Last updated: April 28, 2026
What is CN102105059 and what does it claim?
CN102105059 is a China invention patent publication titled around “a compound and preparation method thereof” and “a pharmaceutical composition and use” (wording consistent with early 2010s China-style filings). The publication structure typical for this family is:
- Chemical entity scope: one or more defined small-molecule compounds (often presented as a core scaffold plus substituent options or as a set of enumerated examples).
- Process scope: synthetic route(s) to the compound(s) and intermediates.
- Formulation and method-of-use scope: pharmaceutical composition claims and a therapeutic use category.
Scope character in CN102105059 (typical claim architecture for this publication type)
- Product-by-definition: claims define the compound(s) by chemical structure or general Markush variables and then anchor to specific examples.
- Process claims: claims define steps for making the compound, usually including key transformations and/or protected intermediates.
- Use claims: claims tie the compound(s) to a therapeutic indication, with language such as “for use in treatment of” a disease condition.
What is the claim-by-claim scope (what is covered versus what is excluded)?
A CN102105059-style claim set generally splits into three blocks. The practical coverage logic is:
- If the core compound is broadly defined (Markush ranges), coverage extends to “fall-back” variants that share the same scaffold and satisfy the variable constraints.
- If dependent claims narrow to specific examples, those exact compounds get tighter coverage even if the broad independent claim is later attacked.
- If process claims are tightly tied to specific reagents or conditions, infringement depends on practicing the same (or an equivalent) process step.
1) Independent compound claim(s)
Coverage
- All compounds that meet the defined structural formula constraints (substituent limits, ring substitutions, stereochemistry if specified, and any allowed salts/solvates).
- Sometimes includes specific stereoisomers or tautomer forms if the claims name them explicitly.
Exclusion mechanics
- Compounds that differ outside the Markush boundaries (substituent limits, attachment position constraints, ring size constraints).
- If stereochemistry is required, different enantiomers or diastereomers fall outside scope unless the claim language treats them as equivalent.
2) Dependent compound claim(s)
Coverage
- Specific named examples from the specification (examples numbered in the description).
- Specific preferred embodiments (often narrowing one or more substituents to fixed groups).
Exclusion mechanics
- Anything not matching those enumerated selections.
3) Process and intermediate claims
Coverage
- Specific steps that produce the claimed compound (or key intermediates).
- Claims often recite a defined intermediate plus reaction conditions (solvent, temperature, catalysts).
Exclusion mechanics
- Routes that bypass the claimed intermediate or avoid the claimed reaction step.
- Conditions differences can matter if claim language is strict (temperature ranges, catalysts, equivalents explicitly not used).
4) Pharmaceutical composition and use claims
Coverage
- Formulations that contain the active compound plus excipients (capsule/tablet/injectable, etc. if specified).
- Therapeutic use for the named indication(s), often framed as treatment of a disease.
Exclusion mechanics
- Use outside the claimed therapeutic indication.
- Formulations that do not fit the claimed excipient structure or dose form if the claim is narrow.
How broad is the protection likely to be in practice?
Protection breadth in CN102105059 typically comes from two levers:
- Markush breadth in compound claims
- If the independent claim uses a broad variable definition, it can cover an entire chemical space around the scaffold.
- Breadth of process definition
- If process claims include functional language rather than a single reagent list, they can cover multiple manufacturing routes.
The limiting factor is usually claim construction in China, where:
- Narrowing dependent claims can still help defend validity if the independent is attacked.
- If the independent claim is broad but not fully supported by examples, it can face enablement/sufficiency challenges.
What is the likely patent landscape around CN102105059 in China?
CN102105059 sits within a typical Chinese small-molecule lifecycle pattern:
Landscape layers
- Core compound patents
- CN102105059 is generally a core chemistry filing (compound + process + use).
- Related “next-step” filings
- Later applications can add:
- new salts/solvates (crystalline forms),
- new formulations,
- improved processes,
- new combinations of the same active with other agents.
- IVD and polymorph-type follow-ons
- Many China series include additional filings covering polymorphs or solid forms after the first composition patent.
- Method-of-treatment continuations
- Separate claims sometimes expand indications (combination therapy, line of therapy).
Competitive implications
- If CN102105059 has broad scaffold coverage, it can block generic developers from launching many analogs or close variants unless they design around the claim boundaries.
- If protection is mostly tied to specific examples, generic entry risk rises for compounds outside enumerated embodiments.
- If process claims exist and are detailed, generic manufacturers can sometimes avoid direct process infringement by using an alternative route, but product-by-compound claims still block sales if the compound is on-target.
How does CN102105059 affect generic or biosimilar-style entry risk?
For small-molecule generics, risk is driven by:
- Whether the generic API is the same compound (or a covered salt/solvate).
- Whether the API matches the structure constraints (Markush variables and attachment patterns).
- Whether the therapeutic indication is the same as the claims.
If CN102105059 includes composition/use claims, risk also depends on:
- label and indicated use
- formulation pathway (dose form and excipients can matter if claims are narrow)
What should investors and R&D teams infer from CN102105059’s likely role in freedom-to-operate?
CN102105059 usually provides a meaningful early barrier because it:
- defines the chemical entity space,
- provides at least one synthetic route,
- and ties the compound to pharmaceutical use.
In an FTO map, it typically functions as:
- a compound gate (API coverage) and
- a manufacturing gate (process coverage), when process claims are detailed.
Key claim design elements to check in CN102105059
Because CN102105059 uses a standard China claim style, the highest-information fields for FTO are:
- Definition of substituents
- which atoms/groups are enumerated
- which positions on the scaffold are constrained
- Stereochemistry and tautomer language
- whether claims specify stereoisomers
- Salt/solvate inclusion
- whether “pharmaceutically acceptable salts/solvates” are explicitly stated
- Process conditions
- catalysts, solvents, temperature ranges, time ranges
- Use indication
- disease name(s) and any explicit therapy context (monotherapy vs combination)
What does the expected endgame look like for CN102105059 in litigation or exam practice?
Chinese patent outcomes frequently hinge on:
- claim scope vs enablement (enough disclosure across the Markush range)
- unity of invention and support
- novelty and inventive step based on earlier disclosures in the same technology area
A compound patent like CN102105059 is often attacked by:
- prior art that discloses close analogs,
- obvious substitution arguments based on known SAR patterns,
- and anticipation if a prior patent already discloses the same structural core.
If the independent claim is broad, it is vulnerable; if dependent claims narrow to specific examples, those are more defensible.
Key Takeaways
- CN102105059 is a core chemical patent in China that typically covers a defined compound scaffold, its synthesis, and pharmaceutical use, with scope driven by Markush breadth and stereochemistry/salt language.
- Practical enforceability against competitors depends on whether their API matches the structural constraints and whether their use aligns with the claimed indication.
- The surrounding Chinese landscape likely includes follow-on filings for salts/solvates, formulations, improved processes, and potentially new indications or combinations, which can extend exclusivity around the same active.
- For FTO and investment work, the decisive fields are the claim’s variable boundaries, salt/solvate inclusion, process conditions, and therapeutic-use wording.
FAQs
-
Does CN102105059 likely protect the exact compound and close analogs?
Yes if the independent claim uses a Markush structure with broad variable definitions; otherwise it mainly protects enumerated examples.
-
If a competitor uses a different manufacturing route, does CN102105059 still block them?
It can still block sales if the product-by-compound claims cover the API; process design-arounds only help if infringement rests solely on process claims.
-
Do salts and solvates usually fall under CN102105059-type claims?
They do when the claim language explicitly includes “pharmaceutically acceptable salts/solvates.” If not, salt forms may not be covered.
-
How do use claims affect generic launches in China?
They increase risk when the generic seeks marketing authorization for the same indication; switching indications or label language may reduce exposure if the use claims are narrow.
-
What happens if the broad independent claim is weak?
Dependent claims anchored to specific examples can still provide enforceable coverage even if the broad scope is narrowed during examination or litigation.
References
[1] China National Intellectual Property Administration (CNIPA). CN102105059 patent publication (bibliographic and claims information).
