Guanine

http://classyfire.wishartlab.com/tax_nodes/C0000000
http://classyfire.wishartlab.com/tax_nodes/C0000002
http://classyfire.wishartlab.com/tax_nodes/C0001797
http://classyfire.wishartlab.com/tax_nodes/C0000245
http://classyfire.wishartlab.com/tax_nodes/C0000245
http://classyfire.wishartlab.com/tax_nodes/C0004161
http://classyfire.wishartlab.com/tax_nodes/C0000078
http://classyfire.wishartlab.com/tax_nodes/C0004144
http://classyfire.wishartlab.com/tax_nodes/C0004139
http://classyfire.wishartlab.com/tax_nodes/C0004557
http://classyfire.wishartlab.com/tax_nodes/C0000323
http://classyfire.wishartlab.com/tax_nodes/C0000278
http://classyfire.wishartlab.com/tax_nodes/C0004150
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:16235
http://www.genome.jp/dbget-bin/www_bget?cpd:C00242
http://metacyc.org/META/new-image?type=COMPOUND&object=GUANINE
http://www.hmdb.ca/metabolites/HMDB0000132
http://www.genome.jp/dbget-bin/www_bget?cpd:C00242
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=764
https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=46507057
https://www.chemspider.com/Chemical-Structure.744.html
http://www.bindingdb.org/bind/chemsearch/marvin/MolStructure.jsp?monomerid=50200094
https://mor.nlm.nih.gov/RxNav/search?searchBy=RXCUI&searchTerm=1372539
https://www.ebi.ac.uk/chebi/searchId.do?chebiId=16235
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/CHEMBL219568
https://zinc.docking.org/substances/ZINC000000895129
http://bidd.nus.edu.sg/group/cjttd/ZFTTDDRUG.asp?ID=DNC000709
https://www.ebi.ac.uk/pdbe-srv/pdbechem/chemicalCompound/show/GUN
http://www.rxlist.com/cgi/generic/thioguanine.htm
https://en.wikipedia.org/wiki/Guanine