(-)-2,3,5,6-Tetrahydro-6-phenylimidazo(2,1-b)thiazole phosphate

"Tiangong Kaiwu" is a scientific and technological masterpiece written by Song Yingxing in the Ming Dynasty. However, what you asked about involves the expression of chemical structure, which contains many garbled characters, and it is difficult to clarify exactly what it refers to, so it is difficult to answer accurately in ancient classical Chinese. However, I will try my best to solve it according to reasonable speculation.
If the question is about the chemical structure of a substance containing a specific combination of elements, the ancient chemical cognition did not have the precise structural cognition system as it is today. Ancient chemistry mostly focuses on the phenomenon of material change and simple application.
The ancients recognized substances by their appearance, properties, and sources. For example, metals, such as gold, silver, copper, iron, etc., are observed for their color, hardness, ductility and other characteristics; for compounds, such as table salt, it is known that their salty taste can be seasoned and preservative, but they do not know the precise chemical structure of their sodium chloride.
If it is speculated that the structure of an organic compound containing carbon, hydrogen, oxygen and other elements is inferred, although the ancients did not know the modern structure theory, they also had a lot of practice in organic substances. For example, wine is known to be obtained by fermentation of grains, and it is also known that wine has irritating odor and intoxicating properties.
Although ancient chemistry has not reached the depth of today's microstructure cognition, its accumulated practical experience lays the foundation for the development of later chemistry. If you can clarify the exact matter you are asking about, I will try my best to answer it in a more ancient language.

"Tiangong Kaiwu" cloud: saltpeter, its color ribbon yellow, bitter taste, can be dissolved in water, heated to sublimate into gas, this is its significant physical properties.
Saltpeter tastes hard, cold and toxic. It can be dissolved in water. When it dissolves, the water temperature drops slightly, which is its dissolution characteristic. Furthermore, heating saltpeter will sublimate into gas, and this sublimation is also one of its physical characteristics.
As for the expressions "2,3,5,6-tetraamino-6-benzylamino-2,1-b" mentioned in the text, it is difficult to know exactly what they refer to. It seems that it is not a common thing involved in "Tiangong Kaiwu", or a specific name for modern chemistry. However, from the perspective of the ancient book "Tiangong Kaiwu", it is difficult to describe the exact physical properties. Saltpeter was mostly used in alchemy and gunpowder in ancient times, and its physical properties were also crucial in the application at that time, such as using its heating and sublimation properties to separate and purify, and using its solubility to distinguish it from other things.

"Tiangong Kaiwu" is a great scientific and technological work in our country in ancient times. However, the expression of this question asked by Jun is quite confusing, and it is difficult to understand its true meaning. There seem to be many symbols and words with unclear meanings mixed in, and it is difficult to directly know what the "2,1-b" refers to, and I do not know the exact meaning of “+-”“-% E5% 9B% 9B% E6% B0% A2 ". If you can restate this question in clear and unambiguous terms, explaining the specific substances, reactions, etc. involved in "2,1-b", as well as the specific questions about "2,3,5,6-tetracyano- 6-benzylpyridine base (2,1-b) ", such as its use in a specific field, whether it is in medicine, chemical or other, I will use the perspective of "Tiangong Kaiwu", in the form of classical Chinese, to explain in detail, in order to help you as much as I can.

In the era covered by "Tiangong Kaiwu", the synthesis of benzyl benzoate required ingenious methods. The synthesis of this ester often uses benzoic acid and benzyl alcohol as raw materials and goes through the process of esterification.
To make benzoic acid, it can be obtained by oxidation of toluene. In the past, or by chemical oxidation, such as using a specific oxidant, at a suitable temperature and pressure, toluene was gradually converted into benzoic acid. Toluene is placed in a special container, added with a selected oxidant, heated slowly, and the reaction process is carefully observed. Temperature control is very important. If it is too high, there will be many side reactions, and if it is too low, the reaction will be slow.
As for benzyl alcohol, there is also a way to prepare it. Or extract from natural things, or by chemical synthesis. If extracted from natural, you can choose plants rich in benzyl alcohol, which can be obtained by distillation, extraction, etc. If chemically synthesized, it is often obtained by hydrolysis of the corresponding halobenzyl. Co-placing halobenzyl with an appropriate amount of alkali solution, heating and stirring, the halogen atom is gradually replaced by hydroxyl groups to form benzyl alcohol.
When both benzoic acid and benzyl alcohol are prepared, the esterification reaction is carried out. Mix the two in an appropriate ratio and add a catalyst, which may be sulfuric acid, etc. Under heating and stirring, the carboxyl group of benzoic acid and the hydroxyl group of benzyl alcohol are dehydrated and condensed to form 2,1-benzyl benzoate esters. During the reaction, in order to promote the right shift of equilibrium, or to remove water by means of water removal, such as a water separator. After the reaction is completed, through the steps of separation and purification, pure 2,1-benzyl benzoate can be obtained. First, the unreacted raw materials and low-boiling impurities are removed by distillation, and then the high-boiling impurities are removed by recrystallization, and the final refined product is obtained.

Today, there are （+-） - 2,3,5,6 of the four things, and - 6 of the naphthyl pyridine, and (2,1 - b) of cobalt pyridyl carboxylate in the market application status? Let me know in detail.
（+-） - 2,3,5,6 of the things, in various fields have their uses. In the chemical synthesis process, or as a key raw material, to help many reactions proceed smoothly, such as building a delicate molecular structure to form the required compounds, just like a skilled craftsman according to the plan to make the reaction according to the established track.
And -6 naphthyl pyridine has made a lot of contributions to the field of scientific research. In the path of drug research and development, it may be used as a lead compound to guide the way for the creation of new drugs. Like a guiding light, in the vast ocean of pharmacy, it points the way for the ship of exploring new drugs, and helps researchers find a cure and save people.
As for (2,1-b) cobalt pyridine carboxylate, it has made a name for itself in the field of industrial catalysis. It can speed up the reaction rate and improve the efficiency of production, just like adding a strong engine to the car of industrial production, making the production process smoother and more efficient. In the market, because of its unique effect, it is favored by many enterprises and is widely used in related production links to promote the development of the industry.
To sum up, this number has its own place in the market, shining in different fields, and has a profound impact on the progress of related industries.