| —— | 
                                        (4S,5R)-(-)-1-(3,4-dimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        56151-96-3 | 
                                        C21H31NO5 | 
                                        377.481 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (4R,5R)-(+)-1-(3,4-dimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        56152-02-4 | 
                                        C21H31NO5 | 
                                        377.481 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3R,4S)-(-)-1-(3,4-dimethoxyphenethyl)-3-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        56151-97-4 | 
                                        C21H31NO5 | 
                                        377.481 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3S,4S)-(+)-1-(3,4-dimethoxyphenethyl)-3-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        56151-98-5 | 
                                        C21H31NO5 | 
                                        377.481 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3S,4S)-(-)-1-(3,4-dimethoxyphenethyl)-3-ethyl-4-piperidineethanol | 
                                        56193-96-5 | 
                                        C19H31NO3 | 
                                        321.46 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3R,4R)-(+)-1-(3,4-dimethoxyphenethyl)-3-ethyl-4-piperidineethanol | 
                                        56193-98-7 | 
                                        C19H31NO3 | 
                                        321.46 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3R,4S)-(+)-1-(3,4-dimethoxyphenethyl)-3-ethyl-4-piperidineethanol | 
                                        75917-35-0 | 
                                        C19H31NO3 | 
                                        321.46 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (4R,5R)-(+)-1-(3,4-dimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetic acid | 
                                        56193-97-6 | 
                                        C19H27NO5 | 
                                        349.427 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (4S,5R)-(-)-1-(3,4-dimethoxyphenethyl)-5-ethyl-2-oxo-4-piperidineacetic acid | 
                                        56151-99-6 | 
                                        C19H27NO5 | 
                                        349.427 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (3S,4S)-(+)-1-(3,4-dimethoxyphenethyl)-3-ethyl-2-oxo-4-piperidineacetic acid | 
                                        75821-65-7 | 
                                        C19H27NO5 | 
                                        349.427 | 
                                    
                                                                                                                                                                                                                                                                                                                                                                                
                                                        
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
                                        | —— | 
                                        (4S,5R)-1-<2-(3,4-dimethoxyphenyl)-2-hydroxyethyl>-5-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        71333-94-3 | 
                                        C21H31NO6 | 
                                        393.48 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (+/-)-1-<2-(3,4-dimethoxyphenyl)-2-hydroxyethyl>-3-ethyl-2-oxo-4-piperidineacetic acid ethyl ester | 
                                        75821-62-4 | 
                                        C21H31NO6 | 
                                        393.48 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        (2S,3R,11bR)-(+)-3-ethyl-1,3,4,6,7,11b-hexahydro-9,10-dimethoxy-2H-benzoquinolizine-2-acetic acid ethyl ester | 
                                        75879-42-4 | 
                                        C21H31NO4 | 
                                        361.481 | 
                                    
                                                                                                                                            
                                        | —— | 
                                        9,10-dimethoxy-2β-ethoxycarbonylmethyl-3α-ethyl-1,3,4,6,7,11bα-hexahydro-2H-benzoquinolizine | 
                                        1245-02-9 | 
                                        C21H31NO4 | 
                                        361.481 |