heptenes
CH2=CHCH2CH2CH2CH2CH3 hept-1-ene
CH3CH=CHCH2CH2CH2CH3 hept-2-ene
CH3CH2CH=CHCH2CH2CH3 hept-3-ene
CH3CH2CH2CH=CHCH2CH3 hept-3-ene
CH3CH2CH2CH2CH=CHCH3 hept-2-ene
CH3CH2CH2CH2CH2CH=CH2 hept-1-ene