1 3 6 heptatrieno July 8, 2019 16 32 64 128 5 etinil 1 3 6 heptatrieno 3 etil 1 4 6 heptatrieno 6-metil-1 3 5-heptatrieno 6 etil 2 metil 1 3 6 heptatrieno 1 6 heptadiyne 1 3 5-heptatriene structural formula