（CH4）15[Ce（PMo9V2O39）2].5H2O杂多配合物合成及在苯酚羟化反应中？…

合成了（ＮＨ４）１５「Ｃｅ（ＰＭｏ９Ｖ２Ｏ３９）２」．５Ｈ２Ｏ杂多化合物,并用ＩＣＰ,ＩＲ,ＵＶ,ＸＲＤ等手段对其结构进行表征,结果表明该化合物是具有Ｋｅｇｇｉｎ结构的杂多化合物。考察了该杂多化合物对苯酚过氧化氢羟化反应的催化活性,研究了反应介质、反应温度、反应时间、反应体系ＰＨ及ｍｏｌＰｈＯＨ：ｍｏｌＨ２Ｏ２对催化活性的影响。实验结果表明：以甲醇为溶剂,用标题化合物作催化剂,当ｍｏｌＰｈＯＨ：ｍ     

An assay of sulphasalazine,sulphapyridine and its acetylated and hydroxylated metabolites in biological fluids by liquid chromatography

Summary An HPLC assay was developed for the determination of sulphasalazine (salicylazosulphapyridine), and its main metabolites; sulphapyridine, acetylsulphapyridine, hydroxysulphapyridine and acetylhydroxysulphapyridine in human serum, synovial fluid and urine. Sep-Pak C₁₈ cartridge was used for the extraction of the investigated compounds and the added sulphadimidine internal standard. The methylene chloride-chloroform-methanol eluate was evaporated and the dissolved dry residue was injected onto a Hypersil ODS (100×2.1 mm) 5 m microbore, analytical column. A linear gradient was used, the mobile phase was ternary. The assay is sufficiently sensitive for routine therapeutic drug monitoring and phenotyping in patients treated with sulphasalazine.     

Non‐Heme‐Type Ruthenium Catalyzed Chemo‐ and Site‐Selective C−H Oxidation

Herein, we developed a Ru(II)(BPGA) complex that could be used to catalyze chemo‐ and site‐selective C?H oxidation. The described ruthenium complex was designed by replacing one pyridyl group on tris(2‐pyridylmethyl)amine with an electron‐donating amide ligand that was critical for promoting this type of reaction. More importantly, higher reactivities and better chemo‐, and site‐selectivities were observed for reactions using the cis‐ruthenium complex rather than the trans‐one. This reaction could be used to convert sterically less hindered methyne and/or methylene C?H bonds of a various organic substrates, including natural products, into valuable alcohol or ketone products.     

Regioselective hydroxylation of diverse flavonoids by an aromatic peroxygenase

Aromatic peroxygenases are extracellular fungal biocatalysts that selectively oxidize a variety of organic compounds. We found that the peroxygenase of the fungus Agrocybe aegerita (AaeAPO) catalyzes the H₂O₂-dependent hydroxylation of diverse flavonoids. The reactions proceeded rapidly and regioselectively yielding preferentially monohydroxylated products, e.g., from flavanone, apigenin, luteolin, flavone as well as daidzein, quercetin, kaempferol, and genistein. In addition to hydroxylation, O-demethylation of fully methoxylated tangeretin was catalyzed by AaeAPO. The enzyme was merely lacking activity on the quercetin glycoside rutin, maybe due to sterical hindrance by the bulky sugar substituents. Mechanistic studies indicated the presence of epoxide intermediates during hydroxylation and incorporation of H₂O₂-derived oxygen into the reaction products. Our results raise the possibility that fungal peroxygenases may be useful for versatile, cost-effective, and scalable syntheses of flavonoid metabolites.     

CuO+氧化苯直接形成苯酚反应机理的理论研究

在UB3LYP/6-31G(d,p) 水平下研究了CuO+氧化苯形成苯酚反应的详细机理,同时计算了单重态和三重态势能面。计算结果表明,苯与CuO+间相互作用主要为?配键,反馈?键较弱. CuO+氧化苯形成苯酚反应通过非自由基氢摘取机理完成,主要包括C-H键活化和苯基与羟基耦合两步反应. C-H键活化为整个反应的决速步骤. C-H键活化步骤涉及势能面交叉,且自旋交叉与动力学相关。CuO+氧化苯形成苯酚反应在气相中很容易进行.     

掺杂Fe作为第二种金属组分的V-HMS催化剂的苯羟基化反应

采用浸渍法在V-HMS中引入第二种金属组分(Fe、Al、Cu、Ni、Co、Mo、Cr)以提高催化剂在H2O2为氧化剂的苯羟基化反应中的催化性能.筛选发现,Fe在所研究的金属组分中最为有效.进一步采用共合成法制备了一系列FexVy-HMS催化剂.采用粉末X射线衍射、N2物理吸附、透射电子显微镜、NH3程序升温脱附、H2程序升温还原等手段对催化剂的结构和性质进行表征,结果表明,HMS仍保持介孔结构,Fe的加入在催化剂中产生了新的酸性位和更强的氧化还原性.在苯羟基化反应中,钒物种是反应活性物种,铁物种起助剂作用,其中Fe0.04V0.06-HMS具有最高的催化活性,苯酚收率由不含Fe的Fe0.00V0.06-HMS的13.1%提高到18.1%.提出了Fe、V参与反应过程的可能机理.