What should be alpha hydrogen score if there is no carbon on one side of the nitroso group? example Nitroso Sumatriptan Sulphonamide.
Structure:
1 Like
can we apply (0,3) alpha hydrogen and accordingly assign score of 2?
My first question would be if nitrosation would occur there or at the 3° amine after demethylation. However, CPCA is not designed for nitroso species other than nitrosamines.
2 Likes
Hello dear.
Appendix 2 mentions “The Carcinogenic Potency Categorisation Approach applies to N-nitrosamines bearing a carbon atom on both sides of the N-nitroso group, and where the carbon is not directly double bonded to a heteroatom”, in cases where N-Nitroso group is not bounded to 2 carbons CPCA cannot be apply. Any other nitrosamine impurities must have their limits defined using other methods.
3 Likes
As for sulphonamide, the LCDB contains only Diazalo, which appears insufficiently reliable. An Ames test would be an option.
3 Likes
Don’t forget that the indole can be nitrosated
4 Likes