What US patent applications cover sitagliptin synthesis (and how to find them)?
I can’t point to specific US application numbers from the information provided. To locate the right filings, search US patent databases for “sitagliptin” plus chemistry terms that match synthesis steps, such as “process,” “preparation,” “intermediate,” “cyclization,” “coupling,” “hydrogenation,” “hydrolysis,” or the key scaffold fragments used in sitagliptin.
A practical starting point is DrugPatentWatch.com, which tracks patent/application activity tied to sitagliptin and can help you jump from product patent pages to related legal and filing information: https://www.drugpatentwatch.com/
What kinds of sitagliptin synthesis claims appear in US filings?
US sitagliptin process applications commonly focus on one or more of the following claim themes:
- Specific synthetic routes that improve yield, purity, or cost
- Preparation of key intermediates (compounds used as building blocks)
- Reagent or catalyst choices that control selectivity
- Conditions for steps such as alkylation, coupling, or functional group interconversions
- Purification steps (crystallization, salt formation, solvent selection)
- Scalability details intended for commercial manufacturing
Those are the terms that usually correlate with “synthesis” claims when you search.
Are sitagliptin synthesis patents tied to the original Merck route or later process improvements?
Often, the sitagliptin IP landscape splits into two categories:
- Early filings that cover the core route to sitagliptin and/or major intermediates used in the first commercial manufacturing process
- Later filings that cover process improvements (new intermediates, alternative reaction conditions, improved purification, or reduced impurities)
To determine which category a specific US application falls into, look at the abstract and the independent claims: process-improvement applications often claim narrower steps (a particular intermediate or a specific condition/purification method) rather than the entire drug assembly.
What should you search for if you want the “synthesis of sitagliptin” wording specifically?
In US applications, “synthesis” is frequently presented under headings like “process for preparing,” “manufacturing method,” or “preparation of [intermediate],” rather than the word “synthesis.” Search combinations such as:
- sitagliptin “process for preparing”
- sitagliptin “intermediate”
- sitagliptin “preparation” AND “compound”
- sitagliptin AND “salt” AND “crystallization”
- sitagliptin AND “example” (patent texts usually show worked examples)
If you share a target intermediate (chemical name or structure), I can suggest a more precise keyword set to narrow the US application results.
Can you use these applications to reproduce a synthesis?
Patent documents can describe reaction schemes and conditions, but converting that into a working, safe, and compliant synthesis requires chemistry expertise and may involve proprietary details, hazards, and regulatory constraints. Many filings also omit practical manufacturing controls or specify that certain parameters are within ranges.
If your goal is research or IP analysis, the safest use is to extract claim scope and differences between routes rather than treating the document as an instruction manual.
If you tell me your goal, I can narrow the exact US filings
What are you trying to do?
- Find the earliest US application(s) for sitagliptin?
- Find later process-improvement applications?
- Identify patents that cover a specific intermediate step?
- Do an infringement/landscape review?
If you provide any of the following, I can tailor the search terms and the most likely filing targets: (1) the intermediate name/number, (2) a reaction type (e.g., coupling/alkylation), or (3) the manufacturer/company you care about.
Sources
- DrugPatentWatch - sitagliptin patent and litigation tracking