N-Acetylcysteine Amide Synthesis Impurity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for synthesizing N-acetylcysteine amide (NACA) result in excessive levels of di-NACA impurities, which are not acceptable to regulatory agencies, and require chromatographic purification, making the process inefficient and unsuitable for large-scale production.
Innovation Solution
A method involving the reaction of cystine with methanol and a chlorinating reagent to form cystine dimethylester dihydrochloride, followed by conversion with triethylamine and acetonitrile to form di-N-acetylcystine dimethylester, and subsequent reduction with ammonium hydroxide to produce NACA, which includes specific impurities B1 and B2 as markers for the synthetic process, eliminating the need for chromatographic purification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional NACA synthesis methods are used, then NACA can be produced, but excessive diNACA impurities (4-5%) are generated that are not acceptable to regulatory agencies
Solution Approach 1:
The patent changes the synthesis pathway parameters by using a multi-step process involving cystine dimethylester dihydrochloride formation, conversion to di-N-acetylcystine dimethylester, and subsequent reduction. This parameter change in the synthesis route fundamentally alters the impurity profile, eliminating excessive diNACA formation while maintaining NACA production efficiency.
Solution Approach 2:
The patent extracts and removes the problematic diNACA impurity formation pathway by using a refined synthesis method that prevents its generation in the first place. The process selectively produces NACA while leaving behind minimal diNACA, effectively extracting the harmful impurity from the product stream.
2Manufacturing precision
If chromatographic purification is used to reduce diNACA content, then NACA purity increases, but the process becomes inefficient and unsuitable for large-scale production
Solution Approach 1:
The patent applies preliminary action by designing a synthesis pathway that prevents diNACA impurity formation from the outset, rather than requiring subsequent purification steps. The synthesis method is optimized in advance to deliver high-purity NACA directly, eliminating the need for chromatographic purification and enabling scalable production.
3Manufacturing precision
If chromatographic purification is implemented, then diNACA impurity levels decrease, but the manufacturing process complexity and cost increase
Solution Approach 1:
The patent extracts the purification step entirely from the process by using a synthesis method that inherently produces high-purity NACA. This eliminates the need for complex chromatographic purification equipment and operations, simplifying the overall manufacturing process while maintaining regulatory compliance.
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
This process yields NACA with reduced diNACA levels and increased purity, providing a scalable and efficient method for producing NACA without the need for chromatographic purification, and utilizes impurities B1 and B2 as unique identifiers for anticounterfeit measures.
Implementation Method 1
contacting cystine with methanol and a chlorinating reagent to form an organic solution containing cystine dimethylester dihydrochloride
Implementation Method 2
contacting cystine with methanol and a chlorinating reagent to form an organic solution containing cystine dimethylester dihydrochloride
Implementation Method 3
combining the dried or undried cystine dimethylester dihydrochloride with triethylamine, acetic anhydride, and acetonitrile to form di-N-acetylcystine dimethylester
Implementation Method 4
mixing the di-N-acetylcystine dimethylester with ammonium hydroxide to form di-N-acetylcystine amide
Implementation Method 5
reducing the di-N-acetylcystine amide to NACA with a reducing agent, an organic solvent, and a base
Data Source
AI summary
Provided herein are compositions and methods of providing an effective amount of an N-acetylcysteine amide (NACA) or diNACA sufficient to increase the concentration of NACA or diNACA in the affected tissue to biochemically reduce oxidative stress-related damage to tissue; utilizing NACA or diNACA that comprises at least one of impurities B1 or B2, which are indicative of NACA or diNACA manufactured by a process comprising: contacting cystine with methanol and a chlorinating reagent to form an organic solution containing cystine dimethylester dihydrochloride and optionally isolating and drying the cystine dimethylester dihydrochloride; combining the dried or undried cystine dimethylester dihydrochloride with triethylamine, acetic anhydride, and acetonitrile to form di-N-acetylcystine dimethylester; mixing the di-N-acetylcystine dimethylester with ammonium hydroxide to form di-N-acetylcystine amide (diNACA or NPI-002); and reducing the di-N-acetylcystine amide to N-acetylcysteine, NACA or NPI-001 with a reducing agent, an organic solvent, and a base.