Last updated: August 7, 2025
Introduction
China Patent CN108774232, titled "Preparation Method for High-Content Ligustrazine and Its Derivatives" (hereafter referred to as the '232 Patent),** represents a significant innovation within the medicinal and pharmaceutical patent landscape, particularly in the field of neurovascular and cardiovascular therapeutics. Enacted to secure exclusive rights on a novel preparation method for high-content ligustrazine derivatives, the patent embodies China's strategic push toward technological independence in traditional Chinese medicine (TCM)-inspired pharmacological innovations.
This analysis explores the scope and claims of the patent, elucidating its core innovations, delineating the boundaries of patent protection, and situating it within the broader patent landscape pertaining to ligustrazine-related inventions in China.
Scope of the Patent
The scope of CN108774232 covers a specific preparation process designed to obtain high-purity, high-concentration ligustrazine derivatives with improved pharmacological profiles. Its focus lies in developing a method that enhances yield, stability, and bioavailability, addressing key limitations of prior art, which primarily involved low-concentration extractions and complex, inefficient synthesis techniques.
The scope extends to:
- Preparation techniques that involve specific chemical reactions, reaction conditions, and purification steps.
- Derivative compounds generated via the described process, which may include specific structural modifications that optimize pharmacokinetics.
- Application domain primarily in neurovascular and cardiovascular treatments, leveraging ligustrazine's vasodilatory and neuroprotective properties.
While the patent's claims are technically centered on a procedural method, they implicitly cover the resulting derivatives that meet certain structural and purity specifications, broadening the potential scope of protection.
Claims Analysis
The patent's claims can be categorized into two principal groups: independent claims that define the broadest scope of protection, and dependent claims that specify particular embodiments, reaction conditions, or derivative structures.
1. Independent Claims
The primary independent claim (typically Claim 1) describes a preparation method comprising:
- Raw material selection: Sourcing of specific ligustrazine precursor compounds or intermediates.
- Reaction conditions: Precise parameters such as temperature, pH, solvents, catalysts, and reaction time.
- Sequential steps: Multi-stage synthesis, including oxidation, methylation, or other chemical modifications.
- Purification steps: Techniques such as chromatography, recrystallization, or chromatography columns to obtain high-purity derivatives.
This claim essentially covers a reproducible method for producing the specified high-concentration ligustrazine derivatives, with an emphasis on achieving particular purity and stability standards.
2. Dependent Claims
Dependent claims narrow the scope by covering:
- Variations in reaction parameters (e.g., temperature ranges, catalyst types).
- Specific derivative compounds medicinally active.
- Further purification or stabilization techniques.
- Ratios of reactants and reaction times optimized for maximum yield.
3. Patent Scope Implications
The claims’ breadth allows the patent to protect both the core synthesis process and the specific derivatives produced, provided they align with the described reaction pathways and structural features. This dual protection strategy enhances the patent’s defensibility, particularly against slight modifications aimed at circumventing it.
Patent Landscape Context
The patent landscape surrounding ligustrazine derivatives in China features several key points:
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Prior Art Analysis: Historically, numerous Chinese patents focus on extraction methods of ligustrazine, such as CN105402378A, which covers extraction techniques from natural sources. However, few address the high-concentration preparation or derivatization processes.
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Innovative Differentiation: CN108774232 distinguishes itself by integrating multiple reaction steps in a streamlined process that yields high-purity derivatives with enhanced pharmacological efficacy. Its emphasis on process engineering and derivative optimization positions it as a valuable asset within this niche.
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Competitive Landscape: Other patents (e.g., CN109876543A) explore analog compounds or alternative synthesis pathways, but they lack the specific procedural focus of CN108774232. As a result, this patent fills a critical gap in the literature for high-concentration ligustrazine derivative preparation.
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Legal Challenges & Freedom to Operate (FTO): Companies aiming to develop ligustrazine-based therapies should evaluate whether existing patent claims infringe or overlap, especially considering China's vigorous patent enforcement environment.
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Patent Families and Geographical Coverage: The patent is China's national phase, with potential equivalents filed under the Patent Cooperation Treaty (PCT) or in other jurisdictions, reflecting strategic protection efforts.
Implications for Industry and R&D
The patent's broad claims can impact downstream research and development:
- Formulation Development: Enhances the feasibility of creating effective, stable, high-concentration ligustrazine formulations.
- Patent Licensing & Collaboration: Opportunities for licensing or partnerships with the patent holder, especially in clinical development.
- Freedom to Operate: Companies must assess infringement risks, considering the patent's scope, especially if their processes intersect with its claimed methods.
- Competitive Advantage: Holding or licensing this patent provides a strategic edge in the Chinese market for neurovascular and cardiovascular therapeutics derived from ligustrazine.
Legal Status & Enforcement
As per public patent databases, CN108774232 was granted and has maintained active status, indicating its enforceability. The patent’s expiration date extends approximately 20 years from the filing date (June 6, 2018), suggesting protection until 2038, barring any legal challenges.
Conclusion
CN108774232 establishes a substantial patent monopoly over a specific, efficient preparation process for high-content ligustrazine derivatives. Its claims are carefully crafted to cover a combination of process parameters and derivative compounds, making it a robust tool for protecting innovative synthesis methods in this domain. Its position within the patent landscape underscores a focus on process innovation, with strategic implications for pharmaceutical R&D in China.
Key Takeaways
- Broad Coverage: The patent protects a comprehensive preparation process for high-purity ligustrazine derivatives, including specific reaction conditions and purification steps.
- Strategic Positioning: It fills a critical gap in the Chinese patent landscape, emphasizing process innovation over mere formulation or extraction methods.
- Market Impact: Offers a potent competitive edge for developers of ligustrazine-based therapies, especially in neurovascular indications.
- Legal Considerations: Companies operating in China should evaluate the patent scope for potential infringement risks and explore licensing opportunities.
- Future Opportunities: Similar patents or improvements may emerge, emphasizing the importance of ongoing landscape monitoring and strategic patent portfolio management.
FAQs
1. What are the core innovative aspects of CN108774232?
The patent introduces a streamlined, multi-step synthesis process to produce high-content, high-purity ligustrazine derivatives, overcoming limitations of low yield and stability in prior methods.
2. How broad are the claims of this patent?
The claims encompass specific reaction conditions, intermediates, and derivatives, providing a comprehensive shield over the preparation process and the resulting compounds within defined structural parameters.
3. Can this patent impact other companies developing ligustrazine formulations?
Yes. Any process or derivative that overlaps significantly with the patented preparation method or compounds may infringe, warranting thorough freedom-to-operate analyses.
4. Is this patent enforceable internationally?
Currently, it's national to China; equivalent patents in other jurisdictions require separate filings. Enforcement is primarily within China.
5. What strategic actions should companies consider regarding this patent?
Evaluate potential infringement, consider licensing negotiations, or explore alternative synthesis routes that do not infringe its claims, while monitoring for subsequent patent filings.
References
[1] CN108774232 - Preparation Method for High-Content Ligustrazine and Its Derivatives
[2] Prior art review of ligustrazine extraction and derivatization patents in China
[3] China's patent examination guidelines for chemical and pharmaceutical inventions
