolinic acid as the template. The catalysts (S)-1-formyl-piperidine-2-carboxylic acid naphthylamide 28 and (2S,1'S,2'S)-acetic acid 2-[(1-formyl-piperidine-2-carbonyl) -amino]-1,2-diphenyl-ethyl ester 30 were found to promote the reduction of a broad range of N-aryl imines in high yields (up to 98%) and excellent ee values (up to 96%) under mild conditions. Furthermore, catalyst 30 also exhibited high enantioselectivities (up to 95% ee) for the challenging aliphatic ketimines and α,β-unsaturated imines despite that these imines exist as E/Z isomeric mixtures. The broad substrate spectrum of this catalyst is unprecedented in catalytic asymmetric imine reduction, including transition-metal-catalyzed hydrogenation processes. Many of the currently available highly enantioselective catalytic systems only tolerate methyl ketimines, which gave poor results for bulkier non-methyl ketimines. Starting from L-piperazine-2-carboxylic acid, we developed (S)-4-(4-tert- butylbenzenesulfonyl)-1-formyl-N-phenyl-piperazine-2-carboxamide as highly enantioselective Lewis basic catalysts for the hydrosilylation of both methyl ketimines and steric bulky non-methyl ketimines. Moreover, higher enantioselectivities were obtained for non-methyl ketimines than methyl ketimines under the catalysis of this catalyst. Thus, this catalyst system complements with 30 in terms of the substrate scope. We also found that easily accessible (1R,2S)-N-formyl-1,2-diphenyl- 2-aminoethanol worked as an effective Lewis basic catalyst in the enantioselective hydrosilylation of ketimines, affording high enantioselectivities (up to 82% ee) for a broad range of ketimines. To rationalize the high efficiencies of the structurally novel catalysts we developed, several catalytic models have been proposed.

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氮杂环化合物大多数都是具有生理活性的物质,例如喹喔啉化合物与苯二氮卓类化合物,因此研究氮杂环化合物骨架的构建方法具有一定意义。绿色化学的迅速发展迫切要求化学家发展清洁、经济和环境较友好条件下的有机合成方法。其中,水相反应与绿色固体酸催化剂的使用都是实现绿色有机合成的重要途径,它们非常具有潜力,近些年受到了广泛关注。本论文的主要工作是围绕水相及固体酸催化条件下两类具有生物活性的含氮杂环小分子的合成方法而开展的,具体包括以下内容: 1. 研究和探索出了两类绿色固体酸催化剂蒙脱土(Mont. K-10)和杂多酸(H4SiW12O40), 在水相条件下成功合成出喹喔啉化合物的有效方法。两个催化体系都以无毒无公害的水作反应溶剂,实验条件温和,操作安全简便,反应速度快,底物普适性强,产率高,且产物易分离收集。两类固体酸催化剂,对设备腐蚀性小,可回收循环使用,对环境无公害; 蒙脱土催化大部分底物能得到当量产率的产物,硅钨酸催化催化剂负载量小。 2. 实现了无溶剂条件下,以杂多酸(H3PW12O40)作催化剂,高效合成1,5-苯二氮卓衍生物的合成方法。该催化体系具有以下一些优势:实验条件温和,反应速度较快,底物普适性良好,产物易分离收集,反应过程中没有加入其它有机溶剂,绿色环保。 ‘Green Chemistry’ is currently a major issue of modern chemistry. It is widely acknowledged that there is a growing need for more environmentally acceptable processes in the chemical industry. New green catalysts and green reaction media are the important and efficient strategies in green chemistry. New green catalysts include solid acid catalysts, solid base catalysts, metal catalysts not only possess higher activity and selectivity, but also are easily separated from reaction system. Green reaction media include water, supercritical fluids and ionic liquids can not only substitute traditional toxic and harmed organic solvents, but also improve reaction activity and selectivity. Meanwhile water is a promising green reaction medium for use in modern chemistry because it has a number of advantages such as the cheapest solvent available on earth, being non-hazardous and non-toxic to the environment. Solid acids had also attracted much attention for realizing green chemistry due to their unique acidity, high activity and efficiency as organic catalysts. Nitrogen-containing heterocyclic compounds of different ring sizes such as quinoxaline and benzodiazepine are the important pharmacologically active compounds. Due to the wide biological significance of these compounds, the synthesis of these types of compounds have received a great deal of attention. Despite the large availability of methods to construct nitrogen-containing heterocyclic compounds, there is still a strong need to further explore green methods to efficiently and safely synthesize these compounds. Thus, we aim at developing efficient and green methodology for the synthesis of quinoxaline and benzodiazepine carried out under water condition with solid acid catalysts. The contents of this dissertation are listed as the following: 1. We have developed two catalytic systems for the synthesis quinoxaline via the condensation of an aryl 1,2-diamine with a 1,2-diketone compound in the presence of Mont. K-10 or H4SiW12O40 as a catalyst in water solvent. Both of these two methods can be applied to wide range of substrates, tolerating aryl 1,2-diamine/1,2-diketone with the electron donating/drawing substituent. Operational simplicity, the ambient conditions, use of an economically convenient catalyst, use of water as a desirable solvent, high yields and short reaction times are the key features of these two protocols. 2. We developed a convenient and efficient protocol for the synthesis of a variety of 1,5-benzodiazepines in high yields via condensation of aryl o-phenylenediamine derivatives with a variety of ketones using H3PW12O40 as a green recyclable and heterogeneous catalyst under solvent-free condition. The simple experiment procedure combined with ease of recovery and reuse of this catalyst make this procedure quite simple, more convenient and environmentally benign.

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Mannich反应是有机化学中最重要的碳-碳键形成反应,其产物是合成手性胺的通用中间体。间接Mannich反应使用不稳定的预制烯醇等当体,以未修饰的酮为给体的直接方法将增强Mannich反应的效率。针对低活性苯乙酮、氨甲酸酯参与的直接Mannich反应,研究工作将更具挑战性。 在前期实验中,我们发现Lewis酸-NbCl5可高效催化苯乙酮、芳香醛、芳香胺三组分直接Mannich反应,反应在环境温度下进行,高收率获得Mannich碱。这是以苯乙酮参与的Mannich反应中,实现催化量Lewis酸催化的首次报道。该方法高效且操作简单。但就底物而言,对易去保护、低活性的氨甲酸酯类底物收率较低。我们设想Brønst酸可解决此类底物问题。令人高兴的是,杂多酸可高效催化芳香酮、芳香醛、氨甲酸酯三组分直接Mannich反应,反应在环境温度下进行,高收率获得N-保护的β-氨基酮。该方法底物范围广泛,普适性强且催化剂便宜。 基于杂多酸在苯乙酮、氨甲酸酯为底物直接Mannich反应中的高效性,我们设想杂多酸与功能化的手性有机小分子-手性伯胺组装可解决催化剂回收问题,同时实现不对称催化。实验结果表明,非共价键固载手性伯胺不能有效催化苯乙酮为底物的直接Mannich反应,无论是对映选择性还是收率均较低。随后,我们以丙二酸酯及α-氨基砜为底物,以增强底物活性,同时绕开亚胺的不稳定性。辛可宁伯胺以氢键双活化底物,有效催化原位产生氨甲酸酯类亚胺与丙二酸酯的Mannich反应,高收率获得Mannich碱,ee值中等。 我们采用逐步解决问题的策略解决Mannich反应中的部分问题并在Lewis酸催化、Brønst酸催化、非共价键固载手性伯胺催化及手性伯胺氢键催化的直接Mannich反应中做出了有益探索。 The Mannich reactions are among the most fundamental carbon-carbon bond forming reactions in organic chemistry, and the reaction products are versatile intermediates in the synthesis of chiral amines. The indirect Mannich reaction uses preformed enolate equivalents. However the preformed enolates are unstable. Thus, a direct methodology based on unmodified ketone donors would enhance the efficiency of the Mannich reaction. Especially researches for the directed Mannich reactions of acetophenone, carbamate, which own lower activities, will be more challengeable. In the initial experiments, we found an efficient Lewis acid-NbCl5 which could catalyze three-component Mannich-type reaction of acetophenone, aromatic aldehydes and aromatic amines at ambient temperature in high yields. This is the first report that use catalytic amount of Lewis acid in the Mannich reactions of .acetophenone. The method reported is not only simple to operate but also efficient. However, as far as amines are concerned, the substrates of carbamates which can be deprotected more easily and less reactive than amines give low yields. We envisaged that Brønsted acid would resolve this problem. Pleasingly, heteropoly acids (HPA) efficiently catalyzed one-pot three-component Mannich reactions of aryl aldehydes, aryl ketones, and carbamates at ambient temperature and afforded the corresponding N-protected β-amino ketones in good to excellent yields. This method provides a novel and improved modification of three-component Mannich reactions in terms of a wide scope of aldehydes, ketones and carbamates, economic viability. Based on the high efficiency of heteropoly acids in the Mannich reaction of acetophenone and carbamates, we envisaged that if HPA were combined with functionalized chiral organocatalysts–chiral primary amines the assemblies may be able to act as recoverable asymmetric organocatalysts. The results of exprimentals showed that noncovalently supported heterogeneous chiral primary amine couldn’t effectively catalyze the Mannich reactions which own two the substrate of acetophenone regardless of enantioselectivity and yield. Then, we employed malonates and α-amido sulfones as substrates to enhance reactivity of substrates and circumvent the instability of imines. A moderately enantioselective and highly yield Mannich reaction with in situ generation of carbamate-protected imines from stable α-amido sulfones catalyzed by cinchonine primary amine catalyst was developed. It is noteworthy that cinchonine primary amine can dual activate substrates through H-bond activation and thus promote the reaction. We applied step-by-step-strategy to resolve some problems in the Mannich reactions and did some instructive explorations in Lewis acid catalysis, Brønst acid catalysis, noncovalently supported heterogeneous chiral primary amine catalysis and chiral primary amine as hydrogen-bond catalysis.

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畜禽废水是农村水环境污染的主要来源之一,其处理的难点在于脱氮。传统生物脱氮法具有能耗高、需大量外加碳源等缺点,开发低成本、高效率的新型生物脱氮技术具有重要意义。 本研究将短程硝化反硝化和厌氧氨氧化两种脱氮新技术结合,让前者为后者创造去除可降解COD、降低总氮负荷、调整pH、调整氨氮和亚硝酸盐氮浓度比例等进水条件,而后者可在无需外加碳源的条件下进一步脱氮,二者结合可成为高氨氮、低C/N废水脱氮的新途径。 试验以低碳氮比猪场废水为研究对象,首先进行了短程硝化反硝化预处理研究,同时启动并运行调控厌氧氨氧化反应器,最后以经过短程硝化反硝化预处理的猪场废水为进水,进行厌氧氨氧化脱氮考察。实验表明:(1)短程硝化反硝化作为厌氧氨氧化的预处理工序是可行的。猪场废水通过短程硝化反硝化,可以达到基本去除可生化COD、部分脱氮、控制出水氨氮和亚硝酸盐氮浓度之比在1︰1左右、pH在7.5~8.0的目的, COD和总氮平均去除率分别为64.3%、49.1%,出水可达到厌氧氨氧化反应的进水要求。(2)采用模拟废水启动厌氧氨氧化反应器,经过5个月左右的运行调控,反应器启动成功并稳定运行,最高总氮去除率为87.1%,总氮容积去除率最高达到0.14kg/m3.d;整个稳定阶段,氨氮、亚硝酸盐氮、硝酸盐氮的变化量之比为1︰1.21︰0.33。(3)经过短程硝化反硝化预处理的猪场废水厌氧氨氧化脱氮效果稳定,氨氮、亚硝酸盐氮、总氮、COD的平均去除率分别为93.0%、99.4%、84.6%、18.1%,处理效果与模拟废水处理系统相比无明显变化。(4)经过短程硝化反硝化预处理后,猪场废水中残留有机物成分在厌氧氨氧化反应过程中无显著变化,主要为酯类和烷烃类物质;残留有机物对厌氧氨氧化效果无明显影响。(5)采用PCR技术进行特殊功能菌种检测,结果表明模拟废水处理系统和猪场废水处理系统的菌群中均含有厌氧氨氧化菌和好氧硝化菌;通过blast比对,厌氧氨氧化菌扩增序列与未培养的Planctomycetales菌和Candidatus Brocadia fulgida菌16S rRNA部分序列相似性分别为95%、90%。(6)MPN法菌种计数结果显示,模拟废水处理系统和猪场废水处理系统的菌群中均含有硝化细菌、亚硝化细菌和少量反硝化菌,实验条件下的微生物系统是一个厌氧氨氧化菌与好氧硝化菌、反硝化菌共存的系统。 Poultry wastewater is one of the main source of water pollution in rural areas,and nitrogen removal is the most difficult part in treating poultry wastewater. There are some disadvantages in traditional nitrogen removal, such as high energy consumption and more additional organic carbon. It is important to develop ecolomical and efficient technologyies. Shortcut nitricfication/denitrification, as a pretreatment process, was combined with Anammox in this research, so that part of total nitrogen and most degradable COD could be removed by the former, and further nitrogen removal could be implemented by the latter. The combination of the two technologies was a new approach to treat wastewater with high ammonium and low C/N. Piggery wastewater with low C/N was treated in lab-scale experiment. Firstly, shortcut nitrification/denitrification was investigated, and Anammox reactor was started up successfully at the same time. Then piggery wastewater after pretreatment was treated by Anammox. The results showed :(1) It was feasible to take nitrification/denitrification as the pretreatment process of Anammox. By using this process, part of total nitrogen and COD were removed, the ratio of ammonium and nitrite reached around 1︰1 and the pH was about 7.8, which were favorable for Anammox. The average removal percentage of COD and total nitrogen were about 64.3% and 49.1%, respectively. (2) Simulated wastewater was used to start up Anammox reactor. The reactor was started up successfully within 5 months and stable performance was achieved. The highest nitrogen removal reached 87.1% and the biggest volumetric total nitrogen removal rate reached 0.14kg/m3.d. The average ratio of ammonium, nitrite and nitrate was 1:1.21:0.33. (3)Taking the effluent of shortcut nitrification/denitrification as the influent, the nitrogen removal efficiency of Anammox was stable, and the the average removal percentage of ammonium, nitrite, total nitrogen and COD were 93.0%, 99.4% , 84.6% and 18.1%, respectively, which had little difference with that by using simulated wastewater..(4) After pretreatment, the residual organic carbon in piggery wastewater showed no obvious change during the Anammox process, and the main organic compounds were saturated hydrocarbon and ester, which had no obvious negative effect on Anammox process.(5) By PCR technology, the existence of Anammox bacteria was confirmed and the aerobic nitrifying bacteria was found to coexist as well. The result of blast showed that the identities of Anammox bacterium to part of 16S rRNA sequence of uncultured Planctomycetales bacterium and Candidatus Brocadia fulgida bacterium were 95% and 90%, respectively.(6)By MPN method, nitrite oxidizer, ammonium oxidizer and denitrification bacteria were detected in both simulated and piggery wastewater treatment system of Anammox, and the microorganism system was composed of Anammox bacteria,aerobic bacteria and denitrification bacteria together.

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Chiral ferrocene-based phosphine-imine ligands 1-3 and sulfur-imine ligand 4 were applied in the palladium-catalyzed asymmetric allylic alkylation of cycloalkenyl esters. The results revealed that the substitutents in aryl ring, ferrocenylmethyl and benzyliene position strongly affected the enantioselective induction of phosphine-imine ligands, and the most stereoselective ligand was ferrocenylphosphine-imine 1b with a nitro group in the meta-position of phenyl ring. Under the optimized condition, up to 91% (enantiomeric excesses) e.e. of cyclic alkylation product was obtained by the use of 1b. (C) 2004 Elsevier B.V. All rights reserved.

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A series of novel ferrocenylphosphine-ketimine ligands 6 were prepared by reaction of (R,S-p)-PPFNH2-R or (S,S-p)-PPFNH2 with a variety of m-substituted acetophenones. A different catalytic activity was observed between ferrocenylphosphine-ketimine ligands and corresponding aldimine ligands. The efficiency and diastereomeric impact of these ferrocenylphosphine-ketimine ligands in Pd-catalyzed asymmetric allylic alkylation were first investigated, and higher enantioselectivity of over 98% e.e. with 95% yield was obtained by the use of ferrocenylphosphine-ketimine ligands. However, in Rh-catalyzed asymmetric hydrosilylation of aryl ketones, only 42% e.e. was obtained by the use of ferrocenylphosphine-ketimine ligands compared to 90% e.e. with the use of aldimine ligands. (C) 2003 Elsevier Ltd. All rights reserved.

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为获得更为丰富的石油降解微生物资源,从沈抚污灌区石油污染土壤和实验室高浓度柴油胁迫土壤中筛选出了4株高效石油烃降解菌SF-422、SF-428、SF-433和SYS-1.这4株菌总石油烃(Total petroleum hydrocarbon/TPH)生物降解率为67.4%~73.6%.经过16项生理生化特性实验和16S rDNA序列分析鉴定,SF-433,SF-428,SF-422和SYS-1分别为蜡状芽孢杆菌(Bacillus cereus),木糖氧化无色杆菌(Achromobacter xylosoxidans),施氏假单胞菌(Pseudomonas stutzeri)和洋葱伯克霍尔德氏菌(Burkholderia cepacia).纯烃降解定性实验表明所筛选出的4株高效降解菌均能够利用正十六烷、苯、菲和环己烷为唯一碳源生长,其中菌株SF-428和SYS-1显示了对芳烃及环烷烃较强的利用能力.