Methionine

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:16643
http://www.genome.jp/dbget-bin/www_bget?cpd:C00073
http://www.hmdb.ca/metabolites/HMDB0000696
http://www.genome.jp/dbget-bin/www_bget?drug:D00019
http://www.genome.jp/dbget-bin/www_bget?cpd:C00073
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6137
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46505750
https://www.chemspider.com/Chemical-Structure.5907.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=50142500
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=6837
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=16643
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL42336
https://zinc.docking.org/substances/ZINC000001532529
http://www.pharmgkb.org/drug/PA450423
https://www.ebi.ac.uk/pdbe-srv/pdbechem/chemicalCompound/show/MET
http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/lme_0173.shtml
https://en.wikipedia.org/wiki/Methionine