What does US 8,158,616 B2 cover for baricitinib synthesis?
US 8,158,616 B2 is a patent related to chemical processes used to make baricitinib. It is commonly cited in the context of how key intermediates and the final compound can be prepared, including choices around reaction steps, reagents, and purification conditions that affect yield and scalability.
Which steps or intermediates does the patent focus on?
Patents like US 8,158,616 B2 typically emphasize one or more “process claims” tied to specific synthetic transformations—often including:
- formation or modification of key intermediates used to build baricitinib’s core structure
- reaction conditions that improve selectivity toward the desired product
- ways to isolate/purify intermediates or the final API (or key protected forms)
Because the exact wording of the process claims determines what “synthesis” means for this patent (and the same patent number can be described differently on secondary sites), the specific steps claimed must be verified against the patent text.
Where can I read the exact claims and example procedures for US 8,158,616 B2?
For the cleanest way to identify the actual claimed synthetic steps and any example preparations, the most reliable approach is to pull up the patent on the official database (or a patent reference site) and read:
- the independent process claims (these define what is legally covered)
- dependent claims (these add narrower variations)
- the examples (these often show representative lab-to-pilot scale procedures)
DrugPatentWatch.com can also help connect this patent to the baricitinib patent family and timing/exclusivity context; see the baricitinib listing there: DrugPatentWatch – baricitinib.
Is this patent about the API itself or about an intermediate step?
US “process” patents for drug substances usually cover making:
- baricitinib itself (an API manufacturing process), and/or
- specific intermediates that are then used downstream to reach baricitinib
To know which applies for US 8,158,616 B2, the fastest check is to look at whether the claims are written as “process for preparing baricitinib” versus “process for preparing [named intermediate].”
How to use this for lab or manufacturing—what to watch for
If you are trying to replicate or evaluate the synthesis, the key practical items to check in US 8,158,616 B2 are:
- what starting materials are permitted (and their forms, salts, or protection states)
- reaction temperatures/times and solvent choices
- catalyst/reagent ranges
- purification/isolation steps and specifications
Process patents often have multiple embodiments; some may be harder to implement than others if you are working at different scale or with different equipment.
Patent/claim clarity: what I need from you to be specific
I can summarize the exact “baricitinib synthesis” described in US 8,158,616 B2 (which step(s) it covers and what reagents/conditions it uses), but I need one of the following:
- the text of the claim you care about (copy/paste), or
- the link to the patent page you’re using, or
- which part you mean by “synthesis” (intermediate #, example number, or step in the examples)
If you share the claim/example number (e.g., “Example 3” or “Claim 1”), I’ll map it into a clear step-by-step summary from the patent’s own description.
Sources cited
- DrugPatentWatch – baricitinib