Here's what rhymes with cyclopropane.

Consider these alternatives

pyridine / line thiophene / seen pyrrolidine / seen lactone / backbone bicyclic / epicyclic sulfonic / chronic orthoses / metamorphoses unsubstituted / included pyrrole / whole furan / an naphthalene / seen homoserine / seen trifluoroacetic / magnetic thioether / whether tholeiitic / racliitic cyclohexanone / known piperidine / seen macrocyclic / heterocyclic