How to retrieve anonymous subclass from OWL in SPARQL

Question

I am unsure of the SPARQL query needed to replicate the results of DL Query "has part some benzamide".

That query should return all entities that have some part that is a benzamide or a subclass of benzamide.

My SPARQL attempt:

PREFIX opioid: <https://mac389.github.io/ontology#>
          SELECT ?substance ?substance_label
          { ?substance rdfs:subClassOf* opioid:chemical_entity.
            ?substance rdfs:subClassOf* / opioid:has_part / owl:someValuesFrom opioid:benzamide. 
            ?substance rdfs:label ?substance_label }

Link to OWL as RDF/XML

In this code the 1st and 3rd lines work as intended, retrieving a list of all chemical entities and their labels. When I add the second line, the query returns no answers (there should be 21 items which is what the DL Query in Protege returns).

How does one query for anonymous subclasses like this?

I have looked at this question but I am looking for a subclass that only fulfills one of the property restrictions. I don't fully understand the answer to this question, but mine seems very related.