No-par

http://classyfire.wishartlab.com/tax_nodes/C0000000
http://classyfire.wishartlab.com/tax_nodes/C0000002
http://classyfire.wishartlab.com/tax_nodes/C0002389
http://classyfire.wishartlab.com/tax_nodes/C0000189
http://classyfire.wishartlab.com/tax_nodes/C0000189
http://classyfire.wishartlab.com/tax_nodes/C0002228
http://classyfire.wishartlab.com/tax_nodes/C0004139
http://classyfire.wishartlab.com/tax_nodes/C0004557
http://classyfire.wishartlab.com/tax_nodes/C0004150
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:28568
http://www.hmdb.ca/metabolites/HMDB0014730
http://www.genome.jp/dbget-bin/www_bget?drug:D00807
http://www.genome.jp/dbget-bin/www_bget?cpd:C07973
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=4837
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46507642
https://www.chemspider.com/Chemical-Structure.13835459.html
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=8340
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=28568
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL1412
https://zinc.docking.org/substances/ZINC000005850277
http://bidd.nus.edu.sg/group/cjttd/ZFTTDDRUG.asp?ID=DAP001418
http://www.pharmgkb.org/drug/PA450977
https://www.ebi.ac.uk/pdbe-srv/pdbechem/chemicalCompound/show/PZE
https://www.drugs.com/cons/piperazine.html
https://en.wikipedia.org/wiki/Piperazine