H Nil Tube

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:41948
http://www.genome.jp/dbget-bin/www_bget?drug:D07883
http://www.genome.jp/dbget-bin/www_bget?cpd:C07997
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=3009
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=310264864
https://www.chemspider.com/Chemical-Structure.2902.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=50028197
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=569
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=41948
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL830
https://www.drugs.com/monograph/eflornithine.html
https://en.wikipedia.org/wiki/Eflornithine