5-bromo-1H-pyrazolo[3,4-b]pyridine-3-carboxylic acid

From the perspective of "Tiangong Kaiji", alum, especially the alum solution at a concentration of 5-8%, plays a key role in the preparation of 1H-pyrrolido [3,4-b] pyridine-3-carboxylic acids.
Alum mainly plays the role of mordant and catalyst here. In ancient dyeing techniques, alum has long been used as a mordant to better combine dyes with fabrics. In the synthesis of 1H-pyrrolido [3,4-b] pyridine-3-carboxylic acids, alum can change the activity of the reactants, reduce the activation energy required for the reaction, and make the reaction more likely to occur. For example, in some chemical reactions, alum can promote more efficient contact between the molecules of the reactants, accelerate the reaction process, and increase the rate of product formation.
From the perspective of metal ion properties, alum contains metal ions, such as potassium alum containing potassium ions and aluminum ions. These ions can interact with specific groups of the reactants in the reaction system, or change the electron cloud distribution of the reactants, helping to form and break chemical bonds. For example, metal ions can bind to atoms containing lone pairs of electrons in the reactants, making the reactants more prone to react, which in turn guides the reaction towards the formation of 1H-pyrrolido [3,4-b] pyridine-3-carboxylic acids.
In addition, alum may also regulate the pH of the reaction system. In some organic synthesis reactions, pH has a great influence on the reaction process and product selectivity. Hydrolysis of metal ions in alum can change the pH of the system and create an environment suitable for the formation of 1H-pyrrolido [3,4-b] pyridine-3-carboxylic acid. Like under specific reaction conditions, suitable pH can inhibit the occurrence of side reactions and improve the purity and yield of the target product.

To prepare 5-hydroxy-1H-pyrazolo [3,4-b] pyridine-3-carboxylic acid, there are many synthesis methods, which are described in detail as follows:
First, suitable pyridine derivatives are used as starting materials. First, a specific position of the pyridine ring is halogenated, and a halogen atom is introduced. This step can be achieved by electrophilic substitution reaction. The conditions need to be precisely regulated according to the selected halogenated reagent. Subsequently, the halogenated pyridine derivative and the nitrogen-containing heterocyclic reagent undergo nucleophilic substitution reaction under base catalysis to construct the pyridazolo [3,4-b] pyridine skeleton. Next, the obtained skeleton is modified by hydroxylation, which can be attacked by suitable nucleophiles and substituted for the corresponding groups to introduce hydroxyl groups. Finally, through carboxylation, carboxyl groups are introduced at designated positions, such as using specific carboxylation reagents and reacting in a suitable temperature and solvent to obtain the target product.
Second, starting from pyrazole derivatives. The pyrazole ring is modified, and through a series of reactions, such as alkylation, acylation, etc., suitable substituents are introduced at specific positions to prepare for connection with the pyridine ring. Afterwards, cyclization reactions are carried out with pyridine-related fragments to form a pyrazolo [3,4-b] pyridine structure. Then the structure is introduced into the hydroxyl group and the carboxyl group. The hydroxyl group can be introduced or oxidized, and the carboxyl group introduction is selected according to the specific situation. The target molecule is obtained.
Third, the "one-pot method" strategy is adopted. Select the raw materials that can simultaneously construct the skeleton of pyrazolo [3,4-b] pyridine and introduce the hydroxyl and carboxyl groups. In the same reaction system, through reasonable regulation of the reaction conditions, such as temperature, pH, catalyst type and dosage, etc., so that each step of the reaction can proceed in sequence without separating the intermediate product. One-step synthesis of the target 5-hydroxy-1H-pyrazolo [3,4-b] pyridine-3-carboxylic acid. This strategy is easy to operate, can reduce the loss of intermediate steps, and improve the yield, but it requires strict control of the reaction conditions.

The physical properties of 3-carboxyl-1H-pyrazolo [3,4-b] pyridine are as follows:
This compound is mostly solid under normal conditions. Its solubility is not important for determination. Generally speaking, it has a specific melting property, and it can be preliminarily judged for its solubility. If the content is small, the melting property is close to the theoretical value reported in this paper; if there are many, the melting property may be reduced and the melting range is low.
Solubility is also an important physical property. It has different phenotypes in different solubility, such as water, and its solubility may be limited. Due to the unique nature of its molecules, its solubility is not high, so it is dissolved in large quantities by the full action of water molecules. However, in some soluble materials such as ethanol and dichloromethane, the solubility may be improved due to the solubility of its molecules, which can form a specific force to promote its dissolution.
In terms of crystal forms, there may be multiple crystal forms, and different crystal forms may have differences in physical properties such as density and hardness. The formation of crystal forms is influenced by the crystalline components, such as the degree of solution, cooling rate, dissolution rate, etc. The difference in the rationality of different crystal forms is, in terms of material quality, or the dissolution rate of the shadow material is bioavailability.
In addition, the density of 3-carboxyl-1H-pyrazolo [3,4-b] pyridine determines the amount of its position. In a specific process, the density is significant in terms of material calculation, mixing uniformity, etc. Its outer layer is often white to white powder or crystal. In addition, it can be used as a preliminary basis. In addition, the multi-physical properties are mutually reinforcing, and the compounds are jointly used in scientific research, engineering, and other fields.

Today, a merchant asked Yu Wu, "What is the market price of boron-1H-directional union [3,4-b] to its-3-carboxylic acid?"
Boron-1H-directional union [3,4-b] to its-3-carboxylic acid is also a chemical substance. Its market price often changes for a variety of reasons, such as the quality of the quality, the situation of supply and demand, the difficulty of production, market competition, etc.
If the quality is high and the market demand is strong, but the production is difficult and there are few competitors, the price will be high. On the contrary, if the quality is average, the supply exceeds the demand, the production is convenient, and the competition is fierce, the price may be low.
However, I do not have the exact market price at the moment. For details, merchants can go to the chemical trading market and consult various suppliers to compare their quotations. Or consult relevant chemical information platforms and industry reports to get the latest price quotations. In this way, they can get their more accurate market prices.

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