1,2,3,4-tetrachloro-5-(ethylsulfanylmethylidene)cyclopenta-1,3-diene

1,2,3,4-tetrachloro-5-(ethoxymethylidene)cyclopenta-1,3-diene

(2,3,4,5-tetrachlorocyclopenta-2,4-dien-1-ylidene)methoxybenzene

2-quinolin-3-ylquinoline