Fig. 27

Examples for diverging annotation of stereochemistry in PubChem-standardized and InChI-derived structures. a SID 12127575, the phosphorus atom is not considered to be chiral by PubChem standardization. b Analogous case in SID 2438124. c SID 127817816, PubChem standardization recognizes that the stereogenic carbon atoms do not have neighbors of four different symmetry classes and removes the annotated stereo configurations. d SID 158375861, the fully configured double bond in (i) is not considered to be a stereocenter by PubChem standardization due to the identical symmetry classes of adjacent atoms in the ring system. In all cases: (i) InChI-derived structure; (ii) Structure after subsequent PubChem standardization