ethyl 2-but-2-enyl-3-oxooct-6-enoate

ethyl 2-methyl-3-oxooct-6-enoate

dimethyl-2,2 thia-3 heptene-5(Z)

(E)-1-tert-butylsulfanylbut-2-ene

trimethyl-2,2,4 thia-3 hexene-5