6－（N－吡啶）氨基－1－甲基－1H－吲唑类化合物的设计与合成

以3－甲基－6－硝基吲唑为起始原料,经N－甲基化、还原、烷基化反应得到三个未见文献报道的6－（ N－吡啶）氨基吲唑类化合物。目标化合物及中间体结构经1 H－NMR、ESI－MS确证。     

响应面法优化2－甲基－3－氨基吡啶－5－硼酸频哪酯的合成

以2－甲基－3－硝基吡啶－5－硼酸频哪酯为原料,经Pd／C催化氢化得到2－甲基－3－氨基吡啶－5－硼酸频哪酯。探讨反应温度、反应时间及催化剂用量3个单因素对收率的影响,利用Box－Behnken中心组合实验,得到最佳工艺条件为：在40℃温度下,m（催化剂）∶m（原料）＝5∶100,反应时间为25 h,得到产物收率最高（87．56％）。     

国产甘薯叶黄酮类成份研究

用高效液相色谱法首次分离和制备了国产甘薯叶中黄酮类化合物，经波谱分析，分别鉴定为：桷皮素－３－０－β－Ｄ－葡萄糖－（６－→１）－０－α－Ｌ－鼠李糖甙（１），４‘，７－＝甲氧基山柰酚（２），桷皮素－３－０－β－Ｄ－葡萄糖甙（３）和桷皮素（４）。     

3-烷基-4-氨基-1，2，4-三唑-5-硫酮席夫碱的合成

以脂肪酸和β－羟基萘甲醛为原料合成了一类新型1,2,4－三唑席夫碱,其结构经^1H NMR,IR表征．     

曲酸衍生物的制备及其反应机理研究

制成了一种活性稳定、能有效抑制黑色素形成、且对皮肤无副作用的曲酸衍生物５－羟基－２－乙氧基甲基－ｒ－吡喃酮。产物经元素分析、ＩＲ、ＵＶ和＾１ＨＮＭＲ确证为目标物。对其反应机理进行了研究。     

细基江篱繁枝变形种Gracilaria tenuistipitata var.中的甾醇化合物

从细基江篱繁枝变形种Gracilaria tenuistipitata var.中分离、鉴定出8种甾醇:胆甾一5,22E-二烯-3β-醇,24-甲基-胆甾-5,22E-二烯-3β-醇,24,26-二甲基-胆甾-5,22E-二烯-3β-醇,24-亚甲基胆甾醇,26-甲基-24-亚甲基-胆甾醇,胆甾醇,24-甲基-胆甾醇及24、26-二甲基胆甾醇。     

β-甲基萘的分离精制研究

摘要：文章简要介绍了目前β-甲基萘分离精制的工艺研究现状,在此基础上经过多次实验,提出一种新的β-甲基蔡生产方法,即把工业甲基萘经两次酸洗后,一次精馏就得到含量大于96％的产品,收率可达60％,高于国内现有生产水平。     

水杨酸诱导植物抗病的研究进展

植物中水杨酸的重要生理功能是诱导植物抗病。植物中水杨酸由反式肉桂酸经苯甲酸而合成,限速步骤是反式肉桂酸的β－氧化。     

利用α-氨基烷基膦酸酯合成高生物活性化合物

按照文献合成α-氨基膦酸配体N-(正丙基)氨基-(2′-羟基苯基)甲基膦酸单乙酯(L1),利用L1与氧化钐在130℃下回流反应3h合成配合物,用红外光谱表征配合物.水杨醛和β-溴代乙胺schiff碱与亚磷酸二乙酯的加成反应,合成了新的α-氨基膦酸配体N-(β-溴代乙基)氨基-(2′-羟基苯基)甲基膦酸单乙酯,其结构经红外光谱、1H-NMR核磁共振进行表征.     

高考数学模拟试卷（四）嘉兴市高三教学质量检测命题小组

参考公式：三角函数和差化积公式：ｓｉｎα＋β＝２ｓｉｎα＋β／２&;#183;ｃｏｓα－β／２；ｓｉｎα－ｓｉｎβ＝２ｃｏｓα＋β／２&;#183;ｓｉｎα－β／２；ｃｏｓα＋ｃｏｓβ＝２ｃｏｓα＋β／２&;#183;ｃｏｓα－β／２；ｃｏｓα－ｃｏｓβ＝－２ｓｉｎα＋β／２&;#183;ｓｉｎα－β／２．     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.