(1S-(1R*,3S*,4E,8E,12R*,13E))-1,5,9-trimethyl-12-(1-methylethyl)-4,8,13-cyclotetradecatriene-1,3-diol 2,7,11-Cembratriene-4,6-diol 57605-80-8 CCRIS 5452 alpha-2,7,11-Cembratriene-4,6-diol