O6-Benzylguanine

O⁶-Benzylguanine (O6-BG) is a synthetic derivative of guanine. It is an antineoplastic agent. It exerts its effect by acting as a suicide inhibitor of the enzyme O6-alkylguanine-DNA alkyltransferase which leads to interruption of DNA repair. O6-BG was used clinically in combination with the alkylating agent temozolomide for glioblastoma, however the combination was found to be overly toxic without adding significant benefit.^[1][2][3]

O⁶-Benzylguanine

Names
IUPAC name 6-(Benzyloxy)-7H-purin-2-amine
Other names 6-(Benzyloxy)guanine; 6-O-Benzylguanine; O(6)-bGua; O6-BG
Identifiers
CAS Number	19916-73-5 Y
3D model (JSmol)	Interactive image
ChemSpider	4417
ECHA InfoCard	100.161.788
PubChem CID	4578
UNII	01KC87F8FE Y
CompTox Dashboard (EPA)	DTXSID20173700
InChI InChI=1S/C12H11N5O/c13-12-16-10-9(14-7-15-10)11(17-12)18-6-8-4-2-1-3-5-8/h1-5,7H,6H2,(H3,13,14,15,16,17) Key: KRWMERLEINMZFT-UHFFFAOYSA-N InChI=1/C12H11N5O/c13-12-16-10-9(14-7-15-10)11(17-12)18-6-8-4-2-1-3-5-8/h1-5,7H,6H2,(H3,13,14,15,16,17) Key: KRWMERLEINMZFT-UHFFFAOYAI
SMILES Nc3nc(OCc1ccccc1)c2nc[nH]c2n3
Properties
Chemical formula	C12H11N5O
Molar mass	241.254 g·mol−1
Density	1.432 g/mL
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

O6-BG is also used as a biochemical tool in the study of DNA repair mechanisms.^{[citation needed]}