Custom synthesis of the impurity you cannot find
A method validation usually stalls on one compound: an impurity that is not in any catalogue, a degradant that only appears in stressed samples, or a labelled analogue nobody sells. CATO synthesises those to order from a structure — a CAS number is not required, and every lot is released with its own certificate of analysis.
What we synthesise
If a compound is not on the catalogue, the question is whether it can be made — not whether it is listed.
How a custom project runs
- Send the structureSMILES, InChI, a drawing, a chemical name, or the parent drug substance plus the impurity designation. A CAS number is not required.
- Feasibility and quotationWe check the route and the reference material, then quote the pack size, the lead time and the documentation you asked for.
- Synthesis with in-process controlIntermediates are checked against the target specification, and you are told if the route has to change.
- Characterisation and dispatchThe content or purity of the material is assigned per batch and recorded on the certificate of analysis issued for that lot.
What to put in the first message
- The compound — structure, name, CAS number if it has one, or the parent API and the impurity designation (for example “Compound X EP Impurity B”).
- Why you need it — identification, system suitability, quantification or method validation. This decides which documentation matters.
- The quantity — the mass or the number of vials you need, and whether it may be split over more than one batch.
- The specification — any fixed purity, salt form, counter-ion or concentration your method requires.
- The date — when the material has to be in your hands, and the destination country.
If you hold the synthetic route, an impurity profile or a reference spectrum, mention it: it shortens the feasibility step considerably.
Start a custom request
One form, no account, and no price list: the reply covers feasibility, pack size, lead time and the documentation for the specific item.
What happens to the details you send
The enquiry goes to a technical contact, not to a ticket queue. It is used to answer the question: feasibility, the route that applies, the pack size and the date. Nothing is published, and no price is quoted anywhere on this site.
Not sure the compound can be made?
Send it anyway. A negative answer is useful too — it usually comes back with the reason and with the nearest compounds we do hold, which may be enough for the method.
Looking for a catalogue item instead?
Search the catalogue of 466 compounds by CAS number or name, browse related compounds by parent API, or read how identity and content are established before release.
Custom synthesis request
No account needed. Only the name and email are required — everything else helps us answer in one reply.
Custom synthesis — questions
Can you synthesise an impurity that is not in your catalogue?
Yes — that is a routine part of what we do. Non-compendial impurities, degradation products, metabolites and isotope-labelled analogues are quoted from a structure or from the parent drug substance, whether or not the compound has a CAS number or appears in any commercial catalogue.
What do you need in order to quote a custom impurity?
The structure — SMILES, InChI, a drawing or a chemical name — together with the parent drug substance, the quantity you need and the purity or documentation your method requires. A CAS number is helpful but not required. If you already hold the synthetic route or an impurity profile, send it and we will work from it.
How long does custom synthesis take?
It depends on the route and on whether the reference material already exists in our collections. The lead time is stated for the specific pack size in the written quotation, and you are told if it changes.
What scale can you work at?
From milligram scale for identification and system suitability work up to gram scale for larger validation batches. Quantities above the pack sizes listed in the catalogue are quoted on request.
How is a custom batch characterised and released?
The content or purity of the material is assigned per batch, and both the value and the analytical basis for it are recorded on the certificate of analysis issued for that lot. Values are assigned by HPLC, GC or qNMR, depending on the material.
Do you supply the analytical data as well as the certificate?
Every lot is released with its own certificate of analysis. If your method or your filing needs chromatograms or spectra in addition to the certificate, say so when you enquire: the quotation will state what can be provided for that item.
Can you isolate an impurity from material we already hold?
Yes. Isolation and purification from your own mixture, or from a related starting material, can be quoted when that is more practical than synthesis.
How is custom work priced?
Custom work is quoted per project rather than per catalogue entry, so the figure depends on the route, the scale and the documentation required. Prices are quoted per enquiry and none are published on this site — which is why the form asks for the details that determine the answer.
Send us a structure
Feasibility, pack size, lead time and documentation — answered in one reply.