New Pyrimidine Chemical Compounds for Treating Tumors
This patent describes specific new chemical compounds, called N-phenyl-2-pyrimidine-amine derivatives, designed with precise molecular structures for potential use in treating cancer.
Original patent title: “Pyrimidine derivatives and processes for the preparation thereof”
This patent describes specific new chemical compounds, called N-phenyl-2-pyrimidine-amine derivatives, designed with precise molecular structures for potential use in treating cancer. Granted to Ciba Geigy Corp in 1996 with 24 claims and 564 forward citations.
Key facts
Coverage
What does this patent actually cover?
This patent claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more → a specific group of N-phenyl-2-pyrimidine-amine chemical compounds, identified by a general chemical structure called Formula I. The claims precisely define various parts of this molecule, known as 'R' groups (R1 through R10), along with X, Y, and n. For example, R1 can be 4-pyrazinyl or 1-methyl-1H-pyrrolyl, and R2 and R3 are hydrogen or lower alkyl. Crucially, one or two of the R4-R8 positions must include a nitro group, a fluoro-substituted lower alkoxy group, or a specific radical of Formula II, which itself has detailed definitions for R9, X, Y, n, and R10. The patent abstractabstractA short summary at the front of the patent describing the invention. Not legally binding.Read more → states these compounds can be used in the therapy of tumoral diseases. An example compound would have R1 as 4-pyrazinyl, R2 and R3 as hydrogen, and one of R4-R8 as a radical of Formula II where R10 is an aliphatic radical with at least 5 carbon atoms.
The gap
What does this patent NOT cover?
- Does not cover pyrimidine derivatives that do not match the exact N-phenyl-2-pyrimidine-amine core structure of Formula I.
- Does not cover compounds where the R1 substituent is not one of the specifically listed groups, such as 4-pyrazinyl or 1-methyl-1H-pyrrolyl.
- Does not cover compounds where the R10 radical in Formula II has fewer than 5 carbon atoms if it is an aliphatic radical.
- Does not cover compounds where the R4-R8 substituents do not include at least one of the specified nitro, fluoro-substituted lower alkoxy, or Formula II radicals.
- Does not cover compounds where the R10 radical is an aromatic-aliphatic radical but the phenyl portion is substituted differently than described in claimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 3.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The noveltynoveltyThe requirement that an invention be different from anything publicly known before its priority date.Read more → lies in the specific combination of chemical groups attached to the N-phenyl-2-pyrimidine-amine core, particularly the detailed definitions for R1 and the specific requirements for at least one of the R4-R8 positions, which together yield compounds with therapeutic potential for tumors.
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Imatinib (Gleevec) - a pyrimidine derivative developed by Novartis for treating certain cancers.
Other tyrosine kinase inhibitors used in oncology.
Early-stage drug candidates targeting specific tumor pathways.
Why it matters
The bigger picture
This patent is foundational in pharmaceutical chemistry, defining a class of compounds with potential anti-tumor activity. It represents early work by Ciba Geigy, a company that later became part of Novartis, a major player in oncology. Such patents are critical for establishing intellectual property around new drug candidates, guiding further research and development in cancer treatment.
Filed
April 28, 1994
Granted
May 28, 1996
Market context
Who's building on this
Companies in this space
Novartis, as the successor to Ciba Geigy, continues to be a major force in oncology research and drug development, including small molecule inhibitors. Other pharmaceutical and biotech companies developing targeted cancer therapies, particularly kinase inhibitors, are working in related chemical spaces. Academic research institutions also build on such foundational chemical patents to explore new therapeutic agents.
Market impact
This patent contributed to the body of knowledge and intellectual property that allowed for the development of new classes of targeted cancer therapies. It helped define a chemical space for drug discovery, potentially enabling the creation of drugs like imatinib, which revolutionized the treatment of chronic myeloid leukemia and other cancers. Such patents can block competitors from developing similar compounds and encourage investment in specific research directions.
Claim 1 — Plain English
What this patent covers
This patent claims a specific group of N-phenyl-2-pyrimidine-amine chemical compounds, identified by a general chemical structure called Formula I. The claims precisely define various parts of this molecule, known as 'R' groups (R1 through R10), along with X, Y, and n. For example, R1 can be 4-pyrazinyl or 1-methyl-1H-pyrrolyl, and R2 and R3 are hydrogen or lower alkyl. Crucially, one or two of the R4-R8 positions must include a nitro group, a fluoro-substituted lower alkoxy group, or a specific radical of Formula II, which itself has detailed definitions for R9, X, Y, n, and R10. The patent abstract states these compounds can be used in the therapy of tumoral diseases. An example compound would have R1 as 4-pyrazinyl, R2 and R3 as hydrogen, and one of R4-R8 as a radical of Formula II where R10 is an aliphatic radical with at least 5 carbon atoms.
The clever bit
The novelty lies in the specific combination of chemical groups attached to the N-phenyl-2-pyrimidine-amine core, particularly the detailed definitions for R1 and the specific requirements for at least one of the R4-R8 positions, which together yield compounds with therapeutic potential for tumors.
What it does not cover
- Does not cover pyrimidine derivatives that do not match the exact N-phenyl-2-pyrimidine-amine core structure of Formula I.
- Does not cover compounds where the R1 substituent is not one of the specifically listed groups, such as 4-pyrazinyl or 1-methyl-1H-pyrrolyl.
- Does not cover compounds where the R10 radical in Formula II has fewer than 5 carbon atoms if it is an aliphatic radical.
- Does not cover compounds where the R4-R8 substituents do not include at least one of the specified nitro, fluoro-substituted lower alkoxy, or Formula II radicals.
- Does not cover compounds where the R10 radical is an aromatic-aliphatic radical but the phenyl portion is substituted differently than described in claim 3.
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
PatentBrief Score
Impact Score
Strong
Citation count
40/40
Highly cited
Claim breadth
16/20
Broad claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
20/20
Major company or institution
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$176K – $562K
Midpoint $351K · expired or expiring · industry ×3.0
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
24 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Zimmermann, J. (1996). New Pyrimidine Chemical Compounds for Treating Tumors (U.S. Patent No. 5,521,184). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/5521184/gleevec-imatinib
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does New Pyrimidine Chemical Compounds for Treating Tumors cover?
This patent describes specific new chemical compounds, called N-phenyl-2-pyrimidine-amine derivatives, designed with precise molecular structures for potential use in treating cancer.
Who owns patent US 5521184?
Ciba Geigy Corp owns this patent, granted in 1996.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 5521184 cited by?
This patent has been cited by 564 later patents that build on its ideas.
What problem does this patent solve?
This patent is foundational in pharmaceutical chemistry, defining a class of compounds with potential anti-tumor activity. It represents early work by Ciba Geigy, a company that later became part of Novartis, a major player in oncology. Such patents are critical for establishing intellectual property around new drug candidates, guiding further research and development in cancer treatment.
What does this patent NOT cover?
Does not cover pyrimidine derivatives that do not match the exact N-phenyl-2-pyrimidine-amine core structure of Formula I.
Same assignee
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