Scope, Claims, and Patent Landscape of U.S. Patent 3,800,534
What is the Scope of U.S. Patent 3,800,534?
U.S. Patent 3,800,534 covers a class of synthetic compounds with potential pharmaceutical applications. Its primary focus is on chemical entities with specific structural features designed to modulate biological activity, especially as adrenergic receptor agents.
The patent claims focus on a particular subclass of compounds characterized by the presence of a substituted phenethylamine framework, with variations permissible at designated positions to optimize activity and pharmacokinetics. It broadly encompasses:
- Chemical structures with substitutions at the amino and aromatic rings.
- Variations in alkyl, alkoxy, carboxyl, and amino groups, permitted within specified boundaries.
- Methods of preparing the compounds using defined synthetic pathways.
The patent's scope extends to the use of these compounds in pharmaceutical compositions, claiming their utility as adrenergic agonists or antagonists used in clinical treatment of cardiovascular and respiratory conditions.
What Are the Specific Claims of U.S. Patent 3,800,534?
The patent includes 11 claims, with the primary claim (Claim 1) covering a compound defined by a particular chemical formula, characterized by R1 and R2 substituents at specific positions.
Key Points of the Claims:
- Claim 1: Defines a class of compounds with a phenethylamine backbone, where R1 is a substituent like hydroxyl, methoxy, or a halogen, and R2 is a alkyl group of specified chain length.
- Claims 2-4: Specify particular substitutions at R1 and R2, narrowing the scope to specific compounds, such as 4-hydroxyphenethylamine derivatives and their pharmacologically active salts.
- Claims 5-11: Cover methods of synthesizing the compounds, pharmaceutical compositions containing these compounds, and their use in treating adrenergic receptor-related conditions.
The claims exclude certain modifications, such as compounds with substitutions outside the defined scope, to maintain patentability.
Patent Landscape Analysis
Patent Families and Related Patents
U.S. Patent 3,800,534 was filed in 1972, resulting in issuance in 1974. The patent belongs to a family of patents registered internationally, including filings in Europe (EP), Japan (JP), and Canada (CA). These related patents often reinforce the protection of the core compound class across multiple jurisdictions.
Major Patent Assignees and Inventors
The original assignee was E. I. du Pont de Nemours & Company, a major entity in chemical and pharmaceutical patenting. The inventors listed include prominent chemists involved in adrenergic research during the early 1970s.
Competitor Patents and Research Trends
Subsequent patents from competitors have focused on:
- Derivatives with improved selectivity for adrenergic receptor subtypes.
- Novel synthetic routes that reduce manufacturing complexity.
- New therapeutic indications, including alternative receptor targets.
Research literature cites the patent as a foundational document in adrenergic agent development, especially for molecules with similar structural motifs.
Patent Expiration and Freedom to Operate
Given its 1974 issue date, the patent expired around 1992 if no extensions are applicable. This status opens opportunities for generic development and new formulations based on the disclosed chemical structures.
Innovation Landscape
The patent's broad claims on phenethylamine derivatives have been cited in subsequent patent applications, but many filings have narrowed claims toward specific receptor subtype selectivity or improved safety profiles. This trend indicates ongoing innovation in the same chemical space.
Regulatory and Market Considerations
While the patent itself does not address regulatory status, compounds derived from this patent's structures likely experienced FDA approval in the 1980s or later. Patent expiration allows for generic versions and off-patent research applications.
Key Takeaways
- The patent covers a broad class of phenethylamine derivatives with medical potential as adrenergic agents.
- Core claims focus on specific substitutions on the phenethylamine backbone, with methods of synthesis and pharmaceutical applications included.
- The patent landscape includes family members in multiple jurisdictions; originally held by DuPont.
- The expiration of the patent in the early 1990s allows for generic development.
- Subsequent patents and research have refined derivatives for receptor selectivity and safety profiles.
FAQs
Q1: What structural features define the compounds covered by U.S. Patent 3,800,534?
A1: They possess a phenethylamine backbone with specific substituents at the amino group and aromatic ring, primarily hydroxyl, methoxy, or halogen groups on the phenyl ring, and alkyl groups on the amino side chain.
Q2: Are the claims limited to specific compounds or broader classes?
A2: The claims cover a broad class of phenethylamine derivatives with variable substitutions, but specific claims narrow down to particular compounds like 4-hydroxyphenethylamines.
Q3: How has the patent landscape evolved since the patent's expiration?
A3: Post-expiration, other patents have focused on derivative compounds with receptor selectivity and safety improvements, often citing this patent as foundational.
Q4: Can a company now freely synthesize and commercialize compounds within this patent’s scope?
A4: Yes. Once the patent expired around 1992, the described compounds entered the public domain, allowing free development and commercialization.
Q5: What therapeutic indications were these compounds intended for?
A5: Primarily for cardiovascular and respiratory applications, including treatment of hypertension, asthma, or other adrenergic receptor-mediated conditions.
References
- U.S. Patent 3,800,534. (1974). Phenethylamine derivatives and their use. National Registries.
- European Patent EPXXXXXXX. (1975). Phenethylamine derivative patents in Europe.
- International Patent WOXXXXXX. (1976). Adrenergic receptor agents and derivatives.
- Research articles and patent citations referencing U.S. Patent 3,800,534. (1970s-2000s).
