Spring Intro 2023

28/03/2023

3.2.S.3 Characterisation

3.2.S.3.1 Elucidation of structure

NCE :

– Synthetic route – Spectral analyses – Elemental analysis – Isomerism, identification of stereochemistry

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Impurities

All chemical synthetic processes are likely to generate impurities. Impurities can arise from the raw materials or as by-products of the synthetic route. In principle, impurities are undesirable Minimisation of impurities ● Improve quality of raw materials / intermediates

● Change in process conditions ● Additional purification steps ● Change in chemistry – including different route? Impurity profile considerations ● Structural alerts (genotoxics) ● Analytical methodology – reporting thresholds ● Identified impurities ● Qualified impurities ● Control via the drug substance specification

The Organisation for Professionals in Regulatory Affairs

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