含双酰腙类新型席夫碱大环化合物的合成与表征

报道以草酸、邻苯二胺为原料,合成中间体N,N′-双(2-苯氨基)-乙二酰胺(1),然后中间体(1)再与乙酰丙酮反应,合成得到了新型席夫碱大环化合物(2)。并探讨了合成目标大环化合物的最佳合成条件:以50%乙醇做溶剂,在高度稀释下中间体(1)与乙酰丙酮投料比(摩尔比)为1∶1,反应液pH值7~8,于75~80℃条件下反应18 h。目标大环化合物通过元素分析、1H NMR、IR、UV-vis和MS进行组成和结构表征。     

NO供体型香豆素-3-羧酸衍生物的合成

以水杨醛与丙二酸二乙酯为原料制备香豆素-3-羧酸,利用其羧基与不同碳数的二溴烷烃反应得到相应的香豆素-3-羧酸溴代烷基酯,再与硝酸银反应生成香豆素-3-羧酸-硝氧烷基酯。目标化合物的结构经过红外光谱、核磁共振氢谱和质谱确证。考察了目标化合物合成中温度及投料比对反应的影响,得到最佳反应条件为:反应温度60℃,反应物配比n(香豆素-3-羧酸溴代烷基酯)∶n(硝酸银)=1∶3,此条件下目标化合物收率可达55.3%~90.8%。     

[C_3H_(12)N_2]_3[P_2Mo_5O_(23)]·4H_2O单晶体的水热合成及其催化合成阿司匹林的研究

利用水热法制备了单晶体化合物[C_3H_(12)N_2]_3[P_2Mo_5O_(23)]·4H_2O(1),并通过单晶X-射线衍射和元素分析对其进行了结构表征。通过正交试验对其催化合成阿司匹林的性能进行了初步研究,确定了其催化合成阿司匹林的最佳条件:催化剂用量0.15 g,反应时间为30 min,反应温度85℃。表明该单晶体化合物可以替代传统催化剂浓硫酸合成阿司匹林,有望成为未来绿色制药工业的新型催化剂。     

2-氨基-1H-苯并[d]咪唑-5-羧酸的合成

3,4-二氨基苯甲酸甲酯(化合物1)与溴化氰反应得到2-氨基-1H-苯并[d]咪唑-5-羧酸甲酯(化合物2),之后在碱性条件下水解得到目标化合物2-氨基-1H-苯并[d]咪唑-5-羧酸(化合物3),其结构经1H NMR、13C NMR和MS确证,并对中间体2的合成条件进行优化:物料比n(化合物1):n(溴化氰)=1:3,反应溶剂为甲醇与水的1:1混合溶液,反应温度为50℃,反应时间为2 h.在上述条件下,化合物2收率达到97％,目标化合物的总收率为90％.该方法为苯并咪唑衍生物的合成提供了参考.     

研磨法合成α-羟基膦酸酯

以芳香醛(2a～2h)和亚膦酸二乙酯(3)为原料、三乙烯二胺(DABCO)为有机碱,采用研磨法一步合成α-羟基膦酸酯(1a～1h),通过¹HNMR对其结构进行了表征,并对合成条件进行了优化。结果表明,以目标化合物(苯基)(羟甲基)膦酸二乙酯(1a)的合成为模型反应,确定最佳合成条件如下：物料比n(亚膦酸二乙酯)∶n(苯甲醛)为1.8∶1、DABCO用量n(DABCO)∶n(苯甲醛)为0.5∶1、研磨时间为15 min,在此条件下,目标化合物1a收率达到83.6%。     

2-氨基-5-溴-3-吗啉-4-基吡嗪的合成

以2-氨基吡嗪(Ⅰ)为原料,经溴代、吗啉取代,合成得到目标化合物2-氨基-5-溴-3-吗啉-4-基吡嗪(Ⅲ),合成路线总收率为45.9%(以2-氨基吡嗪计),目标化合物结构经1HNMR确证。该文对反应投料比、温度、反应时间等因素进行了考察并优化,最优反应条件为:n(2-氨基吡嗪)∶n(溴素)∶n(吡啶)=1∶2.1∶2.1,避光,40℃下反应30 min;每克3,5-二溴-2-氨基吡嗪加入4 mL吗啉,80℃下反应1 h。优化后的合成路线反应条件温和、操作简单、成本低廉,适合较大规模制备。     

酰胺类NO供体熊果酸衍生物的合成

为提高五环三萜类天然产物熊果酸的抗肿瘤活性,以熊果酸为母核引入具有广泛生物活性的酰胺结构以及具有抗肿瘤作用的NO供体支链形成酰胺类NO供体型熊果酸衍生物。采用熊果酸为原料,经氧化、亲核取代等多步反应合成8个酰胺类NO供体熊果酸衍生物2、12～18,所有化合物采用IR、~1H NMR、~(13)C NMR、HR MS进行表征。     

2-(2-氯甲基苯基)乙基苯甲酸酯的合成工艺改进

以苯乙醇为原料,通过成环、开环反应,合成了2-(2-氯甲基苯基)乙基苯甲酸酯(3),并改进了合成工艺。改进后的工艺条件为:水相盐酸浓度6 mol/L,n(甲醛)∶n(苯甲酰氯)∶n(氯化锌)∶n(1)=3.5∶1.03∶0.7∶1,成环、开环反应时间分别为13 h和10 h。优化条件下目标化合物收率达81.6%。目标化合物的结构经1H NMR确证。改进后的工艺降低了成本,简单可行,适合工业化生产。     

NO供体型丹皮酚衍生物的合成及其生物活性研究

以丹皮酚与溴乙酸为原料制备丹皮酚乙酸,利用其羧基与不同碳数的二溴烷烃反应得到相应的丹皮酚乙酸溴代烷基酯(3a~3e),再与硝酸银反应生成目标化合物NO供体型丹皮酚衍生物4a~4e。目标化合物的结构经过红外光谱、核磁共振氢谱和质谱确证。对合成的NO供体型丹皮酚衍生物进行体外抗血小板聚集及体内调血脂作用的生物活性测试,结果表明,目标化合物均具有一定的体外抗血小板聚集活性及较强的体内降脂作用,其中化合物4c的活性最强。     

超声催化合成新型含硫席夫碱大环化合物

以草酸、邻胺基硫酚为原料,合成中间体S,S′-双(2-苯氨基)-乙二酰硫(1),采用超声波技术在温和条件下将中间体(1)与邻苯二甲醛反应,合成得到了新型含硫席夫碱大环化合物(L)。并与常规加热法进行了对比。结果表明:超声波催化法具有操作简单、反应时间短、条件温和、产率高及副反应少等优点。并探讨了超声波催化下目标大环化合物的最佳合成条件:以乙醇做溶剂,在中间体(1)与邻苯二甲醛摩尔比为1∶1,于50℃条件下超声1.5h。所有化合物均通过元素分析、1 HNMR、IR和MS进行组成和结构表征。     

Nitrosylmetallochelates—II. composition of FeNO—aminocarboxylic acid complexes in solution

Absorptive properties of nitric oxide by Fe(II)—aminocarboxylic acid complexes have been investigated, and the compositions of the Fe(II)NO—chelate complexes in solution determined by the electrochemical and spectroscopic methods. Fe(II)—EDTA forms the 1:2 complex (Fe(II) (NO)₂EDTA) with nitric oxide, —G and—EDDA the 1:1 complexes, and—NTA and—IDA both of the 1:1 and 1:2 complexes. The abilities of the Fe(II)—chelate complexes to absorb nitric oxide decreased in the order Fe(II)—EDTA > —NTA > —IDA > —G > —EDDA, which is in agreement with that of a decrease of its stability constant.     

A ruthenium(II) complex with bis(3,5-dimethylpyrazol-1-yl)dithioacetate built layer-by-layer on silver and gold surfaces

A ruthenium(II) complex with bis(3,5-dimethylpyrazol-1-yl)dithioacetate was self-assembled layer-by-layer on silver and gold surfaces. The two-step process and the ability of the complex to scavenge nitric oxide were studied by cyclic voltammetry.     

TRANSIENT RESPONSE ANALYSIS IN THE DETERMINATION OF ADSORPTION RATE COEFFICIENTS FOR PROPYLENE AND NITRIC OXIDE ON NiO/Al203 AEROGEL CATALYSTS

Nickel oxide on alumina aerogel catalysts are known to be active and selective for the formation of acrylonitrile from nitric oxide and propylene. During an effort to investigate the mechanism of this reaction some transient feed experiments were carried out. The results obtained from these transient experiments were used to calculate the adsorption coefficients of propylene and nitric oxide on a NiO/Al₂O₃ aerogel catalysts with 1:1 Ni to Al atomic ratio. Adsorption coefficients of nitric oxide and propylene was determined by independently flowing the respective gases over the catalyst in a stream of helium at 410° C. Adsorption coefficient of nitric oxide on the catalyst at an oxidized state has been found to be less than that of propylene. When the two reactant gases flowed across the catalyst together the rate of adsorption of nitric oxide increased as the catalyst was reduced by propylene adsorption. The increased rate of adsorption of nitric oxide does not, however, influence the overall rate of formation of acrylonitrile.     

TRANSIENT RESPONSE ANALYSIS IN THE DETERMINATION OF ADSORPTION RATE COEFFICIENTS FOR PROPYLENE AND NITRIC OXIDE ON NiO/Al203 AEROGEL CATALYSTS

Nickel oxide on alumina aerogel catalysts are known to be active and selective for the formation of acrylonitrile from nitric oxide and propylene. During an effort to investigate the mechanism of this reaction some transient feed experiments were carried out. The results obtained from these transient experiments were used to calculate the adsorption coefficients of propylene and nitric oxide on a NiO/Al₂O₃ aerogel catalysts with 1:1 Ni to Al atomic ratio. Adsorption coefficients of nitric oxide and propylene was determined by independently flowing the respective gases over the catalyst in a stream of helium at 410° C. Adsorption coefficient of nitric oxide on the catalyst at an oxidized state has been found to be less than that of propylene. When the two reactant gases flowed across the catalyst together the rate of adsorption of nitric oxide increased as the catalyst was reduced by propylene adsorption. The increased rate of adsorption of nitric oxide does not, however, influence the overall rate of formation of acrylonitrile.     

Reaction of nitric oxide and nitric oxide + carbon monoxide with amorphous Fe-Co-B alloy powders

The activity of amorphous Fe---Co---B alloy powder was investigated for the decomposition and the reduction of nitrogen monoxide. The transient response technique and a fixed bed reactor were applied to study the interactions of the Fe---Co---B alloy with two gas mixtures: NO + Ar at 353 and 573 K and NO + CO + Ar at 333–573 K. Moessbauer spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to study the state of the initial sample and the samples utilized in both gas mixtures. It is shown that the amorphous Fe---Co---B alloy powder has an activity for the direct decomposition of nitric oxide to nitrous oxide and nitrogen at a high gas space velocity (26 000 h⁻¹). Oxygen from the decomposed nitric oxide poisons the surface for the formation of nitrogen. In the presence of carbon monoxide (a NO + CO + Ar gas mixture) nitric oxide is reduced to nitrous oxide at 333–353 K and fully reduced to nitrogen at 373–573 K. The quantities of the carbon dioxide formed are not equal to the values expected from the stoichiometry of the NO + CO reaction. Probably, the interaction of carbon monoxide with the adsorbed oxygen (left on the surface by the decomposed nitric oxide) enhances the rate of nitric oxide decomposition to nitrous oxide and nitrogen. The rate limiting steps for both reactions of nitric oxide decomposition, as indicated by the transient response data, change with increasing temperature. The data from the Moessbauer spectroscopy and the X-ray photoelectron spectroscopy (XPS) studies have shown that the amorphous Fe---Co---B alloy powder undergoes phase changes under the conditions of both, the NO + Ar and the NO + CO + Ar gas mixtures. Boron migrates to the surface of globules and serves the accumulation of oxygen by the formation of B₂O₃ (or B(OH)₃).     

Characterization of an S-nitroso-N-acetylpenicillamine–based nitric oxide releasing polymer from a translational perspective

Due to the role of nitric oxide (NO) in regulating a variety of biological functions in humans, numerous studies on different NO releasing/generating materials have been published over the past two decades. Although NO has been demonstrated to be a strong antimicrobial and potent antithrombotic agent, NO-releasing (NOrel) polymers have not reached the clinical setting. While increasing the concentration of the NO donor in the polymer is a common method to prolong the NO release, this should not be at the cost of mechanical strength or biocompatibility of the original material. In this work, it was shown that the incorporation of S-nitroso-penicillamine (SNAP), an NO donor molecule, into Elast-eon E2As (a copolymer of mixed soft segments of polydimethylsiloxane and poly(hexamethylene oxide)), does not adversely impact the physical and biological attributes of the base polymer. Incorporating 10 wt% of SNAP into E2As reduces the ultimate tensile strength by only 20%. The inclusion of SNAP did not significantly affect the surface chemistry or roughness of E2As polymer. Ultraviolet radiation, ethylene oxide, and hydrogen peroxide vapor sterilization techniques retained approximately 90% of the active SNAP content and did not affect the NO-release profile over an 18-day period. Furthermore, these NOrel materials were shown to be biocompatible with the host tissues as observed through hemocompatibility and cytotoxicity analysis. In addition, the stability of SNAP in E2As was studied under a variety of storage conditions, as they pertain to translational potential of these materials. SNAP-incorporated E2As stored at room temperature for over six months retained 87% of its initial SNAP content. Stored and fresh films exhibited similar NO release kinetics over an 18-day period. Combined, the results from this study suggest that SNAP-doped E2As polymer is suitable for commercial biomedical applications due to the reported physical and biological characteristics that are important for commercial and clinical success.     

Elevation of Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Expression in the Mouse Brain after Chronic Nonylphenol Exposure

The present study was performed to investigate the effects of chronic administration of nonylphenol (NP) on the expression of inflammation-related genes in the brains of mice. NP was given orally by gavages at 0, 50, 100, and 200 mg/kg/d. The expression of inflammatory enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), was evaluated by immunohistochemistry and immunoblotting assays. The nitric oxide (NO) level and nitric oxide synthase (NOS) activity were also measured by biochemical analyses. The results showed that NP at a high dose (200 mg/kg/d) significantly increased the expression of iNOS and COX-2 in both the hippocampus and cortex. In parallel with the increase in iNOS expression, the NO level was significantly greater at the dose of 200 mg/kg/d, compared to the control. The activity of NOS was also increased in the brain of mice at the dose of 100 and 200 mg/kg/d. These findings demonstrate that NP may have the potential to induce the chronic inflammation or cause neurotoxicity in the mouse brain.     

NO与Co(NH3)2+6气液反应动力学

用Co(NH₃)²⁺₆的氨水溶液可同时实现NO的氧化和吸收过程.NO 与Co(NH₃)²⁺₆气液反应动力学研究表明,NO与Co(NH₃)²⁺₆的反应为瞬间反应,当Co(NH₃)²⁺₆浓度低于20mmol•L^-1时过程为双膜控制,当Co(NH₃)²⁺₆浓度大于20mmol•L^-1时过程逐渐变为气膜控制.NO的吸收速度随温度的升高而降低,气相中氧的存在有利于NO的吸收,但当氧的含量高于5.2%后再继续增加氧的含量NO吸收速率提高不大.经研究建立了有氧时NO 与Co(NH₃)²⁺₆气液反应动力学方程.     

Selective reduction of nitric oxide with propene over platinum-group based catalysts: Studies of surface species and catalytic activity

The reduction of nitric oxide by propene in the presence of oxygen over platinum-group metals supported on TiO₂, ZnO, ZrO₂, and Al₂O₃ has been investigated by combined diffuse reflectance FT-IR spectroscopy and catalytic activity studies under flow reaction conditions at 523–673 K and atmospheric pressure. The catalytic activity for the selective reduction of nitric oxide and the intensity of the IR bands due to reaction species depended strongly on the nature of the support, type of supported metal, reaction time and temperature. The main surface species detectable by IR were adsorbed hydrocarbons (2900–3080 cm⁻¹), isocyanate (2180, and 2232–2254 cm⁻¹), cyanide (2125 cm⁻¹), nitrosonium (1901 cm⁻¹), CO₂ (2343–2357 cm⁻¹), CO (2058 cm⁻¹) and carbonate (1300–1650 cm⁻¹) species. In the case of rhodium containing catalysts, when supported on Al₂O₃, they exhibited both the highest concentration of surface species and the highest activity for nitric oxide reduction and selectivity to nitrogen. The catalytic activity and the IR intensities of the nitrosonium and isocyanate bands increased with reaction temperature, reached their maximum between 570 and 620 K, and then decreased at higher temperatures. The IR band intensities due to nitrogen containing surface species were found to be strongly correlated to the activity for nitric oxide conversion and only slightly related to the selectivity to dinitrogen.