There was a related question about displaying unknown and unspecified double bond stereochemistry in this forum, which initiated a very interesting discussion about the topic. The outcome of that discussion was (at least in my interpretation) that the crossed double bond representation is preferred over wavy bonds next to double bonds to indicate an unspecified or unknown (?) stereochemistry, although this contradicts with the IUPAC recommendations.
Noel O'Boyle [ Admin ]
It’s important not to conflate IUPAC recommendations on depiction and the best way of storing chemical information in MDL files. Notwithstanding the exact way information is stored in an MDL file, software could depict the structure according to IUPAC recommendations.