What is the synthesis method of pitavastatin calcium intermediate to 5, (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-quinolinyl-vinyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one?

To prepare (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-acetyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one, the synthesis method is quite complicated.

First, suitable starting materials are required, among which key raw materials, such as cyclopropane derivatives containing specific substituents, vinyl acetyl substances with fluorophenyl groups, etc., need to be carefully prepared or purchased from sophisticated reagents.

Second, or by means of various common reactions in organic synthesis. For example, by means of nucleophilic substitution, a cyclopropane derivative containing a suitable leaving group is interacted with a reagent with a specific functional group to introduce a specific substituent. Then a carbon-carbon double bond formation reaction, such as the Wittig reaction or the Heck reaction, is used to construct the desired vinyl structure. The

cyclization step is also key. Or through the nucleophilic addition reaction in the molecule, the specific functional groups in the molecule can interact to form the cyclic structure of pyrone. In this process, the reaction conditions, such as temperature, solvent, catalyst, etc., need to be carefully controlled. If the temperature is too high or too low, the reaction rate or selectivity can be changed; the polarity and solubility of the solvent also have a great influence on the reaction process; and the appropriate catalyst can significantly improve the reaction efficiency and selectivity.

In the synthesis, the control of stereochemistry is particularly important. To obtain a specific configuration of (4R, 6S), or by means of chiral adjuvants, chiral catalysts, etc., it is necessary to guide the reaction to the desired stereochemical direction.

The entire synthesis process requires multiple steps of reaction, and each step requires fine operation and strict monitoring. After ingenious combination and optimization of various steps, the target product can be obtained.

Pitavastatin Calcium Intermediate to 5, (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-quinolinyl-vinyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one What are the Quality Standards

There are now (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-methoxybenzylidene-ethyl] -4-chloro-3,4,5,6-tetrahydro-2H-pyran-2-one, and the intermediate of prazotaxine is 5. Its Quality Standards are as follows:
First words, this material should have specific appearance characteristics such as shape, color and taste, and should be pure and free of variegation and foreign matter. Look at its color, or white as snow, or white-like color, texture or fine powder, tentacles should be dry, no adhesion feeling.
When it comes to identification, it is necessary to follow the method of precision, or by the wonder of infrared spectroscopy, look at its characteristic absorption peak, which is as unique as a fingerprint, to prove its authenticity; or use high performance liquid chromatography to check its retention time, and compare it with the standard product to confirm the authenticity.
When it comes to inspection, the amount of impurities must be strictly limited. The content of each impurity, such as specific organic impurities, must not exceed the specified very small proportion to prevent it from disturbing the purity of the substance. The amount of moisture is also fixed, and it should not be too much, which will cause it to deliquescent and deteriorate, and damage its character. Residual solvents also need to be strictly controlled, and the residues of various organic solvents must not exceed the safety limit to ensure the safety of their use.
Content determination is the most important, and its content should be accurately measured by an accurate method, such as high-performance liquid chromatography. The measured content should be within the specified range to be qualified to ensure the accuracy of the drug and the exact curative effect. These are (4R, 6S, E) - 6 - [2 - cyclopropyl - 4 - (4 - fluorophenyl) - 3 - methoxybenzylidene - ethyl] - 4 - chloro - 3, 4, 5, 6 - tetrahydro - 2H - pyran - 2 - ketone Quality Standards to ensure its quality, effective and safe use.

What are the market application fields of pitavastatin calcium intermediate to 5, (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-quinolinyl-vinyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one?

Today there are (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-ethynyl] -4-methyl-3,4,5,6-tetrahydro-2H-pyran-2-one, and its market application field is quite extensive.

In the field of pharmaceutical research and development, this compound shows unique potential. Because of its specific chemical structure, or can interact with specific biological targets in the human body. Physicians can develop new therapeutic drugs by exploring its binding mode with related receptors and enzymes. For example, for some inflammatory diseases, or according to their structural characteristics, more targeted anti-inflammatory drugs can be optimized to precisely regulate the inflammatory response pathway of the human body, improve the therapeutic effect, and reduce adverse reactions.

There are also promising prospects in the creation of pesticides. Field pests are rampant and endanger crop growth. This compound may have significant biological activity against specific pests, or can interfere with the growth, development and reproduction process of pests, thus achieving the purpose of pest control. For example, a new type of insecticide is designed, which has an efficient killing effect on common crop pests, such as aphids, borers, etc., escorting agricultural harvests, and is more environmentally friendly than traditional pesticides, reducing the negative impact on the ecological environment. < Br >
In the field of materials science, it also has potential. Material developers can use its special structure to introduce it into polymer material systems through chemical modification and other means. It may improve the physical and chemical properties of materials, such as enhancing the stability and flexibility of materials. For example, when preparing high-performance plastics, adding related derivatives of this compound can make plastics maintain better properties under different environmental conditions, expand the application range of materials, and play an important role in many fields such as aerospace, electronics and electrical appliances.

How to control the production cost of pitavastatin calcium intermediate to 5, (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-quinolinyl-vinyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one

In order to obtain (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-ethynyl] -4-methyl-3,4,5,6-tetrahydro-2H-pyran-2-one, the cost of synthesis requires multiple methods and careful management.

Selection of the first raw material. The quality and price of raw materials are related to the fundamental cost. Finding a high-quality and affordable source of 2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-acetylene, and a suitable 4-methyl-3,4,5,6-tetrahydro- 2H-pyran-2-one precursor can reduce the initial expenditure.

The reaction path is also critical. Choose a simple and efficient route to avoid complicated and low-yield processes. If the catalytic reaction is used to promote bonding, the reaction rate and yield are improved, and energy consumption and time cost are reduced. Precise control of reaction conditions, such as temperature, pressure, and catalyst dosage, to ensure that the reaction is carried out efficiently and with less waste of raw materials caused by side reactions.

Optimizing the operation process is also important. In the experimental and production stages, make good use of instruments and equipment to improve operation accuracy and efficiency. Strict quality control, detailed inspection of reaction products at each step, and quick removal of non-compliant products to avoid waste of resources in subsequent steps.

Recovery and reuse cannot be ignored. Reaction by-products and unreacted raw materials, if available, apply appropriate separation and purification methods, recycle into the reaction, increase the utilization rate of raw materials, and reduce the procurement cost of new raw materials.

In summary, controlling the synthesis cost of (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-ethynyl] -4-methyl-3,4,5,6-tetrahydro-2H-pyran-2-one requires careful planning in terms of raw materials, reaction, operation, and recovery to achieve a win-win situation of economy and efficiency.

How to improve the stability of pitavastatin calcium intermediate to 5, (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-quinolinyl-vinyl] -4-hydroxy-3,4,5,6-tetrahydro-2H-pyran-2-one

To improve the stability of (4R, 6S, E) -6- [2-cyclopropyl-4- (4-fluorophenyl) -3-vinyl-ethynyl] -4-methyl-3,4,5,6-tetrahydro-2H-pyran-2-one, you can start from the following ends.

First, it is related to the quality of raw materials. High-purity raw materials need to be selected, because impurities will initiate side reactions in the reaction, which will affect the structure and stability of the product. If the selected raw materials such as cyclopropyl and fluorophenyl must be strictly purified to remove impurities, it is a good choice.

Second, the control of the reaction conditions is crucial. In terms of temperature, this reaction should be maintained within a specific range. If the temperature is too high, the thermal movement of molecules will intensify, or the product will decompose; if the temperature is too low, the reaction rate will be slow, or unstable intermediates will be formed. The pressure is the same, and it is suitable for the pressure to ensure that the reaction proceeds in the direction of generating stable products. And the selection of reaction solvents should not be underestimated. Solvents with good compatibility with reactants and products and no adverse effects on the reaction should be selected to create a stable reaction environment.

Third, the product treatment process is also exquisite. After the reaction is completed, when separating and purifying the product, mild means should be selected. Rough separation, such as high temperature distillation, may damage the stability of the product. After purification, the storage conditions of the product are also critical, and it should be placed in a low temperature, dry and dark place to prevent degradation or deterioration of the product due to temperature, humidity, light and other factors.

Fourth, the method of adding stabilizers can be used. After experimental investigation, substances that can form a stable interaction with the product, such as some compounds with specific functional groups, can be found by adding an appropriate amount, or can significantly improve the stability of the product.

In this way, starting from the aspects of raw materials, reactions, treatments and additives, the stability of the substance may be effectively improved.