diethyl 2-prop-1-en-2-ylpropanedioate

diethyl 2-(2-methylbut-3-en-2-yl)propanedioate

2-甲基-1,4-戊二烯

4-ethyl-3-trimethylsilylhex-1-en-3-ol

((4-ethylhex-2-en-3-yl)oxy)trimethylsilane