Methimazole impurities and related standards

Methimazole is held here as a working collection of 13 reference materials across 2 CAS numbers. 4 of the entries are impurity-type materials of the parent, 1 are salt or counter-ion variants and 1 carry a deuterium label and 3 are nitrosamine analogues. 2 entries carry a verified structure drawing, a coverage of 15%; the rest are listed without a structure rather than with an unverified one. 2 of them sit in tier A or B, meaning the data behind the page is complete enough to be indexed and quoted directly, while 11 remain tier C and are kept for search coverage. The lettered series exists because a pharmacopoeial monograph needed to name the impurities it controls, not because the letters follow any chemical order. Two suppliers can both claim coverage of a monograph and still hold different sets, so the comparison that matters is against the letter list in the monograph rather than against a catalogue heading. Where the impurity is a chiral species, the enantiomeric ratio belongs on the specification alongside the chemical purity, because an achiral method reports the two together as one peak.

Sources: DailyMed (US NLM) - METHIMAZOLE SOLUTION [FELIX PHARMACEUTICALS PRIVATE LIMITED].

8 reference standards related to Methimazole held in the RSSE catalogue — pharmacopoeial impurities, non-compendial impurities, metabolites and labelled analogues where available.

In this group: 4 stable isotope labelled standards · 2 fine chemicals · 1 chemical reagent · 1 general reference standard. CAS numbers are listed for 8 of 8; 7 entries carry a structure drawing.

On this page

8 reference standards

All entries — structure, identifiers and pack sizes

1-Methyl-2-(methylthio)imidazole

CAS 14486-52-3C5H8N2S

MW 128.2

IN STOCKRS-U010572
1-Methylimidazole

CAS 616-47-7C4H6N2

MW 82.1

IN STOCKRS-C001138
1-Methylimidazole-d3

CAS 16650-76-3C4H3D3N2

MW 85.12

CUSTOM SYNTHESISRS-I094303
2,2-Dimethoxy-N-methylethanamine

CAS 122-07-6C5H13NO2

MW 119.16

IN STOCKRS-U051062
2-Methylimidazole-d5

CAS 697806-98-7C4HD5N2

MW 87.13

IN STOCKRS-I094410
4-Methylimidazole-[D3]

CAS 1219805-95-4C4H6N2

MW 85.12

IN STOCKRS-I094163
Methimazole-13CD3

CAS 2772268-04-7C5H12NPb+3

MW 294.07

CUSTOM SYNTHESISRS-Z401GYQ
Thiamazole D3

CAS 1160932-07-9C4H3D3N2S

MW 117.2

IN STOCKRS-I003334

8 reference standards

Frequently asked

How many methimazole-related reference standards do you hold?

8 standards are listed on this page as of the latest catalogue build. CAS numbers are published for 8 of them and 7 entries carry a structure drawing. The catalogue is extended as new lots are released.

Can you supply a Methimazole impurity that is not listed here?

Yes. Non-compendial impurities can be quoted from a structure — a CAS number is not required. Send the structure, a SMILES string or the parent drug substance with your enquiry and we will come back with availability.

What documentation is supplied with methimazole impurities?

Every lot ships with its own certificate of analysis. The certificate records the catalogue number, the batch number, the tests performed, the specification applied and the result obtained for that lot. A safety data sheet is supplied with the shipment.

Do you publish prices or a lead time for methimazole impurities?

No price list is published: quotations are prepared per enquiry, because availability and packing depend on the lot and the quantity you need. Send the catalogue number and the quantity and a technical contact will answer with availability and a quotation.

Cannot find the impurity you need? Non-compendial impurities can be quoted from a structure — a CAS number is not required. Write to sales@rssechem.com.