2-butyl-5,6-dihydro-4H-cyclopenta[b]thiophene

2-(2,2,2-trifluoroethoxy)cyclopentan-1-one

10-Isopropyliden-anti-tricyclo[4.2.1.12,5]dec-3-en-9-on

5-(Spiro[4.4]non-3-en-1-yl)-2-cyclopenten-1-on

2-(Spiro[2.4]hepta-4,6-dien-4-yl)cyclopentanon