title: (15)N Double-labeled guanosine from inosine through ring-opening-ring-closing and one-pot Pd-catalyzed C-O and C-N cross-coupling reactions.
abstract: [N,1-(15)N(2)]-Guanosine, or [1,NH(2)-(15)N(2)]-guanosine, and derivatives were prepared from tri-O-acetylinosine, via N-nitration and reaction with (15)NH(2)OH, followed by conversion of the (15)N-labeled 1-hydroxyinosine to the corresponding 2,6-dichloropurine riboside. The sequential one-pot C-O and C-N key couplings of this dichloro derivative with PhCH(2)OH and PhCO(15)NH(2) or (i)PrCO(15)NH(2) was achieved in good overall yields, with Pd(0)-Xantphos as the best choice of five different catalytic systems examined.
authors.affiliation: Departament de Química Orgànica, Facultat de Química, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona, Catalonia, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Caner
authors.forename: Jaume
authors.initials: J
authors.lastname: Vilarrasa
mesh_terms: D002384:Catalysis; D003432:Cross-Linking Reagents / Q000737:chemistry*; D003500:Cyclization; D006151:Guanosine / Q000737:chemistry*; D007288:Inosine / Q000737:chemistry*; D015394:Molecular Structure; D010165:Palladium
chemical_list: D003432:Cross-Linking Reagents; D006151:Guanosine; D007288:Inosine; D010165:Palladium