ethyl trans-1-(3,4,5-trimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetate

(4S,5S)-1-(2-benzyloxy-3,4-dimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetic acid ethyl ester

trans-2-ethoxycarbonylmethyl-3-ethyl-1,2,3,4,6,7-hexahydro-9,10,11-trimethoxybenzoquinolizinium iodide

<(-)-9-demethylisotubulosine>

(4R,5R)-(+)-5-ethyl-1-(3-hydroxy-4-methoxyphenethyl)-2-oxo-4-piperidineacetic acid ethyl ester