Linear sweep voltammetry of 9-β- -ribofuranosyluric acid 5′-monophosphate in aqueous and micellar media

Linear sweep voltammetric behaviour of 9-β- -ribofuranosyluric acid 5′-monophosphate (UA-9R-5′-P) has been studied in phosphate buffers of pH 3.0 and 7.0 at the pyrolytic graphite electrode in aqueous and micellar media. At pH 3.0 in the presence of non-ionic and anionic surfactants, UA-9R-5′-P exhibited a single well-defined 2e, 2H⁺ oxidation peak, whereas in the presence of cationic surfactant (CTAB) the oxidation peak I_a showed a tendency to split into two peaks indicating that the 2e, 2H⁺ oxidation of UA-9R-5′-P in peak I_a reaction occurs in two 1e steps. The effect of cationic surfactant at pH 3.0 is explained on the basis of hydrophobic penetration of cationic species in cationic micelles. The products of electrode reaction in micellar medium were found as alloxan, urea and ribosyl phosphate at pH 3.0 and ribose, allantoin and 5-hydroxyhydantoin 5-carboxamide at pH 7.0 and were similar to those observed in aqueous media.     

碳数规律中值与固定液极性的关系

采用n-烷烃在不同极性的固定液中,在不同色谱柱温下试验的大量数据表明,碳数规律中A、B'值与柱温倒数(1/T)的关系中,(e)A/(e)(1/T)值随固定液极性增加而增大;(e)B'/(e)(1/T)值随固定液极性增加而减小,即(e)A/(e)(1/T)值与Mertynolder常数成正比;(e)B'/(e)(1/T)值与Mertynolder常数成反比.     

1Π态双原子分子中关于量子干涉的微分干涉角

Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,1022772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.     

由盐一锅法合成α-苯硫基-α,β-不饱和羰基化合物

在三乙胺存在下,(钅申)盐与苯硫基氯化物反应,然后与醛反应,产生相应的α-苯硫基-α,β-不饱和羰基化合物,构型以(Z)-型为主,产率良好.     

开链冠醚型手性双(噻)唑啉配体的合成及其应用研究

合成了6个新的具有开链冠醚结构的手性双噁唑啉配体(4a～4d)和手性双噻唑啉配体(5b,5c),用红外光谱、核磁共振氢谱、核磁共振碳谱、元素分析等对其结构进行了表征.初步考察了其在Henry反应中的不对称催化活性.     

1,5-苯并硫氮杂-α,α-二甲基-β-内酰胺衍生物的合成、表征及晶体结构

利用异丁酸乙酯、异丁酸异丙酯、异丁酸薄荷醇酯和LDA作用形成烯醇锂盐，然后和1,5-苯并硫氮杂     

2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂的合成及镇静活性的研究

以豆腐果苷为原料,与4-取代苯乙酮发生Claisen-Schimidt反应,得到一系列E-4-β-D-吡喃阿洛糖苷-苯乙烯基-4-取代苯酮衍生物1a～1e,再将1a～1e与邻氨基苯硫酚发生1,4-Michael反应,得到2-(4-β-D-吡喃阿洛糖苷-苯基)-4-芳基-2,3-二氢-1,5-苯并硫氮杂革衍生物2a～2e,以上化合物均未见文献报道,其结构经1H NMR,IR,MS加以确证,并对2a～2e进行了药理活性筛选.结果表明,部分化合物具有良好的镇静活性.其中,化合物2a(200 mg·kg-1),2b(200 mg·kg-1),2c(200 mg·kg-1),2d(200 mg·kg-1),2e(200 mg·kg-1)与豆腐果苷相比较具有更强的活性.     

Nickel-catalyzed CH trifluoromethylation of pyridine N-oxides with Togni’s reagent

The first nickel-catalyzed CH trifluoromethylation of pyridine N-oxides with Togni’s reagent has been achieved. Trifluoromethylation proceeds smoothly under mild conditions with moderate functional group compatibility. Notable advantages of this method include the using of low cost of nickel catalyst, and its simple convenient operation.     

Efficient synthesis of α-substituted-α-arylmethyl phosphonates using trichloroacetimidate CC coupling method

A simple convenient protocol for the synthesis of diethyl α,α-diaryl methylphosphonate derivatives 5a-f, 6b-f, 7a-f and 8a-f, diethyl α-alkenyl α-aryl methylphosphonates 9a-d and 10a-d and α-(oxoalkyl) α-aryl methylphosphonate 11a-d and 12a-d is described. Trichloroacetimidates 3a-d were treated with activated arenes, styrene, allyltrimethylsilane or silylenol ethers C-nucleophiles in the presence TMSOTf to afford the desired products in good yields and short reaction time.     

生态工业系统分析

利用热力学分析方法研究了生态工业系统内物质、能量流动和利用的复杂模式, 反映了其资源利用的热力学本质; 在分析的基础上, 建立了系统消耗指数、物质循环利用效率等一系列评价指标, 反映了系统资源利用的效果和对环境的潜在影响. 在案例分析的基础上, 进一步分析了指标的工业生态学内涵以及指标之间的关系, 研究结果表明了分析方法的有效性和评价指标的实用性.     

1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并嗪)基]乙烷的合成及晶体结构

~~1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并噁嗪)基]乙烷的合成及晶体结构@徐小平$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @姚英明$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @赵艺萍$江阴市长泾中学!江苏江阴214411 @张勇$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @沈琪$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州2150061,2-二[3-(6,8-二叔丁基.3,4-二氢-1,3-苯并噁嗪)基]乙烷;;合成;;晶体结构[1] Neuvonen K,Pihlaja K. J. Chan. Soc…     

微波作用下1,5-苯并硫氮杂-α-溴代-β-内酰胺衍生物的合成

1,5-苯并硫氮杂     

A bio-inspired cascade and a late-stage directed sp3 CH lithiation enables a concise total synthesis of (−)-virosaine A

The asymmetric total synthesis of (?)-virosaine A was achieved in 9% overall yield from commercially/readily available starting materials. Inspired by an intriguing biosynthetic proposal, a novel cascade reaction sequence was developed to efficiently construct the caged polycyclic core of virosaine A. The pivotal cascade precursor was readily available in enantiopure form via a robust route that featured an enantioselective one-pot Diels-Alder cycloaddition/organolithium addition. Several contemporary methods of CH functionalization were applied to the cascade product and yielded a diverse set of novel complex polycycles. Ultimately, a combination of NMR and computational analyses laid the groundwork for a successful directed lithiation strategy to selectively functionalize the caged core and complete the total synthesis of virosaine A.