Duplex

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:53579
http://www.hmdb.ca/metabolites/HMDB0041984
http://www.genome.jp/dbget-bin/www_bget?drug:D07385
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=5311356
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=310265116
https://www.chemspider.com/Chemical-Structure.4470854.html
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=33431
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=53579
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL2105224
https://zinc.docking.org/substances/ZINC000004217287
https://en.wikipedia.org/wiki/Pholcodine