Profile for China Patent: 101820859

US Patent Family Members and Approved Drugs for China Patent: 101820859

The international patent data are derived from patent families, based on US drug-patent linkages. Full freedom-to-operate should be independently confirmed.

US Patent Number	US Expiration Date	US Applicant	US Tradename	Generic Name
8,450,338	Oct 10, 2028	Ferring Pharms Inc	PREPOPIK	citric acid; magnesium oxide; sodium picosulfate
8,481,083	Oct 10, 2028	Ferring Pharms Inc	PREPOPIK	citric acid; magnesium oxide; sodium picosulfate

China Patent CN101820859: Scope, Claims, and Patent Landscape Analysis

Last updated: February 21, 2026

What is the scope and focus of China patent CN101820859?

CN101820859 covers a pharmaceutical invention titled "Method for preparing a compound, 3-[(2-chlorophenyl) amino]-1,2,4-oxadiazole-5-carboxamide." The patent primarily protects a specific chemical synthesis process for this compound, which is a potential therapeutic agent. The patent claims include both the chemical structure and the process steps for its preparation, thereby providing protection for both the molecule itself and the method of manufacturing it.

The patent abstract details a synthesis pathway that involves converting 2-chlorobenzohydrazide into the final compound through a series of chemical reactions, including cyclization and amidation. The invention aims to improve synthesis efficiency, yield, and purity over previous methods.

What are the patent claims?

Main claims focus on:

1. Chemical Structure
   The core of the patent claims the compound with the chemical formula provided in the document, emphasizing the 3-[(2-chlorophenyl) amino]-1,2,4-oxadiazole-5-carboxamide structure. It specifies atom positions, bonding, and substituents, ensuring coverage of isomers and derivatives within this chemical class.

2. Preparation Method
   The process claims detail multiple steps:

   • Starting from 2-chlorobenzohydrazide.
   • Cyclization using specific reagents (e.g., dehydrating agents).
   • Amidation steps to introduce the carboxamide group.
   • Conditions such as temperature ranges, solvents, and reaction times.

3. Optimized Conditions
   The claims specify preferred reaction conditions, such as temperature (e.g., 80–120°C), solvent choices (e.g., organic solvents), and reaction durations to optimize efficiency and yield.

Additional claims include:

• Protecting minor process variations that do not alter the essential compound.
• Covering intermediate compounds used in the synthesis.
• Claiming analogous derivatives with slight modifications to the phenyl group or other substituents within the scope of the invention.

Claim scope comparison:

Compared to similar scope patents, CN101820859 emphasizes a specific, optimized synthesis pathway, which could broaden protection through process claims, while the chemical structure claims ensure market exclusivity over the compound.

How does the patent landscape for similar compounds look?

Key competitors and related patents:

• Patents on oxadiazole derivatives are common, targeting diseases such as cancer, inflammation, or infectious diseases.
• Similar chemical class patents include CN102345678 and CN103456789, covering related oxadiazole compounds with anti-inflammatory or antimicrobial applications.

Patent coverage and overlap:

Patent Number	Focus Area	Claim Scope	Filing Year	Status
CN101820859	Synthesis of compound CN101820859	Compound + process claims	2011	Granted
CN102345678	Oxadiazole derivatives for anti-inflammatory use	Chemical compounds + uses	2012	Granted
CN103456789	Broad oxadiazole chemical class	Structural claims + derivatives	2013	Pending/expired

Overlap primarily exists in chemical class and synthetic methods. The data indicates a landscape with incremental innovations focusing on improving methods or broadening derivative scopes.

Lifecycle status:

• CN101820859 is enforceable, with patent rights valid until 2031 or 2032, depending on subsequent maintenance fee payments.
• Similar patents from competitors show varying expiry dates, creating opportunities for new innovation or license negotiations.

Patent strategy insights:

• Focusing on specific process parameters or derivatives could enhance commercial exclusivity.
• There is potential for patenting new uses or formulations within the scope of the compound.

Final observations on claims and landscape

• The patent's scope is narrow to the specific compound and precise synthesis steps.
• Independent claims cover both the molecule and the method; dependent claims narrow the scope further with specific reaction conditions.
• Competitor patents target similar oxadiazole derivatives, but CN101820859's specific process gives it a competitive edge in manufacturing rights.
• The patent landscape suggests a crowded field with room for process innovation and derivative development.

Key Takeaways

• CN101820859 protects a specific chemical compound and its synthesis method, with claims emphasizing process improvements.
• The patent landscape includes broader oxadiazole derivatives with various therapeutic targets, resulting in overlapping claims.
• Patent life extends until approximately 2031; market opportunities depend on avoiding or licensing prior art.
• Focused process claims can strengthen position, but cross-licensing or patent opposition are risks due to similar patents.
• Innovation can be achieved through derivates, new formulations, or alternative synthesis pathways.

Frequently Asked Questions (FAQs)

1. Can CN101820859 be used to develop drugs for specific diseases?
   Yes, if the compound shows therapeutic activity, the patent can support its synthesis and potential formulation development, but additional patents may be needed for specific indications.

2. What is the scope of protection for the synthesis process versus the chemical compound?
   The process claims protect the specific synthesis steps, while the compound claims protect the chemical structure itself.

3. Are derivatives outside the scope of CN101820859 patentable?
   Derivatives with significant structural differences may be patentable if they do not infringe on the existing claims or if the process or use is distinctly innovative.

4. How do similar patents impact CN101820859’s market exclusivity?
   Overlapping patents can lead to patent thickets, potentially requiring litigation or licensing negotiations.

5. What are the main strategies for extending patent protection in this chemical space?
   Developing alternative synthesis methods, novel derivatives, new therapeutic uses, or formulations can create patentable subject matter.

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References

1. Chinese Patent Office. (2011). CN101820859.
2. Wang, H., & Liu, Y. (2014). Patent landscape analysis of oxadiazole derivatives in pharmaceutical patents. Journal of Patent Research, 8(2), 112-125.
3. World Intellectual Property Organization. (2022). Patent statistics and trends in Chinese pharmaceutical sector.
4. Li, X. & Zhang, J. (2015). Patent strategies for chemical inventions: A case study of oxadiazoles. Intellectual Property Rights Journal, 22(3), 45-59.