United States Patent 4,335,121: A Detailed Analysis of Scope, Claims, and Patent Landscape
Introduction
United States Patent 4,335,121, titled "Androstane carbothioates," is a significant patent in the field of organic chemistry, particularly focusing on steroids and their derivatives. This patent, granted in 1982, outlines the discovery, synthesis, and therapeutic applications of certain androstane compounds. Here, we will delve into the scope, claims, and the broader patent landscape surrounding this invention.
Background and Context
The patent was filed by researchers who discovered that certain androstane carbothioates possess anti-inflammatory properties. This discovery was part of a broader effort to develop new therapeutic agents, particularly in the realm of non-steroidal anti-inflammatory drugs (NSAIDs)[4].
Scope of the Patent
Chemical Compounds
The patent describes the synthesis and properties of androstane carbothioates, which are derivatives of androstane 17β-carbothioic acids. These compounds are characterized by their specific chemical structures, including the presence of thiocarbamoyloxycarbonyl groups and other functional groups such as hydroxy, methyl, and methylene groups[1].
Therapeutic Applications
The primary focus of the patent is on the anti-inflammatory activity of these compounds. The inventors identified that these androstane carbothioates could be used as therapeutic agents for treating inflammatory conditions, potentially offering an alternative to existing NSAIDs[1].
Claims of the Patent
The patent includes several claims that define the scope of the invention:
Chemical Structure Claims
- Claims define the specific chemical structures of the androstane carbothioates, including the configuration of the cyclopenta(a)hydrophenanthrene skeleton and the presence of oxygen-containing hetero rings[1].
Synthesis Claims
- The patent details the methods for synthesizing these compounds, including the use of specific reagents and reaction conditions. For example, it mentions the use of 2-halo-N-alkyl or 2-halo-N-phenyl-pyridinium or pyrimidinium salts[1].
Therapeutic Claims
- Claims also cover the therapeutic uses of these compounds, particularly their anti-inflammatory and potential anti-allergic properties[1].
Patent Landscape
Related Patents and Prior Art
The patent landscape surrounding US 4,335,121 includes other patents related to steroid derivatives and anti-inflammatory compounds. For instance, patents like US 6,537,983 B1 describe similar anti-inflammatory androstan derivatives, highlighting the ongoing research in this area[4].
Classification and Categorization
The patent is classified under various categories, including C07J (Steroids) and A61P (Specific therapeutic activity of chemical compounds or medicinal preparations). This classification indicates its relevance to both organic chemistry and medical science[1].
Legal and Regulatory Aspects
Expiration and Legal Status
The patent has expired, as indicated by its legal status. This means that the protected period during which the inventors held exclusive rights to the invention has ended, and the technology is now in the public domain[1].
International Harmonization
The broader patent landscape is influenced by efforts to harmonize patent laws across different countries. This is reflected in changes such as the transition from a first-to-invent to a first-inventor-to-file system, as seen in the Leahy-Smith America Invents Act[3].
Impact and Significance
Therapeutic Impact
The discovery of anti-inflammatory androstane carbothioates contributed to the development of new therapeutic agents. These compounds offered potential alternatives or complements to existing treatments for inflammatory conditions[1].
Scientific Contribution
The patent represents a significant scientific contribution to the field of steroid chemistry and pharmacology. It has influenced subsequent research and the development of related compounds with therapeutic potential[4].
Industry and Market Implications
Pharmaceutical Industry
The pharmaceutical industry has been a key beneficiary of such research. Companies like SmithKline Beecham Corporation (now part of GlaxoSmithKline) have been involved in the development and commercialization of similar compounds, as seen in patents like US 6,537,983 B1[4].
Market Competition
The expiration of the patent has opened up the market for generic versions of these compounds, potentially increasing competition and reducing costs for consumers.
Key Takeaways
- Chemical Innovation: The patent highlights significant chemical innovation in the synthesis and characterization of androstane carbothioates.
- Therapeutic Potential: These compounds have shown promise as anti-inflammatory agents, contributing to the development of new therapeutic options.
- Patent Landscape: The patent is part of a broader landscape of research and development in steroid chemistry and pharmacology.
- Legal and Regulatory: The patent's expiration and the broader legal framework influence the availability and use of these compounds.
- Industry Impact: The research has had a lasting impact on the pharmaceutical industry, driving further innovation and competition.
FAQs
Q: What are androstane carbothioates?
Androstane carbothioates are a class of steroid derivatives characterized by their specific chemical structures, including the presence of thiocarbamoyloxycarbonyl groups and other functional groups.
Q: What is the therapeutic application of androstane carbothioates?
These compounds have been identified as having anti-inflammatory properties, making them potential therapeutic agents for treating inflammatory conditions.
Q: Who were the inventors of this patent?
The patent does not specify individual inventors but was filed by researchers who discovered the anti-inflammatory properties of androstane carbothioates.
Q: What is the current legal status of the patent?
The patent has expired, meaning the protected period has ended, and the technology is now in the public domain.
Q: How does this patent fit into the broader patent landscape?
The patent is part of ongoing research in steroid chemistry and pharmacology, contributing to the development of new therapeutic agents and influencing subsequent patents in the field.
Cited Sources:
- US4335121A - Androstane carbothioates - Google Patents
- United States Patent and Trademark Office - Petitioner's Notice of Appeal
- Mastering Patent Claim Construction - Digital Commons @ Touro Law
- US6537983B1 - Anti-inflammatory androstan derivatives - Google Patents
