(-)-secologanin(-)-Secologanin3-Ethenyl-2-(beta-D-glucopyranosyloxy)-3,4-dihydro-4-(2-oxoethyl)-2H-pyran-5-carboxylic acid, methyl esterMETHYL (2S,3R,4S)-2-(BETA-D-GLUCOPYRANOSYLOXY)-4-(2-OXOETHYL)-3-VINYL-3,4-DIHYDRO-2H-PYRAN-5-CARBOXYLATESecologaninmethyl (2S,3R,4S)-4-(formylmethyl)-2-(beta-D-glucopyranosyloxy)-3,4-dihydro-3-vinyl-2H-pyran-5-carboxylatesecologanin