What “rolapitant synthesis patent spiro” usually refers to
Searches for “rolapitant synthesis patent spiro” most often target patent documents that describe how to make rolapitant using (or generating) a spirocyclic intermediate. That word choice typically points to a specific patent family claim language where “spiro” describes a ring system in the synthetic route or an intermediate compound.
Which spiro-related structures show up in rolapitant manufacturing patents
Rolapitant itself is a small-molecule NK1 receptor antagonist. Patents covering its preparation commonly include:
- named intermediates, sometimes containing spiro-fused or spiro-annulated ring motifs (hence “spiro” in search queries)
- stepwise reaction sequences (couplings, cyclizations, functional group interconversions) that convert simpler starting materials into rolapitant or key late-stage intermediates
- claim language tying a particular spiro intermediate (or a method using it) to the final drug
Because “spiro” can appear in multiple contexts across different applicants and jurisdictions (process claims vs. intermediate claims vs. salt/polymorph claims), the most direct way to identify the correct patent is to anchor on a specific spiro compound name, CAS number, or the exact claim/paragraph where “spiro” appears.
How to find the exact rolapitant spiro synthesis patent quickly
Use any of these strategies in Google Patents / Espacenet:
- Search within the title/abstract/claims for: rolapitant AND spiro
- Add constraint terms that often co-occur with process chemistry: “preparation”, “process for preparing”, “intermediate”, “compound of formula”
- If you have any spiro intermediate identifier (name fragments, formula, or a synonym), search that together with rolapitant
- Filter by assignee/applicant once you identify likely parties (companies that file rolapitant synthesis/procedure patents)
What you might be looking for: “process” patents vs “compound” patents
Rolapitant patent coverage can split into different claim types:
- Process patents: methods for preparing rolapitant (or a key intermediate). These are where “synthesis” and spiro intermediates often matter.
- Compound patents: the drug substance (or specific intermediates) defined by chemical structure. “Spiro” may appear in the structural definition.
- Formulation/polymorph/salt patents: typically don’t revolve around “spiro” synthesis wording, unless the spiro structure is in the substance definition being claimed.
If you tell me the spiro intermediate name (or paste the snippet of the claim containing “spiro”), I can narrow to the most likely patent family and explain what that spiro-containing step is doing in the route.
If your goal is legal/expiry: why the “spiro synthesis” phrasing matters
When people look for a “synthesis patent,” they usually want to know whether a manufacturer can make rolapitant by switching routes around an expired “method” claim, or whether an intermediate/process claim still blocks them.
To assess that, you need:
- jurisdiction (US vs EP vs JP etc.)
- the specific patent number or publication number
- whether the spiro-related language is in an actual independent claim, and what exactly is claimed (the intermediate itself vs. a method step using it)
What I need from you to answer precisely
Right now, “Rolapitant synthesis patent spiro” is not specific enough to identify a single patent. Share one of the following and I’ll pinpoint the exact document(s) and summarize the spiro step:
- a patent number/publication number (US…, EP…, WO…)
- a link to the patent page
- the spiro intermediate’s chemical name or formula
- a quoted line where “spiro” appears
Sources: none (no patent documents were provided).