Synthesis of 3′-Phosphate Adducts of Cyclopenta[cd]Pyrene with Deoxyguanosine via 3′-H-Phosphonate Intermediates

Abstract

32P-postlabeling, a highly sensitive chromatographic technique used to detect DNA adducts in vivo, requires synthetic chromatographic standards to definitively identify stereochemical configurations of adducts. Herein is reported a versatile synthetic route to stereo-chemically pure deoxyguanosine-3′-phosphate adducts of cyclopenta[cd]pyrene (CPP), a widespread environmental mutagenic and carcinogenic nonalternant PAH. The synthetic route, applicable to deoxyadenosine and other PAH nucleotide adducts, proceeds through a 3′-H-phosphonate intermediate which also serves as a valuable synthon for site-specifically modified oligomers. Stereochemically pure nucleotide adducts of CPP with deoxyguanosine were obtained by condensation of racemic trans 3-amino-4-hydroxy-CPP with 2-fluoro-2′-deoxyinosine-3′-H-phosphonate derivatives followed by oxidation to the corresponding 3′-phosphate and subsequent separation of the diastereomers by reverse phase HPLC. The separated adducts were characterized by proton and phosphorus NMR as well as mass spectrometry.