2 3 5-trimethyloctane structure July 8, 2019 16 32 64 128 3 ethyl 2 4 5 trimethyloctane structure 2 methyl 2 butanol 2 3 5-trimethyloctane 3 methylhexane 2 2 5-trimethyloctane 2 3 3-trimethyl-1 4 6-octatriene