New Potential Antitumor Pyrazole Derivatives: Synthesis and Cytotoxic Evaluation

New pyrazole derivatives were designed and synthesized as potential protein kinase inhibitors in the view to develop specific antitumor therapies. The structures of the compounds were elucidated using spectral and elemental analyses. The antitumor potential was estimated using wheat seeds and the general toxicity was evaluated by alternative methods, using invertebrate animals. One 3-aminopyrazole derivative emerged as a potential candidate for the development of future cytotoxic compounds.     

Sodium dithionite and its relatives: past and present

In this paper, the implications of sodium dithionite and of some of its related compounds for the development of chemistry in the twentieth century, as well as their applications in newer fields of chemistry, are described.     

[2.2]Paracyclophane-Derived Planar-Chiral Hydrogen-Bond Receptors

The development of planar-chiral hydrogen-bond donors based on the [2.2]paracyclophane scaffold is discussed. General strategies to access functionalized enantiopure [2.2]paracyclophane derivatives are briefly reviewed, with the focus on suitable precursors for the synthesis of planar-chiral thiourea derivatives. The synthesis of fourteen hydrogen-bond donors is described. The interaction of four thiourea derivatives with hydrogen-bond acceptors (DMSO and tetramethylammonium chloride) was investigated by ¹H NMR spectroscopy and X-ray crystallography. A selection of enantiomerically pure planar-chiral derivatives was applied in asymmetric hydrogen-bond catalysis.     

相转移催化合成N-烯丙基-N′-(氨基对苯磺酸钠)硫脲的一种新方法

用聚乙二醇 - 40 0作相转移催化剂合成异硫氰酸烯丙酯 ,不经分离直接与对肼基苯磺酸钠反应制得化合物 N-烯丙基 - N′- (氨基对苯磺酸钠 )硫脲。方法简单、经济     

Facile and regioselective synthesis of thiazolidin-4-one derivatives catalyzed by basic ionic liquid [bmim]OH under ultrasonic irradiation

2-Iminothiazolidin-4-one derivatives were synthesized regioselectively in good to high yields by condensation of N,N-disubstituted thioureas and ethyl chloroacetate in the presence of basic ionic liquid [bmim]OH as a catalyst under conventional and ultrasonic irradiation conditions. Under ultrasonic irradiation, the reaction furnished the desired 2-iminothiazolidinones in higher yields (76–87%) and lower reaction times (30–55 min).     

二苯基乙醛的合成

以二苯甲酮和氯乙酸乙酯为起始原料,通过3步反应制得二苯基乙醛：首先,二苯甲酮与氯乙酸乙酯在氢化钠作用下,反应温度〈20℃,制得3,3-二苯基-2,3-环氧丙酸乙酯;然后,在甲醇钠作用下,反应温度〈20℃水解制得3,3-二苯基-2,3-环氧丙酸钠;最后,在盐酸水溶液中回流脱羧制得二苯基乙醛。3步反应总收率为83.1%。     

氰化法、硫代硫酸盐法、硫脲法浸出某难浸银精矿比较研究

对某浮选银精矿采用氰化法、硫代硫酸盐法、硫脲法进行银浸出实验,以评估3种不同浸出方法对该银精矿浸出效果．研究结果表明：在最优的工艺参数下[氰化法：碱预处理后加入铵盐,氰化钠浓度0.15 mol/L,pH值为11,液固比（浸出液体积与试样质量之比,单位是mL/g,下同）2∶1,搅拌强度500 r/min,浸出时间为48 h;硫代硫酸盐法：氧化焙烧预处理,氨水浓度1.0 mol/L,硫酸铜浓度0.01 mol/L,硫代硫酸钠浓度0.2 mol/L,pH值为10,液固比4∶1,搅拌强度500 r/min,浸出时间12 h;硫脲法：氧化焙烧和稀硫酸预浸处理,Fe3+浓度7.5×10-3 mol/L,硫脲浓度0.18 mol/L,pH=1.0,液固比为3∶1,搅拌速度250 r/min,浸出时间24 h],硫代硫酸盐方法获得的Ag浸出率为78.58%,硫脲相应获得的Ag浸出率为62.43%,比氰化法获得的浸出率低约3.33%．     

异丙硫醇的合成研究

研究了以2-溴丙烷和硫脲为原料,在相转移催化剂四丁基溴化铵的作用下,以水作溶剂,制得 S -异丙基异硫脲盐,并在氢氧化钠水溶液中水解,酸化,制得了标题化合物.用气相色谱和红外光谱对其含量和结构进行了分析.     

1-[苯基(4-甲氧苯基亚胺基)甲基]-3-(1-萘基)硫脲的合成

以N-(4-甲氧基)苯基苯甲酰胺和二氯亚砜为原料,经氯代反应制得氯代4-甲氧基苯基苯甲酰亚胺(2),2与硫氰酸钠加成得中间体N-(异硫氰酸基(苯基)亚甲基)-4-甲氧基苯胺(3)后,与1-萘胺经加成反应合成得到最终产物1-(苯基(4-甲氧苯基亚胺基)甲基)-3-(1-萘基)硫脲(4),总收率为72.6%。合成化合物3的适宜工艺条件为:n(2)∶n(硫氰酸钠)=1∶1.2,丙酮为溶剂,反应温度为-15℃,反应时间3h。     

胸腺嘧啶合成改进

以丙酸乙酯、甲酸乙酯、硫脲、双氧水等为原料,经缩合、环合、氧化及中和4步反应,合成胸腺嘧啶产品。反应总收率达64．5％（以丙酸乙酯计,n／n）,经红外鉴定结构。该工艺原料易得,操作简单,适于工业化生产。