Route scouting is the discipline of finding a better synthetic route to a known molecule. Better usually means one or more of: cheaper, greener, safer, or free of the intellectual property claims that block a competitor's route.
It's also one of the highest-leverage services a CDMO can offer. A route that shaves 30% off cost of goods for a validated commercial API translates to real margin over a five-year supply agreement, and it's exactly the kind of work European buyers most value in an Indian partner.
What we mean by route scouting
Route scouting is not just picking a synthesis off a paper and running it. It is a systematic, comparative process that produces a scored set of alternatives with lab-verified proof for the recommended candidate. A typical engagement runs 8-14 weeks and delivers 2-3 viable routes plus a proof of concept for the top-ranked option.
Stage 1 — Literature and patent review
Every engagement opens with a structured survey of academic and patent literature. We use commercial patent-search tools plus manual review, and produce an IP-freedom map showing which portions of the reaction space are constrained by live patent claims.
What we look for in the literature
- Reported routes to the target molecule, ranked by year and citation frequency.
- Common synthetic strategies (retrosynthetic 'moves') across published routes.
- Green-chemistry alternatives for critical steps (biocatalysis, catalytic hydrogenation, flow chemistry).
- Solvent and reagent trends — what the field has moved toward or away from.
- IP claim scope across the top-cited patents, with expiry dates flagged.
Stage 2 — Route ideation
With the literature and IP map in hand, we brainstorm 3-5 candidate routes, mixing published strategies with novel disconnections. Each candidate gets a short technical note: overall step count, critical bond formations, projected cost drivers, and any known hazards.
Stage 3 — Retrosynthesis and scoring
Each candidate route is retrosynthetically analysed and scored on five axes. The scorecard is our most concrete deliverable and the one buyers reference most.
- Cost
- Projected raw-material and consumables cost per kilogram, using current spot prices for key reagents and solvents.
- PMI (process mass intensity)
- Total mass of inputs divided by mass of product. Lower is greener. A well-designed route targets PMI under 30 for small molecules.
- Safety
- Hazard classification of each step — reactive intermediates, cryogenic operations, high pressures, controlled reagents.
- IP freedom
- Whether the route steps clear of live patent claims. Yes / No / Constrained (specific claim to design around).
- Timeline
- Projected weeks to validated pilot campaign, assuming standard equipment availability.
Stage 4 — Proof of concept
The top-ranked route from the scorecard goes to the bench for a proof of concept. We synthesise the target at lab scale (typically 100 mg to 5 g) with in-line analytical support, and characterise the product by HPLC, NMR, and IR at minimum.
Go / no-go criteria
Not every route survives the bench. A route is a 'no-go' if any of the following happen: a critical step fails to give reasonable yield, an impurity appears that cannot be purged, or a hazard emerges that changes the safety score materially. When we hit a no-go, we return to Stage 2 with the second-ranked candidate.
Stage 5 — Comparative report and handover
The engagement closes with a written report and a handover call. The report includes the full scorecard, the retrosynthetic analysis for every candidate, the PoC data package for the recommended route, and an IP-freedom memo with claims strategy where relevant.
Green chemistry across all stages
Green chemistry isn't a stand-alone stage; it's a consideration on every route decision. We evaluate solvent recovery potential, catalytic vs stoichiometric approaches, and biocatalytic alternatives whenever the target chemistry admits them. Green chemistry usually correlates with lower PMI, so it's not a trade-off against cost — it's the same variable seen from a different angle.
Common failure modes
- Chasing yield vs. yielding scalability — a 95% yield on a step that requires cryogenic isolation may lose to an 85% yield that runs at room temperature.
- IP blindness — proposing a route that infringes claims that were flagged in Stage 1 because the ideation session forgot to check the map.
- Over-designing for edge cases — building elegant chemistry for impurity profiles that never actually appear at scale.
- Ignoring analytical burden — a route that requires four HPLC methods with tight validation is more expensive to run than one that requires two.
“The scorecard is where the trade-offs stop being feelings and start being numbers. Once the numbers are on the table, the conversation with the client changes.”
What a good deliverable looks like
- A completed scorecard for every candidate route, not just the recommended one.
- A lab-verified proof of concept for the top-ranked route, with analytical characterisation of the product.
- An IP-freedom memo with named patents cross-referenced against each proposed step.
- A transfer-ready SOP for the recommended route, at bench scale.
- A written recommendation with rationale — the buyer should be able to defend the decision to their internal committee without our slides.
When to commission route scouting
The best time to commission a route scouting engagement is before you commit to a commercial supply agreement — the scorecard gives you leverage on price, terms, and validation timeline. The second-best time is when your existing route is showing pressure: PMI too high, cost creeping up, or an IP threat on the horizon.
If you have a molecule you want to scout, send a two-line brief. NDA in one business day, and we'll come back with a scoping proposal.