CAS publishes no structure

No structure was looked up through this CAS — either CAS Common Chemistry gives it no molecular formula, which is what it does for a UVCB or a commercial mixture, or a ruling in `commonchemistry-structure-decisions.json` calls it an unspecified isomer. PubChem answered it with a compound anyway: one component of the mixture, or something unrelated. Is the number really non-specific? Where the reason is `contradicted` instead, Common Chemistry gave a different structure from the one offered, and the compounds listed under stereo-only differ from it in stereochemistry alone.

commonchem-structure-exclusion