5-bromo-3-cyanopyridine

Mercury is a highly toxic substance. In ancient times, mercury and alchemy (mercury sulfide) were commonly used in alchemy, medicine, funerals, and handicraft production.
First, the field of alchemy. The ancients believed that the elixir of immortality could be obtained through alchemy, and mercury was often used in the process of alchemy because of its unique chemical properties. Many alchemists regarded mercury as the key ingredient in refining miraculous pills, hoping that through complex refining processes, mercury could be converted into an elixir that could prolong life, strengthen the body, and even make people soar into immortals. For example, Ge Hong's "Baopuzi Neibu" has many records on alchemy, among which the use of mercury is many examples.
Second, medical use. Some ancient physicians believed that mercury and mercury-containing compounds had certain medicinal effects. For example, mercury can be used to treat skin diseases such as scabies and sores. The medicinal records of mercury in the "Compendium of Materia Medica" call it "the main scabies, fistulae, scabs, ulcers, white baldness, killing lice in the skin, abortion, heat removal, killing gold, silver, copper, tin poison". However, due to the toxicity of mercury, improper use can easily lead to poisoning, so it is rather cautious when applying.
Third, funeral etiquette. Mercury has unique uses in funerals, the most typical of which is the Mausoleum of Qin Shi Huang. According to the "Historical Records · Qin Shi Huang Benji", "Mercury is used as a hundred rivers and seas, and the mechanism is instilled, with astronomy on the top and geography on the bottom". Mercury is widely used in mausoleums to simulate rivers, lakes and seas. On the one hand, it creates a grand and mysterious underground world, showing the majesty of the emperor; on the other hand, the toxicity of mercury can prevent the mausoleum from being stolen and protect the safety of the mausoleum.
Fourth, the production of handicrafts. Mercury can form amalgam with a variety of metals, and the ancients used this property to make gilt utensils. First, gold and mercury are made into gold amalgam, which is applied to the surface of the utensils. Heating evaporates the mercury, and the gold is attached to the utensils to form exquisite gilt decorations, such as the gilt process on many ancient bronzes and gold and silver

To prepare 5-hydroxyl-3-aminopyridine, there are many methods of synthesis, each with its own advantages. This is what you describe.
One is to use pyridine as the initial raw material, nitrate to obtain nitropyridine, and then use a suitable reducing agent, such as iron filings and hydrochloric acid system, to reduce the nitro group to an amino group to obtain aminopyridine. Subsequently, under specific conditions, the hydroxylation reaction is carried out, and the hydroxyl group is introduced to obtain the target product. In this process, the nitration step needs to pay attention to the control of the reaction conditions. The temperature and the proportion of reagents are all related to the purity and yield of the product. When hydroxylating, it is crucial to choose the appropriate hydroxylation reagent and reaction environment.
The second can be spliced from compounds containing corresponding substituents by multi-step reactions. For example, choose an aromatic ring compound with suitable substituents, and form a pyridine ring through cyclization reaction, while introducing amino and hydroxyl groups in appropriate positions. This approach requires fine design of the reaction route, and the order and conditions of each step of the reaction are extremely critical. During cyclization, the choice of catalyst and the consideration of the reaction solvent have a profound impact on the reaction process and product structure.
The third is biosynthesis. With the help of specific microorganisms or enzymes, 5-hydroxy- 3-aminopyridine is synthesized through a metabolic pathway in vivo with simple compounds as substrates. This method is green and environmentally friendly, and the conditions are mild, but the requirements for the biological system are quite high. It is necessary to screen out efficient microorganisms or enzymes, and strictly control the culture conditions, substrate concentration and other factors to achieve higher yields.
The fourth is the coupling reaction using metal catalysis. Halogenated pyridine derivatives are used as raw materials, and reagents containing amino and hydroxyl groups are coupled to synthesize the target product under the action of metal catalysts such as palladium catalysts. In this process, the activity of metal catalysts, the selection of ligands, and the pH regulation of the reaction system are all key factors affecting the success or failure of the reaction and the efficiency.

Mercury is a highly toxic substance with unique properties and many physical properties. Under normal conditions, mercury is a liquid metal, which is like silver like water and does not flow. Its appearance is as bright as a mirror, shining with a unique luster.
The melting point of mercury is extremely low, about -38.87 ° C, so it is liquid at room temperature, which is quite rare among metals. And its boiling point is not high, about 356.6 ° C. Due to its melting point and boiling point, mercury is easily vaporized when heated and turns into mercury vapor. This vapor is colorless and odorless, but highly toxic. If inhaled into the human body, it will seriously harm health.
The density of mercury is extremely high, reaching 13.59g/cm3. Compared with common metals, such as water, the density of mercury is only 1g/cm3. The density of mercury far exceeds that. When placed in water, it sinks to the bottom immediately. Mercury has good electrical conductivity, which is the same as that of most metals, and can conduct current in circuits.
The surface tension of mercury is quite large. If dropped on a plane, mercury drips together but does not disperse. It is bead-like, like a mercury pearl, and rolls freely. And mercury and most metals can form amalgam, which is a special property of mercury. When amalgam is formed, or accompanied by volume changes, this property is widely used in metallurgy and other fields.
However, it is necessary to keep in mind that mercury is highly toxic. When using and disposing of it, it is necessary to exercise caution and adhere to safety procedures to avoid mercury leakage, in order to prevent endangering life and the environment.

In today's market, the prices of mercury and aminopyridine vary according to their quality, quantity, and market conditions.
Mercury is a common chemical product, but it is also highly toxic. It is mostly in bottles, and the price varies depending on the quantity. In ordinary chemical and industrial markets, industrial mercury, if it is of high purity and abundant quantity, may cost between hundreds of gold and thousands of gold per bottle. However, due to stricter control, coupled with production and transportation costs, its price may fluctuate. Illegal access to mercury, the price may change, but it is prohibited by law, and the risk is huge.
Aminopyridine, also a genus of chemical raw materials, has a variety of variants and uses. It is widely used in the fields of medicine and material synthesis. If it is ordinary industrial grade aminopyridine, depending on the purity, the price per kilogram may range from tens of gold to hundreds of gold. If it is high purity, it is suitable for fine chemical and pharmaceutical R & D, and the price is higher, per kilogram or more than a thousand gold. And its price often changes with market supply and demand. If there are many people at a time, but the production is insufficient, the price will rise; conversely, if the supply exceeds demand, the price may drop.
View the market price of the two, both are subject to various factors, such as policy, cost, supply and demand, so if you want to know the real-time price, you should consult chemical companies and market brokers to get the exact number.

Mercury is a commonly used item in alchemy cultivation. It is necessary to pay more attention to things during the process of storage, and it cannot be ignored.
Mercury is easy to lose in its sexual flow, and it is stored in a dense device. If it is placed in an ordinary container, mercury will easily escape in the air. It is poisonous, and if people inhale it, they will be damaged. Therefore, the mercury device must be dense to prevent it from leaking. And it should be placed in a place where it is hidden, to avoid height. Because of the high temperature, the mercury will accelerate, and the situation will increase sharply.
The mercury is sent, and the person who sends it should be extra careful. The road you travel is to avoid people and dense. Be careful to avoid collisions on the way. If the container is broken, the mercury will come out, and it will not spiral. And there are urgent things, such as sulfur. Once the mercury is destroyed, it will be covered with sulfur quickly, so that the mercury sulfide will be dissolved and its toxicity will be reduced.
It is not as easy to be destroyed as mercury, but it is also toxic. To store it, you also need to be in a dry place to prevent it from growing and rotting. Because of its rotten things, it may also be harmful.
In the same way, it is necessary to prevent collisions. And do not mix with food and other things, so as not to pollute and harm others.
In other words, mercury is a dangerous thing, and it is necessary to be cautious when storing it or not. The person who manages it must have the knowledge and skills of the warehouse, and follow the rules to ensure the safety. No, once it is lost, it will be too late to regret.