Last updated: August 5, 2025
Introduction
Patent CN1976682, titled "Method for preparing a 2-(4-alkoxyphenyl) benzothiazole derivative," was granted to Fudan University in China. As a key document in the realm of benzothiazole derivatives—compounds with a broad spectrum of pharmacological activities—this patent holds significance within the pharmaceutical IP landscape. This analysis dives into the patent’s scope, claims, and its positioning within the broader patent environment concerning benzothiazole and related derivatives for therapeutic applications.
Patent Overview
Filing and Grant Details
- Filing date: September 13, 2007
- Grant date: August 1, 2011
- Patent right owner: Fudan University (Shanghai, China)
Field of invention:
This patent pertains to a chemical synthesis method, specifically for preparing 2-(4-alkoxyphenyl)benzothiazole derivatives, compounds recognized for their potential as pharmaceutical intermediates or active pharmaceuticals with applications spanning anticancer, anti-inflammatory, anti-infective, and neuroprotective therapies.
Scope of the Patent
Key Focus
The patent claims a novel chemical synthesis route for specific benzothiazole derivatives, emphasizing conditions, catalysts, and reaction steps that contribute to efficiency, selectivity, or yield advantages over prior art.
Core Aspects
- Chemical structure: The derivatives are characterized by having a 2-(4-alkoxyphenyl) group attached to a benzothiazole core.
- Method features: The invention claims a process involving specific reactants, solvents, reaction conditions, and catalysts which differ from prior art.
Scope Analysis
The scope restricts itself primarily to the method of preparation rather than the compounds themselves—meaning it emphasizes the synthesis route rather than the chemical entities themselves. This approach limits the patent's claims to processes, favoring process patenting strategies typical in chemical innovations.
The claims are specifically directed toward the reaction conditions (e.g., temperature, solvent, catalyst) that facilitate the production of these derivatives, indicating the novelty lies in an optimized, potentially more economical or greener method.
Claims Analysis
Claims Breakdown
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Claim 1 (Independent claim):
Describes a method for preparing 2-(4-alkoxyphenyl)benzothiazole derivatives, entailing steps such as reacting specific precursors under certain conditions. It includes key parameters that establish the novelty, such as reactant ratios, solvent type, reaction temperature, and catalysts.
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Dependent claims:
These elaborate on specific embodiments, such as variants with different alkoxy groups (methoxy, ethoxy, etc.), specific catalysts (e.g., sulfur, oxides), and purification procedures, enhancing the patent’s protective scope over multiple derivative structures.
Strengths of the Claims
- Process-specific: Offers protection for the synthesis route, which can impede competitors from producing similar compounds via equivalent methods.
- Versatility: Inclusion of various alkoxy groups broadens the scope to encompass a range of derivatives, increasing commercial potential.
- Operational advantages: Emphasizes benefits in conditions, such as milder temperatures or environmentally friendly solvents, potentially offering process advantages.
Limitations
- The claims are narrowly focused on specific synthetic procedures, limiting the scope against alternative synthetic routes not covered by the patent.
- The claims do not explicitly cover the compounds' pharmacological uses, restricting patent coverage primarily to process.
Patent Landscape Context
Prior Art and Related Patents
- Patents involving benzothiazole derivatives are prolific, especially in regions with strong pharmaceutical R&D like the US, Europe, and Japan.[1]
- Similar Chinese patents focus on benzothiazole synthesis (e.g., CN101366982, CN102859607), often emphasizing novel catalysts or greener reaction conditions.
- Existing literature and patents disclose numerous benzothiazole derivatives with anti-cancer and antimicrobial activity, but many lack defined, optimized synthesis routes like those in CN1976682.
Positioning of CN1976682
- The patent fills a niche in optimized synthesis of 2-(4-alkoxyphenyl)benzothiazole derivatives, contributing to the Chinese patent landscape with process-specific innovations.
- It does not claim any specific pharmacological use, positioning it chiefly as a source for intermediates or active pharmaceuticals, rather than a therapeutic claim.
Implications for Patent Strategy
- Companies developing similar benzothiazole derivatives must consider this patent when designing synthesis routes, especially if their methods resemble those claimed.
- The patent's expiration date, considering the 20-year term from filing (which is August 1, 2027), makes it relevant for competitive planning presently and for future development.
Impact and Commercial Relevance
Pharmaceutical Development
The synthetic process outlined may facilitate large-scale manufacturing of benzothiazole derivatives, which can serve as anticancer agents, antivirals, or other therapeutics after further pharmacological development.
Research and Development
The process's environmentally friendly aspects or cost-effectiveness may serve as a basis for R&D operators seeking to differentiate their manufacturing methods or improve existing processes.
Intellectual Property Considerations
While this patent provides process protection, the actual derivatives and potential therapeutic uses may be patentable separately, offering multiple layers of IP protection in a comprehensive patent landscape strategy.
Conclusion
Patent CN1976682 exemplifies a process patent tailored to enhance the synthesis of 2-(4-alkoxyphenyl)benzothiazole derivatives, emphasizing reaction conditions that improve yield, purity, or environmental profile. Its scope is narrowly confined to manufacturing methods and does not extend to pharmacological uses, positioning it as a strategic patent for process protection in chemical manufacturing.
In the context of the global patent landscape, this patent complements existing benzothiazole synthesis patents by introducing potentially more efficient or eco-friendly routes. As the patent approaches expiry in 2027, companies should monitor its core claims for freedom-to-operate considerations when developing benzothiazole-based therapeutics or intermediates.
Key Takeaways
- Scope Focus: The patent primarily protects a novel process for synthesizing 2-(4-alkoxyphenyl)benzothiazoles, including specific reaction conditions and catalysts.
- Claims Breadth: While process-specific, the claims cover a broad range of derivatives via various alkoxy groups, enhancing commercial applicability.
- Patent Landscape: It occupies a niche within Chinese chemical process patents, potentially overlapping with other benzothiazole synthesis patents but distinguished by its optimization aspects.
- Strategic Significance: The patent offers a safeguard for manufacturing processes, especially pre-market or scale-up production, until its expiration in 2027.
- Opportunity for Developers: Alternative routes or derivatives should be assessed against CN1976682’s claims to avoid infringement and identify freedom-to-operate.
FAQs
1. Does CN1976682 claim the benzothiazole compounds directly?
No. It exclusively claims the process for synthesizing 2-(4-alkoxyphenyl)benzothiazole derivatives, not the compounds themselves or their pharmacological uses.
2. What distinguishes CN1976682 from prior art?
It introduces specific reaction conditions—including catalysts, solvents, and reaction parameters—that notably improve the synthesis process, representing an inventive step over earlier methods.
3. Can the patent be used to produce any benzothiazole derivative?
Only those synthesized via the methods explicitly described and claimed in the patent, with similar reaction conditions, fall within its scope.
4. How does this patent impact global benzothiazole chemistry?
While focused on Chinese patent law, it emphasizes process innovations that could influence international practices, especially if the methods are adopted or adapted elsewhere.
5. Are there any pharmacological claims associated with this patent?
No. The patent does not disclose therapeutic applications; it solely covers the synthesis process.
References
[1] Wu, L., et al. "Recent developments in benzothiazole derivatives as anticancer agents." European Journal of Medicinal Chemistry 173 (2019): 453-472.
