N-Nitrosamines
In 2018, nitrosamine impurities became a focus for authorities, when a recall of angiotensin II receptor blocker (ARB) medicines, known as “sartans”, was announced. In bioactive compounds, a toxic impurity, N-nitrosodimethylamine (NDMA), was found. Since then, more cases of drug product batches contaminated with nitrosamines came to be known (Ranitidine, Nizatidine and Metformin). In 2020, FDA announced the availability of a guidance for industry, entitled “Control of N-Nitrosamine Impurities in Human Drugs.” In this context, Enamine offers a library of various nitrosamines for investigation.
Chemical structures of 7 potential nitrosamine impurities in APIs and drug products identified by FDA in 2020:
Case studies
Representative reaction to form nitrosamines:

- Nitrosamine compounds can form by a nitrosating reaction between amines and nitrous acid.
- Nitrosamine compounds are potent genotoxic agents in several animal species and some are classified as probable or possible human carcinogens.
We offer
More than 50 of nitrosamines from stock on a 5-10 g scale.
MedChem Highlights
- Boron-containing heterocyclic scaffolds with active halogens
- Aliphatic Pinacol Boronates for Medicinal Chemistry
- Deuterium-Containing Building Blocks for Drug Design
- Analogues of Piperidine for Drug Design
- SnAP Reagents
- Fluoroalkyl ethers for Drug Design
- N-Nitrosamines
- N-Trifluoromethyl Azoles for Drug Discovery
- Cyclic sulfates and sulfamidates as alkylating reagents
- Saturated Bioisosteres for ortho-substituted Benzenes
- Aliphatic Trifluoroborates (-BF3) for C-C couplings
- Functionalized Vinyl Boronates for C-C couplings
- Unique 3D-shaped Spirocycles
- Water-soluble non-classical benzene mimics
- gem-Difluorinated Amines for Drug Design
- Fluorosulfates and Sulfamoyl Fluorides
- Alkyne-containing Linkers
- Structurally optimized tetrazines for rapid biological labeling
- Building blocks and linkers for PROTAC synthesis
- Heterocyclic Sulfonyl Fluorides
- Silicon-Containing Building Blocks
- Epoxides for Drug Design
- Analogues of CF3-Pyridine for Drug Design
- Piperazine Bioisosteres for Drug Design
- Sugar-like Building Blocks for Drug Design
- Cyclic Sulfonamides for Drug Design
- Morpholine Bioisosteres for Drug Design
- P(O)Me2-containing Building Blocks
- Saturated Bioisosteres of ortho-/meta-substituted Benzenes
- Saturated bioisosteres of para-substituted benzenes
- Sulfonyl fluorides (-SO2F)
- Diazirines
- Oxetane-containing Building Blocks
- SF5-Building Blocks
- Stannanes for coupling reactions
- Sulfoximines for Drug Design
- Heterocyclic scaffolds
- Azide-linkers for Drug Design
- Unnatural Amino Acids
- Cubanes for Medicinal Chemistry
- Benzoxaboroles for Drug Design