3-bromo-pyrazine-2-amine

3 - Mercury, that is, mercury, is a liquid metal, also known as "beauty" in ancient times. Mercury has unique physical properties. It is liquid at room temperature and pressure, like smart water, but it has a metallic luster, shining like flowing silver, which makes it different from many common substances. Its melting point is extremely low, only -38.87 ° C, which means that it can still remain liquid in most cold environments. The boiling point is relatively high, 356.6 ° C. It requires a higher temperature to boil and convert into a gas state.
The density of mercury is extremely high, up to 13.59 grams per cubic centimeter, far exceeding that of common liquids. If compared with water, the mass of mercury in the same volume is about 13.6 times that of water. Holding a container containing mercury can clearly sense its heaviness. Moreover, mercury has good electrical conductivity, like other metals, it can allow electric current to pass smoothly, and has specific applications in the field of electricity.
Mercury is also highly volatile, even at room temperature, it will slowly evaporate to form mercury vapor. This property is extremely dangerous, because mercury vapor is toxic, and when inhaled by the human body, it can cause serious damage to the nervous system, kidneys, etc. Furthermore, mercury can dissolve a variety of metals to form amalgam, and metals such as gold and silver can react with mercury. Amalgam is used in some metallurgical and chemical processes, but at the same time, due to the fact that mercury is easy to combine with other metals, if it is not handled properly, it will cause the metal to be contaminated by mercury and affect the original properties of the metal.

3 - Borax, its chemical properties are as follows:
Borax, scientific name sodium tetraborate, molecular formula is $Na_2B_4O_7\ cdot10H_2O $. Its cold, sweet and salty, belongs to the lung and stomach meridians.
Borax can be slowly weathered in air. When heated to 350 dollars - 400 ^ {\ circ} C $, it will lose all crystal water and become anhydrous borax. Anhydrous borax is white powder with a density of $2.367g/cm ^ 3 $, a melting point of 741 dollars ^ {\ circ} C $, and a boiling point of 1575 dollars ^ {\ circ} C $.
Borax is easily soluble in water, and its aqueous solution is alkaline. The boric acid produced by the hydrolysis of borax is a weak acid, and the hydrolysis of borax will increase the concentration of hydroxide ions in the solution, so that the solution is alkaline. The hydrolysis reaction formula is: $B_4O_7 ^ {2 - } + 7H_2O\ rightleftharpoons 4H_3BO_3 + 2 OH ^ - $ 。
Borax can react with acids, such as hydrochloric acid to produce boric acid and sodium chloride. The chemical equation is: $Na_2B_4O_7 + 2HCl + 5H_2O = 4H_3BO_3 + 2NaCl $.
Borax can dissolve some metal oxides in the molten state, and will show a characteristic color depending on the metal. This property is often used in borax bead test to identify metal ions. For example, when co-melting with cobalt oxides, blue cobalt metaborate will be formed.
Borax can also undergo complexation reactions under certain conditions. Borate ions can react with polyhydroxy compounds (such as glycerol) to form complexing acids, thereby enhancing the acidity of the solution.

The synthesis method of 3-propyl-2-ketone is very common, and it is now known in ancient Chinese.
First, ethyl propionate is used to start with ethyl propionate, followed by ethanol and alcohol. Claisen method. Among them, ethyl propionate is catalyzed by ethanol. Under the catalysis of ethanol, the molecules interact with each other, crack and recombine, and produce 3-propyl-2-ketone precursor. Then, the appropriate hydrolysis and acidification steps can be taken to obtain the target. The reverse principle is based on the combination characteristics of esters in the context of different properties, which is commonly used in the synthesis.
Second, acetone is used as a raw material to first catalyze the activation of acetone molecules, and then formaldehyde is introduced. The active site of acetone is the addition of formaldehyde, which forms the intermediate compound, and then the original compound is reduced to 3-propyl-2-one. In this way, the activity of acetone and the low performance of formaldehyde are used to cleverly build the carbon framework of the molecule.
Third, with the starting material of acronaldehyde, ethanol is first generated to react and generate enol ether derivatives. This derivative is then catalyzed by hydrolysis of carbon-carbon and aldehyde groups, so that the ether can be cracked to obtain 3-propyl-2-one. This method makes good use of the incompatibility of acronaldehyde and the inverse activity of aldehyde groups to synthesize. The
method has its own characteristics. In the synthesis, it is necessary to take advantage of the availability of raw materials, cost, and the ease of control of the reaction parts. Only by taking good care of them can an efficient and effective synthesis strategy be obtained.

3 - Toad puff is a treasure of traditional Chinese medicine, its application is quite extensive, and it has extraordinary uses in many fields.
In the field of medicine, toad puff has significant medicinal effects. "Compendium of Materia Medica" contains: "Toad enters the Yangming Meridian, reduces virtual heat, performs moisture, kills insects, and requires medicine for chancre, carbuncle, and various sores." Toad puff tastes refreshing, has a warm nature, is poisonous, and returns to the heart meridian. It has the effect of detoxifying, relieving pain, and awakening the mind. It can treat carbunx, scrofula, sore throat, toothache, etc. Such as Liushen Pills, which contain toad puff ingredients, and are effective in treating sore throat, single and double moths, etc. External use can make the swelling and poison dissipate, and internal use can open up the filth and wake up the nerves, and treat acute diseases such as heat stroke, dizziness, swelling, abdominal pain and vomiting.
In terms of health care, although toad crisp is toxic, it needs to be used with caution, but after reasonable processing and compatibility, it may be beneficial for some constitutions. However, non-professionals should never use it by themselves to avoid poisoning.
In ancient alchemy and other secret recipes, there are also occasional toad crisp figures. The ancients believed that it had special spirituality and efficacy, or was used to refine medicinal pills for the pursuit of longevity and other purposes. Although from the perspective of modern science, such practices may have no scientific basis, but they reflect their unique position in the cognition of the ancients.
Toad cake plays an important role in traditional Chinese medicine and some ancient cultural practices. However, due to its toxicity, professional guidance must be followed when using it to ensure safety and effectiveness.

Looking at the city of Banxia, its situation is also very impressive. In today's world, Banxia is quite popular in the field of medicine, and its market situation is booming.
Because Banxia has the power of dryness and dampness to reduce phlegm, reduce inversion and prevent vomiting, eliminate ruffians and disperse knots, and is effective in the treatment of many diseases. Therefore, doctors like to use it more, which is one of the major reasons for its strong market demand.
Looking at it in its own production area, it is planted everywhere. However, due to differences in regions, climates and soils, its quality is also uneven. High-quality Banxia is expensive and popular in the market. Farmers in the production area see that Banxia is profitable, and there are many ways to expand seeds.
As for the trade between businesses, there are frequent transactions. Pharmaceutical merchants exchange, or seek high-quality goods to supply large hospitals and pharmaceutical companies; or find those with suitable prices to meet the needs of ordinary pharmacies. However, there are also shoddy and mixed-eyed people who want to make huge profits, which is the harm of the market.
Looking at its price trend, in recent years, due to the intertwining of various factors, it fluctuates from time to time. On the one hand, the cost of manpower and agricultural materials has risen, resulting in an increase in planting costs, and prices have a tendency to rise; on the other hand, the market competition is fierce, and the output of some producing areas has surged, causing prices to occasionally fall.
Overall, although the market prospect of Banxia is quite broad due to the support of medical demand, it also requires the joint efforts of all parties to standardize planting and strictly control circulation in order to achieve long-term and orderly development, so as to ensure that this good medicine persists in the market and benefits all people.