Fig. 35

Standardization of Kekulé structure and aromaticity annotation. SID 7 is used as example, without annotation of stereochemistry or isotopic information for clarity. a Deposited structure of SID 7. b Intermediate representation of the same structure with bond order information in the aromatic system deleted. All bonds are represented as aromatic bonds. This structure is submitted to the OEKekulize function of the OpenEye OEChem C++ toolkit that generates a Kekulé form with single and double bonds instead of aromatic bonds. c Result of the aromaticity standardization. The detection of aromaticity, deletion of bond orders and Kekulization resulted in a different Kekulé structure