6-aryl amino pyridone formamide crystal purity via solvent recrystallization
Solution Overview
Problem
The existing 6-arylamino pyridone carboxamide compounds, such as those disclosed in CN102020651A, face challenges in achieving stable and pure crystalline forms crucial for effective drug morphology and processing performance, which are essential for their therapeutic applications, particularly in inhibiting MEK-mediated disorders like inflammatory diseases and cancers.
Innovation Solution
A specific crystal form of the 6-arylamino pyridone carboxamide compound characterized by distinct X-ray powder diffraction peaks and differential scanning calorimetry (DSC) thermogram profiles is developed, along with a preparation method involving dissolution in an aprotic polar solvent, followed by solvent addition, crystallization, filtration, and drying, to produce a high-purity crystalline composition suitable for pharmaceutical use.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If silica gel flash column chromatography is used to prepare the compound, then the compound can be obtained, but the manufacturing precision and purity of the crystalline form are insufficient
Solution Approach 1:
The patent applies parameter changes by optimizing crystallization conditions including solvent selection (acetonitrile, ethanol, water mixtures), temperature control (cooling from room temperature to 4°C), and pH adjustment (adding ammonium hydroxide to reach pH 7-8). These parameter modifications enable the formation of stable crystalline forms with defined XRD patterns and high purity, resolving the contradiction between manufacturing precision and ease of manufacture.
Solution Approach 2:
The patent utilizes phase transitions during the crystallization process. The compound transitions from dissolved state in warm solvent to crystalline solid upon cooling and solvent addition. This controlled phase transition enables the formation of stable polymorphic forms with specific XRD characteristics, achieving high purity crystalline products while maintaining practical manufacturability.
2Reliability
If stable and pure crystalline forms are achieved, then drug morphology and processing performance are improved, but the preparation process becomes more complex
Solution Approach 1:
The patent applies preliminary action by performing pH adjustment and solvent optimization before the crystallization step. Ammonium hydroxide is added beforehand to establish the correct pH range (7-8), and the solvent system is pre-prepared with specific ratios of acetonitrile, ethanol, and water. This preliminary preparation simplifies the overall process by ensuring optimal conditions are in place before crystallization begins, reducing the need for complex post-processing steps.
Solution Approach 2:
The patent uses solvent mixtures as intermediaries to facilitate crystallization. The combination of acetonitrile, ethanol, and water acts as an intermediary medium that controls solubility and promotes stable crystal formation. This intermediary solvent system mediates between the compound and the crystallization conditions, enabling reliable crystal formation while keeping the process straightforward.
3Manufacturing precision
If multiple crystallization parameters are optimized, then crystal purity and stability are enhanced, but the production time increases
Solution Approach 1:
The patent applies periodic action through the controlled cooling process and staged solvent addition. The crystallization occurs in periods: initial dissolution at room temperature, followed by controlled cooling to 4°C, then staged addition of anti-solvent (water or ethanol). This periodic approach allows crystals to form and grow in controlled stages, achieving high purity without requiring excessively long processing times at each stage.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method yields a crystal with high purity and stability, facilitating improved manufacturing and storage of medicaments, and is beneficial for industrial production, ensuring effective inhibition of MEK enzyme and treatment of related disorders.
Implementation Method 1
dissolving a crude compound of formula (I) in an aprotic polar solvent at a temperature of 80 °C - 120 °C; lowering the temperature; adding a second solvent; crystallizing
Implementation Method 2
characterized by diffraction peaks expressed by 2θ values at 7.86°, 19.09°, 21.80 °, 23.87°, 26.00°, and 28.12° in an X-ray powder diffraction spectrum
Implementation Method 3
characterized by a differential scanning calorimetry (DSC) thermogram having an absorption peak at about 202.2 °C
Data Source
Figure 1~2
AI summary
Provided are 6-aryl amino pyridone formamide compound crystal and a preparation method therefor. In the present invention, 6-(2-chlorine-4-iodopheny amino)-N-(2-hydroxyl ethyoxyl)-5-methyl-4-oxo-4,5-dihydrofuran[3,2-c]pyridine-7-formamide is dissolved in a polar aprotic solvent, a second solvent is added for recrystallization, and a crystal is obtained. The crystallization method is simple to operate and conducive for industrial production. The produced crystal has high purity, good stability, and is conductive for pharmaceutical production and storage.