Pyridine, 2-bromo-5-phenyl-

2-% E6% BA% B4 - 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6%E7%9A%84%E5%8C%96%E5%AD%A6%E6%80%A7%E8%B4%A8%E4%B8%8E%E5%85%B6%E4%BD%93%E6%80%81%E5%92%8C%E7%94%A8%E9%80%94%E5%AF%B9%E5%BA%94%E6%9C%89%E5%A4%9A%E7%A7%8D%E7%89%B9%E6%80%A7.
2-% E6% BA% B4, that is, carbon disulfide, is a colorless transparent and slightly aromatic fat-soluble liquid at room temperature and pressure. It is flammable, explosive and irritating. Its vapor is heavier than air and can spread to a considerable distance at a lower place. It can cause combustion and explosion in case of open flame and high heat. Carbon disulfide can dissolve sulfur elemental matter, white phosphorus, etc. It is a good organic solvent and is often used in the chemical industry to make viscose fibers, cellophane, etc. Chemically, carbon disulfide can react with oxygen to generate carbon dioxide and sulfur dioxide; it can react violently with some metals such as sodium and potassium under specific conditions.
5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6, that is, 5-fluorouracil, is a fluoride of the pyrimidine class, which belongs to the anti-metabolic and anti-tumor drugs. Chemically, it is white to light yellow crystalline powder, slightly soluble in water, dissolved in dilute alkali. 5-fluorouracil can be converted into 5-fluorouracil deoxynucleotide in the body, inhibits thymine nucleotide synthase, prevents deoxyuridine methylation to deoxythymidine, thereby affecting DNA synthesis. At the same time, it can also be incorporated into RNA to interfere with protein synthesis and play an anti-tumor effect. Due to its unique chemical properties, it is widely used in chemotherapy for a variety of cancers, such as colorectal cancer, stomach cancer, breast cancer, etc. However, it can also be accompanied by adverse reactions such as nausea, vomiting, and bone marrow suppression. Therefore, it is necessary to carefully weigh the pros and cons when using it.

2-% E6% BA% B4 - 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6%E7%9A%84%E7%89%A9%E7%90%86%E6%80%A7%E8%B4%A8%E5%A6%82%E4%B8%8B%E6%89%80%E8%BF%B0:
2-% E6% BA% B4, it is smooth in nature, clear in color and light in weight. It often flows under the flow, with cold nature. When heated, it melts, when cold, it condenses. Its flow is also soothing and continuous, which can moisturize all things. If it is contained in the vessel, it changes with the shape of the vessel, and it has no shape.
5-%E8%8B%AF%E5%9F%BA%E5%90%A1, the texture is hard, the color is heavy and the quality is heavy. Its properties are stable and can bear heavy loads. It is placed on the ground, stable but not moved. It is not easy to deform due to external impact, but if the force is too strong, it is also at risk of cracking. Its body is dense, water is difficult to seep, and fire is difficult to melt. Under normal temperature, its properties are stable.
Compared with the two, 2-% E6% BA% B4 is flexible and changeable, and takes softness as its nature; 5-%E8%8B%AF%E5%9F%BA%E5%90%A1 is rigid and stable, and takes rigidity as its quality. 2-% E6% BA% B4 can flow with the trend and nourish all things; 5-%E8%8B%AF%E5%9F%BA%E5%90%A1 can settle down and support heaven and earth. 2-% E6% BA% B4 coagulates in case of cold, turns soft to hard; 5-%E8%8B%AF%E5%9F%BA%E5%90%A1 calcined by fire, or changes its shape, turns rigid to soft.
Therefore, the physical properties of 2-% E6% BA% B4 and 5-%E8%8B%AF%E5%9F%BA%E5%90%A1, rigidity and softness, change thousands of times, is the wonder of heaven and earth creation.

The common synthesis methods of 2-% -5-silylpyridine are as follows:
First, the silicon group is introduced into the starting material of the pyridine-containing compound by the inverse substitution of the silicon group. For example, if you take the first-generation pyridine, under the inverse component, the silicon-containing nucleus is inverse. This method can promote the formation of the second-generation pyridine, making it easier to attack the position of the atom of the second-generation pyridine, and generate the second-generation target 2-% -5-silylpyridine. The advantage of this method is that the starting material is easy to obtain, the inverse component is integrated, and multiple chambers can be operated. However, there may be side reactions, the degree of inverse substance is reduced, and the inverse property needs to be controlled.
The second is the even-reverse synthesis catalyzed by gold. Borate esters or compounds with a pyridine skeleton, silicon-based compounds or silicoborates, etc., are generated under the action of gold catalysis (such as gold catalysis). Gold catalysis can effectively activate the reaction substrate and promote the formation of carbon-silicon. The advantage of this method is that the reaction efficiency is high, the reaction rate can be obtained, and the reaction position is good. It can finely introduce the% group at the second position of pyridine and the silicon group at the fifth position. However, the cost of gold catalysis is usually high, and the reaction may involve the retention of gold. It needs to be properly solved to meet the degree requirements.
The third is to use the reaction strategy. Before the silicon-containing compound and the pyridine-containing fragment, the molecule is transformed and reacted to build the compound. This reaction requires careful preparation of the substrate, so that under specific conditions, the molecules interact with each function to form 2-% -5-silylpyridine pyridine and silyl substitutions. The characteristic of this approach is that it is built in one step and has high atomic stability. However, the degree of synthesis of the substrate may be high, and the reaction parts need to be precisely controlled, so that it is easy to generate multiple side effects.

2-% E6% BA% B4 - 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6%E5%9C%A8%E5%A4%A9%E4%B8%8B%E5%90%84%E9%A2%86%E5%9F%9F%E5%A4%9A%E6%9C%89%E5%BA%94%E7%94%A8.
In the field of agricultural mulberry, it can help cultivation. 2-% E6% BA% B4 and 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6 can make the soil fertile, retain water and moisture, and facilitate the growth of crops, so that the grain is abundant, and the fruits and vegetables are lush. It is the foundation of people's livelihood and the prosperity of agriculture.
In water conservancy, it is also very useful. It can strengthen dams, make rivers smooth, prevent flooding, and protect the living fields along the coast. And it can dredge the way of water, make the water flow smooth, irrigate the vast land, and moisten the people.
It is indispensable in the business of building houses. 2-% E6% BA% B4 - 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6 can be a cornerstone material, sturdy and durable, carrying buildings, making them stand for a long time, and protecting everyone from wind and rain.
In craftsmanship, it also develops its strength. It can be a material for carving and shaping, and skillful craftsmen can apply their skills according to its texture. It can be turned into exquisite utensils, or decorative products, or practical tools, increasing the elegance of life.
In medicine and pharmacology, it also has wonderful uses. Although it is not the main medicine, it can be adjusted and medicinal properties, assisting other medicines to play an effect, and helping to save lives and wounds.
In war defense, it also has its ability. It can build city barriers, set up checkpoints, keep the enemy outside, protect the peace of the state, and be a barrier for the home country.
It can be seen that 2-% E6% BA% B4 - 5-%E8%8B%AF%E5%9F%BA%E5%90%A1%E5%95%B6 in many fields in the world, have important uses, and are actually indispensable in the world.

There are two baht and five baht today. What is the market value of the artifact?
The price of the artifact, the price of the artifact, is also the measure of the ancient times. The baht is one-twenty-fourth of one tael; the price of the artifact is six baht. Then the price of five baht is five, six, thirty baht. Two baht and five baht, which is thirty-two baht.
The value of the ancient currency varies from time to place. However, if you want to measure its value, you should consider the prices, supply and demand, and the material of coinage at that time.
Looking at the economy of the ancient times, the value of the goods is related to the needs of people's livelihood and the distance between the place of origin. If this artifact is used every day and is well-made, it is not low in If the price of rice at that time was worth a hundred dollars per stone, and one baht of copper could be easily counted. This thirty-two baht artifact, made of copper, could be worth tens or even hundreds of dollars.
If this artifact is a rare item, used unusually, and has complicated craftsmanship, decorated with gold and jade, etc., its value is even more immeasurable, or it can be worth thousands of gold.
If copper was scarce at that time, or if this artifact was unique in shape and had special uses, its price would also rise.
However, the above are all speculative words, and it is difficult to know for sure how much the two baht and five baht artifact was worth in the market at that time. The economy of Gaigu is limited in data and varies widely from place to place, making it difficult to generalize.