1. Could anyone share where I can obtain or purchase the reference standard for N-Nitroso N-Desmethyl Rosuvastatin?
2. I was told that synthesizing N-Nitroso N-Desmethyl Rosuvastatin is difficult and the request was declined. Does anyone know why the synthesis process is considered challenging? Please share any insights.
i can find some suppliers eg Synzeal and Veerpho.
Veerpho also provides failure report in case synthesis is not possible. there is a related discussion here Synthesis Attempts and Failure Report 
- Confirmatory Testing & Analytical Challenges - Nitrosamines Exchange
Dear Jueun,
regarding the N-Desmethyl Rosuvastatin, its activity as nitrosated molecule would be very low as its negative charge of the nitrogen would be extensively delocalized through the resonance with the aromatic ring and the sulfonyl group.
So, the possibility of the formation of the N-Nitroso N-Desmethyl Rosuvastatin would very low or even negligible.
Overall, given the fact that the formation (even theoritical) of the N-Nitroso N-Desmethyl Rosuvastatin requires demethylation and then nitrosation of a non-vulnerable amine, i would not consider as a risk this ‘‘nitrosamine’’.
thanks
Christos
As explained by Chrischar, environment of secondary nitrogen plays big role in nitrosamine formation reactions. I will also review and look for any source if available in india. You can please write to me for any requirements of nitrosamine impurites/NDSRIs @ kamal@riverxlab.com
Thank you for your response. I have contacted the following suppliers — SYNTHINK, SIMSON, VEEPHRO, CHEMICEA, ALLMPUS, SYNZEAL, MOLCAN, CLEARSYNTH, and PHARMAFFLITES — but the purchase could not be completed due to lack of stock and inability to synthesize the material.
