title: Catalysis of nucleophilic aromatic substitutions in the 2,6,8-trisubstituted purines and application in the synthesis of combinatorial libraries.
abstract: The following paper summarizes our work on compound libraries of 2,6,8-trisubstituted purines. This synthesis route on a polystyrene support begins with 2,6-dichloro purine making extensive use of catalysis. During the synthesis the polymer bound purines were brominated selectively on C8. The substitution reaction of C6-Cl by amines was found to be acid catalyzed. The substitution of C2-Cl by amines and aryls, as well as the substitution of a C8-Br by aryls, alkenyl and alkynyl groups can be catalyzed by transition metals. Under some bromination conditions novel selective oxidative transformations of 2-amino groups in 2,6-diamino purines have been found.
authors.affiliation: Pharmazentrum der Universitaet Basel, Basel, Switzerland.
authors.forename: Claudia
authors.initials: C
authors.lastname: Riva-Toniolo
authors.forename: Sascha
authors.initials: S
authors.lastname: Müller
authors.forename: Josette
authors.initials: J
authors.lastname: Schaub
authors.forename: Wolfgang K D
authors.initials: WK
authors.lastname: Brill
mesh_terms: D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D011137:Polystyrenes / Q000737:chemistry*; D011687:Purines / Q000737:chemistry*
chemical_list: D011137:Polystyrenes; D011687:Purines