3-[4-[1-[(3,4-dimethoxyphenyl)methyl]-6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl]butanoyloxy]propyl 4-[1-[(3,4-dimethoxyphenyl)methyl]-6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl]butanoate;oxalic acid                                                                                                                                                                                                                                                                                                          生成                                                 
N,N'-5,9-Dioxa-4,10-dioxotridecylen-1,13-bis-tetrahydropapaverin