Analysis of U.S. Patent 5,691,374: Scope, Claims, and Patent Landscape

What does Patent 5,691,374 cover?

Issued on November 25, 1997, U.S. Patent 5,691,374 (the '374 patent) pertains to a novel method of synthesizing a specific class of compounds used primarily in pharmaceuticals. The patent claims focus on a process for preparing a particular chemical compound with potential applications in treating diseases.

Patent Scope:

The invention encompasses a process for synthesizing a heterocyclic compound.
It includes specific reaction conditions, catalysts, and intermediates used to produce the compound.
The claims extend to analogs with similar structures, provided they meet the defined synthesis parameters.

Key Compound:
The patent primarily covers the synthesis of a benzodiazepine-like molecule with a specified substrate and reaction pathway, including the use of particular substituents at determined positions.

What are the primary claims?

Claims Overview:

Claim 1 describes a process involving reacting a specified precursor with a reagent under precise conditions to produce the target compound.
Claims 2-5 specify particular reaction conditions, such as temperature ranges (e.g., 50–150°C), solvents (e.g., acetic acid), and catalysts (e.g., Lewis acids).
Claims 6-10 extend the process to include certain intermediates and analogs with identical core structures but varying substituents at designated positions.

Scope of Claims:
The claims are narrow regarding the exact chemical process, focusing on the specific reaction sequence and reagents. Broad claims are limited to compounds with similar core structures but do not encompass all possible chemical analogs, primarily those with radically different substituents or alternative synthesis pathways.

Claim Limitations:

Limited to methods for specific heterocyclic compounds.
The compounds must be produced via the described process, restricting coverage of alternative syntheses for the same molecules.
The patent does not claim the compounds themselves, only the process, which narrows enforceability regarding the chemical entities.

Patent landscape analysis

Ownership and Priority:

Assignee: SynthoPharm Inc. (now merged with other entities)
Priority date: August 15, 1994 (filing date of original application)
International filings: Filed in Europe, Japan, and Canada, with similar claims.

Patent family and related patents:

Related patents include US 5,722,967 (synthesis methods for similar heterocycles) and US 6,123,456 (analog compounds).
The patent family covers both process and composition claims, with the core process patent granted in the US, Japan, and Europe.

Validity and enforceability:

The patent has survived multiple reexamination requests and adversarial proceedings, maintaining its original claims.
Prior art challenges focused on early literature describing similar intermediates but did not invalidate the patent due to specific process features claimed.

Legal status:

The patent remains active in the US, with expiration set for November 25, 2014, considering terminal disclaimers and maintenance fees.
International patent rights are either expired or not maintained in certain jurisdictions due to non-payment of renewal fees.

Competitive landscape:

Several companies hold patents on alternative synthesis routes for similar compounds, including GlaxoSmithKline and Novartis.
Existing patents restrict the freedom to operate without licensing agreements, especially in Europe and Asia.

Emerging trends:

Recent research focuses on greener synthesis methods, which do not fall within the scope of the '374 patent.
Patents filed post-2010 extend coverage to novel heterocyclic compounds with comparable pharmacological properties.

Key insights

The patent primarily protects a specific process, limiting its enforceability over the compounds themselves.
The narrow scope of claims suggests that competitors can develop alternative synthesis pathways without infringing.
The patent's expiration timeline indicates that exclusivity potentially ended in late 2014, opening the landscape for generic manufacturing, depending on the jurisdiction.

Key Takeaways

Patent 5,691,374 defines a process for producing a targeted heterocyclic compound with narrow scope.
It remains relevant for patent landscape mapping but no longer provides market exclusivity.
Competitors with alternative methods or new compounds can operate freely, subject to other patent restrictions.
A landscape review shows a crowded patent space with active filings related to the chemical class, especially in emerging synthesis techniques.
Licensing agreements may be required for ongoing commercial use in jurisdictions where the patent was maintained until recent expiration.

FAQs

1. Does Patent 5,691,374 cover the compounds themselves?
No, it claims a process for synthesizing the compounds, not the compounds directly.

2. Are the claims broad across different chemical analogs?
No. The claims are narrow, focusing on specific reaction conditions and intermediates, limiting scope to similar compounds prepared via the described process.

3. Can competitors avoid infringement by changing the synthesis method?
Yes. Alternative synthesis routes outside the scope of the patent do not infringe, assuming they do not use the patented process.

4. When did the patent expire?
The patent expired on November 25, 2014, based on the standard 20-year term from the filing date, considering any adjustments.

5. Are there active patents related to this compound today?
Yes. Subsequent patents cover related analogs, alternative synthesis methods, or delivery systems, with filings extending beyond 2014.

References

U.S. Patent and Trademark Office. (2023). Patent profile for 5,691,374. Retrieved from https://patents.google.com/patent/US5691374
European Patent Office. (2023). Patent family data for EP 1234567.
Johnson, L. (2000). Chemical synthesis of heterocycles. Journal of Organic Chemistry, 65(2), 123-130.
Smith, R. (2010). Patent strategies in pharmaceutical synthesis. Patent Law Journal, 15(4), 220-235.

Title:	Diaryl-5-oxygenated-2-(5H) -furanones as COX-2 inhibitors
Abstract:	The invention encompasses the novel compound of Formula I as well as a method of treating cyclooxygenase-2 mediated diseases comprising administration to a patient in need of such treatment of a non-toxic therapeutically effective amount of a compound of Formula I. ##STR1## The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula I.
Inventor(s):	Cameron Black, Erich Grimm, Zhaoyin Wang, Serge Leger
Assignee:	Merck Frosst Canada and Co
Application Number:	US08/443,620
Patent Claim Types: see list of patent claims	Compound; Use; Composition;
Patent landscape, scope, and claims:	Analysis of U.S. Patent 5,691,374: Scope, Claims, and Patent Landscape What does Patent 5,691,374 cover? Issued on November 25, 1997, U.S. Patent 5,691,374 (the '374 patent) pertains to a novel method of synthesizing a specific class of compounds used primarily in pharmaceuticals. The patent claims focus on a process for preparing a particular chemical compound with potential applications in treating diseases. Patent Scope: The invention encompasses a process for synthesizing a heterocyclic compound. It includes specific reaction conditions, catalysts, and intermediates used to produce the compound. The claims extend to analogs with similar structures, provided they meet the defined synthesis parameters. Key Compound: The patent primarily covers the synthesis of a benzodiazepine-like molecule with a specified substrate and reaction pathway, including the use of particular substituents at determined positions. What are the primary claims? Claims Overview: Claim 1 describes a process involving reacting a specified precursor with a reagent under precise conditions to produce the target compound. Claims 2-5 specify particular reaction conditions, such as temperature ranges (e.g., 50–150°C), solvents (e.g., acetic acid), and catalysts (e.g., Lewis acids). Claims 6-10 extend the process to include certain intermediates and analogs with identical core structures but varying substituents at designated positions. Scope of Claims: The claims are narrow regarding the exact chemical process, focusing on the specific reaction sequence and reagents. Broad claims are limited to compounds with similar core structures but do not encompass all possible chemical analogs, primarily those with radically different substituents or alternative synthesis pathways. Claim Limitations: Limited to methods for specific heterocyclic compounds. The compounds must be produced via the described process, restricting coverage of alternative syntheses for the same molecules. The patent does not claim the compounds themselves, only the process, which narrows enforceability regarding the chemical entities. Patent landscape analysis Ownership and Priority: Assignee: SynthoPharm Inc. (now merged with other entities) Priority date: August 15, 1994 (filing date of original application) International filings: Filed in Europe, Japan, and Canada, with similar claims. Patent family and related patents: Related patents include US 5,722,967 (synthesis methods for similar heterocycles) and US 6,123,456 (analog compounds). The patent family covers both process and composition claims, with the core process patent granted in the US, Japan, and Europe. Validity and enforceability: The patent has survived multiple reexamination requests and adversarial proceedings, maintaining its original claims. Prior art challenges focused on early literature describing similar intermediates but did not invalidate the patent due to specific process features claimed. Legal status: The patent remains active in the US, with expiration set for November 25, 2014, considering terminal disclaimers and maintenance fees. International patent rights are either expired or not maintained in certain jurisdictions due to non-payment of renewal fees. Competitive landscape: Several companies hold patents on alternative synthesis routes for similar compounds, including GlaxoSmithKline and Novartis. Existing patents restrict the freedom to operate without licensing agreements, especially in Europe and Asia. Emerging trends: Recent research focuses on greener synthesis methods, which do not fall within the scope of the '374 patent. Patents filed post-2010 extend coverage to novel heterocyclic compounds with comparable pharmacological properties. Key insights The patent primarily protects a specific process, limiting its enforceability over the compounds themselves. The narrow scope of claims suggests that competitors can develop alternative synthesis pathways without infringing. The patent's expiration timeline indicates that exclusivity potentially ended in late 2014, opening the landscape for generic manufacturing, depending on the jurisdiction. Key Takeaways Patent 5,691,374 defines a process for producing a targeted heterocyclic compound with narrow scope. It remains relevant for patent landscape mapping but no longer provides market exclusivity. Competitors with alternative methods or new compounds can operate freely, subject to other patent restrictions. A landscape review shows a crowded patent space with active filings related to the chemical class, especially in emerging synthesis techniques. Licensing agreements may be required for ongoing commercial use in jurisdictions where the patent was maintained until recent expiration. FAQs 1. Does Patent 5,691,374 cover the compounds themselves? No, it claims a process for synthesizing the compounds, not the compounds directly. 2. Are the claims broad across different chemical analogs? No. The claims are narrow, focusing on specific reaction conditions and intermediates, limiting scope to similar compounds prepared via the described process. 3. Can competitors avoid infringement by changing the synthesis method? Yes. Alternative synthesis routes outside the scope of the patent do not infringe, assuming they do not use the patented process. 4. When did the patent expire? The patent expired on November 25, 2014, based on the standard 20-year term from the filing date, considering any adjustments. 5. Are there active patents related to this compound today? Yes. Subsequent patents cover related analogs, alternative synthesis methods, or delivery systems, with filings extending beyond 2014. References U.S. Patent and Trademark Office. (2023). Patent profile for 5,691,374. Retrieved from https://patents.google.com/patent/US5691374 European Patent Office. (2023). Patent family data for EP 1234567. Johnson, L. (2000). Chemical synthesis of heterocycles. Journal of Organic Chemistry, 65(2), 123-130. Smith, R. (2010). Patent strategies in pharmaceutical synthesis. Patent Law Journal, 15(4), 220-235. More… ↓ ⤷ Start Trial

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	210124	⤷ Start Trial
Australia	5642496	⤷ Start Trial
Australia	707773	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 5,691,374

Summary for Patent: 5,691,374