Appearex

https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:15956
http://www.genome.jp/dbget-bin/www_bget?cpd:C00120
http://www.hmdb.ca/metabolites/HMDB0000030
http://www.genome.jp/dbget-bin/www_bget?drug:D00029
http://www.genome.jp/dbget-bin/www_bget?cpd:C00120
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=171548
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46508694
https://www.chemspider.com/Chemical-Structure.149962.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=12
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=1588
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=15956
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL857
https://zinc.docking.org/substances/ZINC000035024346
http://www.pharmgkb.org/drug/PA448625
https://www.ebi.ac.uk/pdbe-srv/pdbechem/chemicalCompound/show/BTN
https://www.drugs.com/cons/biotin.html
http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/bio_0035.shtml
https://en.wikipedia.org/wiki/Biotin