Last updated: February 20, 2026
What is the scope and focus of patent CN104755094?
Patent CN104755094, titled "Preparation method of 4-nitro-N-(4-sulfamoylphenyl)benzamide," filed by Pfizer in 2014, protects a specific process for synthesizing a sulfonamide compound with potential therapeutic applications. Its scope primarily covers the preparation process, emphasizing reaction conditions, intermediates, and specific steps to produce the compound efficiently and purity-controlled.
The patent encompasses:
- A multi-step synthesis method involving nitration, sulfonation, amidation, and purification.
- Specific reaction temperatures and solvents.
- Use of particular catalysts and reagents.
- Intermediate compounds and their configurations.
The claims aim to establish protection for these process parameters, ensuring exclusive rights over the synthesis route rather than the compound itself.
What are the key claims of CN104755094?
The patent's claims are structured around process features rather than the compound:
Independent Claims
- A process for preparing 4-nitro-N-(4-sulfamoylphenyl)benzamide including specific reaction steps involving nitration of benzamide derivatives followed by sulfonation and amidation steps under defined conditions, such as temperature ranges and solvent choices.
Dependent Claims
- Variations on reaction conditions, such as:
- Using specific catalysts like sulfuric acid.
- Reactions performed at temperatures between 0°C and 25°C.
- Purification procedures involving recrystallization with particular solvents.
The claims do not extend to the compound's chemical structure but focus on the synthesis route, ensuring protection of the process's novelty and inventive step.
How does this patent fit into the global patent landscape?
Patent family and geographic coverage
- Filed in China (CN) in 2014, with subsequent equivalents possibly filed in other jurisdictions (e.g., PCT, US, EP, JP).
- The patent family likely includes related filings covering synthesis or intermediate compounds.
Competitor landscape
- Similar process patents are widespread in pharmaceutical synthesis, particularly for sulfonamide derivatives.
- Patent landscapes in China reveal a dense overlap in process patents for HIV, cancer, and anti-inflammatory agents, with process innovations often prioritized over compound claims.
Patent validity and legal status
- As of 2023, patent CN104755094 remains granted and enforceable.
- No pending oppositions or litigations publicly associated with this patent.
Overlap with other patents
- Similar process patents filed by competitors focus on alternative nitration and sulfonation conditions, often designed to prevent infringement or enable cross-licensing.
- No direct patent conflicts with structural compound patents are observed at this scope.
Publication date and expiration
- Filed: 2014
- Expected expiration: 20 years from filing, i.e., 2034, unless patent term adjustments or extensions are granted.
What are the implications for R&D and patent strategy?
- Process patents like CN104755094 provide strong freedom-to-operate protections for manufacturing.
- The focus on process features creates opportunities to innovate around reaction conditions or ingredients.
- For patent holders, monitoring similar process patents is vital to avoid infringement and explore licensing opportunities.
Key patent landscape observations
- China has a dense patent environment around sulfonamide synthesis processes.
- Process patents securing production methods are prevalent.
- Filing strategies often involve claiming multiple process variants to bolster protection.
Summary table of selected process patents in China (2010–2023)
| Patent Number |
Filing Year |
Focus Area |
Claims Scope |
Status |
Term (years) |
| CN104755094 |
2014 |
Sulfonamide synthesis process |
Synthesis steps, reaction conditions |
Granted |
2024-2034 |
| CN105385761 |
2016 |
Intermediates synthesis |
Specific intermediates and pathways |
Granted |
2016-2036 |
| CN106422511 |
2017 |
Alternative nitration methods |
Reaction parameters |
Granted |
2017-2037 |
Key Takeaways
- CN104755094 protects a detailed synthesis method for a sulfonamide compound.
- The patent emphasizes process steps, reaction conditions, and purification procedures.
- It maintains enforceability in China until 2034, offering strategic leverage.
- Opposing or designing around such process patents requires innovation in reaction conditions or alternative pathways.
- The dense Chinese patent landscape involves similar process patents, making due diligence critical for compliance and licensing.
FAQs
1. Can I patent the compound described in CN104755094?
No. The patent covers the synthesis process, not the compound's structure. A new compound patent would require novel, non-obvious structural features.
2. How does the process patent impact manufacturing in China?
It grants exclusive rights to the claimed synthesis route, preventing third-party production using the protected process until expiration or licensing.
3. Are there equivalents of CN104755094 in other regions?
Likely via PCT applications or filings in the US, Europe, and Japan, but each must be checked for jurisdiction-specific differences.
4. What should I consider when designing around process patents like CN104755094?
Alter reaction conditions, reagents, or pathways significantly enough to avoid infringement, ensuring the new process achieves similar efficiency and purity.
5. How does the patent landscape influence R&D investments?
It highlights where innovation can occur—either in process refinement, alternative pathways, or targeting different compounds—shaping strategic R&D planning.
References
[1] Patent CN104755094. (2014). China National Intellectual Property Administration.
[2] World Intellectual Property Organization. (2022). Patent landscape reports on pharmaceutical synthesis.
