5-bromo-3-iodo-2-aminopyridine

The main user of the amino group is related to the foundation of biochemistry, and it is very powerful in all kinds of life energy.
The amino group is the building group of the protein. Proteins, the main organ of life, are also indispensable in the structure, metabolism and immunity of the body. And the amino group is connected with peptide bonds to form a chain of peptides, which are twisted and folded, and have a specific shape and energy. If the protein of the muscle gives the body movement; if the protein of the antibody protects the body from security, all lysine groups are formed.
And amino groups are also important in the way of metabolism. It can be involved in the circulation of nitrogen, through the reactions of deamination and transamination, or to form sugar and fat to store energy, or to excrete urea. Such as the change of amino groups in the liver, regulating the level of blood ammonia, and protecting the body.
Furthermore, amino groups also have their functions in the domain of nerve conduction. Such as glutamic acid, gamma-aminobutyric acid, etc., are neurotransmitters, which are responsible for the delivery of nerve signals and are related to cognition, emotion, and memory. If it is out of balance, various nerve diseases may occur.
And in the growth and differentiation of cells, amino groups also help. It provides materials for the synthesis of nucleic acids and coenzymes, promotes the proliferation and maturation of cells, and has great contributions to the education of embryos and the restoration of tissues.
Amino, in the process of biochemistry, if the cardinal wants, in all kinds of functions of life, are the foundation, maintaining the stability of life, indispensable.

There are many synthesis methods of aminopyridine, each with its own advantages and disadvantages. In the context of "Tiangong Kaiji", the following are common synthesis methods:
First, using pyridine as the starting material, nitropyridine can be obtained by nitrification, and then by reduction means, such as iron powder, hydrochloric acid or catalytic hydrogenation, the nitro group is converted into an amine group. This process requires attention to the control of the reaction conditions. Temperature, pressure and catalyst selection will all affect the reaction yield and selectivity. For example, when catalyzing hydrogenation, suitable catalysts such as palladium carbon can be controlled at a certain temperature, which can improve the reaction efficiency.
Second, the nucleophilic substitution reaction of halogenated pyridine with ammonia or amine compounds can be used. Halogen atoms in halopyridine are highly active and can undergo nucleophilic substitution with ammonia or amine to form aminopyridine. In this reaction, the choice of solvent is quite critical, and polar solvents can often promote the reaction. For example, using ethanol as a solvent, under heating conditions, halopyridine reacts with ammonia to obtain aminopyridine. However, it is necessary to pay attention to the difference in the activity of halopyridine. The reactivity of different halogen atoms is different, and the reaction conditions need to be adjusted accordingly.
Third, the rearrangement reaction of pyridine derivatives is used. Some pyridine derivatives can be rearranged under specific conditions to form aminopyridine. This method requires specific reaction reagents and conditions. For example, under the action of acidic or basic catalysts, pyridine derivatives with specific structures undergo rearrangement reactions to realize the migration of functional groups and generate aminopyridine. However, such reactions require strict substrate structures, and precise design of substrate molecular structures is required to achieve smooth reactions.

Amine groups are nitrogen-containing functional groups in organic compounds, which have many unique physical properties.
Amine compounds interact with water molecules through hydrogen bonds due to the presence of lone pairs of electrons on nitrogen atoms, so lower amines are usually soluble in water. Like methylamine and dimethylamine, they are gases at room temperature and pressure, while trimethylamine is also a gas at room temperature, but more advanced amines such as ethylamine are liquids. Moreover, as the number of carbon atoms in the amine molecule increases, its water solubility will gradually decrease. This is due to the growth of carbon chains, the non-polarity of the molecule is enhanced, and the interaction with water, a polar solvent, becomes weaker.
In terms of boiling point, the boiling point of amines is closely related to the intermolecular forces. Due to the formation of hydrogen bonds between amines, the boiling point is relatively high. However, compared with alcohols, the strength of hydrogen bonds between amines is weaker, because the electronegativity of nitrogen atoms is less than that of oxygen atoms, so the boiling point of amines is generally lower than that of alcohols with similar molecular weights. For example, the boiling point of ethylamine is lower than that of ethanol.
On the odor, lower-grade amines often have a pungent smell, such as methylamine with a pungent smell similar to ammonia, while the smell of higher amines is relatively weak, and some higher-grade fatty amines even have a weak fragrance.
On the density, the density of fatty amines is usually less than that of water and will float on the water surface, while the density of some aromatic amines is greater than that of water. In addition to their performance in water, amine compounds are generally soluble in organic solvents, such as ethanol, ether, etc. This is because they have certain organic groups and have similar structural characteristics to organic solvents, following the principle of "similar miscibility".

In today's world, what is the price of serotonin and dopamine medicine in the market? I should say it in detail for you in quaint and elegant words.
A serotonin conditioner is mostly used to treat emotional diseases, such as depression and anxiety. The price also varies depending on the brand of the drug, the process of making it, and the place where it is sold. Among the drug shops in the market, if the drug is a capsule or tablet, the price of a box may range from tens to hundreds of dollars. If it is an imported famous drug with exquisite craftsmanship and outstanding efficacy, the price is even higher, or to three or four hundred dollars a box. And domestic products, because the cost is slightly lower, the price may be around a hundred dollars, and there are also high-quality and cheap ones, only a few dozen dollars.
As for dopamine medicine, it is mostly used to treat neurological and cardiovascular diseases. It is an injection agent, and the price is different. In a hospital pharmacy, the price of a small bottle is ordinary or twenty or thirty dollars. If it is a special refined product, used for the treatment of severe diseases, the price can be doubled, or even fifty or sixty dollars a bottle. However, in different hospitals, because of their different procurement routes and operating costs, the price fluctuates.
Although the price of such drugs in the city fluctuates, it depends on the reason of supply and demand and the number of costs. Those who buy medicine should carefully observe the quality and pay attention to the price. They should not just ask for a low price and ignore the efficacy of the medicine, nor should they blindly pursue the expensive and spend money. Always take the cure of diseases as the key, and choose the one with excellent cost performance and use it.

"Tiangong Kaiwu" says: "Where gunpowder is, saltpeter and sulfur are the main ones, supplemented by grass and wood ash. The nitrate is to yin, and the sulfur is to yang. The two gods of yin and yang meet in a seamless and tolerable way. When it comes out, the characters are taken by it, and the soul is scattered and the soul is powder."
Regarding the storage conditions of gunpowder, it is quite particular. First, it needs to be placed in a dry place. The saltpeter and other ingredients in gunpowder are easy to absorb moisture. If the storage environment is humid, after the saltpeter absorbs moisture, it will cause the properties of gunpowder to change, reduce its explosive performance, and even cannot be used. In case of continuous rainy season, if the place where the gunpowder is stored fails to keep it dry, it will be susceptible to moisture failure.
Second, keep away from the source of fire. Gunpowder is extremely flammable and explodes If a spark splashes on it, it will cause intense combustion or even explosion in an instant, which is powerful enough to destroy things and hurt people. Therefore, where gunpowder is stored, fireworks must be strictly prohibited, and there should be no open flames or hot topics around.
Third, it should be placed in a cool place. High temperature will change the activity of gunpowder's internal components, accelerate its chemical reaction, and increase the risk of spontaneous combustion and spontaneous explosion. If the summer is hot, if the gunpowder is placed under the hot sun or in a place with high temperature, it is tantamount to planting hidden dangers.
Fourth, the storage place should be well ventilated. Good ventilation can avoid the accumulation of gas emitted by gunpowder, prevent accidents caused by high gas concentration, and keep the air in the storage environment fresh and dry, which is conducive to the long-term storage of gunpowder.
In this way, follow the conditions of dryness, fire avoidance, shade, and ventilation, so that the gunpowder can be properly stored and its performance is stable, so that it can function normally when needed.