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Compound Libraries for Screening and Structure-Activity Relationship
Designed, made and quality-controlled compound sets — from a focused array around a scaffold to a screening collection off the shelf.
When you need chemical matter, not a chemistry problem solved
A search for chemical matter is brought on by one of two situations. Either a series needs a focused set of analogues around a scaffold, and the in-house team cannot make them fast enough, or a program needs screening compounds and needs them this month.
We have been building both for more than 25 years and have delivered over three million compounds in that time, for drug discovery and for agricultural and crop science programs. Library types cover parallel medicinal chemistry libraries, library enrichment projects, focused and targeted libraries, and virtual space.
Parallel medicinal chemistry libraries
Library synthesis has moved away from large combinatorial matrices toward small, focused sets that answer a specific medicinal chemistry question. Our parallel medicinal chemistry service is built for that.
- 20 to 200 compounds per library, rather than the thousands a traditional screening library implies
- Two-to-three-week cycle time
- 85% average success rate
- 46+ reaction types, 30+ ring-formation reactions, around 1,000 validated parallel reaction protocols
- A monomer performance database of more than 100,000 items, so building-block selection is informed by how those monomers have behaved rather than by what is purchasable
For a straightforward library, delivery can be as fast as seven calendar days from project initiation.
Virtual space
Where the starting points are not there, virtual space screening reaches chemical matter that no physical collection holds. The platform runs in three phases, each with a success rate of around 75 per cent.
- Building-block docking: 50 million virtual compounds, more than 90,000 building blocks, more than 40 reactions and more than 120 protocols, delivered in four to six weeks
- WuXi unique template: 9 billion virtual compounds, built on WuXi’s own templates and building blocks, with more reaction types and more protocols, delivered in six to eight weeks
- Drug-like core: 8.2 billion virtual compounds, designed around drug-like cores with more building blocks and docking against the protein, delivered in six to eight weeks
Off-the-shelf compounds
For screening rather than design work, our off-the-shelf collection holds more than 130,000 solids and solutions in stock, with more than 95 per cent satisfying the Lipinski rule of five and more than 99 per cent novelty.
Cycle time is one to two days. We ship roughly 200,000 samples a year.
Design and quality control
Every compound is analyzed by LCMS, 1H NMR, or both before it leaves us, with multi-level quality control behind that.
A screening set is only as good as the confidence you have that the compounds in the plate are the compounds on the list, which is why this is the part of the service we would rather be judged on than the throughput numbers.
Behind the libraries sit more than 50,000 reagents and 15,000 unique scaffolds and building blocks in stock, available to bench chemists within 24 hours, and an in-house reaction condition screening platform for the steps that do not work first time. Photoredox and electrochemistry are applied where they raise the completion rate of a library.
Libraries that arrive while the assay is running
A library is only useful in the window when the screen is live. A late delivery is added cost. Incomplete delivery is worse, because the SAR you draw can have holes you cannot see.
That is why design, synthesis and QC run as one workflow, so what arrives is what you planned to test.