P&D has additional advantages for this study. An important one is that chemical structures from all sources are standardised after importation. This means that our internal comparisons are as rigorous as we can make them (notwithstanding cheminformatic nuances that preclude this from being perfect). We have used the standardiser python package for saltstriping, charge neutralization, standardizing common functional groups, preserving stereochemistry and identification of the main active pharmaceutical ingredients (API) in mixtures. Structural uniqueness is based on the InChIKey, a hashed version of the International Chemical Identifier, InChI . Within the text of this article, we have used InChIKeys to designate mentioned compounds. These can not only be searched against P&D and all major databases but also in Google . On our website, users can choose to browse and compare the structures in three different forms: 1) standardized; 2) original (i.e. as imported from the source) and 3) non-isomeric (i.e. core connectivity without stereochemistry). Importantly, we made the considered decision not to submit our entire content to PubChem for two main reasons. The first is to reduce non-obvious circularity which can confound database users. The second is that this enables informative Boolean query combinations to be made between P&D sets and essentially any PubChem source or filtration selects.