Penmalin

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:8232
http://www.hmdb.ca/metabolites/HMDB0014464
http://www.genome.jp/dbget-bin/www_bget?drug:D00466
http://www.genome.jp/dbget-bin/www_bget?cpd:C14034
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=43672
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46504757
https://www.chemspider.com/Chemical-Structure.39798.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=50240426
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=1546000
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=8232
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL702
https://zinc.docking.org/substances/ZINC000003913937
http://bidd.nus.edu.sg/group/cjttd/ZFTTDDRUG.asp?ID=DAP001164
http://www.pharmgkb.org/drug/PA450975
https://www.ebi.ac.uk/pdbe-srv/pdbechem/chemicalCompound/show/WPP
http://www.rxlist.com/cgi/generic3/piperacillin.htm
https://www.drugs.com/cdi/piperacillin.html
https://en.wikipedia.org/wiki/Piperacillin